US20220218206A1 - Micro-optic probes for neurology - Google Patents

Abstract

An imaging system for a patient comprises an imaging probe. The imaging probe comprises: an elongate shaft for insertion into the patient and comprising a proximal end, a distal portion, and a lumen extending between the proximal end and the distal portion; a rotatable optical core comprising a proximal end and a distal end, the rotatable optical core configured to optically and mechanically connect with an interface unit; a probe connector positioned on the elongate shaft proximal end and surrounding at least a portion of the rotatable optical core and an optical assembly positioned in the elongate shaft distal portion and proximate the rotatable optical core distal end, the optical assembly configured to direct light to tissue and collect reflected light from the tissue. A shear-thinning fluid can be provided between the elongate shaft and the rotatable optical core, such as to reduce undesired rotational variations of the rotatable optical core.

Description

RELATED APPLICATIONS
• This application is a continuation application of U.S. patent application Ser. No. 15/566,041 (Docket No. GTY-001-US), titled “Micro-Optic Probes for Neurology”, filed Oct. 12, 2017, United States Publication Number 2018-0125372, published May 10, 2018, which in a National Phase entry of International PCT Patent Application Serial Number PCT/US2016/027764 (Docket No. GTY-001-PCT), titled “Micro-Optic Probes for Neurology” filed Apr. 15, 2016, Publication Number WO 2016/168605, published Oct. 20, 2016, which claims the benefit of: U.S. Patent Provisional Application Ser. No. 62/322,182, titled “Micro Optic Probes for Neurology”, filed Apr. 13, 2016 and U.S. Provisional Application Ser. No. 62/148,355, titled “Micro-Optic Probes for Neurology”, filed Apr. 16, 2015, the content of each of which is incorporated herein by reference in its entirety for all purposes. This application is related to: U.S. Provisional Application Ser. No. 62/212,173, titled “Imaging System includes Imaging Probe and Delivery Devices”, filed Aug. 31, 2015; the content of which is incorporated herein by reference in its entirety for all purposes.
FIELD
• Inventive concepts relate generally to imaging systems, and in particular, neural imaging systems including imaging probes, imaging consoles and delivery devices.
BACKGROUND
• Imaging probes have been commercialized for imaging various internal locations of a patient, such as an intravascular probe for imaging a patient's heart. Current imaging probes are limited in their ability to reach certain anatomical locations due to their size and rigidity. Current imaging probes are inserted over a guidewire, which can compromise their placement and limit use of one or more delivery catheters through which the imaging probe is inserted. There is a need for imaging systems that include probes with reduced diameter, high flexibility and ability to be advanced to a patient site to be imaged without a guidewire, as well as systems with one or more delivery devices compatible with these improved imaging probes.
SUMMARY
• According to one aspect of the present inventive concepts, an imaging system for a patient comprises: an imaging probe and is configured to produce an image of the patient. The imaging probe comprises: an elongate shaft for insertion into the patient and comprising a proximal end, a distal portion, and a lumen extending between the proximal end and the distal portion; a rotatable optical core comprising a proximal end and a distal end, the rotatable optical core configured to optically and mechanically connect with an interface unit; a probe connector positioned on the elongate shaft proximal end and surrounding at least a portion of the rotatable optical core; and an optical assembly positioned in the elongate shaft distal portion and proximate the rotatable optical core distal end, the optical assembly configured to direct light to tissue and collect reflected light from the tissue.
• In some embodiments, the imaging probe comprises a shear-thinning fluid located within the distal portion of the elongate shaft, such as a shear-thinning fluid configured to reduce undesired rotational variances of the rotatable optical core (e.g. and the attached optical assembly130) while avoiding excessive loads being placed on the rotatable optical core.
• In some embodiments, the imaging probe further comprises at least one space reducing element positioned between the elongate shaft and the rotatable optical core, and the at least one space reducing element can be configured to reduce rotational speed variances of the rotatable optical core. The at least one space reducing element can be positioned at least in a portion of the elongate shaft distal portion. The at least one space reducing element can be configured to reduce the rotational speed variances by increasing the shear-thinning of the shear-thinning fluid.
• In some embodiments, the imaging probe further comprises an inertial assembly configured to reduce rotational speed variances of the rotatable optical core.
• In some embodiments, the imaging probe further comprises an impeller attached to the rotatable optical core and configured to resist rotation of the rotatable optical core when the rotatable optical core is retracted.
• In some embodiments, the imaging probe further comprises a stiffening element embedded into the elongate shaft that is configured to resist flexing of the elongate shaft and comprises an optically transparent portion.
• In some embodiments, the imaging probe further comprises a reduced inner diameter portion of the elongate shaft, wherein the reduced inner diameter portion is configured to reduce rotational speed variances of the rotatable optical core.
• In some embodiments, the imaging system is configured to create a three dimensional image by retraction of the elongate shaft.
• In some embodiments, the imaging system is configured to detect and/or quantify malapposition of a flow diverter implanted in the patient.
• In some embodiments, the imaging system is configured to provide quantitative and/or qualitative information used to determine the size of a flow diverter to be implanted in the patient and/or position a flow diverter in the patient. The quantitative and/or qualitative information can comprise information related to a parameter selected from the group consisting of: perforator location; perforator geometry; neck size; flow diverter mesh density; and combinations thereof.
• In some embodiments, the imaging system is configured to image a stent retriever at least partially positioned in thrombus of the patient. The imaging system can be configured to image thrombus at least one of: thrombus not engaged with the stent retriever or thrombus not removed by the stent retriever.
• In some embodiments, the imaging system is configured to quantify a volume of thrombus in the patient. The quantified thrombus can comprise thrombus selected from the group consisting of: residual thrombus in acute stroke; thrombus remaining after a thrombus removal procedure; thrombus present after flow diverter implantation; and combinations thereof.
• In some embodiments, the imaging system is configured to provide implant site information, and the implant site information is used to select a particular implantable device for implantation in the patient. The system can further comprise the implantable device for implantation in the patient, and the implantable device can comprise a device selected from the group consisting of: stent; flow diverter; and combinations thereof. The implantable device can be selected based on an implantable device parameter selected from the group consisting of: porosity; length; diameter; and combinations thereof.
• In some embodiments, the imaging system is configured to provide porosity information of a device implanted in the patient. The porosity information can comprise porosity of a portion of the implanted device that is to be positioned proximate a sidebranch of a vessel in which the implanted device is positioned. The system can be configured to provide the porosity information based on a wire diameter of the implanted device. The system can further comprise the implanted device, and the implanted device can comprise a device selected from the group consisting of: stent; flow diverter; and combinations thereof. The imaging system can be further configured to provide information related to implanting a second device in the patient. The first implanted device can comprise a stent, and the second implanted device can comprise a flow diverter. The first implanted device can comprise a flow diverter and the second implanted device can comprise a flow diverter. The imaging system can be further configured to provide an image during deployment of the implanted device. The imaging system can be further configured to allow modification of the implanted device while the optical assembly is positioned proximate the implanted device. The modification can comprise a modification of the porosity of the implanted device. The system can further comprise a balloon catheter configured to perform the porosity modification.
• In some embodiments, the imaging system is configured to image at least one perforator artery of the patient. The at least one perforator artery can comprise a diameter of at least 50 μm. The system can further comprise a therapeutic device. The therapeutic device can comprise a device selected from the group consisting of: stent retriever; embolization coil; embolization coil delivery catheter; stent; covered stent; stent delivery device; aneurysm treatment implant; aneurysm treatment implant delivery device; flow diverter; balloon catheter; and combinations thereof.
• In some embodiments, the system further comprises at least one guide catheter. The at least one guide catheter can comprise a microcatheter. The microcatheter can comprise an inner diameter between 0.0165″ and 0.027″. The microcatheter can comprise an inner diameter between 0.021″ and 0.027″.
• In some embodiments, the imaging probe is constructed and arranged to access a vessel of a human being.
• In some embodiments, the imaging probe is configured to access blood vessels of the brain.
• In some embodiments, the elongate shaft comprises a material selected from the group consisting of: FEP; PTFE; Pebax; PEEK; Polyimide; Nylon; and combinations thereof.
• In some embodiments, the elongate shaft comprises a material selected from the group consisting of: stainless steel; nickel titanium alloy; and combinations thereof.
• In some embodiments, the elongate shaft comprises a first portion comprising a metal tube and a second portion comprising a braided shaft.
• In some embodiments, the elongate shaft comprises a hydrophobic material configured to reduce changes in length of the elongate shaft when the elongate shaft is exposed to a fluid.
• In some embodiments, the elongate shaft comprises an outer diameter that varies along the length of the elongate shaft.
• In some embodiments, the elongate shaft comprises an inner diameter that varies along the length of the elongate shaft.
• In some embodiments, the elongate shaft comprises an outer diameter between 0.006″ and 0.022″.
• In some embodiments, the elongate shaft comprises an outer diameter of approximately 0.0134″.
• In some embodiments, the elongate shaft comprises an inner diameter between 0.004″ and 0.012″. The elongate shaft can comprise a wall thickness of approximately 0.003″.
• In some embodiments, the elongate shaft comprises an outer diameter less than or equal to 500 μm.
• In some embodiments, the elongate shaft comprises an outer diameter less than or equal to 1 mm.
• In some embodiments, the elongate shaft comprises an outer diameter of approximately 0.016″. At least the most distal 30 cm of the elongate shaft can comprise an outer diameter less than or equal to 0.016″.
• In some embodiments, the elongate shaft can comprise an outer diameter of approximately 0.014″. The elongate shaft can be configured to be advanced through vasculature without a guidewire or delivery device. At least the most distal 30 cm of the elongate shaft can comprise an outer diameter less than or equal to 0.014″.
• In some embodiments, the elongate shaft comprises a mid portion proximal to the distal portion, and the distal portion comprises a larger outer diameter than the mid portion. The elongate shaft distal portion can comprise a larger inner diameter than the inner diameter of the mid portion. The larger outer diameter distal portion can surround the optical assembly.
• In some embodiments, the elongate shaft comprises a length of at least 100 cm. The elongate shaft can comprise a length of no more than 350 cm.
• In some embodiments, the elongate shaft comprises a length of at least 200 cm. The elongate shaft can comprise a length of at least 220 cm. The elongate shaft can comprise a length of at least 240 cm. The elongate shaft can comprise a length of approximately 250 cm.
• In some embodiments, the elongate shaft further comprises a middle portion, and the elongate shaft distal portion comprises a larger inner diameter than the elongate shaft middle portion. The elongate shaft distal portion inner diameter can be at least 0.002″ larger than the inner diameter of the elongate shaft middle portion. The elongate shaft distal portion can comprise a similar outer diameter to the outer diameter of the elongate shaft middle portion. The elongate shaft distal portion can comprise an outer diameter than is greater than the elongate shaft middle portion outer diameter. The elongate shaft distal portion outer diameter can be at least 0.001″ larger than the outer diameter of the elongate shaft middle portion. The elongate shaft distal portion can comprise a wall thickness that is less than the elongate shaft middle portion wall thickness. The elongate shaft distal portion can comprise a stiffer material than the elongate shaft middle portion. The elongate shaft distal portion can comprise a stiffening element.
• In some embodiments, the elongate shaft distal portion comprises a rapid exchange guidewire lumen. The guidewire lumen can comprise a length of less than or equal to 150 mm. The guidewire lumen can comprise a length of at least 15 mm. The guidewire lumen can comprise a length of at least 25 mm.
• In some embodiments, the elongate shaft distal portion comprises an optically transparent window, and the optical assembly is positioned within the optically transparent window. The optically transparent window can comprise a length less than 20 mm, or less than 15 mm. The optically transparent window can comprise a material selected from the group consisting of: Pebax; Pebax 7233; PEEK; amorphous PEEK; polyimide; glass; sapphire; nylon 12; nylon 66; and combinations thereof. The elongate shaft can comprise at least a first portion, positioned proximate the optically transparent window, and the first portion can comprise a braided shaft. The elongate shaft can further comprise a second portion positioned proximal to the first portion, and the second portion can comprise a metal tube. The optically transparent window can comprise a length between 1 mm and 100 mm. The optically transparent window can comprise a length of approximately 3 mm. The optically transparent window can comprise a material selected from the group consisting of: nylon; nylon 12; nylon 66; and combinations thereof.
• In some embodiments, the elongate shaft comprises a stiffening element. The stiffening element can be positioned at least in the elongate shaft distal portion. The stiffening element can be constructed and arranged to resist rotation of the elongate shaft distal portion during rotation of the rotatable optical core. The stiffening element can terminate proximal to the optical assembly. The stiffening element can comprise a coil. The stiffening element can comprise metal coils wound over PTFE. The stiffening element can comprise a coil wound in a direction such that rotation of the rotatable optical core tightens the metal coil. The imaging probe can further comprise a fluid positioned between the rotatable optical core and the elongate shaft, and the metal coil can be configured to reduce twisting of the elongate shaft by torque forces applied by the fluid.
• In some embodiments, the elongate shaft comprises a distal end, and the imaging probe comprises a spring tip attached to the elongate shaft distal end. The spring tip can comprise a radiopaque portion. The spring tip can comprise a length between 2 cm and 3 cm.
• In some embodiments, the elongate shaft comprises a proximal portion constructed and arranged to be positioned in a service loop, and the elongate shaft proximal portion has a different construction than the remainder of the elongate shaft. The different construction can comprise a larger outer diameter. The different construction can comprise a thicker wall.
• In some embodiments, the system further comprises a fluid positioned in the elongate shaft lumen, and a fluid interacting element positioned in the distal portion of the lumen of the elongate shaft, and the fluid interacting element is configured to interact with the fluid to increase load on the rotatable optical core during rotation of the rotatable optical core. The fluid interacting element can comprise a coil positioned in the elongate shaft lumen. The fluid interacting element can comprise a non-circular cross section of the lumen. The non-circular cross section can comprise a geometry selected from the group consisting of: polygon shaped cross section of a lumen of the elongate shaft; projections into a lumen of the elongate shaft; recesses in inner diameter of the elongate shaft; and combinations thereof. The fluid can comprise a low viscosity fluid. The fluid can comprise a viscosity at or below 1000 Cp.
• In some embodiments, the imaging probe further comprises a first sealing element located within the elongate shaft lumen, the sealing element positioned between the rotatable optical core and the elongate shaft, and configured to slidingly engage the rotatable optical core and to resist the flow of fluid around the sealing element (e.g. to provide a seal as the rotatable optical core is rotated). The first sealing element can be positioned in the elongate shaft distal portion. The imaging probe can further comprise a first liquid positioned proximate the optical assembly and a second fluid positioned proximate the rotatable optical core, and the first sealing element can be positioned between the first liquid and the second liquid. The first liquid can comprise a first viscosity and the second liquid can comprise a second viscosity greater than the first viscosity. The first sealing element can be further configured to resist rotation of the rotatable optical core. The first sealing element can comprise a hydrogel. The first sealing element can comprise an adhesive bonded to the elongate shaft. The first sealing element can comprise a UV-cured adhesive bonded to the elongate shaft. The rotatable optical core can comprise a material that does not bond to the adhesive. The first sealing element can comprise a compliant material. The compliant material can comprise silicone. The system can further comprise a second sealing element positioned between the rotatable optical core and the elongate shaft, and the second sealing element can be configured to slidingly engage the rotatable optical core and can be further configured to resist flow of fluid around the second sealing element, and the imaging probe can further comprise a fluid positioned between the first sealing element and the second sealing element. The first and second sealing elements can be separated by a distance of between 1 mm and 20 mm. The fluid positioned between the first and second sealing elements can comprise a viscosity between 10 Cp and 100 Cp. The first sealing element can be positioned proximal and proximate the optical assembly and the second sealing element can be positioned distal to the first sealing element.
• In some embodiments, the imaging probe comprises a sealing element positioned proximate the proximal end of the elongate shaft. The sealing element can be positioned between the elongate shaft and the probe connector.
• In some embodiments, the rotatable optical core comprises a single mode glass fiber with an outer diameter between 40 μm and 175 μm.
• In some embodiments, the rotatable optical core comprises a single mode glass fiber with an outer diameter between 80 μm and 125 μm.
• In some embodiments, the rotatable optical core comprises a polyimide coating.
• In some embodiments, the rotatable optical core comprises an outer diameter between 60 μm and 175 μm. The rotatable optical core can comprise an outer diameter of approximately 110 μm.
• In some embodiments, the rotatable optical core comprises a material selected from the group consisting of: silica glass; plastic; polycarbonate; and combinations thereof.
• In some embodiments, the rotatable optical core comprises a numerical aperture of approximately 0.11.
• In some embodiments, the rotatable optical core comprises a numerical aperture of at least 0.11.
• In some embodiments, the rotatable optical core comprises a numerical aperture of approximately 0.16.
• In some embodiments, the rotatable optical core comprises a numerical aperture of approximately 0.20.
• In some embodiments, the rotatable optical core is constructed and arranged to rotate in a single direction.
• In some embodiments, the rotatable optical core is constructed and arranged to rotate in two directions.
• In some embodiments, the rotatable optical core is configured to be retracted within the elongate shaft. The system can further comprise purge media introduced between the rotatable optical core and the elongate shaft. The purge media can provide a function selected from the group consisting of: index matching; lubrication; purging of bubbles; and combinations thereof.
• In some embodiments, the optical assembly comprises an outer diameter between 80 μm and 500 μm. The optical assembly can comprise an outer diameter of approximately 150 μm.
• In some embodiments, the optical assembly comprises an outer diameter of at least 125 μm.
• In some embodiments, the optical assembly comprises a length between 200 μm and 3000 μm. The optical assembly can comprise a length of approximately 1000 μm.
• In some embodiments, the optical assembly comprises a lens. The lens can comprise a GRIN lens. The lens can comprise a focal length between 0.5 mm and 10.0 mm. The lens can comprise a focal length of approximately 2.0 mm. The lens can comprise a ball lens.
• In some embodiments, the optical assembly comprises a reflecting element.
• In some embodiments, the optical assembly comprises a lens, a reflecting element and a connecting element, and the connecting element positions the reflecting element relative to the lens. The connecting element can comprise an element selected from the group consisting of: tube; flexible tube; heat shrink; optically transparent arm; and combinations thereof. The connecting element can position the reflecting element a distance of between 0.01 mm and 3.0 mm from the lens. The connecting element can position the reflecting element a distance of between 0.01 mm and 1.0 mm from the lens. The reflecting element can comprise a cleaved portion of a larger assembly. The reflecting element can comprise a segment of a wire. The wire can comprise a gold wire. The lens can comprise a GRIN lens. The lens can have at least one of an outer diameter of 150 μm or a length of 1000 μm. The lens can further comprise a coreless lens positioned proximal to and optically connected to the GRIN lens.
• In some embodiments, the imaging probe comprises the inertial assembly, and the inertial assembly is positioned proximate the optical assembly.
• In some embodiments, the imaging probe comprises the inertial assembly, and the inertial assembly further comprises a wound hollow core cable comprising a proximal end and a distal end, the distal end of the wound hollow core cable being affixed to the rotatable optical core at a location proximal to the optical assembly, and the proximal end of the wound hollow core cable being unattached to the optical core.
• In some embodiments, the imaging probe comprises the inertial assembly, and the inertial assembly comprises fluid within the elongate shaft lumen and a mechanical resistance element positioned on the distal portion of the optical core, and the mechanical resistance element is in contact with the fluid and configured to resist rotation of the rotatable optical core.
• In some embodiments, the imaging probe comprises the inertial assembly, and the inertial assembly is constructed and arranged to provide inertial dampening which increases with rotational speed.
• In some embodiments, the imaging probe comprises the inertial assembly, and the inertial assembly comprises a projection from the rotatable optical core. The projection can be constructed and arranged to frictionally engage the elongate shaft. The projection can be constructed and arranged to cause shear force that applies a load to the rotatable optical core during rotation.
• In some embodiments, the imaging probe comprises the inertial assembly, and the inertial assembly comprises a projection from the elongate shaft. The projection can be constructed and arranged to frictionally engage the rotatable optical core. The projection can be constructed and arranged to cause shear force that applies a load to the rotatable optical core during rotation. The projection can be created by a thermal processing of the elongate shaft.
• In some embodiments, the imaging probe comprises the inertial assembly, and the inertial assembly comprises a compressed portion from the elongate shaft. The system can further comprise at least one band configured to crimp the elongate shaft to create the compressed portion.
• In some embodiments, the imaging probe comprises the inertial assembly, and the inertial assembly comprises the impeller.
• In some embodiments, the imaging probe comprises the impeller, and the impeller is constructed and arranged to cause wind-up loading of the rotatable optical core during rotation.
• In some embodiments, the imaging probe comprises the impeller and the imaging probe further comprises fluid in a lumen, and the impeller is configured to engage the fluid during rotation of the rotatable optical core.
• In some embodiments, the imaging probe comprises the impeller, and the impeller comprises a turbine.
• In some embodiments, the imaging probe comprises the impeller, and the impeller is configured to frictionally engage the elongate shaft during rotation of the rotatable optical core.
• In some embodiments, the imaging probe comprises the impeller, and the impeller comprises a vane-type micro structure.
• In some embodiments, the imaging probe comprises the impeller, and the impeller comprises a flywheel.
• In some embodiments, the imaging probe comprises the stiffening element.
• In some embodiments, the imaging probe comprises the stiffening element, and the stiffening element comprises a wire coil embedded in the elongate shaft, and the wire spiral geometry and a pullback spiral rotational pattern of the optical assembly are matched but offset by approximately one-half of a wire spiral, such that an imaging beam of the optical assembly passes between the wire spirals during pullback.
• In some embodiments, the imaging probe comprises the stiffening element, and the stiffening element comprises a wound wire formed over the rotatable optical core.
• In some embodiments, the imaging probe comprises the stiffening element, and the stiffening element comprises a stiffening member embedded in the elongate shaft, and the stiffening member geometry and a pullback spiral pattern of the optical assembly are matched but offset by approximately one-half of a wire spiral, such that an imaging beam of the optical assembly passes between the wire spirals during pullback.
• In some embodiments, the imaging probe comprises the reduced portion of the elongate shaft. The imaging probe can comprise at least one band crimped about the elongate shaft and constricting the elongate shaft to create the reduced portion of the elongate shaft. At least one band can provide a seal to be formed between the rotatable core and the elongate shaft. The reduced portion of the elongate shaft can comprise a thermally treated portion of the elongate shaft.
• In some embodiments, the imaging probe further comprises a fluid positioned within the lumen of the elongate shaft. The fluid can be configured to reduce variances in rotational speed of the rotatable optical core. The system can further comprise a sealing element positioned proximate the proximal end of the elongate shaft, and the seal can be configured to maintain the fluid within the lumen. The fluid can comprise a first fluid positioned around the optical assembly and a second fluid positioned around the rotatable optical core. The first fluid can comprise a first viscosity and the second fluid can comprise a second viscosity greater than the first viscosity. The second fluid can be constructed and arranged to reduce variances in rotational speed of the rotatable optical core. The system can further comprise a sealing element positioned between the first fluid and the second fluid. The fluid can comprise a gel. The fluid can comprise a shear-thinning fluid. The fluid can comprise a shear-thinning gel. The fluid can be configured to provide lubrication. The fluid can be configured to cause the rotatable optical core to tend to remain centered in the elongate shaft during rotation of the rotatable optical core. The first fluid can comprise a viscosity between 10 Pa-S and 100,000 Pa-S. The first fluid can be configured to reduce in viscosity to a level of approximately 3 Pa-S at a shear rate of 100 s-1. The fluid can comprise a lubricant configured to reduce friction between the rotatable optical core and the elongate shaft. The fluid can comprise a first fluid and a second fluid, and the second fluid can be positioned within the elongate shaft proximate the optical assembly, and the first fluid can be positioned within the elongate shaft proximal to the second fluid. The imaging probe can further comprise a sealing element in between the first fluid and the second fluid. The sealing element can be positioned between 1 mm and 20 mm from the optical assembly. The sealing element can be positioned approximately 3 mm from the optical assembly. The first fluid can comprise a viscosity between 10 Pa-S and 100,000 Pa-S. The first fluid can comprise a shear-thinning fluid. The first fluid can be configured to reduce in viscosity to a level of approximately 3 Pa-S at a shear rate of 100 s-1. The first fluid material can comprise a fluid selected from the group consisting of: hydrocarbon-based material; silicone; and combinations thereof. The second fluid can comprise a viscosity between 1 Pa-S and 100 Pa-S. The second fluid can comprise a viscosity of approximately 10 Pa-S. The second fluid can comprise a fluid selected from the group consisting of: mineral oil; silicone; and combinations thereof. The imaging system can be configured to pressurize the fluid in the lumen. The imaging system can be constructed and arranged to perform the pressurization of the fluid to reduce bubble formation and/or bubble growth. The imaging system can be configured to pressurize the fluid in the lumen to a pressure of at least 100 psi. The imaging system can comprise a pressurization assembly configured to perform the pressurization of the fluid. The pressurization assembly can comprise a check valve. The fluid can comprise a lubricant. The lubricant can be configured to reduce friction between the rotatable optical core and the elongate shaft when at least a portion of the elongate shaft is positioned proximate and distal to the carotid artery. The fluid can comprise a high viscosity fluid. The elongate shaft can be constructed and arranged to expand when the fluid is pressurized. The elongate shaft can be constructed and arranged to expand to a first inner diameter when the fluid is at a first pressure. The elongate shaft can be constructed and arranged to expand to a second inner diameter when the fluid is at a second pressure. The elongate shaft can be constructed and arranged to become more rigid when the fluid is pressurized. The elongate shaft can be constructed and arranged to increase space between the rotatable optical core and the elongate shaft during the expansion by the pressurized fluid. The elongate shaft can be constructed and arranged to remain at least partially expanded when the fluid pressure is reduced.
• In some embodiments, the imaging probe further comprises a torque shaft with a proximal end and a distal end, and the torque shaft can be fixedly attached to the rotatable optical core such that rotation of the torque shaft rotates the rotatable optical core. The torque shaft can comprise stainless steel. The torque shaft can comprise an outer diameter between 0.02″ and 0.09″. The torque shaft can comprise an outer diameter of approximately 0.025″. The torque shaft can comprise a length of approximately 49 cm. The torque shaft can comprise a dimension selected from the group consisting of: an inner diameter of approximately 0.015″; an outer diameter of approximately 0.025″; and combinations thereof. The torque shaft can comprise a wall thickness between 0.003″ and 0.020″. The torque shaft can comprise a wall thickness of approximately 0.005″. The torque shaft distal end can be positioned within 60 cm of the optical connector. The torque shaft distal end can be positioned within 50 cm of the optical connector. The torque shaft distal end can be positioned at least 50 cm from the optical assembly. The torque shaft distal end can be positioned at least 100 cm from the optical assembly. The imaging system can further comprise a retraction assembly constructed and arranged to retract at least one of the rotatable optical core or the elongate shaft, and the torque shaft distal end can be positioned proximal to the retraction assembly. The imaging probe can further comprise a fixation tube positioned between the torque shaft and the rotatable optical core. The fixation tube can be adhesively attached to at least one of the torque shaft or the rotatable optical core.
• In some embodiments, the imaging system further comprises a visualizable marker constructed and arranged to identify the location of the optical assembly on a second image produced by a separate imaging device. The separate imaging device can comprise a device selected from the group consisting of: fluoroscope; ultrasonic imager; MM; and combinations thereof. The visualizable marker can be positioned on the optical assembly. The visualizable marker can be positioned at a fixed distance from the optical assembly. The imaging system can further comprise a connecting element connecting the visualizable marker to the optical assembly.
• In some embodiments, the imaging probe can comprise multiple markers constructed and arranged to provide a rule function. The at least one of the multiple markers can comprise at least one of a sealing element or a rotational dampener. The multiple markers can comprise two or more markers selected from the group consisting of: radiopaque marker; ultrasonically reflective marker; magnetic marker; and combinations thereof. The multiple markers can be positioned on the rotatable optical core. The multiple markers can be positioned on the elongate shaft.
• In some embodiments, the imaging system further comprises a console comprising a component selected from the group consisting of: rotation assembly; retraction assembly; imaging assembly; algorithm; and combinations thereof.
• In some embodiments, the imaging system further comprises a rotation assembly constructed and arranged to rotate the rotatable optical core. The rotation assembly can comprise a motor. The imaging system can further comprise a retraction assembly constructed and arranged to retract at least one of the rotatable optical core or the elongate shaft. The imaging system can further comprise a translatable slide, and the rotation assembly can be positioned on the translatable slide. The rotation assembly can be constructed and arranged to be positioned independent of the position of the retraction assembly. The retraction assembly can be constructed and arranged to be positioned closer to the patient than the rotation assembly. The rotation assembly can provide motive force to the retraction assembly. The rotation assembly can comprise a drive cable that provides the motive force to the retraction assembly. The elongate shaft can be constructed and arranged to be retracted by the retraction assembly. The elongate shaft can comprise a proximal portion constructed and arranged to provide a service loop during retraction by the retraction assembly. The rotation assembly can rotate the rotatable optical core at a rate between 20 rps and 2500 rps. The rotation assembly can rotate the rotatable optical core at a rate of approximately 250 rps. The rotation assembly can rotate the rotatable optical core at a rate of up to 25,000 rps. The rotation assembly can be constructed and arranged to rotate the rotatable optical core at a variable rate of rotation. The imaging system can further comprise a sensor configured to produce a signal, and the rotational rate can be varied based on the sensor signal. The sensor signal represents a parameter selected from the group consisting of: tortuosity of vessel; narrowing of vessel; presence of clot; presence of an implanted device; and combinations thereof. The rotation assembly can be configured to allow an operator to vary the rate of rotation. The rotation assembly can be configured to automatically vary the rate of rotation. The rotation assembly can be configured to increase the rate of rotation when collecting image data from a target area.
• In some embodiments, the imaging system further comprises a retraction assembly constructed and arranged to retract at least one of the rotatable optical core or the elongate shaft. The retraction assembly can be constructed and arranged to retract the rotatable optical core without retracting the elongate shaft. The retraction assembly can be constructed and arranged to retract both the rotatable optical core and the elongate shaft. The retraction assembly can be constructed and arranged to retract the rotatable optical core and the elongate shaft simultaneously. The retraction assembly can be constructed and arranged to retract the rotatable optical core and the elongate shaft in unison. The imaging probe can comprise a fluid between the rotatable optical core and the elongate shaft, and the retraction assembly can be constructed and arranged to perform the retraction while minimizing bubble formation in the fluid. The elongate shaft distal portion can comprise an optically transparent window, and the optical assembly can be positioned within the optically transparent window. The optically transparent window can comprise a length of less than or equal to 6 mm, less than or equal to 15 mm, or less than or equal to 20 mm. The optically transparent window can comprise a length of between 5 mm and 50 mm. The optically transparent window can comprise a length of approximately 10 mm, or approximately 12 mm. The optically transparent window can comprise a length of less than or equal to 4 mm. The optically transparent window can comprise a length of approximately 3 mm. The elongate shaft can comprise an outer diameter less than or equal to 0.025″. The elongate shaft can comprise an outer diameter less than or equal to 0.016″. The elongate shaft can comprise an outer diameter less than or equal to 0.014″. The retraction assembly can be constructed and arranged to retract the elongate shaft. The elongate shaft can comprise a proximal portion constructed and arranged to provide a service loop during retraction by the retraction assembly. The retraction assembly can comprise a telescoping retraction assembly. The telescoping retraction assembly can comprise a disposable motor. The imaging probe can comprise a Tuohy valve and the retraction assembly can operably engage the Tuohy valve during retraction. The retraction assembly can be configured to perform a retraction over a time period of between 0.1 seconds and 10 seconds. The retraction assembly can be configured to perform a retraction over a time period of approximately 4 seconds. The retraction assembly can be constructed and arranged to retract the at least one of the rotatable optical core or the elongate shaft over a distance of approximately 50 mm. The retraction assembly can be constructed and arranged to retract the at least one of the rotatable optical core or the elongate shaft over a distance of approximately 75 mm. The retraction assembly can be constructed and arranged to retract the at least one of the rotatable optical core or the elongate shaft over a distance of between 20 mm and 150 mm. The retraction assembly can be constructed and arranged to have its retraction distance selected by an operator of the system. The retraction assembly can be configured to perform the retraction at a rate between 3 mm/sec and 500 mm/sec. The retraction assembly can be configured to perform the retraction at a rate of approximately 50 mm/sec. The retraction assembly can be constructed and arranged to retract the at least one of the rotatable optical core or the elongate shaft at a variable rate of retraction. The imaging system can further comprise a sensor configured to produce a signal, and the retraction rate can be varied based on the sensor signal. The sensor signal can represent a parameter selected from the group consisting of: tortuosity of vessel; narrowing of vessel; presence of clot; presence of an implanted device; and combinations thereof. The retraction assembly can be configured to allow an operator to vary the retraction rate. The retraction assembly can be configured to automatically vary the retraction rate. The retraction assembly can be configured to decrease the rate of retraction when visualizing a target area. The imaging system can further comprise a catheter device comprising at least one of a vascular introducer or a guide catheter, the elongate shaft insertable through the catheter device, and the retraction assembly can be attachable to the catheter device. The imaging system can further comprise a catheter device comprising at least one of a vascular introducer or a guide catheter, the elongate shaft insertable through the catheter device, and the retraction assembly can be constructed and arranged to be positioned within 20 cm from the catheter device.
• In some embodiments, the imaging system further comprises an imaging assembly configured to provide light to the rotatable optical core and to collect light from the rotatable optical core. The imaging assembly can comprise a light source configured to provide the light to the rotatable optical core. The imaging assembly can comprise a fiber optic rotary joint comprising an optical core configured to transmit light to the rotatable optical core and receive light from the rotatable optical core. The rotatable optical core can comprise a fiber with a first numerical aperture, and the imaging assembly can comprise an imaging assembly optical core with a second numerical aperture different than the first numerical aperture. The first numerical aperture can be approximately 0.16 and the second numerical aperture can be approximately 0.11. The imaging system can further comprise an adaptor configured to attach the imaging probe to the imaging assembly. The adaptor can comprise a lens assembly configured to match different numerical apertures. The adaptor can be configured to be used in multiple clinical procedures, but in less procedures than the imaging assembly. The adaptor can comprise a fiber with a numerical aperture chosen to minimize coupling losses between the imaging probe and the imaging assembly. The numerical aperture of the adaptor fiber can be approximately equal to the geometrical mean of the numerical aperture of the rotatable optical core and the numerical aperture of the imaging assembly. The numerical aperture of the adaptor fiber can be approximately equal to the arithmetic mean of the numerical aperture of the rotatable optical core and the numerical aperture of the imaging assembly.
• In some embodiments, the imaging system further comprises an algorithm. The imaging system can further comprise a sensor configured to produce a signal, and the algorithm can be configured to analyze the sensor signal. The sensor signal can represent light collected from tissue. The sensor signal can represent a parameter related to: tortuosity of a blood vessel; narrowing of a blood vessel; presence of clot; presence of implanted device; and combinations thereof.
• In some embodiments, the imaging system further comprises at least one guide catheter configured to slidingly receive the imaging probe. The imaging system can further comprise a flushing fluid delivery assembly configured to deliver a flushing fluid between the at least one guide catheter and the imaging probe. The flushing fluid can comprise saline and/or contrast (e.g. radiopaque contrast). The flushing fluid delivery assembly can be configured to deliver flushing fluid at a rate of approximately 6 ml/sec. The imaging system can further comprise the flushing fluid, and the flushing fluid can comprise iodinated contrast including an iodine concentration between 50 mg/ml and 500 mg/ml. The flushing fluid can comprise a fluid whose viscosity ranges from 1.0 Cp to 20 Cp at a temperature of approximately 37° C. The at least one guide catheter can comprise a first guide catheter comprising an optically transparent window, and the optical assembly can be constructed and arranged to be positioned within the optically transparent window. The first guide catheter can comprise a microcatheter with an inner diameter between 0.021″ and 0.027″. The first guide catheter can comprise a microcatheter with an inner diameter between 0.0165″ and 0.027″. The at least one guide catheter can further comprise a second guide catheter configured to slidingly receive the first guide catheter.
• In some embodiments, the imaging system further comprises a torque tool constructed and arranged to operably engage the elongate shaft and subsequently apply torsional force to the elongate shaft.
• According to another aspect of the present inventive concepts, methods of using the imaging system described herein are provided.
INCORPORATION BY REFERENCE
• All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference.
BRIEF DESCRIPTION OF THE DRAWINGS
• The foregoing and other objects, features and advantages of embodiments of the present inventive concepts will be apparent from the more particular description of preferred embodiments, as illustrated in the accompanying drawings in which like reference characters refer to the same or like elements. The drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the preferred embodiments.
• FIG. 1 is a schematic view of an imaging system comprising an imaging probe, an imaging console and one or more delivery devices, consistent with the present inventive concepts.
• FIG. 1A is magnified view of the distal portion of the shaft of the imaging probe ofFIG. 1, consistent with the present inventive concepts.
• FIG. 2 is a perspective view of an imaging probe comprising a metal coil in a distal portion of its shaft, consistent with the present inventive concepts.
• FIG. 3 is a chart illustrating non-uniform rotational distortion.
• FIG. 4 is a side sectional view of the distal portion of an imaging probe comprising a thin walled segment of shaft about an optical assembly, consistent with the present inventive concepts.
• FIG. 5 is a side sectional view of the distal portion of an imaging probe comprising two fluids within the shaft of the imaging probe, consistent with the present inventive concepts.
• FIG. 6 is a perspective view of an impeller, and a side sectional view of a distal portion of an imaging probe comprising the impeller, consistent with the present inventive concepts.
• FIG. 7 is a side sectional view of a proximal portion of an imaging probe comprising a pressurization element, consistent with the present inventive concepts.
• FIG. 8 is a side sectional anatomical view of a system comprising a guide catheter, an imaging probe and a treatment device, each of which having been placed into a vessel of the patient, consistent with the present inventive concepts.
• FIG. 9 is a side sectional anatomical view of the system ofFIG. 8, after the guide catheter has been partially retracted, consistent with the present inventive concepts.
• FIG. 10 is a side sectional anatomical view of the system ofFIG. 8, after the imaging probe has been advanced through the treatment device, consistent with the present inventive concepts.
• FIG. 11 is a side sectional anatomical view of the system ofFIG. 8, as the imaging probe is being retracted through the treatment device, consistent with the present inventive concepts.
• FIG. 12 is a side sectional anatomical view of a system comprising an imaging probe and a treatment device, consistent with the present inventive concepts.
• FIG. 13 is a side sectional view of an imaging probe comprising precision spacing between a rotatable optical core and a shaft, the spacing configured to provide capillary action to a fluid, consistent with the present inventive concepts.
• FIG. 14 is partially assembled view of an imaging probe comprising a shaft, rotatable optical core, and torque shaft, consistent with the present inventive concepts.
• FIG. 15A-C are side sectional views of an imaging probe in a series of expansion steps of its shaft via an internal fluid, consistent with the present inventive concepts.
• FIG. 16 is a side sectional view of the distal portion of an imaging probe comprising a distal marker positioned in reference to an optical assembly, consistent with the present inventive concepts.
• FIG. 17 is a side sectional view of the distal portion of an imaging probe comprising two sealing elements, consistent with the present inventive concepts.
• FIG. 18 is a side sectional view of the distal portion of an imaging device comprising a lens and deflector separated and connected by a projection, consistent with the present inventive concepts.
DETAILED DESCRIPTION OF THE DRAWINGS
• The terminology used herein is for the purpose of describing particular embodiments and is not intended to be limiting of the inventive concepts. Furthermore, embodiments of the present inventive concepts may include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing an inventive concept described herein. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise.
• It will be further understood that the words “comprising” (and any form of comprising, such as “comprise” and “comprises”), “having” (and any form of having, such as “have” and “has”), “including” (and any form of including, such as “includes” and “include”) or “containing” (and any form of containing, such as “contains” and “contain”) when used herein, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.
• It will be understood that, although the terms first, second, third etc. may be used herein to describe various limitations, elements, components, regions, layers and/or sections, these limitations, elements, components, regions, layers and/or sections should not be limited by these terms. These terms are only used to distinguish one limitation, element, component, region, layer or section from another limitation, element, component, region, layer or section. Thus, a first limitation, element, component, region, layer or section discussed below could be termed a second limitation, element, component, region, layer or section without departing from the teachings of the present application.
• It will be further understood that when an element is referred to as being “on”, “attached”, “connected” or “coupled” to another element, it can be directly on or above, or connected or coupled to, the other element, or one or more intervening elements can be present. In contrast, when an element is referred to as being “directly on”, “directly attached”, “directly connected” or “directly coupled” to another element, there are no intervening elements present. Other words used to describe the relationship between elements should be interpreted in a like fashion (e.g., “between” versus “directly between,” “adjacent” versus “directly adjacent,” etc.).
• It will be further understood that when a first element is referred to as being “in”, “on” and/or “within” a second element, the first element can be positioned: within an internal space of the second element, within a portion of the second element (e.g. within a wall of the second element); positioned on an external and/or internal surface of the second element; and combinations of one or more of these.
• Spatially relative terms, such as “beneath,” “below,” “lower,” “above,” “upper” and the like may be used to describe an element and/or feature's relationship to another element(s) and/or feature(s) as, for example, illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use and/or operation in addition to the orientation depicted in the figures. For example, if the device in a figure is turned over, elements described as “below” and/or “beneath” other elements or features would then be oriented “above” the other elements or features. The device can be otherwise oriented (e.g., rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly.
• The term “and/or” where used herein is to be taken as specific disclosure of each of the two specified features or components with or without the other. For example “A and/or B” is to be taken as specific disclosure of each of (i) A, (ii) B and (iii) A and B, just as if each is set out individually herein.
• As described herein, “room pressure” shall mean pressure of the environment surrounding the systems and devices of the present inventive concepts. Positive pressure includes pressure above room pressure or simply a pressure that is greater than another pressure, such as a positive differential pressure across a fluid pathway component such as a valve. Negative pressure includes pressure below room pressure or a pressure that is less than another pressure, such as a negative differential pressure across a fluid component pathway such as a valve. Negative pressure can include a vacuum but does not imply a pressure below a vacuum. As used herein, the term “vacuum” can be used to refer to a full or partial vacuum, or any negative pressure as described hereabove.
• The term “diameter” where used herein to describe a non-circular geometry is to be taken as the diameter of a hypothetical circle approximating the geometry being described. For example, when describing a cross section, such as the cross section of a component, the term “diameter” shall be taken to represent the diameter of a hypothetical circle with the same cross sectional area as the cross section of the component being described. Shafts of the present inventive concepts, such as hollow tube shafts comprising a lumen and a wall, include an inner diameter (ID) equal to the diameter of the lumen, and an outer diameter (OD) defined by the outer surface of the shaft.
• The terms “major axis” and “minor axis” of a component where used herein are the length and diameter, respectively, of the smallest volume hypothetical cylinder which can completely surround the component.
• The term “transducer” where used herein is to be taken to include any component or combination of components that receives energy or any input, and produces an output. For example, a transducer can include an electrode that receives electrical energy, and distributes the electrical energy to tissue (e.g. based on the size of the electrode). In some configurations, a transducer converts an electrical signal into any output, such light (e.g. a transducer comprising a light emitting diode or light bulb), sound (e.g. a transducer comprising a piezo crystal configured to deliver ultrasound energy), pressure, heat energy, cryogenic energy, chemical energy; mechanical energy (e.g. a transducer comprising a motor or a solenoid), magnetic energy, and/or a different electrical signal (e.g. a Bluetooth or other wireless communication element). Alternatively or additionally, a transducer can convert a physical quantity (e.g. variations in a physical quantity) into an electrical signal. A transducer can include any component that delivers energy and/or an agent to tissue, such as a transducer configured to deliver one or more of: electrical energy to tissue (e.g. a transducer comprising one or more electrodes); light energy to tissue (e.g. a transducer comprising a laser, light emitting diode and/or optical component such as a lens or prism); mechanical energy to tissue (e.g. a transducer comprising a tissue manipulating element); sound energy to tissue (e.g. a transducer comprising a piezo crystal); chemical energy; electromagnetic energy; magnetic energy; and combinations of one or more of these.
• As used herein, the term “patient site” refers to a location within the patient, such as a location within a body conduit such as a blood vessel (e.g. an artery or vein) or a segment of the GI tract (e.g. the esophagus, stomach or intestine), or a location with an organ. A “patient site” can refer to a location in the spine, such as within the epidural space or intrathecal space of the spine. A patient site can include a location including one or more of: an aneurysm; a stenosis; thrombus and/or an implant.
• As used herein, the term “neural site” refers to a patient site proximate the brain, such as at a location within the neck, head or brain of a patient. A neural site can include a location proximate the brain including one or more of: an aneurysm; a stenosis; thrombus and/or an implant.
• As used herein, the term “proximate” shall include locations relatively close to, on, in and/or within a referenced component or other location.
• As used herein, the term “transparent” and “optically transparent” refer to a property of a material that is relatively transparent (e.g. not opaque) to light delivered and/or collected by one or more components of the imaging system or probe of the present inventive concepts (e.g. to collect image data of a patient site).
• It is appreciated that certain features of the inventive concepts, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the inventive concepts which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable sub-combination. For example, it will be appreciated that all features set out in any of the claims (whether independent or dependent) can be combined in any given way.
• The present inventive concepts include imaging systems comprising imaging probes and one or more delivery devices, such as delivery catheters and/or guidewires. The imaging probe can be configured to be positioned proximate a patient site and to collect image data from the patient site, such as a neural site, spinal site and/or other patient site as defined hereabove. The imaging probe comprises an elongate shaft including a lumen. In some embodiments, a rotatable optical core and a distally positioned optical assembly are positioned within the lumen of the probe shaft. A probe connector can be positioned on the proximal end of the elongate shaft, the connector surrounding at least a portion of the rotatable optical core (e.g. the proximal end of the rotatable optical core). The present inventive concepts further includes methods of introducing the imaging probe to a patient site, such as a neural site, using one or more delivery devices such as delivery catheters and/or guidewires. In some embodiments, the imaging probe is advanced through a delivery catheter to a patient site, without being advanced over a guidewire.
• In some embodiments, the imaging probe comprises an inertial assembly configured to reduce rotational speed variances of the rotatable optical core. In some embodiments, the imaging probe comprises an impeller attached to the rotatable optical core and configured to resist rotation of the rotatable optical core, such as when the rotatable optical core is retracted.
• In some embodiments, the imaging probe comprises a reinforcing assembly embedded into the elongate shaft. The reinforcing assembly can be configured to resist flexing of the elongate shaft and can comprise an optically transparent portion.
• In some embodiments, the imaging probe comprises an elongate shaft in which at least a portion of the shaft includes a reduced inner diameter or otherwise comprises a portion in which the gap between the elongate shaft and the rotatable optical core is reduced. The reduced gap portion can be configured to reduce rotational speed variances of the rotatable optical core. In some embodiments, the reduced gap portion causes the elongate shaft to frictionally engage the rotatable optical core, providing a dampening force configured to reduce undesired speed variances of the rotatable optical core (e.g. to avoid undesired rotational speed variances in the attached optical assembly130). Alternatively or additionally, a fluid can be positioned in the reduced gap portion (or other locations between the elongate shaft and the rotatable optical core), such as to similarly reduce undesired speed variances of the rotatable optical core. The fluid can comprise a shear-thinning fluid configured to avoid excessive loading on the rotatable optical core (e.g. during high speed rotation to prevent breaking of the rotatable optical core).
• Systems, devices and methods of the present inventive concepts can be used to diagnose and/or treat stroke. Stroke is the 4th-leading cause of death in the United States and leads all ailments in associated disability costs. Stroke is a result of vascular disease and comes in two major forms: ischemic, in which the blood supply to the brain is interrupted; and hemorrhagic, in which a ruptured vessel leaks blood directly in the brain tissue. Both forms have associated high morbidity and mortality, such that improved diagnosis and treatment would have a significant impact on healthcare costs.
• Imaging of the vessels is the primary diagnostic tool when planning and applying therapies such as: thrombolytic drugs or stent retrievers for clot removal (ischemic stroke); or coils, flow diverters and other devices for aneurysm repair (hemorrhagic stroke). External, non-invasive, imaging technologies, such as x-ray, angiography or MRI, are the primary imaging techniques used, but such techniques provide limited information such as vessel size and shape information with moderate resolution (e.g. approximately 200 μm resolution). Such levels of resolution do not permit the imaging of important smaller perforator vessels present in the vasculature. An inability to adequately image these vessels limits pre-procedural planning as well as acute assessment of therapeutic results. These imaging technologies are further limited in their effectiveness due to the shadowing and local image obliteration that can be created by the therapies themselves (e.g. in the case of implantation of one or more coils). Thus there is a desire to also perform intravascular imaging to examine the detailed morphology of the interior vessel wall and/or to better plan and assess the results of catheter based interventions. Currently, intravascular imaging techniques such as Intravascular Ultrasound (IVUS) and intravascular Optical Coherence Tomography (OCT) have been developed, but are only approved for use in the coronary arteries. IVUS is also used in the larger peripheral vasculature. Currently, intravascular imaging has not been extended for use into the neurological vessels except for the larger carotid arteries. The limitations of current technologies correlate to: the neurological vessel sizes can become very small, on the order of 1 mm in diameter or less, and the vessel tortuosity becomes quite high (e.g. if attempting to navigate the tortuous carotid sinus to reach and image the mid-cranial artery as well as branches and segments above).
• Due to the fundamental limits of ultrasound resolution, especially the unavoidable beam spreading when small transducers are used, optical techniques are more appropriate. In particular, with the advent of new light sources such as broad band SLED's, visible wavelength laser diodes, and compact swept-frequency light sources, which are all compatible with single-mode fibers and interferometric imaging such as OCT, the use of optical techniques is highly advantageous both from a clinical performance as well as commercial viewpoint. The use of single mode fibers allows small diameter imaging catheters.
• Referring now toFIG. 1, a schematic view of an imaging system comprising an imaging probe and one or more delivery devices is illustrated, consistent with the present inventive concepts.System10 is constructed and arranged to collect image data and produce an image based on the recorded data, such as whensystem10 comprises an Optical Coherence Tomogrophy (OCT) imaging system.System10 comprisesimaging probe100, and at least one delivery device, such as at least onedelivery catheter50 and/or at least oneguidewire60.System10 can further comprise an imaging console,console200 which is configured to operably attach toimaging probe100.System10 can further comprise a fluid injector, such asinjector300 which can be configured to inject one or more fluids, such as a flushing fluid, an imaging contrast agent (e.g. a radiopaque contrast agent, hereinafter “contrast”) and/or other fluid, such asinjectate305 shown.System10 can further comprise an implant, such asimplant85 which can be implanted in the patient viaimplant delivery device80.System10 can further comprise a device configured to treat the patient,treatment device91, which can be configured to dilate a stenotic site, remove stenotic material (e.g. thrombus) and/or otherwise treat a patient disease or disorder.System10 can further comprise a second imaging device, such asimaging device92 shown.
• Imaging probe100 comprises an elongate shaft,shaft110, comprisingproximal end111,distal end119,proximal portion111a, a middle portion (mid portion115), anddistal portion119a. An optical connector,connector102 is positioned on theproximal end111 ofshaft110, such as a connector configured to operably attachprobe100 toconsole200.Imaging probe100 is configured to provide a patient image, such as a three dimensional (3D) image created whenshaft110 ofimaging probe100 is retracted. In some embodiments,imaging probe100 and/or another component ofsystem10 is of similar construction and arrangement to the similar components described in applicant's co-pending U.S. Provisional Application Ser. No. 62/148,355, titled “Micro-Optic Probes for Neurology”, filed Apr. 29, 2015, the content of which is incorporated herein in its entirety for all purposes.
• Imaging system10 can comprise one or more imaging probes100, each suitable for imaging highly tortuous bodily lumens such as the mid-cranial artery, various peripheral arteries, and ducts of the endocrine system such as the liver (bile) and pancreatic ducts. Eachimaging probe100 can comprise very small cross-sections, typically less than 1 mm in OD and contain a rotatable optical core,core120 comprising a single fiber optically connected on its distal end to an optical assembly,optical assembly130.Core120 is rotated to create a high fidelity image of the luminal wall through whichprobe100 is inserted.Imaging probe100 and other components ofimaging system10 can be configured to facilitate uniform rotational velocity ofcore120 while imagingprobe100 traverses difficult anatomies.Imaging system10 can comprise multiple imaging probes100 provided in a kit configuration, such as when two ormore probes100 comprise different characteristics (e.g. different length, diameter and/or flexibility)
• Imaging probe100 is constructed and arranged to collect image data from a patient site.Distal portion119acan be configured to pass through the patient site, such as a patient site including occlusive material such as thrombus or a patient site including an implant. In some embodiments,probe100 is constructed and arranged to collect image data from a neural site, such as a neural site selected from the group consisting of: artery of patient's neck; vein of patient's neck; artery of patient's head; vein of patient's head; artery of patient's brain; vein of patient's brain; and combinations of one or more of these. In some embodiments,probe100 is constructed and arranged to collect image data from one or more locations along or otherwise proximate the patient's spine. In some embodiments,probe100 is constructed and arranged to collect image data from tissue selected from the group consisting of: wall tissue of a blood vessel of the patient site; thrombus proximate the patient site; occlusive matter proximate the patient site; a blood vessel outside of blood vessel in whichoptical assembly130 is positioned; tissue outside of blood vessel in whichoptical assembly130 is positioned; extracellular deposits outside of the lumen of the blood vessel in whichoptical assembly130 is positioned (e.g. within and/or outside of the blood vessel wall); and combinations of one or more of these. Alternatively or additionally,optical assembly130 can be constructed and arranged to collect image data from an implanted device (e.g. a temporary or chronically implanted device), such asimplant85 described herebelow or a device previously implanted in the patient. In some embodiments,optical assembly130 is constructed and arranged to collect image data regarding the placement procedure in which the implant was positioned within the patient (e.g. real time data collected during placement).Optical assembly130 can be constructed and arranged to collect implant data comprising position and/or expansion data related to placement of an implant or other treatment device, such as a device selected from the group consisting of: a stent retriever (also known as a stentriever); an embolization device such as an embolization coil; an embolization coil delivery catheter; an occlusion device; a stent; a covered stent; a stent delivery device; a flow diverter; an aneurysm treatment device; an aneurysm delivery device; a balloon catheter; and combinations of one or more of these. In some embodiments,optical assembly130 is constructed and arranged to collect data related to the position of animplant85 or other device comprising a stimulation element, such as an electrode or other stimulation element positioned proximate the brain (e.g. an electrode positioned in the deep brain or other brain location) or a stimulation element positioned proximate the spine (e.g. stimulation element configured to treat pain by stimulating spine tissue). Implantation ofimplant85 can be performed based on an analysis of collected image data (e.g. an analysis of collected image data by algorithm240). The analysis can be used to modify an implantation parameter selected from the group consisting of: selection of the implantable device (e.g. selection of implant85); selection of the implantable device porosity; selection of the implantable device metal coverage; selection of the implantable device pore density; selection of the implantable device diameter; selection of the implantable device length; selection of the location to implant the implantable device; a dilation parameter for expanding the implantable device once implanted; a repositioning of the implantable device once implanted; selection of a second implantable device to be implanted; and combinations thereof. An adjustment of the implantation can be performed based on one or more issues identified in the analysis, such as an issue selected from the group consisting of: malposition of implanted device; inadequate deployment of implanted device; presence of air bubbles; and combinations thereof.
• In some embodiments,optical assembly130 is constructed and arranged to collect data related to the position of a treatment device, such astreatment device91 described herebelow, during a patient treatment procedure.
• Delivery catheters50 can comprise one or more delivery catheters, such asdelivery catheters50a,50b,50cthrough50nshown.Delivery catheters50 can include a vascular introducer, such as when delivery catheter50ashown inFIG. 1 comprises a vascular introducer,delivery catheter50_INTRO.Other delivery catheters50 can be inserted into the patient throughdelivery catheter50_INTRO, after the vascular introducer is positioned through the skin of the patient. Two ormore delivery catheters50 can collectively comprise sets of inner diameters (IDs) and outer diameters (ODs) such that afirst delivery catheter50 slidingly receives a second delivery catheter50 (e.g. the second delivery catheter OD is less than or equal to the first delivery catheter ID), and thesecond delivery catheter50 slidingly receives a third delivery catheter50 (e.g. the third delivery catheter OD is less than or equal to the second delivery catheter ID), and so on. In these configurations, thefirst delivery catheter50 can be advanced to a first anatomical location, thesecond delivery catheter50 can be advanced through the first delivery catheter to a second anatomical location distal or otherwise remote (hereinafter “distal”) to the first anatomical location, and so on as appropriate, using sequentially smallerdiameter delivery catheters50.
• Eachdelivery catheter50 comprises a shaft51 (e.g. shafts51a,51b,51cand51nshown), each with a distal end59 (e.g. distal ends59a,59b,59cand59nshown). A connector55 (e.g. connectors55a,55b,55cand55nshown) is positioned on the proximal end of eachshaft51. Eachconnector55 can comprise a Touhy or other valved connector, such as a valved connector configured to prevent fluid egress from the associated catheter50 (with and/or without a separate shaft positioned within the connector55). Eachconnector55 can comprise aport54 as shown ondelivery catheters50b,50c, and50n, such as a port constructed and arranged to allow introduction of fluid into the associateddelivery catheter50 and/or for removing fluids from an associateddelivery catheter50. In some embodiments, a flushing fluid, as described herebelow, is introduced via one ormore ports54, such as to remove blood or other undesired material from locations proximateoptical assembly130.Port54 can be positioned on a side ofconnector55 and can include a luer fitting and a cap and/or valve.Shafts51,connectors55 andports54 can each comprise standard materials and be of similar construction to commercially available introducers, guide catheters, diagnostic catheters, intermediate catheters and microcatheters used in interventional procedures.
• Eachdelivery catheter50 comprises a lumen52 (reference number52 shown on delivery catheter50abut removed from the remainingdelivery catheters50 for illustrative clarity) extending from theconnector55 to thedistal end59 ofshaft51. The diameter of eachlumen52 defines the ID of the associateddelivery catheter50. Eachdelivery catheter50 can be advanced over a guidewire (e.g. guidewire60) vialumen52. In some embodiments, adelivery catheter50 is configured for rapid exchange advancement and retraction over a guidewire, such as via a sidecar with a rapid exchange (Rx) guidewire lumen as is known to those of skill in the art. In some embodiments,probe100 and at least onedelivery catheter50 are cooperatively constructed and arranged such that thedelivery catheter50 is advanced through a vessel, such as a blood vessel, and probe100 is slidingly received by thedelivery catheter50 and advanced through thedelivery catheter50 to a location proximate a patient site PS to be imaged (e.g. a location just distal to, within and/or just proximate the patient site PS to be imaged). In some embodiments, asecond delivery catheter50 is slidingly received by afirst delivery catheter50, and probe100 is advanced through thesecond delivery catheter50 to a location proximate a patient site PS to be imaged. In yet other embodiments, three ormore delivery catheters50 are coaxially inserted in each other, withprobe100 advanced through theinnermost delivery catheter50 to a location proximate a patient site PS to be imaged. In some embodiments,probe100 is advanced through (e.g. through and beyond) one ormore delivery catheters50 without the use of a guidewire.
• Delivery catheters50 can comprise one or more delivery catheters selected from the group consisting of: an introducer; a vascular introducer; an introducer with an ID between 7 Fr and 9 Fr; a delivery catheter (also referred to as a guide catheter) for positioning through the aortic arch (e.g. such that its distal end is just distal or otherwise proximate the aortic arch) such as a delivery catheter with an ID between 5 Fr and 7 Fr or an ID of approximately 6.5 Fr; a delivery catheter (also referred to as an intermediate catheter) for insertion through a larger, previously placed delivery catheter, such as an intermediate delivery catheter with an ID of between 0.053″ and 0.070″; a delivery catheter (also referred to as a microcatheter) with an ID of between 0.0165″ and 0.027″; and combinations of one or more of these. In some embodiments,delivery catheters50 comprise afirst delivery catheter50_INTROcomprising an introducer, such as an introducer with an ID of between 7 Fr and 9 Fr or an ID of approximately 8 Fr.Delivery catheters50 further can further comprise asecond delivery catheter50 constructed and arranged to be inserted into thefirst delivery catheter50, such as asecond delivery catheter50_GUIDEconstructed and arranged for positioning through the aortic arch and comprising an ID between 5 Fr and 7 Fr or an ID of approximately 6 Fr.Delivery catheters50 can comprise athird delivery catheter50 constructed and arranged to be inserted through thefirst delivery catheter50_INTROand/or thesecond delivery catheter50_GUIDE, such as a third delivery catheter50_INTER(e.g. an intermediate catheter) with an ID of between 0.053″ and 0.070″.Delivery catheters50 can comprise afourth delivery catheter50_MICROconstructed and arranged to be inserted through the first, second and/orthird delivery catheters50, such as afourth delivery catheter50_MICROwith an ID of between 0.0165″ to 0.027″.Imaging probe100 can be constructed and arranged to be inserted through first, second, third and/orfourth delivery catheters50, such as when imagingprobe100 comprises an OD of less than 0.070″, such as when at least the distal portion ofimaging probe100 comprises an OD of less than or equal to 0.025″, 0.022″, 0.018″, 0.016″, 0.015″ or 0.014″. In some embodiments, at least the distal portion ofimaging probe100 comprises an ID of approximately 0.014″ (e.g. an ID between 0.012″ and 0.016″). In some embodiments,system10 comprises aprobe100 and one ormore delivery catheters50.
• Eachdelivery catheter50 can comprise an optically transparent segment, such as a segment relatively transparent to light transmitted and/or received byoptical assembly130, such astransparent segment57 shown on delivery catheter50nand described herein.Transparent segment57 can comprise a length of up to 50 cm, such as a length of between 1 cm and 15 cm, or a length of up to 2 cm or up to 5 cm.Transparent segment57 can be part of adelivery catheter50 comprising a microcatheter with an ID between 0.0165″ and 0.027″, or between 0.021″ and 0.027″.System10 can comprise afirst delivery catheter50 that slidingly receivesprobe100 and includes atransparent segment57, and asecond delivery catheter50 that slidingly receives thefirst delivery catheter50.
• Eachdelivery catheter50 can comprise a spring tip, not shown but such asspring tip104 described herein as attached toshaft110 ofprobe100.
• Guidewires60 can comprise one or more guidewires, such as guidewires60a,60bthrough60nshown.Guidewires60 can comprise one or more guidewires constructed and arranged to support advancement (e.g. intravascular advancement) of probe100 (e.g. via a rapid exchange lumen indistal portion119aof shaft110) and/or adelivery catheter50 into a patient site PS such as a neural site.Guidewires60 can comprise one or more guidewires selected from the group consisting of: a guidewire with an OD between 0.035″ and 0.038″; a guidewire with an OD between 0.010″ and 0.018″; an access length guidewire such as a guidewire with a length of approximately 200 cm; an exchange length guidewire such as a guidewire with a length of approximately 300 cm; a guidewire with a length between 175 cm and 190 cm; a guidewire with a length between 200 cm and 300 cm and/or an OD between 0.014″ and 0.016″; a hydrophilic guidewire; a Stryker Synchro™ guidewire; a Terumo guidewire such as the Terumo Glidewire™ guidewire; a Terumo Traxcess™ guidewire; an X-Celerator™ guidewire; an X-Pedion™ guidewire; an Agility™ guidewire; a Bentson™ guidewire; a Coon™ guidewire; an Amplatz™ guidewire; and combinations of one or more of these. In some embodiments,system10 comprises aprobe100 and one ormore guidewires60.Guidewires60 can comprise one or more visualizable portions, such as one or more radiopaque or ultrasonically reflective portions.
• System10 can comprise various sets and configurations ofdelivery catheters50 andguidewires60. In some embodiments,delivery catheters50 comprise afirst delivery catheter50_INTROcomprising an introducer (e.g. a vascular introducer), and at least twodelivery catheters50 that are inserted throughdelivery catheter50_INTRO, these catheters comprising corresponding different sets of IDs and ODs, such as to allow sequential insertion of eachdelivery catheter50 through thelumen52 of a previously placeddelivery catheter50, as described in detail herein. In some embodiments, afirst delivery catheter50 is advanced over afirst guidewire60, and a smallerOD delivery catheter50 is subsequently advanced over a smaller OD guidewire60 (e.g. after thefirst guidewire60 is removed from thefirst delivery catheter50 and replaced with the second guidewire60). In some embodiments, after image data is collected by animaging probe100 positioned within a delivery catheter (e.g. after a retraction in which the image data is collected),imaging probe100 is removed and replaced with aguidewire60 over which an additional device can be placed (e.g. anotherdelivery catheter50, atreatment device91, animplant delivery device80 or other device). In some embodiments,probe100, one ormore delivery catheters50 and/or one ormore guidewires60 are inserted, advanced and/or retracted as described herein.
• Probe100, one ormore delivery catheters50 and/or one ormore guidewires60 can be advanced to a patient site PS through one or more blood vessels (e.g. advancement of ormore delivery catheters50 over aguidewire60 through one or more arteries or veins). Alternatively or additionally,probe100, one ormore delivery catheters50 and/or one ormore guidewires60 can be advanced to a patient site PS via a non-blood vessel lumen, such as the epidural and/or intrathecal space of the spine, or via another body lumen or space (e.g. also as can be performed over a guidewire60).
• In some embodiments, one ormore delivery catheters50 comprise a functional element53 (e.g. functional elements53a,53b,53cand53nshown). Eachfunctional element53 can comprise one or more functional elements such as one or more sensors, transducers and/or other functional elements as described in detail herebelow. In some embodiments,shaft110 comprises a length of at least 100 cm, at least 200 cm, at least 240 cm. In some embodiments,shaft110 comprises a length of approximately 250 cm. In some embodiments,shaft110 comprises a length less than or equal to 350 cm, less than or equal to 250 cm, or less than or equal to 220 cm.
• In some embodiments,shaft110 comprises an outer diameter (OD) between 0.005″ and 0.022″ along at least a portion of its length (e.g. at least a portion ofdistal portion119a). In some embodiments,shaft110 comprises an OD of approximately 0.0134″, an OD at or below 0.014″ or an OD at or below 0.016″, along at least a portion of its length (e.g. along aportion surrounding core120 and/oroptical assembly130, and/or along at least the most distal 10 cm, 20 cm or 30 cm of shaft110). In these embodiments,imaging probe100 can be configured to be advanced and/or retracted without a guidewire or delivery catheter (e.g. whenoptical assembly130 andshaft110 are retracted in unison during collection of image data). In some embodiments,shaft110 comprises an OD that is less than 1 mm, or less than 500 μm, along at least a portion of its length. In some embodiments,shaft110 comprises an OD that changes along its length. In some embodiments,distal portion119acomprises a larger OD than an OD ofmid portion115, such as when the portion ofdistal portion119asurroundingoptical assembly130 has a larger OD than an OD ofmid-portion115. In these embodiments,distal portion119acan comprise a larger or similar ID as an ID ofmid portion115.
• In some embodiments,shaft110 comprises an inner diameter (ID) between 0.004″ and 0.012″, along at least a portion of its length. In some embodiments,shaft110 comprises an ID of approximately 0.0074″ along at least a portion of its length (e.g. along aportion surrounding core120 and/or optical assembly130). In some embodiments,shaft110 comprises an ID that changes along its length. In some embodiments,distal portion119acomprises a larger ID than an ID ofmid portion115, such as when the portion ofdistal portion119asurroundingoptical assembly130 has a larger ID than an ID ofmid-portion115.
• In some embodiments,shaft110 comprises a wall thickness of 0.001″ to 0.005″, or a wall thickness of approximately 0.003″, along at least a portion of its length (e.g. along aportion surrounding core120 and/oroptical assembly130. In some embodiments,shaft110 comprises a thinner wall surrounding at least a portion of optical assembly130 (e.g. thinner than a portion of the wall surrounding core120).
• In some embodiments,shaft110distal portion119ahas a larger ID thanmid portion115 ofshaft110, such as whenmid portion115 has an ID at least 0.002″ larger than the ID ofdistal portion119a. In these embodiments, the OD ofmid portion115 and the OD ofdistal portion119acan be of similar magnitude. Alternatively, the OD ofmid portion115 can be different than the OD ofdistal portion119a(e.g. the OD ofdistal portion119acan be greater than the OD ofmid portion115, such as whendistal portion119ais at least 0.001″ larger).
• In some embodiments,imaging probe100 comprises a stiffened portion, such as when imagingprobe100 comprises stiffeningelement118. Stiffeningelement118 is positioned in, within and/or along at least a portion ofshaft110. In some embodiments, stiffeningelement118 is positioned within or on the inside surface of the wall ofshaft110. In some embodiments, stiffeningelement118 comprises a wire wound overcore120. In some embodiments, stiffeningelement118 terminates proximal tooptical assembly130. Alternatively, stiffeningelement118 can travel lateral to and/or potentially beyondoptical assembly130, such as when the portion of stiffeningelement118 comprises one or more optically transparent materials.
• In some embodiments,distal portion119acomprises a wall thickness that is less than the wall thickness ofmid portion115. In some embodiments,distal portion119acomprises a stiffer material than the materials ofmid portion115, and/ordistal portion119aincludes a stiffening element (e.g. stiffening element118ashown inFIG. 13 herebelow), such as whendistal portion119acomprises a wall thickness less than the wall thickness ofmid portion115.
• In some embodiments,probe100 comprises a guidewire lumen, such as a rapid exchange guidewire lumen positioned in asidecar105 shown inFIG. 1.Sidecar105 can comprise a length of less than 150 mm.Sidecar105 can comprise a length of at least 15 mm, such as a length of approximately 25 mm.
• In some embodiments,proximal portion111aofshaft110 is configured to be positioned in a service loop.Shaft110proximal portion111acan comprise a different construction thanmid portion115 or different thandistal portion119a. For example,proximal portion111acan comprise a larger OD thanmid portion115 or a thicker wall thanmid portion115.
• In some embodiments,shaft110 comprises an outer shaft and an inner “torque” shaft, which can be shorter than the outer shaft, such as is described herebelow in reference toFIG. 14. In some embodiments, the torque shaft terminates prior to a portion ofprobe100 that enters the patient.
• In some embodiments,system10 comprisestorque tool320, a tool that frictionally engagesshaft110 of probe100 (e.g. from a lateral direction at a location alongproximal portion111a), and allows an operator to apply torsional force toshaft110.
• Referring additionally toFIG. 1A, a magnified view ofdistal portion119ais illustrated, consistent with the present inventive concepts. Alumen112 extends fromproximal end111 ofshaft110 todistal portion119a, ending at a location proximal todistal end119. Positioned withinlumen112 is a rotatable optical core,core120. An optical assembly,optical assembly130 is positioned on the distal end ofcore120.Optical assembly130 includeslens131, and a reflecting surface,reflector132.Optical assembly130 is positioned within an optically translucent and/or effectively transparent window portion ofshaft110,viewing portion117.Optical assembly130 is constructed and arranged to collect image data through at least a portion ofshaft110. In some embodiments,optical assembly130 is further constructed and arranged to collect image data through at least a portion of an additional device, such as at least a portion of a shaft of a delivery catheter50 (e.g. an optically transparent portion of adelivery catheter50, such astransparent segment57 described herein). InFIG. 1A, optional components sidecar105 and stiffeningelement118 have been removed for illustrative clarity.
• In some embodiments, a fluid190 is included in lumen112 (e.g. in the space not occupied bycore120 and optical assembly130), such asfluid190aandfluid190bshown inFIG. 1A where fluid190bis positioned aroundoptical assembly130, and fluid190ais positioned aroundcore120 proximal tooptical assembly130. Fluid190 (e.g. fluid190b) can comprise an optically transparent fluid. In some embodiments, fluid190aandfluid190bcomprise similar materials. Alternatively or additionally, fluid190aandfluid190bcan comprise dissimilar materials. In some embodiments, fluid190acomprises a more viscous fluid thanfluid190b. Fluid190aand/or190b(singly or collectively fluid190) can be constructed and arranged to limit undesired variations in rotational velocity ofcore120 and/oroptical assembly130. In some embodiments,fluid190 comprises a gel. In some embodiments,fluid190 comprises a non-Newtonian fluid (e.g. a shear-thinning fluid) or other fluid whose viscosity changes with shear. Alternatively or additionally, fluid190 can comprise a lubricant (e.g. to provide lubrication betweencore120 and shaft110). In some embodiments,fluid190 comprises a shear-thinning fluid, andcore120 is rotated at a rate above 50 Hz, such as a rate above 100 Hz or 200 Hz. At higher rotation rates, iffluid190 comprised a high viscosity Newtonian fluid, the resultant viscous drag during rotation ofcore120 would result in a torsional load oncore120 which would cause it to break before the high rotation could be reached. However, a fluid190 comprising a low viscosity Newtonian fluid is also not desired, as it would not provide sufficient dampening (e.g. would not provide adequate rotational speed control), such as during low-speed (“idle-mode’) imaging. For these reasons, probe100 can comprise a fluid190 that is a relatively high viscosity, shear-thinning (non-Newtonian) fluid, that provides sufficient loading during low speed rotation ofcore120 and, due to its varying viscosity, avoid excessive loading during high speed rotation ofcore120. In some embodiments,fluid190 comprises a shear-thinning fluid whose viscosity changes non-linearly (e.g. its viscosity rapidly decreases with increasing shear rate). In some embodiments,probe100 comprises a reduced gap betweenshaft110 andcore120 along at least a portion of shaft110 (e.g. a portion ofshaft110 proximal to optical assembly130), such as via a space reducing element as described herebelow in reference toFIG. 16. This gap can range from 20 μm to 200 μm (e.g. a constant or varied gap between 20 μm and 200 μm). Fluid190 (e.g. a high viscosity, shear-thinning fluid) can be positioned (at least) in the reduced gap portion ofshaft110. In this configuration, the amount of force applied tocore120 to reduce rotational variation is proportional to the shear stress and the length ofshaft110 in whichfluid190 andshaft110 interact (the “interaction length”). Positioning of this interaction length relatively proximate tooptical assembly130 optimizes reduction of undesired rotational velocity variation of optical assembly130 (e.g. sincecore120 can have low torsional rigidity, dampening sufficiently far fromoptical assembly130 will not provide the desired effect upon optical assembly130).
• In some embodiments,optical assembly130 comprises alens131 with an OD that is greater than the diameter oflumen112 of shaft110 (e.g. greater than the diameter of at least a portion oflumen112 that is proximal to optical assembly130). The OD oflens131 being greater than the diameter oflumen112 preventsoptical assembly130 from translating withinlumen112. For example,lens131 can comprise a relatively large diameter aperture lens, such as to provide a small spot size while collecting large amounts of light (e.g. alens131 with an OD approaching up to 350 μm).Lumen112 can be less than this diameter (e.g. less than 350 μm), such as to allow a reduced OD ofshaft110 proximal to optical assembly130 (e.g. as shown inFIGS. 4, 5, 6, 12, 13 and 16). In embodiments in which the OD ofoptical assembly130 is greater than the diameter oflumen112 at locations proximal tooptical assembly130, the portion ofshaft110 surroundingoptical assembly130 has a larger OD and/or ID than the portions ofshaft110 proximal tooptical assembly130. In these embodiments, bothshaft110 andoptical assembly130 are retracted simultaneously during collection of image data, sincelumen112 has too small a diameter to accommodate translation ofoptical assembly130.
• In some embodiments, fluid190 (e.g. fluid190a) comprises a fluid with a viscosity between 10 Pa-S and 100,000 Pa-S. In these embodiments, fluid190 can be configured to thin to approximately 3 Pa-S at a shear rate of approximately 100 s⁻¹. In some embodiments, fluid190 (e.g. fluid190b) comprises a viscosity between 1 Pa-S and 100 Pa-S, such as a viscosity of approximately 10 Pa-S. In some embodiments,fluid190 is configured to causecore120 to tend to remain centered withinlumen112 ofshaft110 as it rotates (e.g. due to the shear-thinning nature of fluid190). In some embodiments, fluid190acomprises a hydrocarbon-based material and/or silicone. In some embodiments, fluid190bcomprises mineral oil and/or silicone. In some embodiments,probe100 includes one ormore fluids190 in at least the most distal 20 cm ofshaft110.
• In some embodiments, a seal is included inlumen112, sealingelement116, constructed and arranged to provide a seal betweencore120 and the walls of shaft110 (e.g. when positioned withindistal portion119a).Sealing element116 can allow for the rotation ofcore120, while preventing the mixing and/or migrating offluids190aand/or190b(e.g. by resisting the flow of either around seal116). In some embodiments, a sealingelement116 is positioned between 1 mm and200 fromoptical assembly130, such as when sealingelement116 is positioned approximately 3 mm fromoptical assembly130. In some embodiments, sealingelement116 comprises two or more sealing elements, such as two ormore sealing elements116 which slidingly engagecore120 and/oroptical assembly130. In some embodiments,probe100 comprises a sealing element positioned in a proximal portion of shaft110 (e.g. within or proximate connector102), such as sealingelement151 described herebelow in reference toFIG. 7.
• Sealing element116 and/or151 can comprise an element selected from the group consisting of: a hydrogel material; a compliant material; silicone; and combinations of one or more of these. In some embodiments, sealingelement116 and/or151 can comprise a material bonded toshaft110 with an adhesive, or simply an adhesive itself on shaft110 (e.g. a UV cured adhesive or an adhesive configured not to bond with core120).
• In some embodiments,fluid190 is configured to be pressurized, such as is described herein in reference toFIG. 7, such as to reduce bubble formation and/or bubble growth withinfluid190.
• Shaft110 can comprise one or more materials, and can comprise at least a portion which is braided and/or includes one or more liners, such as a polyimide or PTFE liner. In some embodiments, at least thedistal portion119aofshaft110 comprises an OD less than or equal to 0.025″, such as an OD less than or equal to 0.022″, 0.018″, 0.016″, 0.015″ or 0.014″. In some embodiments,shaft110 comprises a material selected from the group consisting of: polyether ether ketone (PEEK); polyimide; nylon; fluorinated ethylene propylene (FEP); polytetrafluoroethylene (PTFE); polyether block amide (Pebax); and combinations of one or more of these. In some embodiments,shaft110 comprises at least a portion including a braid including stainless steel and/or a nickel titanium alloy, such as ashaft110 including a braid positioned over thin walled FEP or PTF. The braided portion can be coated with Pebax or other flexible material. In some embodiments,shaft110 comprises at least a portion (e.g. a proximal portion) that is metal, such as a metal hypotube comprising stainless steel and/or nickel titanium alloy. In some embodiments,shaft110 comprises a first portion that is a metal tube, and a second portion, distal to the first portion, that comprises a braided shaft. In some embodiments,shaft110 comprises at least a portion that comprises a hydrophobic material or other material configured to reduce changes (e.g. changes in length) when exposed to a fluid.
• Viewing portion117 ofshaft110 can comprise one or more materials, and can comprise similar or dissimilar materials to a different portion ofshaft110.Viewing portion117 can comprise a similar ID and/or OD as one or more other portions ofshaft110. In some embodiments,viewing portion117 comprises an ID and/or OD that is larger than an ID and/or OD ofshaft110 atmid portion115 ofshaft110.Viewing portion117 can comprise a similar or dissimilar flexibility as one or more other portions ofshaft110.Viewing portion117 can comprise one or more optically transparent materials selected from the group consisting of: Pebax; Pebax 7233; PEEK; amorphous PEEK; polyimide; glass; sapphire; nylon 12; nylon 66; and combinations of one or more of these.
• In some embodiments, a flexible tip portion is positioned on the distal end ofshaft110, such asspring tip104 shown.Spring tip104 can comprise a length of between 0.5 cm and 5 cm, such as a length of approximately lcm, 2 cm or 3 cm, or a length between 2 cm and 3 cm. At least a portion ofspring tip104 can be made visible to an imaging apparatus, such as by including a radiopaque material such as platinum or other material visible to an X-ray imaging device.Spring tip104 can comprise a core comprising a material such as stainless steel.
• In some embodiments,probe100 and/or other components ofsystem10 comprise one or more markers (e.g. radiopaque or other visualizable markers), sensors, transducers or other functional elements such as:functional elements53a-nofdelivery catheters50;functional element83 ofimplant delivery device80;functional element93 oftreatment device91;functional elements113aand113b(singly or collectivelyfunctional element113, described herebelow) ofshaft110;functional element123 ofcore120;functional element133 ofoptical assembly130;functional element203 ofconsole200; andfunctional element303 ofinjector300.
• In some embodiments,core120 comprises a single mode glass fiber, such as a fiber with an OD between 40 μm and 175 μm, a fiber with an OD between 80 μm and 125 μm, a fiber with an OD between 60 μm and 175 μm, or a fiber with an OD of approximately 110 μm.Core120 can comprise a material selected from the group consisting of: silica glass; plastic; polycarbonate; and combinations of one or more of these.Core120 can comprise a fiber with a coating, such as a polyimide coating.Core120 can comprise cladding material and/or coatings surrounding the fiber, such as are known to those of skill in the art.Core120 can comprise a numerical aperture (NA) of at or above 0.11, such as an NA of approximately 0.16 or 0.20. In some embodiments,core120 can comprise an NA (e.g. an NDA between 0.16 and 0.20) to significantly reduce bend-induced losses, such as would be encountered in tortuous anatomy.System10 can be configured to rotatecore120 in a single direction (uni-directional rotation) or multi-directional (bi-directional rotation).
• In some embodiments,probe100 and other components ofsystem10 are configured to retractcore120 withinshaft110. In these embodiments, probe100 can be configured such that a material (e.g. fluid190) is introduced into and within shaft110 (e.g. betweencore120 and shaft110). The introduced material can be configured to provide a function selected from the group consisting of: index matching; lubrication; purging of bubbles; and combinations of one or more of these.
• In some embodiments,optical assembly130 comprises an OD between 80 μm and 500 μm, such as an OD of at least 125 μm, or an OD of approximately 150 μm. In some embodiments,optical assembly130 comprises a length of between 200 μm and 3000 μm, such as a length of approximately 1000 μm.Optical assembly130 can comprise one or more lenses, such aslens131 shown, such as a GRIN lens and/or a ball lens.Optical assembly130 can comprise a GRIN lens with a focal length between 0.5 mm and 10.0 mm, such as approximately 2.0 mm.Optical assembly130 can comprise one or more reflecting elements, such as reflectingelement132 shown.
• In some embodiments,optical assembly130 comprises alens131 and a reflectingelement132 which is positioned offset fromlens131 via one or moreconnecting elements137 as shown inFIG. 18. Connectingelement137 can comprise a tube (e.g. a heat shrink tube) surrounding at least a portion oflens131 and reflectingelement132. Connectingelement137 can comprise one or more elements selected from the group consisting of: tube; flexible tube; heat shrink; optically transparent arm; and combinations of one or more of these. Connectingelement137 can position reflectingelement132 at a distance of between 0.01 mm and 3.0 mm fromlens131, such as at a distance between 0.01 mm and 1.0 mm. Reflectingelement132 can comprise a partial portion of a larger assembly that is cut or otherwise separated (e.g. cleaved) from the larger assembly during a manufacturing process used to fabricateoptical assembly130. Use of the larger assembly can simplify handling during manufacturing. In some embodiments, theresultant reflecting element132 comprises a shape-optimized reflector. Reflectingelement132 can comprise a segment of wire, such as a gold wire. In these embodiments,lens131 can comprise a GRIN lens, such as a lens with an OD of approximately 150 μm and/or a length of approximately 1000 μm. In some embodiments,lens131 further comprises a second lens, such as a coreless lens positioned proximal to and optically connected to the GRIN lens.
• In some embodiments,imaging probe100 comprises a reduced diameter portion (e.g. a reduced outer and/or inner diameter portion) alongshaft110, at a location proximal tooptical assembly130, such as is shown inFIGS. 4, 5, 6, 12, 13 and 16. In these embodiments,optical assembly130 can comprise an OD that is larger thanlumen112 of shaft110 (e.g. at a location proximal to optical assembly130), such as to provide alarger lens131 for improved imaging capability. In some embodiments,probe100 comprises a space reducing element betweenshaft110 andcore120, such as is described herebelow in reference to elements122 ofFIG. 16.Functional elements113 and/or123 can comprise a space reducing element (e.g. a projection fromshaft110 and/orcore120, respectively).
• Console200 can comprise an assembly,rotation assembly210 constructed and arranged to rotate atleast core120.Rotation assembly210 can comprise one or more motors configured to provide the rotation, such as a motor selected from the group consisting of: DC motor; AC motor; stepper motor; synchronous motor; and combinations of one or more of these. Console200 can comprise an assembly,retraction assembly220, constructed and arranged to retract atleast shaft110.Retraction assembly220 can comprise one or more motors or linear drive elements configured to provide the retraction, such as a component selected from the group consisting of: DC motor; AC motor; stepper motor; synchronous motor; gear mechanism, linear drive mechanism; magnetic drive mechanism; piston; pneumatic drive mechanism; hydraulic drive mechanism; and combinations of one or more of these.Rotation assembly210 and/orretraction assembly220 can be of similar construction and arrangement to those described in applicant's co-pending application U.S. Provisional Application Ser. No. 62/148,355, titled “Micro-Optic Probes for Neurology”, filed Apr. 29, 2015; the content of which is incorporated herein by reference in its entirety for all purposes.
• Console200 can comprise animaging assembly230 configured to provide light to optical assembly130 (e.g. via core120) and collect light from optical assembly130 (e.g. via core120).Imaging assembly230 can include alight source231.Light source231 can comprise one or more light sources, such as one or more light sources configured to provide one or more wavelengths of light tooptical assembly130 viacore120.Light source231 is configured to provide light to optical assembly130 (via core120) such that image data can be collected comprising cross-sectional, longitudinal and/or volumetric information related to the patient site PS or implanted device being imaged.Light source231 can be configured to provide light such that the image data collected includes characteristics of tissue within the patient site PS being imaged, such as to quantify, qualify or otherwise provide information related to a patient disease or disorder present within the patient site PS being imaged.Light source231 can be configured to deliver broadband light and have a center wavelength in the range from 800 nm to 1700 nm. Thelight source231 bandwidth can be selected to achieve a desired resolution, which can vary according to the needs of the intended use ofsystem10. In some embodiments, bandwidths are about 5% to 15% of the center wavelength, which allows resolutions of between 20 μm and 5 μm, respectively.Light source231 can be configured to deliver light at a power level meeting ANSI Class 1 (“eye safe”) limits, though higher power levels can be employed. In some embodiments,light source231 delivers light in the 1.3 μm band at a power level of approximately 20 mW. Tissue light scattering is reduced as the center wavelength of delivered light increases, however water absorption also increases.Light source231 can deliver light at a wavelength approximating 1300 nm to balance these two effects.Light source231 can be configured to deliver shorter wavelength light (e.g. approximately 800 nm light) to traverse patient sites to be imaged including large amounts of fluid. Alternatively or additionally,light source231 can be configured to deliver longer wavelengths of light (e.g. approximately 1700 nm light), such as to reduce a high level of scattering within a patient site to be imaged.
• Imaging assembly230 (or another component of console200) can comprise a fiber optic rotary joint (FORJ) configured to transmit light fromlight source231 tocore120, and to receive light fromcore120. In some embodiments,core120 comprises a fiber with a first numerical aperture (NA), andimaging assembly230 comprises an imaging assembly optical core with a second NA different than the first NA. For example, the first NA (the NA of of core120) can comprise an NA of approximately 0.16 and the second NA (the NA of the imaging assembly optical core) can comprise an NA of approximately 0.11. In some embodiments,system10 comprises anadaptor310 configured to optically connectprobe100 to imaging assembly230 (e.g. a single use or limited use disposable adaptor used in less procedures than imaging assembly230).Adaptor310 can comprise a lens assembly configured to “optically match” (e.g. to minimize coupling losses) different numerical apertures (such as the first and second NAs described hereabove). In some embodiments,adaptor310 comprises a fiber with an NA that is the geometric mean of the two different NAs. In some embodiments,adaptor310 comprises a fiber with an NA that is the arithmetic mean of the two different NAs.
• Rotation assembly210 can be constructed and arranged to rotate core120 (and subsequently one or more components of optical assembly130), at a rotational velocity of approximately 250 rps, or at a rotational velocity between 40 rps and 1000 rps.Rotation assembly210 can be configured to rotatecore120 at a rate between 20 rps and 2500 rps. In some embodiments,rotation assembly210 can be configured to rotatecore120 at a rate up to 25,000 rps. In some embodiments, the rotation rate provided byrotation assembly210 is variable, such as when the rotation rate is varied based on a signal provided by a sensor ofsystem10, such as when one or more offunctional elements53,83,93,113,123,133,203 and/or303 comprise a sensor, andalgorithm240 is used to analyze one or more signals from the one or more sensors. In some embodiments, the sensor signal represents the amount of light collected from tissue or other target. In some embodiments,system10 is configured to vary the rotation rate provided byrotation assembly210 when the sensor signal correlates to a parameter selected from the group consisting of: tortuosity of vessel in which probe100 is placed; narrowing of vessel in which probe100 is placed; presence of clot proximateoptical assembly130; presence of an implanted device proximateoptical assembly130; and combinations thereof. In some embodiments, the rotation rate provided byrotation assembly210 is varied by an operator of system10 (e.g. a clinician). Alternatively or additionally,system10 can vary the rotation rate provided byrotation assembly210 automatically or at least semi-automatically (“automatically” herein), such as an automatic variation of a rotation rate as determined by one or more signals from one or more sensors as described hereabove. In some embodiments, rotation byrotation assembly210 is increased (manually or automatically) whenoptical assembly130 is collecting image data from a target area.
• In some embodiments,rotation assembly210 is constructed and arranged to rotatecore120 at one rate (e.g. at least 150 rps or approximately 250 rps) during image data collection (i.e. an “imaging mode”), and at a different rate (e.g. a slower rate, such as a rate between 30 rps and 150 rps), during a “preview mode”. During preview mode, a “positioning operation” can be performed in whichoptical assembly130 is linearly positioned and/or a flush procedure can be initiated. The positioning operation can be configured to visualize bright reflections (e.g. via one or more implants such as an implanted stent, flow director and/or coils). Alternatively or additionally, the preview mode can be configured to allow an operator (e.g. a clinician) to confirm thatoptical assembly130 has exited thedistal end59 of a surroundingdelivery catheter50. The preview mode can be configured to reduce time and acceleration forces associated withrotating core120 at a velocity to accommodate image data collection (e.g. a rotational velocity of at least 150 rps or approximately 250 rps).
• Retraction assembly220 can be constructed and arranged to retract optical assembly130 (e.g. bycore120 and/or retracting shaft100) at a retraction rate of approximately 40 mm/sec, such as a retraction rate between 3 mm/sec and 500 mm/sec (e.g. between 5 mm/sec and 60 mm/sec, or approximately 50 mm/sec).Retraction assembly220 can be constructed and arranged to perform a pullback of between 20 mm and 150 mm (e.g. a pullback of approximately 50 mm or 75 mm), such as a pullback that is performed in a time period between 0.1 seconds and 15.0 seconds, such as a period between 0.1 and 10 seconds, or a period of approximately 4 seconds. In some embodiments, pullback distance and/or pullback rate are operator selectable and/or variable (e.g. manually or automatically). In some embodiments, the pullback distance and/or pullback rate provided byretraction assembly220 is variable, such as when the pullback distance and/or pullback rate is varied based on a signal provided by a sensor ofsystem10, such as when one or more offunctional elements53,83,93,113,133,203 and/or303 comprise a sensor, andalgorithm240 is used to analyze one or more signals from the one or more sensors. In some embodiments, the sensor signal represents the amount of light collected from tissue or other target. In some embodiments,system10 is configured to vary the pullback distance and/or pullback rate provided byretraction assembly220 when the sensor signal correlates to a parameter selected from the group consisting of: tortuosity of vessel in which probe100 is placed; narrowing of vessel in which probe100 is placed; presence of clot proximateoptical assembly130; presence of an implanted device proximateoptical assembly130; and combinations thereof. In some embodiments, the pullback distance and/or pullback rate provided byretraction assembly220 is varied by an operator of system10 (e.g. a clinician). Alternatively or additionally,system10 can vary the pullback distance and/or pullback rate provided byretraction assembly210 automatically or at least semi-automatically (“automatically” herein), such as an automatic variation of a pullback distance and/or pullback rate as determined by one or more signals from one or more sensors as described hereabove. In some embodiments, pullback distance and/or pullback rate byretraction assembly220 is varied (increased or decreased, manually or automatically) whenoptical assembly130 is collecting image data from a target area.
• In some embodiments,retraction assembly220 and probe100 are configured such that during image data collection,retraction assembly220 retractscore120 without causing translation to shaft110 (e.g. core120 retracts withinlumen112 of shaft110).
• In some embodiments,retraction assembly220 and probe100 can be configured such that during image data collection,retraction assembly220 retractscore120 andshaft110 in unison. In these embodiments,shaft110 can comprise a relatively short viewing window,viewing portion117 surroundingoptical assembly130, sinceoptical assembly130 does not translate withinshaft110. For example, in these embodiments,viewing portion117 can comprise a length less than or equal to 20 mm, less than or equal to 15 mm, less than or equal to 6 mm, or less than or equal to 4 mm, such as when viewingportion117 comprises a length of approximately 3 mm. In some embodiments,viewing portion117 comprises a length between 5 mm and 50 mm, such as a length of approximately 10 mm or approximately 12 mm. In these embodiments in whichoptical assembly130 does not translate withinshaft110,shaft110 diameter (ID and/or OD) can be reduced at locations proximal toviewing portion117, such as when the OD of shaft110 (at least the portion ofshaft110 surrounding and proximate optical assembly), comprises a diameter of less than or equal to 0.025″, 0.016″ or 0.014″. Alternatively or additionally, in these embodiments in whichoptical assembly130 does not translate withinshaft110, portions of the shaft proximal to optical assembly130 (e.g. proximal to viewing portion117) can include a non-transparent construction, such as a braided construction or a construction using materials such as metal tubing (e.g. nitinol or stainless steel hypotube), such as to improve pushability ofprobe100.
• Retraction assembly220 can be configured to minimize formation of bubbles within any fluid (e.g. fluid190) withinshaft110, such as by retractingshaft110 andcore120 in unison, or by retractingcore120 at a precision rate to avoid bubble formation. Whenshaft110 is retracted,proximal portion111acan be configured to be positioned in a service loop.Retraction assembly220 can comprise a translatable slide, androtation assembly210 can be positioned on the translatable slide.
• Retraction assembly220 can comprise a telescoping retraction assembly.Retraction assembly220 can comprise a motor, such as a single use or otherwise sometimes disposable motor, such as a disposable motor that is part of a telescoping retraction assembly.
• In some embodiments,rotation assembly210 can be independently positioned in reference toretraction assembly220. In some embodiments,retraction assembly220 is configured to be positioned closer to the patient than therotation assembly210 is positioned (e.g. whenretraction assembly220 is positioned within 20 cm of a vascular introducer or other patient introduction device through whichprobe100 is inserted). In some embodiments,retraction assembly220 is configured to removably attach to a patient introduction device, such as to connect to a Touhy connector of a vascular introducer through whichprobe100 is inserted, such as adelivery catheter50 described herein.
• In some embodiments,retraction assembly220 receives “motive force” fromconsole200, such as viadrive shaft211 that may be operably attached torotation assembly210 as shown inFIG. 1.
• Console200 can comprise adisplay250, such as a display configured to provide one or more images (e.g. video) based on the collected image data.Imaging assembly230 can be configured to provide an image ondisplay250 with an updated frame rate of up to approximately 250 frames per second (e.g. similar to the rotational velocity of core120).Display250 can provide a 2-D and/or 3-D representation of 2-D and/or 3-D data.
• Console200 can comprise one or more functional elements, such asfunctional element203 shown inFIG. 1.Functional element203 can comprise one or more functional elements such as one or more sensors, transducers and/or other functional elements as described in detail herebelow.
• Console200 can comprise an algorithm, such asalgorithm240 shown, which can be configured to adjust (e.g. automatically and/or semi-automatically adjust) one or more operational parameters ofsystem10, such as an operational parameter ofconsole200,probe100 and/or adelivery catheter50. Alternatively or additionally,algorithm240 can be configured to adjust an operational parameter of a separate device, such asinjector300 orimplant delivery device80 described herebelow. In some embodiments,algorithm240 is configured to adjust an operational parameter based on one or more sensor signals, such as a sensor signal provided by a sensor-based functional element of the present inventive concepts as described herein (e.g. a signal provided by one or more offunctional elements53,83,93,113,123,203 and/or303).Algorithm240 can be configured to adjust an operational parameter selected from the group consisting of: a rotational parameter such as rotational velocity ofcore120 and/oroptical assembly130; a retraction parameter ofshaft110 and/oroptical assembly130 such as retraction velocity, distance, start position, end position and/or retraction initiation timing (e.g. when retraction is initiated); a position parameter such as position ofoptical assembly130; a line spacing parameter such as lines per frame; an image display parameter such as a scaling of display size to vessel diameter; aprobe100 configuration parameter; aninjectate305 parameter such as a saline to contrast ratio configured to determine an appropriate index of refraction; alight source231 parameter such as power delivered and/or frequency of light delivered; and combinations of one or more of these. In some embodiments,algorithm240 is configured to adjust a retraction parameter such as a parameter triggering the initiation of the pullback, such as a pullback that is initiated based on a parameter selected from the group consisting of: lumen clearing;injector300 signal; change in image data collected (e.g. a change in an image, based on the image data collected, that correlates to proper evacuation of blood from around optical assembly130); and combinations of one or more of these. In some embodiments,algorithm240 is configured to adjust aprobe100 configuration parameter, such as whenalgorithm240 identifies (e.g. automatically identifies via an RF or other embedded ID) the attachedprobe100 and adjusts a parameter such as arm path length and/or other parameter as listed above.
• Injector300 can comprise a power injector, syringe pump, peristaltic pump or other fluid delivery device configured to inject a contrast agent, such as radiopaque contrast, and/or other fluids. In some embodiments,injector300 is configured to deliver contrast and/or other fluid (e.g. contrast, saline and/or Dextran). In some embodiments,injector300 delivers fluid in a flushing procedure as described herebelow. In some embodiments,injector300 delivers contrast or other fluid through adelivery catheter50 with an ID of between 5 Fr and 9 Fr, adelivery catheter50 with an ID of between 0.53″ to 0.70″, or adelivery catheter50 with an ID between 0.0165″ and 0.027″. In some embodiments, contrast or other fluid is delivered through a delivery catheter as small as 4 Fr (e.g. for distal injections). In some embodiments,injector300 delivers contrast and/or other fluid through the lumen of one ormore delivery catheters50, while one or moresmaller delivery catheters50 also reside within thelumen52. In some embodiments,injector300 is configured to deliver two dissimilar fluids simultaneously and/or sequentially, such as a first fluid delivered from a first reservoir and comprising a first concentration of contrast, and a second fluid from a second reservoir and comprising less or no contrast.Injector300 can comprise one or more functional elements, such asfunctional element303 shown inFIG. 1.Functional element303 can comprise one or more functional elements such as one or more sensors, transducers and/or other functional elements as described in detail herebelow.
• Implant85 can comprise an implant (e.g. a temporary or chronic implant) for treating one or more of a vascular occlusion or an aneurysm. In some embodiments,implant85 comprises one or more implants selected from the group consisting of: a flow diverter; a Pipeline™ flow diverter; a Surpass™ flow diverter; an embolization coil; a stent; a Wingspan™ stent; a covered stent; an aneurysm treatment implant; and combinations of one or more of these.Delivery device80 can comprise a catheter or other tool used to deliverimplant85, such as whenimplant85 comprises a self-expanding or balloon expandable portion.Implant delivery device80 can comprise a functional element, such asfunctional element83 shown inFIG. 1.Functional element83 can comprise one or more functional elements such as one or more sensors, transducers and/or other functional elements as described in detail herebelow. In some embodiments,system10 comprises aprobe100, one ormore implants85 and/or one or moreimplant delivery devices80, such as is described in applicant's co-pending application U.S. Provisional Application Ser. No. 62/212,173, titled “Imaging System includes Imaging Probe and Delivery Devices”, filed Aug. 31, 2015; the content of which is incorporated herein by reference in its entirety for all purposes. In some embodiments,probe100 is configured to collect data related toimplant85 and/or implant delivery device80 (e.g. implant85 and/orimplant delivery device80 anatomical location, orientation and/or other configuration data), afterimplant85 and/orimplant delivery device80 has been inserted into the patient.
• Treatment device91 can comprise an occlusion treatment or other treatment device selected from the group consisting of: a balloon catheter constructed and arranged to dilate a stenosis or other narrowing of a blood vessel; a drug eluting balloon; an aspiration catheter; a sonolysis device; an atherectomy device; a thrombus removal device such as a stent retriever device; a Trevo™ stentriever; a Solitaire™ stentriever; a Revive™ stentriever; an Eric™ stentriever; a Lazarus™ stentriever; a stent delivery catheter; a microbraid implant; an embolization system; a WEB™ embolization system; a Luna™ embolization system; a Medina™ embolization system; and combinations of one or more of these. In some embodiments,treatment device91 comprises a therapeutic device selected from the group consisting of: stent retriever; embolization coil; embolization coil delivery catheter; stent; covered stent; stent delivery device; aneurysm treatment implant; aneurysm treatment implant delivery device; flow diverter; balloon catheter; and combinations thereof. In some embodiments,probe100 is configured to collect data related to treatment device91 (e.g. treatment device91 location, orientation and/or other configuration data), aftertreatment device91 has been inserted into the patient.Treatment device91 can comprise a functional element, such asfunctional element93 shown inFIG. 1.
• 2^ndImaging device92 can comprise an imaging device such as one or more imaging devices selected from the group consisting of: an X-ray; a fluoroscope such as a single plane or biplane fluoroscope; a CT Scanner; an MM; a PET Scanner; an ultrasound imager; and combinations of one or more of these.
• Functional elements53,83,93,113,123,133,203, and/or303 can each comprise one or more sensors, transducers and/or other functional elements, as described in detail herebelow.
• In some embodiments, afunctional element113 is positioned proximate optical assembly130 (e.g.functional element113bpositioned distal tooptical assembly130 as shown inFIG. 1A, at the same axial location asoptical assembly130 and/or proximal to optical assembly130). In some embodiments,imaging probe100 comprisesfunctional element113ashown inFIG. 1.Functional element113ais shown positioned on a proximal portion ofshaft110, however it can be positioned at anotherprobe100 location such as on, in and/or withinconnector102.Functional elements113aand/or113b(singly or collectively functional element113) can each comprise one or more functional elements such as one or more sensors, transducers and/or other functional elements as described in detail herebelow.
• In some embodiments,functional element53,83,93,113,123,133,203 and/or303 comprise a sensor, such as a sensor configured to provide a signal related to a parameter of asystem10 component and/or a sensor configured to provide a signal related to a patient parameter.Functional element53,83,93,113,123,133,203 and/or303 can comprise one or more sensors selected from the group consisting of: a physiologic sensor; a pressure sensor; a strain gauge; a position sensor; a GPS sensor; an accelerometer; a temperature sensor; a magnetic sensor; a chemical sensor; a biochemical sensor; a protein sensor; a flow sensor such as an ultrasonic flow sensor; a gas detecting sensor such as an ultrasonic bubble detector; a sound sensor such as an ultrasound sensor; and combinations of one or more of these. In some embodiments,functional element53,83,93,113,123,133,203 and/or303 can comprise one or more physiologic sensors selected from the group consisting of: a pressure sensor such as a blood pressure sensor; a blood gas sensor; a flow sensor such as a blood flow sensor; a temperature sensor such as a blood or other tissue temperature sensor; and combinations of one or more of these. In some embodiments,algorithm240 is configured to process the signal received by a sensor, such as a signal provided by a sensor as described herein. In some embodiments,functional element53,83,93,113,123 and/or133 comprises a position sensor configured to provide a signal related to a vessel path (e.g. a vessel lumen path) in three dimensions. In some embodiments,functional element53,83,93,113,123 and/or133 comprises a magnetic sensor configured to provide a signal for positioningoptical assembly130 relative to one or more implanted devices (e.g. one ormore implants85 described herein comprising a ferrous or other magnetic portion). In some embodiments,functional element53,83,93,113,123 and/or133 comprises a flow sensor, such as a flow sensor configured to provide a signal related to blood flow through a blood vessel of the patient site PS (e.g. blood flow through a stenosis or other partially occluded segment of a blood vessel). In these embodiments,algorithm240 can be configured to assess blood flow (e.g. assess the significance of an occlusion), such as to provide information to a clinician regarding potential treatment of the occlusion. In some embodiments,optical assembly130 comprisesfunctional element113, such as whenoptical assembly130 is constructed and arranged as a sensor that provides a signal related to blood flow. In some embodiments,functional element53,83,93,113,123 and/or133 comprises a flow sensor configured to provide a signal used to co-register vessel anatomic data to flow data, which can be used to provide pre and post intervention modeling of flow (e.g. aneurysm flow), assess risk of rupture and/or otherwise assess adequacy of the intervention. In some embodiments,functional element53,83,93,113,123 and/or133 comprises an ultrasound sensor configured to provide a signal (e.g. image or frequency data) which can be co-registered with near field optical derived information provided byoptical assembly130. In some embodiments,functional element53,83,93 and/or113 are configured to be deployed by their associated device, such as to implant the functional element (e.g. a sensor-based functional element) into the patient. The implantablefunctional element53,83,93 and/or113 can comprise microchip and/or MEMS components. The implantablefunctional element53,83,93 and/or113 can comprise at least a portion that is configured to be visualized (e.g. by image data collected byprobe100 and/or a separate imaging device such assecond imaging device92.
• In some embodiments,functional element53,83,93,113,123,133,203 and/or303 comprise one or more transducers selected from the group consisting of: a heating element such as a heating element configured to deliver sufficient heat to ablate tissue; a cooling element such as a cooling element configured to deliver cryogenic energy to ablate tissue; a sound transducer such as an ultrasound transducer; a vibrational transducer; and combinations of one or more of these.
• In some embodiments,functional element53,83,93 and/or113 comprises a pressure release valve configured to prevent excessive pressure from accumulating in the associated device. In some embodiments,functional element53,83,93 and/or113 comprises one or more sideholes, such as one or more sideholes used to deliver a fluid in a flushing procedure as described herein.
• In some embodiments,functional element53,83,93,113,123,133,203 and/or303 comprise a visualizable marker, such as whenfunctional element53,83,93 and/or113 comprise a marker selected from the group consisting of: radiopaque marker; ultrasonically reflective marker; magnetic marker; ferrous material; and combinations of one or more of these.
• Probe100 is configured to collect image data, such as image data collected during rotation and/or retraction ofoptical assembly130.Optical assembly130 can be rotated by rotatingcore120.Optical assembly130 can be retracted by retractingshaft110.Optical assembly130 can collect image data while surrounded by a portion of a shaft of a delivery catheter50 (e.g. when within atransparent segment57 of a delivery catheter) and/or when there is nocatheter50 segment surrounding optical assembly130 (e.g. whenoptical assembly130 has been advanced beyond the distal ends59 of alldelivery catheters50 into whichprobe100 is inserted).
• During collection of image data, a flushing procedure can be performed, such as by delivering one or more fluids, injectate305 (e.g. as propelled byinjector300 or other fluid delivery device), to remove blood or other somewhat opaque material (hereinafter non-transparent material) proximate optical assembly130 (e.g. to remove non-transparent material betweenoptical assembly130 and a delivery catheter and/or non-transparent material betweenoptical assembly130 and a vessel wall), such as to allow light distributed fromoptical assembly130 to reach and reflectively return from all tissue and other objects to be imaged. In these flushing embodiments,injectate305 can comprise an optically transparent material, such as saline.Injectate305 can comprise one or more visualizable materials, as described herebelow.Injectate305 can be delivered byinjector300 as described hereabove.
• Flush rates required for providing clearance aroundoptical assembly130 can scale inversely with the viscosity of the flush medium. This mathematical relationship can be driven by the downstream draining of the flush medium in the capillary bed. If the capillary bed drains slowly, it is easier to maintain the upstream flush at a pressure at or slightly above native blood pressure, such that fresh blood will not enter the vessel being imaged (e.g. at a location proximate optical assembly130). Conversely, if the capillary bed drains rapidly, the flush rate will need to increase correspondingly. Since saline (a standard flush medium) has a viscosity about ⅓ that of blood (e.g. 1 Cp vs 3.3 Cp), roughly three times normal flow rate will be required to clear a vessel (in the area proximate optical assembly130), and such flow rates can pose a risk to vessel integrity. As an alternative, contrast media (e.g. radiopaque contrast media) can be used for flushing. Contrast material has a high viscosity (due to its high iodine concentrations, typically a concentration of approximately 300 mg/ml).System10 can comprise a flushing fluid comprising contrast, such as contrast with a concentration between 50 mg/ml to 500 mg/ml of iodine (e.g. correlating to viscosities approximately two to five times that of blood).System10 can comprise a flushing fluid (e.g. a radiopaque or other visualizable flushing fluid) with a viscosity between 1.0 Cp and 20 Cp (e.g. at a temperature of approximately 37° C.).
• Alternative or in addition to its use in a flushing procedure,injectate305 can comprise material configured to be viewed bysecond imaging device92, such as when injectate305 comprise a contrast material configured to be viewed by asecond imaging device92 comprising a fluoroscope or other X-ray device; an ultrasonically reflective material configured to be viewed by asecond imaging device92 comprising an ultrasound imager; and/or a magnetic material configured to be viewed by asecond imaging device92 comprising an MRI.
• Injectate305 can be delivered by one or more delivery catheters50 (e.g. in the space between afirst delivery catheter50 and an inserteddelivery catheter50, or in the space between adelivery catheter50 and an inserted probe100).Injectate305 delivered in a flushing procedure (orother injectate305 delivery procedure) can be delivered out thedistal end59 of a delivery catheter50 (e.g. adistal end59 positioned proximal to optical assembly130), such as is described in applicant's co-pending U.S. Provisional Application Ser. No. 62/212,173, titled “Imaging System includes Imaging Probe and Delivery Devices”, filed Aug. 31, 2015, the content of which is incorporated herein by reference in its entirety for all purposes. Alternatively or additionally, anydelivery catheter50 can comprise one or more sideholes passing through a portion of the associatedshaft51, such assideholes58 shown positioned on a distal portion ofdelivery catheter50c. In some embodiments, adelivery catheter50 comprises a microcatheter comprising sideholes58 positioned on a distal portion, such as a microcatheter with an ID less than 0.027″ (e.g. a microcatheter with an ID between 0.016″ and 0.027″ or an ID between 0.021″ and 0.027″). In some embodiments, flushing fluid is delivered towardsoptical assembly130 from bothsideholes58 and from thedistal end59 of adelivery catheter50.Sideholes58 can be constructed and arranged to allow a flushing fluid to pass from withinshaft51 and through thesideholes58, such as when a separate shaft is inserted within the delivery catheter50 (e.g. ashaft51 of anadditional delivery catheter50 or theshaft110 of probe100). Delivery of flushing fluid throughsideholes58 and/or the distal end of thedelivery catheter50 can be performed to clear blood from an area from a luminal segment surroundingoptical assembly130, such as during collecting of image data.
• In some embodiments, the delivery ofinjectate305 during a flushing procedure is based on a parameter selected from the group consisting of: a pre-determined volume of injectate to be delivered; a pre-determined time during which injectate is delivered; an amount of time of delivery including a time extending from a time prior to retraction ofshaft110 that continued until the collecting of the image data has been completed (e.g. completion of retraction of shaft110); and combinations of one or more of these. In some embodiments,injector300 delivers fluid in a flushing procedure with an approximate flow profile selected from the group consisting of: contrast (e.g. between 20% and 100% contrast that can be mixed with saline) at 5 ml/second for 6 seconds (e.g. for imaging of a carotid artery including 4 seconds of collecting image data); contrast (e.g. between 20% and 100% contrast that can be mixed with saline) at 4 ml/second for 6 seconds (e.g. for imaging of a vertebral artery including 4 seconds of collecting image data); and combinations of one or more of these. In some embodiments, a flushing procedure comprises delivery of injectate305 (e.g. via one or more delivery catheters50) for between 2 seconds to 8 seconds, such as a delivery of injectate for approximately 4 seconds (e.g. to purge blood or other non-transparent fluid from a luminal segment of a blood vessel or other area surroundingoptical assembly130 during collection of image data from a patient site PS). In similar flushing procedures,injectate305 can be delivered at a rate between 3 ml/second and 9 ml/second (e.g. approximately 6 ml/sec via one or more delivery catheters50), to purge non-transparent material.
• In these flushing procedures,injectate305 can comprise a transparent fluid selected from the group consisting of: saline; contrast; Dextran; and combinations of one or more of these. In some embodiments, the volume ofinjectate305 delivered and/or the time ofinjectate305 delivery during a flushing procedure is determined by a parameter selected from the group consisting of: type of procedure being performed; diameter of vessel in whichoptical assembly130 is positioned; length of pullback; duration of pullback; and combinations of one or more of these. In some embodiments,injectate305 is delivered during a flushing procedure by a delivery catheter with an ID greater than 0.027″ (e.g. afirst delivery catheter50 whosedistal end59 is more proximal than asecond delivery catheter50 inserted into the first delivery catheter50). In some embodiments,injectate305 is delivered viamultiple lumens52 in associated multiple delivery catheters50 (e.g. in the space between two or more pairs ofdelivery catheters50 arranged to slidingly receive each other in a sequential fashion).
• In some embodiments, injectate comprises a first fluid delivered in a first portion of a flushing procedure (e.g. a fluid comprising saline and/or a fluid comprising no or minimal contrast), and a second fluid including contrast (e.g. a second fluid comprising saline and contrast), such as to limit the amount of contrast delivered to the patient during the flush procedure. In these embodiments,injector300 can comprise two reservoirs (as described hereabove), such as a first reservoir for supplying the first fluid and a second reservoir for supplying the second fluid. When comprised of two reservoirs,injector300 can be configured to deliver the fluids in each reservoir at different rates, such as to achieve different pressures and/or to provide flushing through different catheters with different IDs.
• As described herein,optical assembly130 can be rotated (e.g. via rotation of core120) and retracted (e.g. via retraction ofshaft110 by retraction assembly220) during collection of image data, such as a rotation combined with retraction to create a 3D image of the patient site PS. In some embodiments,optical assembly130 is rotated at a rate between 40 rps and 1000 rps, such as a rate of approximately 250 rps. In some embodiments,optical assembly130 is rotated at a first rate during an imaging mode, and a second rate during a preview mode (imaging mode and preview mode each described hereabove). In some embodiments, the retraction ofoptical assembly130 spans of distance of between 1 cm and 15 cm, such as a retraction of approximately 4 cm. In some embodiments,optical assembly130 is retracted at a rate of between 1 mm/sec and 60 mm/sec. In some embodiments, the retraction ofoptical assembly130 comprises a retraction of approximately 7.5 cm over 4 seconds and/or a retraction rate of approximately 20 mm/sec. In some embodiments, retraction ofoptical assembly130 comprises a resolution of between 5 μm and 20 μm axially and/or a resolution between 20 μm and 100 μm longitudinally. The longitudinal resolution is governed by two factors: the spot-size (light beam cross-section) at the tissue surface being imaged and the spacing between successive rotations ofoptical assembly130 during retraction. For a rotation rate of 100 rps and a pullback rate of 22 mm/sec, a pitch of 200 μm between rotations results. In these configurations, a spot size between 20 μm and 40 μm would result in collecting image data which under-samples the objects being imaged.System10 can be configured to more closely match spot size with pitch, such as by correlating spot size with rotation rate and/or pullback rate.
• In some embodiments,imaging system10 is constructed, arranged and used to create an image as described in applicant's co-pending U.S. Provisional Application Ser. No. 62/212,173, titled “Imaging System includes Imaging Probe and Delivery Devices”, filed Aug. 31, 2015; the content of each of which is incorporated herein by reference in its entirety for all purposes.
• In some embodiments,system10 is configured to assist in the selection, placement and/or use of atreatment device91.Treatment device91 can comprise a stent retriever configured to remove thrombus or other occlusive matter from a patient, such as when imagingprobe100 images the anatomy and/or thetreatment device91 to produce anatomical information (e.g. used to select the size or other geometry of the stent retriever), visualize the stent retriever at the occlusive site (e.g. to position treatment device91), and or visualize occlusive matter (e.g. thrombus) engaged with and/or not removed by thetreatment device91. In some embodiments,system10 is configured to quantify a thrombus volume, such as a thrombus to be removed by atreatment device91. Thrombus visualized bysystem10 can comprise thrombus selected from the group consisting of: residual thrombus in acute stroke; thrombus remaining after a thrombus removal procedure; thrombus present after flow diverter implantation; and combinations thereof.
• In some embodiments,system10 is configured to provide anatomical information to be used to select a site of implantation and/or to select a particular implantable device to be implanted in the patient, such asimplant85 ofsystem10 described hereabove.System10 can be configured to image at least one perforator artery of the patient, such as to image one, two or more perforator arteries of at least 50 μm in diameter.Implant85 can be implanted in the patient viaimplant delivery device80, such as whenimplant85 comprises a stent and/or a flow diverter.System10 can be configured to perform a function selected from the group consisting of: detect and/or quantifyimplant85 apposition (e.g. a stent or flow diverter malapposition); provide quantitative and/or qualitative information regarding the size and/or placement of animplant85 to be implanted in a patient, such as information related to perforator location; perforator geometry, neck size and/or flow diverter mesh density; and combinations of one or more of these.System10 can be configured to provide information related to animplant85 parameter selected from the group consisting of: porosity; length; diameter; and combinations thereof.System10 can be configured to provideimplant85 porosity information comprising the porosity of one or more portions ofimplant85, such as a portion to be positioned proximate a sidebranch of a vessel in which implant85 is implanted.System10 can be configured to provide porosity information based on a wire diameter ofimplant85.System10 can be configured to provide information related to the implantation (e.g. implantation site or device information) of asecond implant85 to be implanted in the patient. In these embodiments in which two implanteddevices85 are used, the first and second implanted devices can comprise similar or dissimilar devices (e.g. a stent and a flow diverter, two stents or two flow diverters).System10 can be configured to collect image data during deployment of one ormore implants85.System10 can be configured to collect image data used to modify an implanted device (e.g. during and/or after implantation), such as to modify the porosity of implant85 (e.g. via atreatment device91 comprising a balloon catheter used to adjust the porosity of a partially or fully implanted implant85).
• Imaging conventionally inaccessible areas of the body (e.g. coronary arteries, neurovascular arteries, the endocrine system, pulmonary airways, etc.) using specialized catheters has been in use for several decades. Even so, products for these applications are still being widely developed as technological advances allow higher resolution, new modalities (e.g. spatially-resolved spectroscopy), and lower cost probes to be realized. Limitations and other issues with the current catheters are described herebelow. Such imaging catheters commonly utilize high-speed rotation of distally-located optics to create a cross sectional view of a body lumen since reduced diameter imaging catheters generally precludes the use of conventional optics or so-called coherent fiber bundles. Rather than creating a multi-pixel conventional ‘snapshot’, the image with rotating optics is built up one or two pixels at a time by scanning a single imaging spot, similar to the raster scan employed by older CRT's. This rotation may be coupled with a longitudinal motion (‘pull-back’) to create a spiral scan of the artery or lumen, which can be rendered as a 3-D image. The majority of currently available imaging catheters have a distally located imaging element, connected optically or electrically to a proximal end. The imaging element is attached to a mechanical transmission that provides rotation and pullback to occur. Recently, advances in micro-motor technology can supplant the mechanical transmission with distally located actuation, but pullback is still required. However, these motors are expensive and relatively large (available designs do not allow probes below 1 mm OD to be constructed).
• There are a number of commercially available “torque shafts” which are miniature wire-wound tubes intended to transmit torque over a long and flexible shaft. Such devices are now commonly used in intravascular ultrasound (IVUS) procedures as well as OCT procedures. Imaging probes combined with torque shafts perform rotational scanning in coronary arteries for example. Generally however, these devices are approximately 0.8 to 1.3 mm in OD, (2.4 Fr to 4 Fr) and are thus 2 to 4 times larger than the devices required by neurological applications. Presently, such torque wires are not scalable to the sizes required to permit the construction of scanning imaging catheters less than 0.7 mm in OD.
• Since optical imaging in arteries necessitates the clearing of obfuscating blood, usually with a flush solution, the imaging catheter diameter becomes critically important in smaller or obstructed vessels (e.g. due to use of smaller guides). Since it is often diseased or obstructed vessels that require imaging for diagnosis and treatment,imaging probe100 can be designed for a small diameter (e.g. an OD less than or equal to 0.025″, 0.016″ or 0.014″).
• As has been previously disclosed (Petersen, et al U.S. Pat. No. 6,891,984 [the '984 patent]; Crowley U.S. Pat. No. 6,165,127 [the '127 patent], the content of each of which is incorporated herein by reference in its entirety for all purposes), using a viscous fluid located at the distal region of the imaging catheter is provided to prevent twisting.
• Achieving uniform rotational scanning at the distal tip of a single fiber imaging catheter, while maintaining an overall device size less than 500 μm in OD is a significant challenge. Because it is currently impractical to add a motor to the distal tip that is sized less than 1 mm in OD (see Tsung-Han Tsai, Benjamin Potsaid, Yuankai K. Tao, Vijaysekhar Jayaraman, James Jiang, Peter J. S. Heim, Martin F. Kraus, Chao Zhou, Joachim Hornegger, Hiroshi Mashimo, Alex E. Cable, and James G. Fujimoto; “Ultrahigh speed endoscopic optical coherence tomography using micro-motor imaging catheter and VCSEL technology”, Biomed Opt Express. 2013 Jul. 1; 4(7): 1119-1132), with the attendant wires and size issues, a way must be found to apply torque to the proximal end and transmit the torque to the distal tip (which may be as much as three meters away in some clinical applications) while maintaining uniform rotational speed. Uniform speed is paramount to image fidelity as non-uniform rotation can lead to image smearing and severe distortions (SeeFIG. 3). If the extremely low inherent rotational stiffness of a glass fiber is considered, the issues of uniformly spinning the distal tip by driving the proximal end can be appreciated. Uniform rotation is critically important in endoscopic techniques in order to obtain accurate circumferential images. The term ‘NURD’ (non-uniform rotational distortion) has been coined in the industry to describe these deleterious effects.
• An example of distortion caused by non-uniform rotational distortion (NURD) is shown inFIG. 3. The solid curve is a simulated perfectly round artery, 4 mm in diameter. The curve with square data points is the image of the same arterial wall with NURD. In this case, the catheter rotation is slowed by 50% over a small portion of the cycle, and sped up by 50% in another portion, such that the average distal rotational speed matches the proximal rotational speed (as it must, otherwise rapidly accumulating twist would cause thecore120 to break). It can be seen that this NURD can lead to significant measurement errors. Theimaging probe100 and other components ofsystem10 are configured to reduce these types of distortions.
• The '127 patent discloses the use of a viscous fluid located inside the bore of an ultrasound catheter. The purpose of the fluid is to provide loading of a torque wire such that the wire enters the regime of high torsional stiffness at moderate spin rates. As described in the '127 patent, this fluid is housed within a separate bore formed inside the main catheter, increasing the overall size of the device. The fluid does not contact the imaging tip, nor does the ultrasound energy propagate through this fluid. This approach also requires the use of a torque wire, limiting the achievable reduction in size needed. In the imaging probe of the present inventive concepts, one or more viscous fluids (e.g. one or more fluids190) can be provided to deliberately cause twisting (i.e. winding) ofcore120. The twisting can comprise dynamic twisting that changes with total (i.e. end-to-end) frictional load (torque) ofprobe100, to result in a relatively constant rotational rate. Probe100 can be configured such that the amount of twisting changes during a pullback of one or more portions of probe100 (e.g. a pullback ofcore120 and/or a pullback ofcore120 and shaft110).
• The '984 patent utilizes a viscous fluid with a high index of refraction to simultaneously reduce refractive effects at the curved sheath boundary as well as provide viscous loading to allow an optical fiber to be the torque transmitter. This configuration allows a certain reduction in size. However, the '984 patent fails to describe or disclose a mechanism for confining the fluid at the distal tip within the geometry constraints; unavoidable migration of this fluid during transport and storage will cause unavoidable loss of performance. Similarly, the '984 patent fails to address issues that could arise during pullback of the internal fiber which will cause voids to form in the viscous fluid, these voids causing relatively large optical effects (so-called ‘bubble-artifacts’, see, for example, “Expert review document on methodology, terminology, and clinical applications of optical coherence tomography: physical principles, methodology of image acquisition, and clinical application for assessment of coronary arteries and atherosclerosis”, Francisco Prati, et al, European heart Journal, Nov. 4, 2009). In some embodiments,probe100 is configured to rotatecore120 in a single direction (i.e. unidirectional) during use. In some embodiments,probe100 comprises a torque shaft withinshaft110 and frictionally engaged withcore120, such astorque shaft110bdescribed herebelow.Torque shaft110bcan extend from the proximal end ofprobe100 to a location proximal tooptical assembly130, such as a torque shaft with a distal end that is located at least 5 cm fromoptical assembly130, or a distal end that is located proximal to the most proximal location ofshaft110 that is positioned within the patient.
• A liquid, gel or other fluid-filled (e.g. and sealed)imaging probe100 has the advantage that it does not require purging (e.g. to remove air bubbles). The fluid190aor190bcan be configured as a lubricant, reducing friction betweencore120 andshaft110. In embodiments in whichcore120 is pulled back relative toshaft110 to obtain an image, a void is created at the end ofcore120 that can be filled with liquid, gel or other fluid (e.g. fluid190).
• It is difficult for fluid to “fill in” this region as it must be provided from the proximal end ofshaft110 and travel the length of thecore120. Bubbles are likely to form here as a low pressure can be generated. In embodiments of the present inventive concepts, rather than retracting thecore120 withinshaft110, theentire imaging probe100 is pulled back during image data collection (i.e.core120 andshaft110 are retracted in unison without relative axial motion between the two). Since theshaft110 moves along with thecore120, the presence of a low-pressure region at the end of the imaging core is eliminated or at least mitigated.
• As shown inFIG. 4, such “mutual” motion ofshaft110 andcore120 allowsshaft110 to have a larger diameter aroundoptical assembly130, as relative motion betweenoptical assembly130 andshaft110 is avoided. A larger diameter optical assembly130 (e.g. a larger diameter lens of optical assembly130) provides collection of more light, which can correlate to a brighter image. This configuration can also provide a lens ofoptical assembly130 that has a focal length that is positioned farther away from the OD (i.e. outer surface) ofshaft110 surroundingoptical assembly130, improving distal image quality. Alternatively or additionally, and also as shown inFIG. 4,optical assembly130 can comprise an OD that is larger than an ID of at least a portion ofshaft110 proximal tooptical assembly130. In these embodiments,optical assembly130 andshaft110 can be retracted simultaneously during collection of image data from a target area.
• In some embodiments, theshaft110 wall is relatively thicker over a majority of its length as compared to a thinner wall ofshaft110 at a distal portion of shaft110 (e.g. thinner at ashaft110 portion proximate optical assembly130). Such a configuration allows for improved longitudinal and torsional control for positioning ofimaging probe100. In some embodiments,shaft110 can comprise a stiffened portion positioned aboutoptical assembly130, such as a stiffened segment ofshaft110 comprising: a different (stiffer) wall material; a braided shaft portion; and or a stiffening element (e.g. a wire embedded in the wall of shaft110). The stiffened distal portion ofshaft110 can correlate to a thinner wall, which in turn correlates tooptical assembly130 comprising larger optical components (e.g. one or more larger diameter lenses), for example without having to increase the OD ofshaft110 surroundingoptical assembly130. In some embodiments,shaft110 has varying mechanical properties along its length (e.g. a stiffened proximal segment for “push-ability”), and a gradually decreasing stiffness distally (e.g. to improve deliverability and safety as advanced into tortuous anatomy).
• Also as shown inFIG. 4,optical assembly130 can comprise alens131 and a reflecting element132 (e.g. to “turn” the light). Reflectingelement132 is configured such thatoptical assembly130 is asymmetrical. Whenoptical assembly130 is spun at high speed, the presence of viscous liquids or other viscous fluids in the optical path surroundingoptical assembly130 could, in some cases, cause cavitation in the region behindreflector132. As shown inFIG. 5, in some embodiments,probe100 includes a first fluid, fluid190athat surroundscore120, and a second, different fluid, fluid190b, that surroundoptical assembly130, such thatfluid190acan be configured to provide a first function (e.g. prevent or at least reduce undesired rotational variances of core120), whilefluid190bprovides a second function (e.g. prevent or at least reduce cavitation about optical assembly130). In some embodiments, the viscosity offluid190bcan be selected to be relatively low viscosity, such as to minimize cavitation, while the viscosity offluid190acan be selected to be relatively high (e.g. at least more viscous thanfluid190b) to optimize uniformity in the rotational speed.
• In neurological placement,imaging probe100 is usually placed into a femoral vessel of the patient. There is significant tortuosity in the vasculature proximal to a neurological imaging area, starting with the carotid artery take off from the aorta. In some embodiments, the use of ahigh viscosity fluid190ain the mid and/or proximal section ofimaging probe100 allows the fluid190ato provide the additional function of lubricating thespinning core120 in the shaft110 (e.g. lubrication of benefit due to the high tortuosity in whichimaging probe100 is placed). The reduced friction that results reduces the stress on thecore120, and allows smoother motions over any discontinuities inshaft110 orcore120.Fluid190 can be configured to provide sufficient lubrication or other advantageous parameter to eliminate or at least reduce (“reduce” herein) adverse effects that would otherwise occur asprobe100 is positioned in tortuous anatomy (e.g. whendistal portion119ais positioned proximate and distal to the carotid artery). In these embodiments, fluid190 can comprise a high viscosity fluid.
• Additionally, the presence of ahigh viscosity fluid190ahelps maintain thelower viscosity fluid190bin the distal end ofshaft110 prior to use, as thehigher viscosity fluid190ainshaft110 operates as a barrier, and reduces the likelihood offluid190bmigration from the imaging region aboutoptical assembly130 prior to use (e.g. during sterilization and shipping of imaging probe100). In some embodiments, a sealing element, such as sealingelement116, is positioned between two or moredifferent fluids190. Alternatively, no separating element may be present, such as when one or more of thefluids190 comprise a gel configured not to mix with a neighboringfluid190.
• In some embodiments,imaging probe100 includes an inertial assembly comprising an impeller, propeller or other inertia-based element configured to reduce undesired variances in rotational speed ofoptical assembly130, such as is shown inFIG. 6.Imaging probe100 comprisesimpeller182 that is attached to thecore120. Drag onimpeller182 “winds up”core120 and decreases unintended or otherwise undesired variances in rotational velocity of the fiber.Impeller182 operates to spin the fluid190 betweenshaft110 andoptical assembly130. Theimpeller182 blades form drag, which due to its symmetry around its rotational axis, remains uniform through the rotation. In some embodiments, the radial extending ends ofimpeller182 intentionally contact an inner wall ofshaft110, to alternatively or increasingly provide drag.Impeller182 can comprise one or more projections fromcore120, such as projections that frictionally engageshaft110 and/or otherwise cause shear force that applies a load tocore120 during rotation.Impeller182 can comprise one or more projections fromshaft110, such as projections that frictionally engagecore120 and/or otherwise cause shear force that applies a load tocore120 during rotation.
• Impeller182 can be configured to cause wind-up loading ofcore120.Impeller182 can be configured to frictionally engage fluid190 and/orshaft110 during rotation ofcore120.Impeller182 can comprise a component selected from the group consisting of: turbine; vane-type micro-structure; flywheel; and combinations of one or more of these.
• Liquid, gel or other fluid positioned insideshaft110 can have a tendency to form bubbles. If these bubbles are in the optical path they will reduce the light transmission. In some embodiments, fluid190aand/orfluid190b(singly or collectively fluid190) can be pressurized (e.g. to a pressure of 100 psi or above) to prevent or at least reduce the size of any bubbles inshaft110, such as is described herein in reference toFIG. 7.
• Small tire inflators are commonly used for filling bicycle tires. They are available in sizes smaller than 1 inch, which is suitable for this application. These and similarly configured inflators can provide pressures up to and beyond 100 psi, which when applied tofluid190 can significantly reduce the bubble size. Assuming a bubble size at atmospheric pressure is to be 0.1 microliters, the bubble size at 100 psi can be calculated as:
• 
  V_p=V_aP_a/P_p
• where:
• V_p=Bubble volume under pressure
• V_a=Bubble volume at atmospheric pressure (e.g. 0.1 μL)
• P_a=Atmospheric pressure (14.7 PSI)
• P_p=Pressurizing device pressure (e.g. 100 psi)
• Under pressurization, the bubble volume decreases from 0.1 μL to 0.0147 μL. The corresponding bubble diameter is reduced from 0.022″ to 0.011″, which will mitigate or eliminate deleterious effects on the optical beam.
• FIG. 7 is a sectional view of an imaging probe including a pressurization system, consistent with the present inventive concepts.Imaging probe100 comprisesshaft110 withproximal end111,lumen112,core120 andoptical connector102, each of which can be of similar construction and arrangement as those described hereabove in reference toFIG. 1.Imaging probe100 can include pressurization assembly183 (e.g. a pressurized gas canister) which can be fluidly connected to lumen112 via valve184 (e.g. a one way check valve). In some embodiments, eachimaging probe100 is provided with apressurization assembly183. Alternatively, asingle pressurization assembly183 can be reused (e.g. used onmultiple imaging probes100 in multiple clinical procedures). In some embodiments,pressurization assembly183 can be pre-attached toshaft110, or separated and attachable. In some embodiments,pressurization assembly183 can be operably attached and/or activated just prior to the time of clinical use ofimaging probe100, such as to pressurize fluid withinlumen112 orother imaging probe100 internal location, such as to reduce the size of one or more gas bubbles in a fluid, such asfluid190 described herein.
• In some embodiments, at a location near toproximal end111 ofshaft110, sealing element151 (e.g. a compressible O-ring) is positioned betweencore120 andshaft110.Shaft110 and sealingelement151 can be constructed and arranged to maintain a relative seal aslumen112 is pressurized (e.g. as described above), while allowingcore120 to rotate withinshaft110 and sealingelement151.Sealing element151 can provide a seal during rotation ofcore120 withinshaft110. Retraction ofshaft110 andcore120 simultaneously during imaging, as described herein, simplifies the design of sealingelement151. In some alternative embodiments,core120 is retracted withinshaft110, and sealingelement151 is configured to maintain a seal during that retraction.
• In some embodiments, at least a portion ofshaft110 is configured to radially expand asfluid190 is pressurized, such as is shown inFIGS. 15A-C.Pressurization assembly183 is attached toconnector102 such thatfluid190 can be introduced and/or pressurized into and/or withinshaft110. InFIG. 15A,proximal portion111aofshaft110 is expanded (e.g. lumen112 is expanded in the region ofproximal portion111a). InFIG. 15B,proximal portion111aandmid portion115 ofshaft110 are expanded. InFIG. 15C,proximal portion111a,mid portion115 anddistal portion119aare expanded. In these embodiments,system10 can be configured to rotatecore120 aftershaft110 has been fully expanded as shown inFIG. 15C. Expansion ofshaft110 can create and/or increase space betweencore120 and the inner wall ofshaft110. In some embodiments,shaft110 remains at least partially expanded (e.g. shaft110 has been plastically deformed) when the pressure offluid190 is decreased (e.g. to atmospheric pressure).Shaft110 can be configured to expand to a first diameter (ID and/or OD) whenfluid190 is pressurized to a first pressure, and to expand to a second, larger diameter, when fluid190 is pressurized to a second, higher pressure. In some embodiments,shaft110 is configured to become more rigid as the pressure offluid190 increases.
• There can be two attachments from probe100 (e.g. a disposable catheter) to the non-disposable components ofsystem10. One is attached to shaft110 (a non-rotating shaft) and the other tocore120. Attachment ofimaging probe100 to console200 can comprise two functional attachments. One attachment comprises attachment ofshaft110 to a retraction assembly, such asretraction assembly220 described herein, such that shaft110 (and optic assembly130) can be retracted during collection of image data. Another attachment comprises attachingcore120 to a rotational assembly, such asrotation assembly210, such thatcore120 can be rotated during collection of image data. Both attachments can be retracted together during collection of image data. The attachment ofcore120 makes the optical connection betweencore120 and an imaging assembly (e.g. imaging assembly230 described herein) and can provide the motive power to rotate core120 (e.g. an attachment to rotation assembly210).
• The imaging system and associated imaging probes of the present inventive concepts provide enhanced compatibility with traditional therapeutic catheters, such as those used in neurological procedures as described herein.
• Stent retrieval devices (also referred to as “stent retrievers”) are used for endovascular recanalization. While the rate of successful revascularization is high, multiple passes of the stent retrieval device are often required to fully remove the clot, adding to procedure times and increasing likelihood of complications. The addition of imaging to a stent retrieval procedure has the potential to reduce both procedure time and complications. InFIGS. 8-11,system10 comprisesimaging probe100 and a therapeutic device,treatment device91. Whiletreatment device91 is shown as a stent retriever, other therapeutic devices would be applicable, such as atreatment device91 selected from the group consisting of: stent retriever; embolization coil; embolization coil delivery catheter; stent; covered stent; stent delivery device; aneurysm treatment implant; aneurysm treatment implant delivery device; flow diverter; balloon catheter; and combinations thereof.Imaging probe100 andtreatment device91 have been placed into a vessel, such as a blood vessel of the neck or head.Imaging probe100 andtreatment device91 can be insertable into a single catheter, such asdelivery catheter50dshown.
• Positioning ofoptical assembly130 and resulting images produced assure correct placement of the treatment device91 (e.g. positioning of the stent retriever distal to the thrombus) and also assures that therapy is completed successfully (e.g. sufficient thrombus has been removed), which can both reduce procedure times and improve clinical results.
• In some embodiments,system10 comprises delivery catheter50a(not shown, but such as a 6-8 Fr guide catheter) that can be placed into a target vessel (e.g. artery), such as by using transfemoral access. In some embodiments, delivery catheter50acomprises a standard balloon guide catheter, such as to prevent distal thrombus migration and to enhance aspiration during thrombectomy.System10 can further comprise delivery catheter50b(not shown but such as a flexible 5-6 Fr catheter) that is used as an intermediate catheter, advanced through delivery catheter50ato gain distal access close to the occluded segment of the vessel.System10 can comprise athird delivery catheter50c, shown, such as a 0.021″ to 0.027″ microcatheter used to cross the thrombus or otherwise provide access to a target site to be treated and/or imaged. Angiographic runs can be performed through thedelivery catheter50cto angiographically assess the proper position of thedelivery catheter50ctip (e.g. position of tip distal to the thrombus and to estimate the length of the clot). The treatment device91 (e.g. the stent retriever shown) is subsequently released by pulling backdelivery catheter50cwhile holding thetreatment device91 in place. In some embodiments, thetreatment device91 should cover the entire length of an occlusion in order to achieve flow restoration (e.g. when the stent portion opens).
• InFIG. 8, a distal portion ofdelivery catheter50chas been positioned in a blood vessel (e.g. within a vessel location including thrombus). A stent portion oftreatment device91 remains undeployed, captured within the distal portion ofdelivery catheter50c. InFIG. 9,delivery catheter50cis retracted, such that the stent portion oftreatment device91 deploys (e.g. to engage thrombus, thrombus not shown). InFIG. 10,imaging probe100 is advanced through the deployed stent portion oftreatment device91. Image data can be collected during the advancement. InFIG. 11,imaging probe100 is being retracted (optical assembly130 passes through the stent portion of treatment device91) as image data is collected, such as to perform a procedural assessment as described herein.
• In some embodiments,system10 is constructed and arranged such that proximally applied torque (e.g. to core120) and distally applied rotational speed control (e.g. tocore120 and/or optical assembly130) is provided. This configuration has several benefits, including but not limited to: small size; low-cost; and an independence from the tortuous path proximal to the distal tip ofimaging probe100.
• In some embodiments,system10 is configured to provide precise rotational control (e.g. avoid undesired rotational speed variances ofcore120 and/or optical assembly130) via inertial damping, such as inertial damping which increases with rotational speed. This control can be accomplished with: a viscous fluid in contact withcore120 and/or optical assembly130 (e.g. fluid190aand/or190bdescribed herein); a fluid in contact with a mechanical load such a vane-type micro-structure; a mechanical load acting as a flywheel; and combinations thereof.
• In some embodiments,imaging probe100 comprises a guidewire independent design, comprising ashaft110 with an OD of 0.016″ or less (e.g. approximately 0.014″), and configured such that itsshaft110,core120 andoptical assembly130 are retracted in unison using external pullback (e.g. retraction assembly220 described herein).
• In some embodiments,imaging probe100 is configured to be advanced through vessels to a target site with or without the use of a microcatheter.
• In some embodiments,imaging probe100 is configured such thatcore120 andoptical assembly130 are configured to be retracted withinshaft110 during image data collection, such as an internal pullback using purge media (e.g. fluid190 or other purge media introduced between the core120 and the shaft110). In some embodiments, the introduced material is configured to provide a function selected from the group consisting of: index matching; lubrication; purging of bubbles; and combinations thereof.
• In some embodiments,imaging probe100 comprises an Rx tip. In these embodiments,imaging probe100 can be configured such thatcore120 andoptical assembly130 are configured to be retracted withinshaft110 during image data collection.
• In some embodiments,imaging probe100 comprises a highly deliverable, very small cross-section probe. In some embodiments,shaft110 comprises one or more optically transparent materials providing an optically transparent window,viewing portion117, positioned withindistal portion119aofshaft110.Viewing portion117 can comprise a length between 1 mm and 100 mm, such as a length of approximately 3 mm. In some embodiments,viewing portion117 can comprise a length less than 50 mm, such as less than 20 mm or less than 15 mm (e.g. a relatively short window in embodiments in which bothshaft110 andoptical assembly130 are retracted simultaneously during the collection of image data).Viewing portion117 can comprise a material selected from the group consisting of: nylon; nylon 12; nylon 66; and combinations of one or more of these. In some embodiments, at least a portion ofshaft110 comprises a reinforced portion, such as a reinforced portion comprising a stiffening element (e.g. stiffening element118 shown inFIG. 1). In some embodiments, stiffeningelement118 terminates proximal to optical assembly130 (e.g. proximal toviewing portion117 of shaft110). Alternatively, stiffeningelement118 can extend beyondoptical assembly130, such as is shown inFIG. 2, and the pullback geometry can be coordinated such that the light path to and fromoptical assembly130 avoids thestiffening element118. Stiffeningelement118 can be included to resist twisting ofdistal portion119a, such as during rotation of thecore120. For example, stiffeningelement118 can comprise an element selected from the group consisting of: a coil; a metal coil; a metal coil wound over a plastic such as PTFE; a tube; a metal tube; a metal and/or plastic braid positioned within the wall ofshaft110; and combinations thereof. In some embodiments,shaft110 comprises astiffening element118 comprising a coil wound in a direction such that rotation of thecore120 tends to cause the coil to tighten (e.g. to further resist twisting of shaft110). In some embodiments, one or more portions of stiffeningelement118 come into contact with a fluid maintained within shaft110 (e.g. fluid190 described herein), such that twisting ofshaft110 is reduced by torque forces applied by the fluid to stiffeningelement118.
• In some embodiments,system10 includes integration ofimaging probe100 with one or more therapeutic devices (e.g. one or more treatment devices91). For example, atreatment device91 can comprise a stent retriever, andsystem10 can provide real time simultaneous visualization of one or more of: the patient's anatomy (e.g. blood vessel wall and other tissue of the patient); the treatment device91 (e.g. one or more struts of treatment device91); and/or thrombus or other occlusive matter. The simultaneous visualization can be correlated to reduced procedure time and improved efficacy.
• In some embodiments,system10 is configured to apply proximal pressure toimaging probe100, such as to keep the distal portion bubble-free or at least to mitigate bubble generation within one ormore fluids190 ofimaging probe100.
• As described herein,imaging probe100 can comprise a core120 including a thin fiber that can be optically coupled on its distal end tooptical assembly130 comprising a lens assembly. In some embodiments, a fluid interacting element (e.g. a coil or length of wound wire, though not necessarily a torque wire), can be positioned just proximal to optical assembly130 (e.g. embedded in the wall of or within shaft110). In some embodiments, theshaft110 can be filled with alow viscosity fluid190, such as to interact with the fluid interacting element and create drag. The coil or other fluid interacting element, in contrast to a conventional torque wire, is not wound to create a high-fidelity transmission of torque but to increase viscous drag. The fluid190 can be low viscosity (e.g. with a viscosity at or below 1000 Cp) to allow for easier filling and will reduce bubble artifacts created in high viscosity solutions. The fluid interacting element can comprise an impeller, such asimpeller182 described herein. The fluid interacting element comprises a non-circular cross section portion of a portion ofshaft110, such as a cross section with a geometry selected from the group consisting of: polygon shaped cross section of a lumen ofshaft110; projections into a lumen ofshaft110; recesses in inner diameter (i.e. the inner wall) ofshaft110; and combinations of one or more of these.
• In some embodiments,imaging probe100 comprises a formed element to create viscous drag, such asimpeller182 described herein. This element can have a variety of shapes designed to maximize the interaction with aninternal fluid190.
• In some embodiments,imaging probe100 is constructed and arranged such that viscous drag is created by mechanical friction between a part rigidly coupled tocore120 and in close contact with the wall ofshaft110. The friction may be created by the shear force of a narrow annulus between the mechanical element and theshaft110 wall, such as when theshaft110 is filled withfluid190.
• In some embodiments,imaging probe100 comprises at least onefluid190 that is contained by at least one sealing element (e.g. sealing element116 and/or sealingelement151 described herein).Sealing element116 and/or151 can be constructed and arranged to allowcore120 to rotate in the sealed region while preventing the (viscous) fluid190 to penetrate through the seal. In some embodiments, two sealingelements116aand116bare included, such as one positioned just proximal to theoptical assembly130 and one positioned further distal, such as is shown inFIG. 17. In these embodiments, the separation distance between the two sealingelements116 and/or the viscosity of the capturedfluid190 can be chosen to create sufficient torsional loading ascore120 is rotated. In some embodiments, the two sealingelements116aand116bare positioned apart at a distance between 1 mm and 20 mm. In some embodiments, the fluid190 comprises a viscosity between 10 Cp and 100 Cp.
• In some embodiments,system10 comprises animaging probe100 and aconsole200.Imaging probe100 comprises: aproximal end111 and adistal end119, and at least onelumen112 extending between theproximal end111 and thedistal end119.Core120 is positioned withinlumen112, the proximal end ofcore120 in optical and mechanical communication withconsole200, and the distal end ofcore120 in optical communication with an optical assembly configured to collect image data within a body lumen.
• In some embodiments,imaging probe100 comprisesoptical assembly130 located at the distal end ofcore120,optical assembly130 in mechanical and optical communication withcore120, theoptical assembly130 directing light to the target (e.g. thrombus, vessel wall, tissue and/or implant) being imaged and collecting return light from the imaged target.Imaging probe100 can further comprise an inertial system (e.g. impeller182) located proximate the distal end of thecore120, wherein the inertial system reduces undesired rotational speed variances that occur during a rotation of thecore120. The inertial system can comprise a (predetermined) length of wound hollow core cable, the distal end of the cable being affixed tocore120 just proximal tooptical assembly130, the proximal end unattached (e.g. not attached to core120). The inertial system can comprise a mechanical resistance element located in the distal region ofcore120, and can be in contact with a fluid190 confined within alumen112 ofshaft110, the mechanical resistance arising during rotation within thefluid190.
• In some embodiments,imaging probe100 comprises a sealing element, such as sealingelement151 described herein, located withinlumen112 ofshaft110.Sealing element151 can be configured to allow rotation ofcore120 while forming substantially liquid-tight seals aroundcore120 and the inner wall ofshaft110. In some embodiments, sealingelement151 is further configured as a mechanical resistance element. In some embodiments, sealingelement151 is formed from a hydrogel. In some embodiments, the sealingelement151 is formed by an adhesive (e.g. a UV-cured adhesive), bonding to the inner wall ofshaft110, but not the surface ofcore120. In some embodiments, the surface ofcore120 is configured to avoid bonding to an adhesive (e.g. a UV adhesive). In some embodiments, the sealingelement151 is formed from a compliant material such as a silicone rubber.
• In some embodiments, an imaging system comprises animaging probe100 and an imaging console,console200. Theimaging probe100 comprises: aproximal end111, adistal end119, and at least onelumen112 extending between theproximal end111 anddistal end119. The imaging probe further comprises: a core120 contained within alumen112 of theshaft110, the proximal end ofcore120 in optical and mechanical communication withconsole200, the distal end optically connected to anoptical assembly130 configured to collect image data within a body lumen.Optical assembly130 is positioned at the distal end of thecore120, and is configured to direct light to the target (e.g. thrombus, vessel well, tissue and/or implant) being imaged and collecting return light from the imaged target.
• In some embodiments,imaging probe100 comprises acore120 and one, two or more inertial elements, such asimpeller182 described herein, attached tooptical assembly130 and/or core120 (e.g. attached to a distal portion of core120).Impeller182 can be configured such that when thecore120 is retracted (e.g. in the presence of liquid, gel or gaseous medium, such as fluid190), theimpeller182 imparts a rotational force tocore120, such as to reduce undesired rotational speed variances.Impeller182 can comprise a turbine-like construction.
• In some embodiments,system10 comprises animaging probe100 and an imaging console,console200.Imaging probe100 comprises aproximal end111, adistal end119, and at least onelumen112 extending betweenproximal end111 anddistal end119.Imaging probe100 can further comprise a rotatable optical core,core120 contained within alumen112 ofshaft110, the proximal end ofcore120 in optical and mechanical communication withconsole200, and the distal end configured to collect image data from a body lumen.
• As described herein,imaging probe100 comprisesoptical assembly130 which is positioned at the distal end ofcore120.Optical assembly130 is in mechanical and optical communication withcore120, and is configured to direct light to tissue target being imaged and collect return light from the imaged target.Imaging probe100 can further comprise a reinforcing or other stiffening element (e.g. stiffening element118 described herein) embedded intoshaft110 that creates an improved stiffness but effectively optically transparent window for rotational and pullback scanning. Stiffeningelement118 can comprise an embedded wire and/or a stiffening member (e.g. a plastic stiffening member) inshaft110. Stiffeningelement118 can comprise a spiral geometry. As described hereabove, the spiral geometry of stiffeningelement118 and a pullback spiral rotational pattern ofoptical assembly130 can be matched but offset by approximately one-half of the spiral of stiffeningelement118, such that an imaging beam ofoptical assembly130 passes between the stiffening118 spirals during pullback ofoptical assembly130.
• Referring now toFIG. 12, a side sectional view of the distal portion ofprobe100 is illustrated, having been inserted into a vessel, such thatoptical assembly130 is positioned within treatment device91 (e.g. a stent deployment device, stent retriever or other treatment device), consistent with the present inventive concepts.Probe100 comprisesshaft110,core120,optical assembly130,lens131 andreflector132, and those and other components ofprobe100 can be of similar construction and arrangement to those described hereabove. In some embodiments,distal end119 comprises a geometry and/or a stiffness to enhance advancement ofdistal end119 through blood vessels and/or one or more devices positioned within a blood vessel. For example,distal end119 can comprise the bullet-shaped profile shown inFIG. 12. Alternatively or additionally,treatment device91 can comprise a proximal portion (e.g.proximal end91ashown), which can be configured to enhance delivery ofdistal end119 throughproximal end91a. In some embodiments,probe100 comprises a spring tip, such asspring tip104 described hereabove.
• Probe100 and other components ofsystem10 can be configured to allow a clinician or other operator to “view” (e.g. in real time) the collection of thrombus or other occlusive matter intotreatment device91, such as to determine when to removetreatment device91 and/or how to manipulate treatment device91 (e.g. a manipulation to removetreatment device91 and/or repositiontreatment device91 to enhance the treatment). The ability to view the treatment can avoid unnecessary wait time and other delays, as well as improve efficacy of the procedure (e.g. enhance removal of thrombus).
• Referring now toFIG. 13, a side sectional view of the distal portion ofprobe100 is illustrated, consistent with the present inventive concepts.Probe100 comprisesshaft110,lumen112,core120,optical assembly130,lens131 andreflector132, and those and other components ofprobe100 can be of similar construction and arrangement to those described hereabove. In some embodiments,distal portion119aofshaft110 comprises a reinforcing element, stiffeningelement118aas shown inFIG. 13. Inclusion of stiffeningelement118acan allow the wall ofshaft110 surroundingoptical assembly130 to be thin (e.g. thinner than the wall in a more proximal portion of shaft110). Stiffeningelement118acan comprise an optically transparent material as described herein. Stiffeningelement118acan be configured to provide column and/or torsional strength toshaft110. In some embodiments,probe100 comprises a lumen narrowing structure, such astube114 shown positioned withinlumen112 ofshaft110.Tube114 can be adhesively or at least frictionally engaged with the inner wall ofshaft110 or the outer surface ofcore120. In some embodiments,tube114 is simply a projection from the inner wall of shaft110 (e.g. part of shaft110).Tube114 can be configured to provide a function selected from the group consisting of: increase torsional strength ofshaft110; increase column strength ofshaft110; provide a capillary action betweenfluid surrounding core120 and/oroptical assembly130; and combinations thereof. In some embodiments,probe100 comprises fluid190aand/orfluid190bshown, such as is described hereabove. Fluid190aandfluid190bcan comprise similar or dissimilar fluids. In some embodiments, fluid190aand/orfluid190bcomprise a low viscosity fluid as described hereabove. In some embodiments, fluid190aand/orfluid190bcomprise a shear-thinning fluid as described hereabove.
• Referring now toFIG. 14, a schematic of an imaging probe is illustrated, shown in a partially assembled state and consistent with the present inventive concepts. Probe100 can comprise a first portion, comprising aconnector102a,outer shaft110aandspring tip104, constructed and arranged as shown inFIG. 14. Probe100 can further comprise a second portion,connector102b,torque shaft110b,core120 andoptical assembly130.Outer shaft110a,spring tip104,core120 andoptical assembly130 and other components ofprobe100 can be of similar construction and arrangement to those described hereabove.Connector102bcan be of similar construction and arrangement toconnector102 described hereabove, such as to optically connectprobe100 toconsole200.Connector102acan be configured to surround and mechanically engageconnector102b, such thatconnectors102aand/or102bmechanically connect to console200.
• Torque shaft110bfrictionally engages core120 (e.g. via an adhesive), at least at a distal portion oftorque shaft110b.Torque shaft110bcan be attached toconnector102bvia an adhesive or other mechanical engagement (e.g. via a metal tube, not shown, but such as a tube that is pressed intoconnector102b). In some embodiments, a strain relief is provided at the end oftorque shaft110b,tube121 shown.Tube121 can be configured to reduce kinking and/or to increase the fixation betweentorque shaft110bandcore120.Tube121 andtorque shaft110bcan have similar IDs and/or ODs.
• During assembly,torque shaft110b,optical assembly130 andcore120 are positioned withinshaft110a.Connector102acan be engaged withconnector102bto maintain relative positions of the two components.
• Torque shaft110bcan comprise one or more plastic or metal materials, such as whentorque shaft110bcomprises a braided torque shaft (e.g. a braid comprising at least stainless steel).Torque shaft110bcan comprise a length such that the distal end oftorque shaft110bterminates a minimum distance away fromoptical assembly130, such as a length of approximately 49 cm. In some embodiments,torque shaft110bcomprises a length such that none or a small portion oftorque shaft110benters the patient. In these embodiments,retraction assembly220 can be positioned and engageshaft110 at a location distal to the distal end ofretraction assembly220.
• Referring now toFIGS. 15A-C, a series of side sectional views of an imaging probe in a series of expansion steps of its shaft via an internal fluid, consistent with the present inventive concepts.Probe100 comprisesconnector102,shaft110,core120 andoptical assembly130, and those and other components ofprobe100 can be of similar construction and arrangement to those described hereabove.Shaft110 comprisesproximal portion111a,mid portion115 anddistal portion119a. Probe100 further comprisespressurization assembly183, which may includevalve184, each of which can be of similar construction and arrangement to the similar components described hereabove in reference toFIG. 7. Probe100 can be configured such that as fluid is introduced intolumen112, and/or the pressure of fluid withinlumen112 is increased,shaft110 expands. For example, a first introduction offluid190 intolumen112 and/or a first increase of pressure offluid190 in lumen112 (e.g. via pressurization assembly183) can be performed such that theproximal portion111aofshaft110 expands as shown inFIG. 15A. Subsequently, a second introduction offluid190 intolumen112 and/or a second increase of pressure offluid190 inlumen112 can be performed such that themid portion115 ofshaft110 expands as shown inFIG. 15B. Subsequently, a third introduction offluid190 intolumen112 and/or a third increase of pressure offluid190 inlumen112 can be performed such that thedistal portion119aofshaft110 expands as shown inFIG. 15C. In some embodiments,shaft110 is expanded to create a space between the inner wall ofshaft110 andcore120 and/or to create a space between the inner wall ofshaft110 andoptical assembly130.
• Referring now toFIG. 16, a side sectional view of the distal portion of an imaging probe comprising a distal marker positioned in reference to an optical assembly is illustrated, consistent with the present inventive concepts.Probe100 comprisesshaft110,core120,optical assembly130,lens131 andreflector132, and those and other components ofprobe100 can be of similar construction and arrangement to those described hereabove.Shaft110 comprisesproximal portion111a(not shown),distal portion119aanddistal end119. Probe100 can comprise afunctional element133a, which can be positioned on or relative to optical assembly130 (e.g. positioned on or at a desired and/or known distance from optical assembly130).Functional element133ais shown positioned distal tooptical assembly130, and at a fixed distance as determined by a connecting element, tube134 (e.g. heat shrink tubing or other plastic tube). In some embodiments,functional element133acomprises a sensor, transducer or other functional element as described herein. In some embodiments,functional element133acomprises a visualizable element, such as a radiopaque element, ultrasonically visible element and/or magnetically visible element. In some embodiments,functional element133acomprises a visualizable element used to identify the location ofoptical assembly130 on an image produced by an imaging device (e.g. a fluoroscope, ultrasonic imager or MRI) and the fixed location offunctional element133arelative tooptical assembly130 avoids registration issues, such as would be encountered iffunctional element133awas positioned onshaft110 or other component ofprobe100 whose dimensions or other relative position tooptical assembly130 may change over time (e.g. due to expansion or contraction due to temperature shifts). In some embodiments,functional element133ais attached tooptical assembly130 via a connecting element, such astube134 described hereabove, andtube134 or other connecting element (e.g. connecting element137 described herein) is configured to avoid dimensional changes (e.g. is minimally affected by changes in temperature). In some embodiments,probe100 comprises fixation element136 (e.g. an adhesive such as a UV cured adhesive) positioned just distal tofunctional element133aas shown inFIG. 16, and configured to maintain the position offunctional element133a.
• Probe100 can comprise one or more elements that cause frictional engagement betweenshaft110 andcore120 and/or simply reduce the space betweenshaft110 andcore120, such as one or more ofelements122a,122band122cshown inFIG. 16, such as to reduce undesired variations in rotational rate as described herein. In some embodiments,probe100 comprises a compression element,band122a, positioned about and/or withinshaft110 and causing a portion of the inner wall ofshaft110 to frictionally engagecore120. Alternatively or additionally,shaft110 can comprise one ormore projections122b(e.g. annular projections) that extend to frictionally engagecore120. Alternatively or additionally,core120 can comprise one ormore projections122c, each extending to frictionally engageshaft110. One or more of each ofelements122a,122band/or122ccan be included, and each can be configured to create a shear force that applies a load tocore120 during rotation ofcore120. In some embodiments, a fluid190 is positioned betweenshaft110 andcore120, such as a shear-thinning fluid as described herein. In these embodiments, one or more ofelements122a,122band/or122ccan comprise a space reducing element configured to increase the shear-thinning of the fluid190 ascore120 is rotated (i.e. by interacting with the fluid190 to increase the amount of thinning than that which would have occurred without the presence of the one or more space reducing elements122).
• Referring now toFIG. 17, a side sectional view of the distal portion of an imaging probe comprising two sealing elements is illustrated, consistent with the present inventive concepts.Probe100 comprisesshaft110,core120,optical assembly130,lens131,reflector132 andviewing portion117, and those and other components ofprobe100 can be of similar construction and arrangement to those described hereabove.Shaft110 compriseslumen112,proximal portion111a(not shown),distal portion119aanddistal end119. Probe100 can further comprisespring tip104. Probe100 can comprisefunctional element113, as shown, or other functional elements as described herein. Probe100 ofFIG. 17 comprises two sealing elements, sealingelement116a(e.g. an O-ring surrounding core120) and sealingelement116b(e.g. an elastomeric disk). In some embodiments, a fluid190bis positioned withinshaft110 between sealingelements116aand116b, such as is described hereabove. Alternatively or additionally, asecond fluid190ais positioned withinshaft110 proximal to sealingelement116a. In some embodiment, a third fluid190c(not shown), is positioned withinshaft110 distal to sealingelement116b.Fluids190a-ccan comprise similar or dissimilar fluids, also as described hereabove.
• Referring now toFIG. 18, a side sectional view of the distal portion of an imaging probe comprising a reflecting element offset from a lens and multiple visualizable markers is illustrated, consistent with the present inventive concepts.Probe100 comprisesshaft110,core120,optical assembly130,lens131 andreflector132, and those and other components ofprobe100 can be of similar construction and arrangement to those described hereabove.Shaft110 compriseslumen112,proximal portion111a(not shown),distal portion119aanddistal end119.
• In some embodiments,reflector132 can be positioned distal tolens131, and connected via connectingelement137, as shown inFIG. 18 and described hereabove.
• In some embodiments,probe100 comprises multiple visualizable markers, such as the fourfunctional elements123ashown inFIG. 18, which can be configured to provide a “ruler function” when visualized by a separate imaging device such as a fluoroscope, ultrasonic imager or MRI (e.g. whenfunctional elements123acomprise a radiopaque marker; an ultrasonically reflective marker or a magnetic marker, respectively).Functional elements123acan comprise one or more visualizable bands (e.g. one or more compressible bands and/or wire coils) frictionally engaged withcore120. Alternatively or additionally, one or morefunctional elements123acan be positioned on, within the wall of and/or on the inner surface ofshaft110.Functional elements123acan be positioned equidistantly apart and/or at a known separation distance. In some embodiments, one or morefunctional elements123acan be further configured as a sealing element (e.g. to provide a seal to a contained fluid such as one ormore fluids190 described herein) and/or as a rotational dampener configured to reduce undesired rotational velocity changes ofcore120 and/oroptical assembly130.
• While the preferred embodiments of the devices and methods have been described in reference to the environment in which they were developed, they are merely illustrative of the principles of the present inventive concepts. Modification or combinations of the above-described assemblies, other embodiments, configurations, and methods for carrying out the inventive concepts, and variations of aspects of the inventive concepts that are obvious to those of skill in the art are intended to be within the scope of the claims. In addition, where this application has listed the steps of a method or procedure in a specific order, it may be possible, or even expedient in certain circumstances, to change the order in which some steps are performed, and it is intended that the particular steps of the method or procedure claim set forth herebelow not be construed as being order-specific unless such order specificity is expressly stated in the claim.

Claims (18)

1. (canceled)

2. An imaging system for a patient comprising:

an imaging probe comprising:

an elongate shaft for insertion into the patient and comprising a proximal end, a distal portion, and a lumen extending between the proximal end and the distal portion;

a rotatable optical core comprising a proximal end and a distal end, the rotatable optical core configured to optically and mechanically connect with a console;

a probe connector positioned on the elongate shaft proximal end and surrounding at least a portion of the rotatable optical core; and

an optical assembly positioned in the elongate shaft distal portion and proximate the rotatable optical core distal end, the optical assembly configured to direct light to tissue and collect reflected light from the tissue;

wherein the imaging probe is constructed and arranged to collect image data from a patient site based on the directed light and the reflected light,

wherein the optical assembly is configured to be positioned within a first blood vessel proximate a patient site and to collect the image data from the patient site, and

wherein the patient site comprises a location outside of the blood vessel.

3. The imaging system according toclaim 2, wherein the patient site comprises a location within the intrathecal space of the spine.

4. The imaging system according toclaim 2, wherein the patient site comprises a location within a second blood vessel that is outside of the first blood vessel.

5. The imaging system according toclaim 2, wherein the patient site comprises a location within tissue that is outside of the first blood vessel.

6. The imaging system according toclaim 2, wherein the imaging probe is configured to access blood vessels of the brain.

7. The imaging system according toclaim 2, wherein the optical assembly comprises an outer diameter that is greater than an inner diameter of at least a portion of the elongate shaft proximal to the optical assembly.

8. The imaging system according toclaim 2, wherein the imaging system includes a sensor that receives a signal related to the tissue, the console configured to process the signal, and a display configured to display a three-dimensional image from an output of the console in response to a retraction of the elongate shaft.

9. The imaging system according toclaim 2, wherein the elongate shaft distal portion comprises an optically transparent window, and wherein the optical assembly is positioned within the optically transparent window.

10. The imaging system according toclaim 9, wherein the optically transparent window comprises a length less than 20 mm.

11. The imaging system according toclaim 2, wherein the rotatable optical core is constructed and arranged to rotate in a single direction.

12. The imaging system according toclaim 2, further comprising a retraction assembly constructed and arranged to retract the elongate shaft and the optical assembly while the imaging probe collects data from a target area.

13. The imaging system according toclaim 2, wherein the imaging probe of the imaging system is configured to provide to the console quantitative or qualitative information used to determine the size of a flow diverter of an implant to be implanted in the patient or position a flow diverter in the patient.

14. The imaging system according toclaim 13, wherein the quantitative and/or qualitative information comprises information related to a parameter selected from the group consisting of: perforator location; perforator geometry; neck size; flow diverter mesh density; and combinations thereof.

15. The imaging system according toclaim 2, wherein the imaging probe of the imaging system is configured to provide implant site information, and wherein the implant site information is used to select a particular implantable device for implantation in the patient.

16. The imaging system according toclaim 2, wherein the imaging probe further comprises a torque shaft with a proximal end and a distal end, and wherein the torque shaft is fixedly attached to the rotatable optical core such that rotation of the torque shaft rotates the rotatable optical core.

17. The imaging system according toclaim 2, further comprising a rotation assembly constructed and arranged to rotate the rotatable optical core.

18. The imaging system according toclaim 2, wherein the console comprises:

a rotation assembly constructed and arranged to rotate the rotatable optical core; and

a retraction assembly constructed and arranged to retract at least one of the rotatable optical core or the elongate shaft.

Images