US20210353359A1 - Active alignment system and method for optimizing optical coupling of multiplexer for laser-driven intravascular lithotripsy device - Google Patents

Abstract

A catheter system (100) for treating a treatment site (106) within or adjacent to a vessel wall (108) or heart valve includes a first light source (124), a plurality of light guides (122A), a multiplexer (128) and a multiplexer alignment system (142). The first light source (124) generates light energy. The plurality of light guides (122A) are each configured to alternatingly receive light energy from the first light source (124). Each light guide (122A) has a guide proximal end (122P). The multiplexer (128) receives the light energy from the first light source (124). The multiplexer (128) alternatingly directs the light energy from the first light source (124) to each of the plurality of light guides (122A). The multiplexer alignment system (142) is operatively coupled to the multiplexer (128). The multiplexer alignment system (142) includes a second light source (270) that generates a probe source beam (270A) that scans the guide proximal end (122P) of each of the plurality of light guides (122A).

Description

RELATED APPLICATION
• This application claims priority from U.S. Provisional Application Ser. No. 63/023,669, filed on May 12, 2020. To the extent permitted, the contents of U.S. Provisional Application Ser. No. 63/023,669 are incorporated in their entirety herein by reference.
BACKGROUND
• Vascular lesions within vessels in the body can be associated with an increased risk for major adverse events, such as myocardial infarction, embolism, deep vein thrombosis, stroke, and the like. Severe vascular lesions can be difficult to treat and achieve patency for a physician in a clinical setting.
• Vascular lesions may be treated using interventions such as drug therapy, balloon angioplasty, atherectomy, stent placement, vascular graft bypass, to name a few. Such interventions may not always be ideal or may require subsequent treatment to address the lesion.
SUMMARY
• The present invention is directed toward a catheter system for treating a treatment site within or adjacent to a vessel wall or heart valve. In various embodiments, the catheter system includes a first light source, a plurality of light guides, a multiplexer and a multiplexer alignment system. The first light source generates light energy. The plurality of light guides are each configured to alternatingly receive light energy from the first light source. Each light guide has a guide proximal end. The multiplexer receives the light energy from the first light source. The multiplexer alternatingly directs the light energy from the first light source to each of the plurality of light guides. The multiplexer alignment system is operatively coupled to the multiplexer. The multiplexer alignment system includes a second light source that generates a probe source beam that scans the guide proximal end of each of the plurality of light guides.
• In some embodiments, the probe source beam scanning the guide proximal end of each of the plurality of light guides produces a backscattered energy beam that is scattered off of the guide proximal end of each of the plurality of light guides. In such embodiments, the catheter system can further include a system controller including a processor that analyzes the backscattered energy beam to determine optimal optical coupling between the guide beams and the plurality of light guides.
• In certain embodiments, the first light source provides the light energy in the form of a source beam that is directed toward the multiplexer. In such embodiments, the system controller is configured to control operation of the first light source to generate a single source beam in the form of pulses of light energy.
• In some embodiments, the plurality of light guides are retained at least partially within a guide coupling housing; and wherein the probe source beam is configured to scan a face of the guide coupling housing. In such embodiments, the guide proximal end of each of the plurality of light guides can be retained within the guide coupling housing.
• In certain embodiments, the multiplexer alignment system is operatively coupled to the multiplexer such that the probe source beam scans the guide proximal end of each of the plurality of light guides a predetermined time prior to the individual guide beams scanning the guide proximal end of each of the plurality of light guides.
• In some embodiments, the catheter system further includes a system console that includes the multiplexer and the multiplexer alignment system, and the plurality of light guides are mechanically coupled to the system console.
• In certain embodiments, the multiplexer alignment system includes coupling optics that are configured to focus the probe source beam to scan the guide proximal end of each of the plurality of light guides. In some embodiments, the multiplexer can utilize the coupling optics to focus each of the individual guide beams to one of the plurality of light guides. Alternatively, the multiplexer utilizes alternative coupling optics to focus each of the individual guide beams to one of the plurality of light guides.
• In various embodiments, the catheter system further includes a first beamsplitter that receives a source beam from the first light source and the probe source beam from the second light source, the first beamsplitter being configured to direct each of the source beam and the probe source beam toward the guide proximal end of each of the plurality of light guides. In one such embodiment, the first beamsplitter is a dichroic beamsplitter. In certain embodiments, the first beamsplitter is configured to transmit one of the source beam and the probe source beam and to reflect the other of the source beam and the probe source beam.
• The catheter system can further include a second beamsplitter and a photodetector. In such embodiments, the second beamsplitter is configured to receive the backscattered energy beam and direct at least a portion of the backscattered energy beam toward the photodetector. In one such embodiment, the second beamsplitter is a 10/90 beamsplitter that redirects approximately 90 percent of the backscattered energy beam toward the photodetector. Alternatively, the second beamsplitter can have another suitable design that transmits more or less than ten percent of the backscattered energy beam, and redirects more or less than 90 percent of the backscattered energy beam. Further, in such embodiments, the photodetector can generate a signal based at least in part on the at least a portion of the backscattered energy beam that is directed toward the photodetector. Still further, the signal from the photodetector can be amplified with an amplifier to provide an amplified signal. In such embodiments, the amplified signal is directed to signal processing electronics to determine an intensity of light energy contained within the backscattered energy beam. Moreover, in such embodiments, the intensity of light energy contained within the backscattered energy beam is evaluated to determine optimal optical coupling between the guide beams and the plurality of light guides.
• In some embodiments, the catheter system further includes a power source that is configured to provide power to each of the first light source, the system controller, the multiplexer and the multiplexer alignment system.
• In certain embodiments, the multiplexer alignment system includes coupling optics that are configured to focus the probe source beam to scan the guide proximal end of each of the plurality of light guides. In one such embodiment, the coupling optics are positioned in the beam path of the probe source beam between the first beamsplitter and the plurality of light guides. In another such embodiment, the coupling optics are positioned in the beam path of the probe source beam between the first beamsplitter and the second beamsplitter.
• In certain embodiments, the multiplexer includes a multiplexer base, a multiplexer stage, and a stage mover that moves the multiplexer stage in a single linear degree of freedom relative to the multiplexer base. In some embodiments, the first beamsplitter, the second beamsplitter, and the coupling optics can be mounted on the multiplexer stage. In some such embodiments, the multiplexer further includes a redirector that is mounted on the multiplexer stage, the redirector being configured to direct a source beam from the first light source toward the coupling optics. In such embodiments, movement of the multiplexer stage relative the multiplexer base moves the source beam and the probe source beam relative to the plurality of light guides so that the individual guide beams and the probe source beam are directed to scan across the guide proximal end of each of the plurality of light guides.
• In various embodiments, the multiplexer includes a first movable redirector and a second movable redirector that are positioned in an optical path of a source beam from the first light source and in an optical path of the probe source beam from the second light source. In such embodiments, the first movable redirector is movable about an axis with a first redirector mover; the second movable redirector is movable about an axis with a second redirector mover, and movement of the first movable redirector and the second movable redirector cooperate to direct the source beam as individual guide beams, and the probe source beam toward coupling optics so that the guide beams and the probe source beam scan across the guide proximal end of each of the plurality of light guides. In certain embodiments, at least one of the first movable redirector and the second movable redirector includes a galvanometer mirror scanner.
• In certain embodiments, the multiplexer includes a multiplexer stage and a stage mover that moves the multiplexer stage relative to each of the plurality of light guides. In such embodiments, the stage mover can move the multiplexer stage rotationally about a rotational axis. Further, in some such embodiments, the light energy from the first light source is directed toward the multiplexer stage as a single source beam substantially along the rotational axis. Moreover, in certain such embodiments, the multiplexer further includes a beam path adjuster; the source beam and the probe source beam are directed substantially along the rotational axis toward the beam path adjuster, and the beam path adjuster is configured to redirect the source beam and the probe source beam such that the source beam and the probe source beam are directed in a direction that is parallel to and spaced apart from the rotational axis. In alternative embodiments, the beam path adjuster includes one of an anamorphic prism pair, a pair of wedge prisms, a pair of close-spaced right-angle mirrors, and a pair of close-spaced right-angle prisms. In some embodiments, the beam path adjuster is movable to direct the source beam as individual guide beams, and the probe source beam toward coupling optics so that the guide beams and the probe source beam scan rotationally across the guide proximal end of each of the plurality of light guides.
• In various embodiments, the first light source includes a laser. In some such embodiments, the first light source includes a pulsed infrared light source.
• In various embodiments, the second light source includes a laser. In certain such embodiments, the second light source includes a visible light, continuous wave light source.
• The present invention is further directed toward a method for treating a treatment site within or adjacent to a vessel wall or heart valve, the method including any of the catheter systems described above.
• In certain embodiments, the multiplexer can include a first movable redirector and a second movable redirector. In various embodiments, at least one of the redirectors includes a multi-directional scanner with an f-theta lens.
• The present invention is further directed toward a method for treating a treatment site within or adjacent to a vessel wall or heart valve, the method comprising the steps of generating light energy with a first light source; receiving the light energy from the first light source with a multiplexer; directing the light energy from the first light source with the multiplexer in the form of individual guide beams to each of a plurality of light guides; operatively coupling a multiplexer alignment system to the multiplexer; and generating a probe source beam with a second light source so that the multiplexer alignment system scans a guide proximal end of each of the plurality of light guides.
• This summary is an overview of some of the teachings of the present application and is not intended to be an exclusive or exhaustive treatment of the present subject matter. Further details are found in the detailed description and appended claims. Other aspects will be apparent to persons skilled in the art upon reading and understanding the following detailed description and viewing the drawings that form a part thereof, each of which is not to be taken in a limiting sense. The scope herein is defined by the appended claims and their legal equivalents.
BRIEF DESCRIPTION OF THE DRAWINGS
• The novel features of this invention, as well as the invention itself, both as to its structure and its operation, will be best understood from the accompanying drawings, taken in conjunction with the accompanying description, in which similar reference characters refer to similar parts, and in which:
• FIG. 1 is a schematic cross-sectional view of an embodiment of a catheter system in accordance with various embodiments herein, the catheter system including a first light source, a plurality of light guides, a multiplexer, and a multiplexer alignment system;
• FIG. 2 is a simplified schematic illustration of a portion of an embodiment of the catheter system including an embodiment of the multiplexer and the multiplexer alignment system;
• FIGS. 3A-3D are a schematic illustration representative of a timing scheme as the multiplexer and the multiplexer alignment system are scanning relative to the plurality of light guides, and a graphical representation of backscattered beam intensity as a function of scan position which is used to determine proper timing for firing of the first light source;
• FIG. 4 is a simplified schematic illustration of a portion of another embodiment of the catheter system including another embodiment of the multiplexer and the multiplexer alignment system;
• FIG. 5 is a simplified schematic illustration of a portion of still another embodiment of the catheter system including still another embodiment of the multiplexer and the multiplexer alignment system;
• FIG. 6 is a simplified schematic illustration of a portion of yet another embodiment of the catheter system including yet another embodiment of the multiplexer and the multiplexer alignment system; and
• FIG. 7 is a simplified schematic illustration of a portion of still yet another embodiment of the catheter system including still yet another embodiment of the multiplexer and the multiplexer alignment system.
• While embodiments of the present invention are susceptible to various modifications and alternative forms, specifics thereof have been shown by way of example and drawings, and are described in detail herein. It is understood, however, that the scope herein is not limited to the particular embodiments described. On the contrary, the intention is to cover modifications, equivalents, and alternatives falling within the spirit and scope herein.
DESCRIPTION
• Treatment of vascular lesions can reduce major adverse events or death in affected subjects. As referred to herein, a major adverse event is one that can occur anywhere within the body due to the presence of a vascular lesion. Major adverse events can include, but are not limited to, major adverse cardiac events, major adverse events in the peripheral or central vasculature, major adverse events in the brain, major adverse events in the musculature, or major adverse events in any of the internal organs.
• For the treatment of vascular lesions, such as calcium deposits in arteries, it is generally beneficial to be able to treat multiple closely spaced areas with a single insertion and positioning of a catheter balloon. To allow this to occur within an optical excitation system, such as within a laser-driven intravascular lithotripsy device, it is usually desirable to have a number of output channels, e.g., optical fibers and targets, for the treatment process, each output channel including an emitter, e.g., a plasma generator, which can be distributed at appropriate and desired locations within the balloon. Since a high-power laser source is often the largest and most expensive component in the system, having a dedicated laser source for each optical fiber is unlikely to be feasible for a number of reasons including packaging requirements, power consumption, thermal considerations, and economics. For such reasons, it can be advantageous to multiplex a single laser simultaneously and/or sequentially into a number of different optical fibers for treatment purposes. This allows the possibility for using all or a particular portion of the laser power from the single laser with each fiber.
• Thus, the catheter systems and related methods disclosed herein are configured to provide a means to power multiple fiber optic channels in a laser-driven pressure wave-generating device that is designed to impart pressure onto and induce fractures in vascular lesions, such as calcified vascular lesions and/or fibrous vascular lesions, using a single light source. More particularly, the invention described in detail herein includes a multiplexer that multiplexes a single energy source or light source, e.g., a single laser source, into one or more of multiple light guides, e.g., fiber optic channels, in a single-use device.
• As described in detail herein, the catheter systems and methods of the present invention further incorporate a means to improve optical coupling to an individual output channel, e.g., optical fiber, which is organized in a multi-channel array. The active optical system measures coupling efficiency continuously during the action of the multiplexer and determines the optimal parameters to trigger the energy source. For example, in various embodiments, the present invention incorporates a second energy source to probe the face of the multi-channel array and the individual optical fibers within the multi-channel array. The source is coupled to a common path with the beam of the primary energy source. The focused probe beam spot can be coincident with the primary energy spot or offset to provide scan ahead timing giving the system predictable control over firing of the primary energy source, e.g., the laser. The focused probe beam spot scatters off the face of the multi-channel array and the individual optical fibers. Optics and sensors allow continuous monitoring of the light returned from the probe beam spot. The relative intensity of the returned light correlates and a corresponding signal produced by signal processing electronics correlate to coupling efficiency. As such, the scanning process generates a data stream from which coupling efficiency as a function of multiplexer position is determined. In certain embodiments, the projected spot from the primary energy source laser is configured to lag that of the probe spot in a tightly controlled or calibrated manner. Thus, the system controls parametric motion of the multiplexer and computes optimal time to fire the primary energy source once the multiplexer is in the optimal location. In other embodiments, the probe beam spot can be utilized within an active scanning system that goes through every fiber and finds the X-Y location for each fiber that gives optimal coupling, and doing this without firing the main energy source. Thus, the second energy source could go slowly and do a thorough X-Y scan across the face of the multi-channel array and map the whole thing out. The system would then store that information and use those locations for real-time firing of the primary energy source.
• With such designs, the systems and methods of the present invention can be implemented for any multiplexer configuration, either linear, circular, patterned or scanned, provided that the probe and primary laser beams can be combined and spot traced by beam paths, which can then be correlated to parametric motion of the multiplexer mechanism.
• It is appreciated that the catheter system and methods of the present invention provide various advantages and/or solves key problems including one or more of: 1) reducing system optical coupling dependence on mechanical tolerances of the output channels (optical fibers) and tolerances of their location in a multi-channel array, 2) reducing performance dependence on the accuracy of connecting and aligning the multi-channel array to the multiplexer, 3) reducing dependence on the accuracy of the positioning mechanism in the multiplexer and the associated quality and precision of its optical and mechanical components, 4) improving speed and performance of the multiplexer and the multi-channel array system, and 5) making it possible to use low cost, low accuracy multi-channel arrays on the single-use device, thereby improving cost targets.
• In various embodiments, the catheter systems disclosed herein can include a catheter configured to advance to the treatment site within or adjacent a blood vessel or heart valve within the body of a patient. The catheter includes a catheter shaft, and a balloon that is coupled and/or secured to the catheter shaft. The balloons herein can include a balloon wall that defines a balloon interior and can be configured to receive a balloon fluid within the balloon interior to expand from a deflated configuration suitable for advancing the catheter through a patient's vasculature, to an inflated configuration suitable for anchoring the catheter in position relative to the treatment site. The catheter systems also include the plurality of light guides disposed along the catheter shaft and within the balloon. Each light guide can be configured for generating pressure waves within the balloon for disrupting the vascular lesions.
• In various embodiments, the catheter systems and related methods of the present invention utilize a high energy source, e.g., a light source such as a high energy laser source or another suitable high energy source, which provides energy that is guided by an energy guide, e.g., a light guide, to create a localized plasma in the balloon fluid that is retained within a balloon interior of an inflatable balloon of the catheter. As such, the energy guide can sometimes be referred to as, or can be said to incorporate a “plasma generator” at or near a guide distal end of the energy guide that is positioned within the balloon interior. The creation of the localized plasma, in turn, induces a high energy bubble inside the balloon interior to create pressure waves to impart pressure onto and induce fractures in a treatment site, such as a calcified vascular lesion or a fibrous vascular lesion, at a treatment site within or adjacent to a blood vessel wall within a body of a patient.
• In some embodiments, the energy source can be configured to provide sub-millisecond pulses of energy, e.g., light energy, from the energy source to initiate plasma formation in the balloon fluid within the balloon to cause rapid bubble formation and to impart pressure waves upon the balloon wall at the treatment site. Thus, the pressure waves can transfer mechanical energy through an incompressible balloon fluid to the treatment site to impart a fracture force on the treatment site. As used herein, the treatment site can include a vascular lesion such as a calcified vascular lesion or a fibrous vascular lesion, typically found in a blood vessel and/or a heart valve.
• As used herein, the terms “intravascular lesion”, “vascular lesion” and “treatment site” are used interchangeably unless otherwise noted. As such, the intravascular lesions and/or the vascular lesions are sometimes referred to herein simply as “lesions”.
• Those of ordinary skill in the art will realize that the following detailed description of the present invention is illustrative only and is not intended to be in any way limiting. Other embodiments of the present invention will readily suggest themselves to such skilled persons having the benefit of this disclosure. Reference will now be made in detail to implementations of the present invention as illustrated in the accompanying drawings.
• In the interest of clarity, not all of the routine features of the implementations described herein are shown and described. It will, of course, be appreciated that in the development of any such actual implementation, numerous implementation-specific decisions must be made in order to achieve the developer's specific goals, such as compliance with application-related and business-related constraints, and that these specific goals will vary from one implementation to another and from one developer to another. Moreover, it is appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking of engineering for those of ordinary skill in the art having the benefit of this disclosure.
• It is appreciated that the catheter systems disclosed herein can include many different forms. Referring now toFIG. 1, a schematic cross-sectional view is shown of acatheter system100 in accordance with various embodiments herein. As described herein, thecatheter system100 is suitable for imparting pressure to induce fractures in one or more treatment sites within or adjacent a vessel wall of a blood vessel or heart valve within a body of a patient. In the embodiment illustrated inFIG. 1, thecatheter system100 can include one or more of acatheter102, alight guide bundle122 including one or more (and preferably a plurality of) light guides122A, asource manifold136, afluid pump138, and asystem console123 including one or more of a light source124 (sometimes referred to herein as a “first light source”), apower source125, asystem controller126, a graphic user interface127 (a “GUI”), amultiplexer128, and amultiplexer alignment system142. Alternatively, thecatheter system100 can include more components or fewer components than those specifically illustrated inFIG. 1.
• Thecatheter102 is configured to move to atreatment site106 within or adjacent to ablood vessel108 within abody107 of apatient109. Thetreatment site106 can include one or more vascular lesions such as calcified vascular lesions, for example. Additionally, or in the alternative, thetreatment site106 can include vascular lesions such as fibrous vascular lesions.
• Thecatheter102 can include an inflatable balloon104 (sometimes referred to herein simply as a “balloon”), acatheter shaft110 and aguidewire112. Theballoon104 can be coupled to thecatheter shaft110. Theballoon104 can include a balloonproximal end104P and a balloondistal end104D. Thecatheter shaft110 can extend from aproximal portion114 of thecatheter system100 to adistal portion116 of thecatheter system100. Thecatheter shaft110 can include alongitudinal axis144. Thecatheter shaft110 can also include aguidewire lumen118 which is configured to move over theguidewire112. Thecatheter shaft110 can further include an inflation lumen (not shown). In some embodiments, thecatheter102 can have adistal end opening120 and can accommodate and be tracked over theguidewire112 as thecatheter102 is moved and positioned at or near thetreatment site106. In some embodiments, the balloonproximal end104P can be coupled to thecatheter shaft110, and the balloondistal end104D can be coupled to theguidewire lumen118.
• Thecatheter shaft110 of thecatheter102 can be coupled to the one or more light guides122A of thelight guide bundle122 that are in optical communication with thelight source124. The light guide(s)122A can be disposed along thecatheter shaft110 and within theballoon104. Additionally, each of the light guides122A can have a guidedistal end122D that is at any suitable longitudinal position relative to a length of theballoon104. In some embodiments, eachlight guide122A can be an optical fiber and thelight source124 can be a laser. Thelight source124 can be in optical communication with the light guides122A at theproximal portion114 of thecatheter system100. More particularly, as described in detail herein, thelight source124 can selectively and/or alternatively be in optical communication with each of the light guides122A in any desired combination, order and/or pattern due to the presence and operation of themultiplexer128. Additionally, as described herein, thelight source124 can be more precisely and accurately coupled in optical communication with each of the light guides122A due to the presence of themultiplexer alignment system142.
• In some embodiments, thecatheter shaft110 can be coupled to multiplelight guides122A such as a first light guide, a second light guide, a third light guide, etc., which can be disposed at any suitable positions about theguidewire lumen118 and/or thecatheter shaft110. For example, in certain non-exclusive embodiments, twolight guides122A can be spaced apart by approximately 180 degrees about the circumference of theguidewire lumen118 and/or thecatheter shaft110; threelight guides122A can be spaced apart by approximately 120 degrees about the circumference of theguidewire lumen118 and/or thecatheter shaft110; or fourlight guides122A can be spaced apart by approximately 90 degrees about the circumference of theguidewire lumen118 and/or thecatheter shaft110. Still alternatively, multiplelight guides122A need not be uniformly spaced apart from one another about the circumference of theguidewire lumen118 and/or thecatheter shaft110. More particularly, it is further appreciated that the light guides122A described herein can be disposed uniformly or non-uniformly about theguidewire lumen118 and/or thecatheter shaft110 to achieve the desired effect in the desired locations.
• Theballoon104 can include aballoon wall130 that defines aballoon interior146, and can be inflated with aballoon fluid132 to expand from a deflated configuration suitable for advancing thecatheter102 through a patient's vasculature, to an inflated configuration suitable for anchoring thecatheter102 in position relative to thetreatment site106. Stated in another manner, when theballoon104 is in the inflated configuration, theballoon wall130 of theballoon104 is configured to be positioned substantially adjacent to thetreatment site106, i.e. to the vascular lesion(s). It is appreciated that althoughFIG. 1 illustrates theballoon wall130 of theballoon104 being shown spaced apart from thetreatment site106 of theblood vessel108, this is done merely for ease of illustration, and theballoon wall130 of theballoon104 will typically be substantially directly adjacent to thetreatment site106 when the balloon is in the inflated configuration.
• In some embodiments, thelight source124 of thecatheter system100 can be configured to provide sub-millisecond pulses of light from thelight source124, along the light guides122A, to a location within theballoon interior146 of theballoon104, thereby inducing plasma formation in theballoon fluid132 within theballoon interior146 of theballoon104, i.e. via a plasma generator133 (illustrated in phantom) located at a guidedistal end122D of each of the light guides122A. The plasma formation causes rapid bubble formation, and imparts pressure waves upon thetreatment site106. Exemplary plasma-induced bubbles are shown asbubbles134 inFIG. 1.
• Theballoons104 suitable for use in thecatheter systems100 described in detail herein include those that can be passed through the vasculature of a patient when in the deflated configuration. In some embodiments, theballoons104 herein are made from silicone. In other embodiments, theballoons104 herein are made from polydimethylsiloxane (PDMS), polyurethane, polymers such as PEBAX™ material available from Arkema, which has a location at King of Prussia, Pa., USA, nylon, and the like. In some embodiments, theballoons104 can include those having diameters ranging from one millimeter (mm) to 25 mm in diameter. In some embodiments, theballoons104 can include those having diameters ranging from at least 1.5 mm to 12 mm in diameter. In some embodiments, theballoons104 can include those having diameters ranging from at least one mm to five mm in diameter.
• Additionally, in some embodiments, theballoons104 herein can include those having a length ranging from at least five mm to 300 mm. More particularly, in some embodiments, theballoons104 herein can include those having a length ranging from at least eight mm to 200 mm. It is appreciated thatballoons104 of greater length can be positioned adjacent tolarger treatment sites106, and, thus, may be usable for imparting pressure onto and inducing fractures in larger vascular lesions or multiple vascular lesions at precise locations within thetreatment site106.
• Further, theballoons104 herein can be inflated to inflation pressures of between approximately one atmosphere (atm) and 70 atm. In some embodiments, theballoons104 herein can be inflated to inflation pressures of from at least 20 atm to 70 atm. In other embodiments, theballoons104 herein can be inflated to inflation pressures of from at least six atm to 20 atm. In still other embodiments, theballoons104 herein can be inflated to inflation pressures of from at least three atm to 20 atm. In yet other embodiments, theballoons104 herein can be inflated to inflation pressures of from at least two atm to ten atm.
• Still further, theballoons104 herein can include those having various shapes, including, but not to be limited to, a conical shape, a square shape, a rectangular shape, a spherical shape, a conical/square shape, a conical/spherical shape, an extended spherical shape, an oval shape, a tapered shape, a bone shape, a stepped diameter shape, an offset shape, or a conical offset shape. In some embodiments, theballoons104 herein can include a drug eluting coating or a drug eluting stent structure. The drug eluting coating or drug eluting stent can include one or more therapeutic agents including anti-inflammatory agents, anti-neoplastic agents, anti-angiogenic agents, and the like.
• Theballoon fluid132 can be a liquid or a gas.Exemplary balloon fluids132 suitable for use herein can include, but are not limited to one or more of water, saline, contrast medium, fluorocarbons, perfluorocarbons, gases, such as carbon dioxide, and the like. In some embodiments, theballoon fluids132 described can be used as base inflation fluids. In some embodiments, theballoon fluids132 include a mixture of saline to contrast medium in a volume ratio of 50:50. In other embodiments, theballoon fluids132 include a mixture of saline to contrast medium in a volume ratio of 25:75. In still other embodiments, theballoon fluids132 include a mixture of saline to contrast medium in a volume ratio of 75:25. Additionally, theballoon fluids132 suitable for use herein can be tailored on the basis of composition, viscosity, and the like in order to manipulate the rate of travel of the pressure waves therein. In certain embodiments, theballoon fluids132 suitable for use herein are biocompatible. A volume ofballoon fluid132 can be tailored by the chosenlight source124 and the type ofballoon fluid132 used.
• In some embodiments, the contrast agents used in the contrast media herein can include, but are not to be limited to, iodine-based contrast agents, such as ionic or non-ionic iodine-based contrast agents. Some non-limiting examples of ionic iodine-based contrast agents include diatrizoate, metrizoate, iothalamate, and ioxaglate. Some non-limiting examples of non-ionic iodine-based contrast agents include iopamidol, iohexol, ioxilan, iopromide, iodixanol, and ioversol. In other embodiments, non-iodine based contrast agents can be used. Suitable non-iodine containing contrast agents can include gadolinium (III)-based contrast agents. Suitable fluorocarbon and perfluorocarbon agents can include, but are not to be limited to, agents such as the perfluorocarbon dodecafluoropentane (DDFP, C5F12).
• Additionally, theballoon fluids132 herein can include those that include absorptive agents that can selectively absorb light in the ultraviolet region (e.g., at least ten nanometers (nm) to 400 nm), the visible region (e.g., at least 400 nm to 780 nm), or the near-infrared region (e.g., at least 780 nm to 2.5 μm) of the electromagnetic spectrum. Suitable absorptive agents can include those with absorption maxima along the spectrum from at least ten nm to 2.5 μm. Alternatively, theballoon fluids132 can include those that include absorptive agents that can selectively absorb light in the mid-infrared region (e.g., at least 2.5 μm to 15 μm), or the far-infrared region (e.g., at least 15 μm to one mm) of the electromagnetic spectrum. In various embodiments, the absorptive agent can be those that have an absorption maximum matched with the emission maximum of the laser used in the catheter system. By way of non-limiting examples, various lasers described herein can include neodymium:yttrium-aluminum-garnet (Nd:YAG—emission maximum=1064 nm) lasers, holmium:YAG (Ho:YAG—emission maximum=2.1 μm) lasers, or erbium:YAG (Er:YAG—emission maximum=2.94 μm) lasers. In some embodiments, the absorptive agents used herein can be water soluble. In other embodiments, the absorptive agents used herein are not water soluble. In some embodiments, the absorptive agents used in theballoon fluids132 herein can be tailored to match the peak emission of thelight source124. Variouslight sources124 having emission wavelengths of at least ten nanometers to one millimeter are discussed elsewhere herein.
• It is appreciated that thecatheter system100 and/or thelight guide bundle122 disclosed herein can include any number oflight guides122A in optical communication with thelight source124 at theproximal portion114, and with theballoon fluid132 within theballoon interior146 of theballoon104 at thedistal portion116. For example, in some embodiments, thecatheter system100 and/or thelight guide bundle122 can include from onelight guide122A to fivelight guides122A. In other embodiments, thecatheter system100 and/or thelight guide bundle122 can include from fivelight guides122A to fifteenlight guides122A. In yet other embodiments, thecatheter system100 and/or thelight guide bundle122 can include from tenlight guides122A to thirtylight guides122A. Alternatively, in still other embodiments, thecatheter system100 and/or thelight guide bundle122 can include greater than 30light guides122A.
• The light guides122A herein can include an optical fiber or flexible light pipe. The light guides122A herein can be thin and flexible and can allow light signals to be sent with very little loss of strength. The light guides122A herein can include a core surrounded by a cladding about its circumference. In some embodiments, the core can be a cylindrical core or a partially cylindrical core. The core and cladding of the light guides122A can be formed from one or more materials, including but not limited to one or more types of glass, silica, or one or more polymers. The light guides122A may also include a protective coating, such as a polymer. It is appreciated that the index of refraction of the core will be greater than the index of refraction of the cladding.
• Eachlight guide122A can guide light along its length from a proximal portion, i.e. a guideproximal end122P, to a distal portion, i.e. the guidedistal end122D, having at least one optical window (not shown) that is positioned within theballoon interior146. The light guides122A can create a light path as a portion of an optical network including thelight source124. The light path within the optical network allows light to travel from one part of the network to another. Both the optical fiber and the flexible light pipe can provide a light path within the optical networks herein.
• Further, the light guides122A herein can assume many configurations about and/or relative to thecatheter shaft110 of thecatheters102 described herein. In some embodiments, the light guides122A can run parallel to thelongitudinal axis144 of thecatheter shaft110. In some embodiments, the light guides122A can be physically coupled to thecatheter shaft110. In other embodiments, the light guides122A can be disposed along a length of an outer diameter of thecatheter shaft110. In yet other embodiments, the light guides122A herein can be disposed within one or more light guide lumens within thecatheter shaft110.
• Additionally, it is further appreciated that the light guides122A can be disposed at any suitable positions about the circumference of theguidewire lumen118 and/or thecatheter shaft110, and the guidedistal end122D of each of the light guides122A can be disposed at any suitable longitudinal position relative to the length of theballoon104 and/or relative to the length of theguidewire lumen118 to more effectively and precisely impart pressure waves for purposes of disrupting the vascular lesions at thetreatment site106.
• Further, the light guides122A herein can include one or morephotoacoustic transducers154, where eachphotoacoustic transducer154 can be in optical communication with thelight guide122A within which it is disposed. In some embodiments, thephotoacoustic transducers154 can be in optical communication with the guidedistal end122D of thelight guide122A. Additionally, in such embodiments, thephotoacoustic transducers154 can have a shape that corresponds with and/or conforms to the guidedistal end122D of thelight guide122A.
• Thephotoacoustic transducer154 is configured to convert light energy into an acoustic wave at or near the guidedistal end122D of thelight guide122A. It is appreciated that the direction of the acoustic wave can be tailored by changing an angle of the guidedistal end122D of thelight guide122A.
• It is further appreciated that thephotoacoustic transducers154 disposed at the guidedistal end122D of thelight guide122A herein can assume the same shape as the guidedistal end122D of thelight guide122A. For example, in certain non-exclusive embodiments, thephotoacoustic transducer154 and/or the guidedistal end122D can have a conical shape, a convex shape, a concave shape, a bulbous shape, a square shape, a stepped shape, a half-circle shape, an ovoid shape, and the like. It is also appreciated that thelight guide122A can further include additionalphotoacoustic transducers154 disposed along one or more side surfaces of the length of thelight guide122A.
• The light guides122A described herein can further include one or more diverting features or “diverters” (not shown inFIG. 1) within thelight guide122A that are configured to direct light to exit thelight guide122A toward a side surface e.g., at or near the guidedistal end122D of thelight guide122A, and toward theballoon wall130. A diverting feature can include any feature of the system herein that diverts light from thelight guide122A away from its axial path toward a side surface of thelight guide122A. Additionally, the light guides122A can each include one or more light windows disposed along the longitudinal or axial surfaces of eachlight guide122A and in optical communication with a diverting feature. Stated in another manner, the diverting features herein can be configured to direct light in thelight guide122A toward a side surface, e.g., at or near the guidedistal end122D, where the side surface is in optical communication with a light window. The light windows can include a portion of thelight guide122A that allows light to exit thelight guide122A from within thelight guide122A, such as a portion of thelight guide122A lacking a cladding material on or about thelight guide122A.
• Examples of the diverting features suitable for use herein include a reflecting element, a refracting element, and a fiber diffuser. Additionally, the diverting features suitable for focusing light away from the tip of the light guides122A herein can include, but are not to be limited to, those having a convex surface, a gradient-index (GRIN) lens, and a mirror focus lens. Upon contact with the diverting feature, the light is diverted within thelight guide122A to thephotoacoustic transducer154 that is in optical communication with a side surface of thelight guide122A. As noted, thephotoacoustic transducer154 then converts light energy into an acoustic wave that extends away from the side surface of thelight guide122A.
• The source manifold136 can be positioned at or near theproximal portion114 of thecatheter system100. The source manifold136 can include one or more proximal end openings that can receive the one or more light guides122A of thelight guide bundle122, theguidewire112, and/or aninflation conduit140 that is coupled in fluid communication with thefluid pump138. Thecatheter system100 can also include thefluid pump138 that is configured to inflate theballoon104 with theballoon fluid132, i.e. via theinflation conduit140, as needed.
• As noted above, in the embodiment illustrated inFIG. 1, thesystem console123 includes one or more of thelight source124, thepower source125, thesystem controller126, theGUI127, themultiplexer128, and themultiplexer alignment system142. Alternatively, thesystem console123 can include more components or fewer components than those specifically illustrated inFIG. 1. For example, in certain non-exclusive alternative embodiments, thesystem console123 can be designed without theGUI127. Still alternatively, one or more of thelight source124, thepower source125, thesystem controller126, theGUI127, themultiplexer128 and themultiplexer alignment system142 can be provided within thecatheter system100 without the specific need for thesystem console123.
• Additionally, as shown, thesystem console123, and the components included therewith, is operatively coupled to thecatheter102, thelight guide bundle122, and the remainder of thecatheter system100. For example, in some embodiments, as illustrated inFIG. 1, thesystem console123 can include a console connection aperture148 (also sometimes referred to generally as a “socket”) by which thelight guide bundle122 is mechanically coupled to thesystem console123. In such embodiments, thelight guide bundle122 can include a guide coupling housing150 (also sometimes referred to generally as a “ferrule”) that houses a portion, e.g., the guideproximal end122P, of each of the light guides122A. Theguide coupling housing150 is configured to fit and be selectively retained within theconsole connection aperture148 to provide the desired mechanical coupling between thelight guide bundle122 and thesystem console123.
• Further, thelight guide bundle122 can also include a guide bundler152 (or “shell”) that brings each of the individual light guides122A closer together so that the light guides122A and/or thelight guide bundle122 can be in a more compact form as it extends with thecatheter102 into theblood vessel108 during use of thecatheter system100.
• As provided herein, thelight source124 can be selectively and/or alternatively coupled in optical communication with each of the light guides122A, i.e. to the guideproximal end122P of each of the light guides122A, in thelight guide bundle122. In particular, thelight source124 is configured to generate light energy in the form of asource beam124A, e.g., a pulsed source beam, that can be selectively and/or alternatively directed to and received by each of the light guides122A in thelight guide bundle122 in any desired combination, order, sequence and/or pattern. More specifically, as described in greater detail herein below, thesource beam124A from thelight source124 is directed through themultiplexer128 such that individual guide beams124B (or “multiplexed beams”) can be selectively and/or alternatively directed into and received by each of the light guides122A in thelight guide bundle122. In particular, each pulse of thelight source124, i.e. each pulse of thesource beam124A, can be directed through themultiplexer128 to generate one or more separate guide beams1248 (only one is shown inFIG. 1) that are selectively and/or alternatively directed to one or more of the light guides122A in thelight guide bundle122.
• Thelight source124 can have any suitable design. In certain embodiments, as noted above, thelight source124 can be configured to provide sub-millisecond pulses of light from thelight source124 that are focused onto a small spot, i.e. through the use of themultiplexer alignment system142, in order to couple it into the guideproximal end122P of thelight guide122A. Such pulses of light energy are then directed along the light guides122A to a location within theballoon104, thereby inducing plasma formation in theballoon fluid132 within theballoon interior146 of theballoon104. In particular, the light energy emitted at the guidedistal end122D of thelight guide122A energizes theplasma generator133 to form the plasma within theballoon fluid132 within theballoon interior146. The plasma formation causes rapid bubble formation, and imparts pressure waves upon thetreatment site106. In such embodiments, the sub-millisecond pulses of light from thelight source124 can be delivered to thetreatment site106 at a frequency of between approximately one hertz (Hz) and 5000 Hz. In some embodiments, the sub-millisecond pulses of light from thelight source124 can be delivered to thetreatment site106 at a frequency of between approximately 30 Hz and 1000 Hz. In other embodiments, the sub-millisecond pulses of light from thelight source124 can be delivered to thetreatment site106 at a frequency of between approximately ten Hz and 100 Hz. In yet other embodiments, the sub-millisecond pulses of light from thelight source124 can be delivered to thetreatment site106 at a frequency of between approximately one Hz and 30 Hz. Alternatively, the sub-millisecond pulses of light can be delivered to thetreatment site106 at a frequency that can be greater than 5000 Hz.
• It is appreciated that although thelight source124 is typically utilized to provide pulses of light energy, thelight source124 can still be described as providing asingle source beam124A, i.e. a single pulsed source beam.
• Thelight sources124 suitable for use herein can include various types of light sources including lasers and lamps. Suitable lasers can include short pulse lasers on the sub-millisecond timescale. In some embodiments, thelight source124 can include lasers on the nanosecond (ns) timescale. The lasers can also include short pulse lasers on the picosecond (ps), femtosecond (fs), and microsecond (us) timescales. It is appreciated that there are many combinations of laser wavelengths, pulse widths and energy levels that can be employed to achieve plasma in theballoon fluid132 of thecatheters102 described herein. In various embodiments, the pulse widths can include those falling within a range including from at least ten ns to 200 ns. In some embodiments, the pulse widths can include those falling within a range including from at least 20 ns to 100 ns. In other embodiments, the pulse widths can include those falling within a range including from at least one ns to 500 ns.
• Additionally, exemplary nanosecond lasers can include those within the UV to IR spectrum, spanning wavelengths of about ten nanometers (nm) to one millimeter (mm). In some embodiments, thelight sources124 suitable for use in thecatheter systems100 herein can include those capable of producing light at wavelengths of from at least 750 nm to 2000 nm. In other embodiments, thelight sources124 can include those capable of producing light at wavelengths of from at least 700 nm to 3000 nm. In still other embodiments, thelight sources124 can include those capable of producing light at wavelengths of from at least 100 nm to ten micrometers (μm). Nanosecond lasers can include those having repetition rates of up to 200 kHz. In some embodiments, the laser can include a Q-switched thulium:yttrium-aluminum-garnet (Tm:YAG) laser. In other embodiments, the laser can include a neodymium:yttrium-aluminum-garnet (Nd:YAG) laser, holmium:yttrium-aluminum-garnet (Ho:YAG) laser, erbium:yttrium-aluminum-garnet (Er:YAG) laser, excimer laser, helium-neon laser, carbon dioxide laser, as well as doped, pulsed, fiber lasers.
• Thecatheter systems100 disclosed herein can generate pressure waves having maximum pressures in the range of at least one megapascal (MPa) to 100 MPa. The maximum pressure generated by aparticular catheter system100 will depend on thelight source124, the absorbing material, the bubble expansion, the propagation medium, the balloon material, and other factors. In some embodiments, thecatheter systems100 herein can generate pressure waves having maximum pressures in the range of at least two MPa to 50 MPa. In other embodiments, thecatheter systems100 herein can generate pressure waves having maximum pressures in the range of at least two MPa to 30 MPa. In yet other embodiments, thecatheter systems100 herein can generate pressure waves having maximum pressures in the range of at least 15 MPa to 25 MPa.
• The pressure waves described herein can be imparted upon thetreatment site106 from a distance within a range from at least 0.1 millimeters (mm) to 25 mm extending radially from the light guides122A when thecatheter102 is placed at thetreatment site106. In some embodiments, the pressure waves can be imparted upon thetreatment site106 from a distance within a range from at least ten mm to 20 mm extending radially from the light guides122A when thecatheter102 is placed at thetreatment site106. In other embodiments, the pressure waves can be imparted upon thetreatment site106 from a distance within a range from at least one mm to ten mm extending radially from the light guides122A when thecatheter102 is placed at thetreatment site106. In yet other embodiments, the pressure waves can be imparted upon thetreatment site106 from a distance within a range from at least 1.5 mm to four mm extending radially from the light guides122A when thecatheter102 is placed at thetreatment site106. In some embodiments, the pressure waves can be imparted upon thetreatment site106 from a range of at least two MPa to 30 MPa at a distance from 0.1 mm to ten mm. In some embodiments, the pressure waves can be imparted upon thetreatment site106 from a range of at least two MPa to 25 MPa at a distance from 0.1 mm to ten mm.
• Thepower source125 is electrically coupled to and is configured to provide necessary power to each of thelight source124, thesystem controller126, theGUI127, themultiplexer128, and themultiplexer alignment system142. Thepower source125 can have any suitable design for such purposes.
• As noted, thesystem controller126 is electrically coupled to and receives power from thepower source125. Additionally, thesystem controller126 is coupled to and is configured to control operation of each of thelight source124, theGUI127, themultiplexer128 and themultiplexer alignment system142. Thesystem controller126 can include one or more processors or circuits for purposes of controlling the operation of at least thelight source124, theGUI127, themultiplexer128 and themultiplexer alignment system142. For example, thesystem controller126 can control thelight source124 for generating pulses of light energy as desired, e.g., at any desired firing rate. Additionally, thesystem controller126 can control themultiplexer alignment system142 to map out and accurately ensure the desired optical coupling between thelight source124 and the light guides122A. Substantially simultaneously and/or subsequently, thesystem controller126 can control themultiplexer128 so that the light energy from thelight source124, i.e. thesource beam124A, can be selectively and/or alternatively directed to each of the light guides122A, i.e. in the form of individual guide beams1248, in a desired manner. Additionally, thesystem controller126 can further be configured to control operation of other components of thecatheter system100, e.g., the positioning of thecatheter102 adjacent to thetreatment site106, the inflation of theballoon104 with theballoon fluid132, etc. Further, or in the alternative, thecatheter system100 can include one or more additional controllers that can be positioned in any suitable manner for purposes of controlling the various operations of thecatheter system100.
• TheGUI127 is accessible by the user or operator of thecatheter system100. Additionally, theGUI127 is electrically connected to thesystem controller126. With such design, theGUI127 can be used by the user or operator to ensure that thecatheter system100 is employed as desired to impart pressure onto and induce fractures into the vascular lesions at thetreatment site106. Additionally, theGUI127 can provide the user or operator with information that can be used before, during and after use of thecatheter system100. In one embodiment, theGUI127 can provide static visual data and/or information to the user or operator. In addition, or in the alternative, theGUI127 can provide dynamic visual data and/or information to the user or operator, such as video data or any other data that changes over time, e.g., during use of thecatheter system100. Further, in various embodiments, theGUI127 can include one or more colors, different sizes, varying brightness, etc., that may act as alerts to the user or operator. Additionally, or in the alternative, theGUI127 can provide audio data or information to the user or operator. It is appreciated that the specifics of theGUI127 can vary depending upon the design requirements of thecatheter system100, or the specific needs, specifications and/or desires of the user or operator.
• As provided herein, themultiplexer128 is configured to selectively and/or alternatively direct light energy from thelight source124 to each of the light guides122A in thelight guide bundle122. More particularly, themultiplexer128 is configured to receive light energy from a singlelight source124, e.g., asingle source beam124A from a single laser source, and selectively and/or alternatively direct such light energy in the form of individual guide beams124B to each of the light guides122A in thelight guide bundle122 in any desired combination, sequence, order and/or pattern. As such, themultiplexer128 enables a singlelight source124 to be channeled simultaneously and/or sequentially through a plurality oflight guides122A such that thecatheter system100 is able to impart pressure onto and induce fractures in vascular lesions at thetreatment site106 within or adjacent to a vessel wall of theblood vessel108 in a desired manner. Additionally, as shown, thecatheter system100 can include one or moreoptical elements147 for purposes of directing the light energy, e.g., thesource beam124A, from thelight source124 to themultiplexer128.
• Additionally, as provided herein, themultiplexer alignment system142 is configured to ensure that themultiplexer128 is precisely and accurately aligned so that the individual guide beams1248 are optically coupled onto the guideproximal end122P of the desiredlight guide122A. More specifically, in various embodiments, themultiplexer alignment system142 provides an effective means to improve optical coupling between thelight source124 and the guideproximal end122P of each of the light guides122A within thelight guide bundle122 by measuring coupling efficiency and determining the optimal parameters to trigger firing of thelight source124. As described herein, in some embodiments, themultiplexer alignment system142 can be configured to operate continuously during coincident use of themultiplexer128. Additionally, or in the alternative, in other embodiments, themultiplexer alignment system142 can be configured to actively scan each of the light guides122A of thelight guide bundle122 to find and map out the X-Y location for eachlight guide122A that provides optimal coupling, before the firing of thelight source124 and the operation of themultiplexer128. In such alternative embodiments, thecatheter system100, e.g., thesystem controller126, could be configured to store the information from themultiplexer alignment system142 and use the mapped out locations for eachlight guide122A for real-time firing of thelight source124 and operation of themultiplexer128.
• As described herein, themultiplexer128 and/or themultiplexer alignment system142 can have any suitable designs for purposes of precisely, selectively and/or alternatively directing the light energy from thelight source124 to each of the light guides122A of thelight guide bundle122. Various non-exclusive alternative embodiments of themultiplexer128 and themultiplexer alignment system142 are described in detail herein below.
• FIG. 2 is a simplified schematic illustration of a portion of an embodiment of thecatheter system200 including an embodiment of themultiplexer228 and themultiplexer alignment system242. More particularly,FIG. 2 illustrates alight guide bundle222 including a plurality oflight guides222A; alight source224; asystem controller226 includingcontrol electronics226A andsignal processing electronics226B; themultiplexer228 that receives light energy in the form of asource beam224A, e.g., a pulsed source beam and/or a semi-continuous wave source beam, from thelight source224 and selectively and/or alternatively directs the light energy in the form of individual guide beams224B onto a guideproximal end222P of each of the plurality of the light guides222A; and themultiplexer alignment system242 that utilizes light energy from a secondlight source270 in the form of aprobe source beam270A to probe a face of thelight guide bundle222 and/or the guideproximal end222P of each of the light guides222A in thelight guide bundle222 as a means to improve optical coupling between the guide beams224B and the guideproximal end222P of each of the light guides222A. Thelight guide bundle222 and/or the light guides222A, and thelight source224 are substantially similar in design and function as described in detail herein above. Accordingly, such components will not be described in detail in relation to the embodiment illustrated inFIG. 2. It is further appreciated that certain components of thesystem console123 illustrated and described above in relation toFIG. 1, e.g., thepower source125 and theGUI127, are not illustrated inFIG. 2 for purposes of simplicity and ease of illustration, but would typically be included in many embodiments.
• As illustrated, in some embodiments, thecontrol electronics226A and thesignal processing electronics226B can be included as part of thesystem controller226. Alternatively, thecontrol electronics226A and/or thesignal processing electronics226B can be provided independently of thesystem controller226 and can be in electrical communication with thesystem controller226.
• It is appreciated that thelight guide bundle222 can include any suitable number of light guides222A, which can be positioned and/or oriented relative to one another in any suitable manner, e.g., to best align the plurality oflight guides222A relative to themultiplexer228 and/or themultiplexer alignment system242. For example, in the embodiment illustrated inFIG. 2, thelight guide bundle222 includes fourlight guides222A that are aligned in a linear arrangement relative to one another. Alternatively, thelight guide bundle222 can include a different number of light guides222A, i.e. greater than four or fewer than fourlight guides222A, and/or the light guides222A can be arranged in a different manner relative to one another.
• As shown inFIG. 2, each of the light guides222A includes aplasma generator233 that is positioned at the guidedistal end222D of thelight guide222A.
• Additionally, as illustrated, the guideproximal end222P of each of the plurality oflight guides222A is retained within aguide coupling housing250, i.e. withinguide coupling slots256 that are formed into theguide coupling housing250. In various embodiments, theguide coupling housing250 is configured to be selectively coupled to the system console123 (illustrated inFIG. 1) so that theguide coupling slots256, and thus the light guides222A, are maintained in a desired fixed position relative to themultiplexer228 and themultiplexer alignment system242 during use of thecatheter system200. In some embodiments, theguide coupling slots256 are provided in the form of V-grooves, such as in a V-groove ferrule block commonly used in multichannel fiber optics communication systems. Alternatively, theguide coupling slots256 can have another suitable design.
• It is appreciated that theguide coupling housing250 can have any suitable number ofguide coupling slots256, which can be positioned and/or oriented relative to one another in any suitable manner, e.g., to best align theguide coupling slots256 and thus the light guides222A relative to themultiplexer228 and themultiplexer alignment system242. In the embodiment illustrated inFIG. 2, theguide coupling housing250 includes fourguide coupling slots256 that are spaced apart in a linear arrangement relative to one another, with precise interval spacing between adjacentguide coupling slots256. Thus, in such embodiment, theguide coupling housing250 is capable of retaining the guideproximal end222P of up to fourlight guides222A. Alternatively, theguide coupling housing250 can have a different number ofguide coupling slots256, i.e. greater than four or fewer than fourguide coupling slots256, and/or theguide coupling slots256 can be arranged in a different manner relative to one another.
• As noted above, themultiplexer228 is configured to receive light energy in the form of thesource beam224A from thelight source224 and selectively and/or alternatively direct the light energy in the form of individual guide beams224B onto the guideproximal end222P of each of the light guides222A. As such, as shown inFIG. 2, themultiplexer228 is operatively and/or optically coupled in optical communication to thelight guide bundle222, i.e. to the plurality oflight guides222A.
• The design of themultiplexer228 can be varied depending on the requirements of thecatheter system200, the relative positioning of the light guides222A, and/or to suit the desires of the user or operator of thecatheter system200. In the embodiment illustrated inFIG. 2, themultiplexer228 includes one or more of amultiplexer base258, amultiplexer stage260, astage mover262, aredirector264,coupling optics266, and afirst beamsplitter268, which are used in conjunction with thesystem controller226, i.e. thecontrol electronics226A and/or thesignal processing electronics226B, and themultiplexer alignment system242 as described in detail herein. Alternatively, themultiplexer228 can include more components or fewer components than those specifically illustrated inFIG. 2.
• Additionally, as noted above, themultiplexer alignment system242 is configured to probe the face of the light guide bundle222 (i.e. the face of the guide coupling housing250) and/or the guideproximal end222P of each of the light guides222A in thelight guide bundle222 as a means to improve optical coupling between the guide beams224B and the guideproximal end222P of each of the light guides222A.
• The design of themultiplexer alignment system242 can be varied depending on the requirements of thecatheter system200, the relative positioning of the light guides222A, and/or to suit the desires of the user or operator of thecatheter system200. In the embodiment illustrated inFIG. 2, themultiplexer alignment system242 includes one or more of the secondlight source270, thefirst beamsplitter268, asecond beamsplitter272, anoptical element274, aphotodetector276 and anamplifier278, which are used in conjunction with thesystem controller226, i.e. thecontrol electronics226A and/or thesignal processing electronics226B, and themultiplexer228. As described in detail herein, the secondlight source270 provides light energy in the form of theprobe source beam270A that is directed to scan across the guideproximal end222P of each of the light guides222A during a mapping process. As such, as shown inFIG. 2, themultiplexer alignment system242 and/or the secondlight source270 is operatively and/or optically coupled in optical communication to thelight guide bundle222, i.e. to the plurality oflight guides222A. Alternatively, themultiplexer alignment system242 can include more components or fewer components than those specifically illustrated inFIG. 2.
• During use of thecatheter system200, themultiplexer base258 is fixed in position relative to thelight source224 and the light guides222A. Additionally, in this embodiment, themultiplexer stage260 is movably supported on themultiplexer base258. More particularly, in the embodiment shown inFIG. 2, thestage mover262 is configured to move themultiplexer stage260 along a linear path relative to themultiplexer base258. Further, in certain embodiments, thestage mover262 can be configured to move themultiplexer stage260 linearly relative to themultiplexer base258 along one or more stage guides263 that are coupled to themultiplexer base258.
• As shown inFIG. 2, theredirector264, thecoupling optics266 and thefirst beamsplitter268 of themultiplexer228 are mounted on and/or retained by themultiplexer stage260. Thus, movement of themultiplexer stage260 relative to themultiplexer base258 results in corresponding movement of theredirector264, thecoupling optics266 and thefirst beamsplitter268 relative to the fixedmultiplexer base258. Further, with the light guides222A being fixed in position relative to themultiplexer base258, movement of themultiplexer stage260 results in corresponding movement of theredirector264, thecoupling optics266 and thefirst beamsplitter268 relative to the light guides222A.
• Additionally, as shown inFIG. 2, thefirst beamsplitter268, thesecond beamsplitter272, theoptical element274, thephotodetector276 and theamplifier278 of themultiplexer alignment system242 are also mounted on and/or retained by themultiplexer stage260. Thus, movement of themultiplexer stage260 relative to themultiplexer base258 results in corresponding movement of thefirst beamsplitter268, thesecond beamsplitter272, theoptical element274, thephotodetector276 and theamplifier278 relative to the fixedmultiplexer base258. Further, with the light guides222A being fixed in position relative to themultiplexer base258, movement of themultiplexer stage260 results in corresponding movement of thefirst beamsplitter268, thesecond beamsplitter272, theoptical element274, thephotodetector276 and theamplifier278 relative to the light guides222A. It is understood that in this, and various other embodiments, thephotodetector276 can include additional focusing or collecting optics.
• In various embodiments, in conjunction with use of themultiplexer alignment system242, themultiplexer228 is configured to precisely align thecoupling optics266 with each of the light guides222A such that thesource beam224A generated by thelight source224 can be precisely directed and focused by themultiplexer228 as acorresponding guide beam224B onto the guideproximal end222P of each of the light guides222A. In its simplest form, as shown inFIG. 2, themultiplexer228 uses a precision mechanism, i.e. thestage mover262, to translate thecoupling optics266 along a linear path. This approach requires a single degree of freedom. In certain embodiments, the linear translation mechanism, i.e. thestage mover262, and/or themultiplexer stage260 can be electronically controlled to line the beam path of theguide beam224B sequentially with each individuallight guide222A that is retained, in part, within theguide coupling housing250 during a scanning process. Alternatively, thestage mover262 can be equipped with mechanical stops so that thecoupling optics266 can be precisely aligned with the position of each of the light guides222A.
• In this embodiment, thestage mover262 can have any suitable design for purposes of moving themultiplexer stage260 in a linear manner relative to themultiplexer base258. More particularly, thestage mover262 can be any suitable type of linear translation mechanism.
• As noted above, themultiplexer stage260 is configured to carry the necessary optics, e.g., theredirector264 and thecoupling optics266, to direct and focus the light energy generated by thelight source224 to eachlight guide222A for optimal coupling. With such design, the low divergence of theguide beam224A over the short distance of motion of the translatedmultiplexer stage260 has minimum impact on coupling efficiency to thelight guide222A.
• Additionally, in this embodiment, thesource beam224A being directed toward themultiplexer228 initially impinges on theredirector264, which is configured to redirect thesource beam224A toward thecoupling optics266. In some embodiments, theredirector264 redirects thesource beam224A by approximately 90 degrees toward thecoupling optics266. Alternatively, theredirector264 can redirect thesource beam224A by more than 90 degrees or less than 90 degrees toward thecoupling optics266. Thus, theredirector264 that is mounted on themultiplexer stage260 is configured to direct thesource beam224A through thecoupling optics266 so that individual guide beams224B are focused into the individual light guides222A in theguide coupling housing250.
• Thecoupling optics266 can have any suitable design for purposes of focusing the individual guide beams224B to each of the light guides222A. In one embodiment, thecoupling optics266 includes two lenses that are specifically configured to focus the individual guide beams224B as desired. Alternatively, thecoupling optics266 can have another suitable design.
• In certain non-exclusive alternative embodiments, the steering of thesource beam224A so that it is properly directed and focused to each of the light guides222A can be accomplished using mirrors that are attached to optomechanical scanners, X-Y galvanometers or other multi-axis beam steering devices.
• It is appreciated that the operation of aligning the beam path of theguide beam224B with a selectedlight guide222A assumes that the motion axis is perfectly parallel to the axis of thelight guide bundle222 and/or the individual light guides222A. In some embodiments, a vertical dither can be included to track this axis.
• As shown inFIG. 2, theprobe source beam270A from thesecond energy source270 is initially directed toward thesecond beamsplitter272, from where at least a portion of theprobe source beam270A is directed onward toward theoptical element274. Further, as shown in the embodiment illustrated inFIG. 2, themultiplexer alignment system242, in conjunction with themultiplexer228, is configured to precisely align theoptical element274, e.g., a coupling lens, relative to each of the light guides222A such that theprobe source beam270A generated by the secondlight source270 can be precisely directed and focused by themultiplexer alignment system242 to scan across the face of theguide coupling housing250 and/or the guideproximal end222P of each of the light guides222A.
• Additionally, as illustrated, each of the individual guide beams224B and theprobe source beam270A are all directed to impinge on thefirst beamsplitter268 prior to being directed toward the light guides222A. Stated in another manner, in this embodiment, thefirst beamsplitter268 is positioned in the optical path of the individual guide beams224B between the coupling optics and the light guides222A, and thefirst beamsplitter268 is also positioned in the optical path of theprobe source beam270A between theoptical element274 and the light guides222A. In certain embodiments, thefirst beamsplitter268 can be a dichroic beamsplitter that is configured to transmit light having wavelengths longer than a predetermined cutoff wavelength, and reflect (and redirect, e.g., by approximately 90 degrees or another suitable amount) light having wavelengths shorter than the predetermined cutoff wavelength. For example, in some embodiments, thelight source224 can be a pulsed infrared laser source such that the individual guide beams224B have a wavelength in the infrared light range; and the secondlight source270 can be a low-power, visible light continuous wave laser source such that theprobe source beam270A has a wavelength in the visible light range. In such embodiments, thefirst beamsplitter268 can have a predetermined cutoff wavelength such that the individual guide beams224B will be transmitted through thefirst beamsplitter268 toward the light guides222A, while theprobe source beam270A will be reflected by thefirst beamsplitter268 and redirected toward the light guides222A. Thus, as shown, thefirst beamsplitter268 allows the path of theprobe source beam270A to be effectively combined with the path of the individual guide beams224B. Alternatively, thefirst beamsplitter268 and/or thelight source224 and the secondlight source270 can have another suitable design.
• Additionally, or in the alternative, in one embodiment, the secondlight source270 can include and/or incorporate high-speed modulation in order to allow phase-sensitive (lock-in) detection. In such embodiment, it is appreciated that the modulation must be much faster than dwell time on target as theprobe source beam270A from the secondlight source270 scans across the face of theguide coupling housing250 and/or the guideproximal end222P of each of the light guides222A.
• During operation of thecatheter system200, thecontrol electronics226A drive thestage mover262 to move themultiplexer stage260 in a desired manner so that theprobe source beam270A and the individual guide beams224B scan across the face of theguide coupling housing250 and/or the guideproximal end222P of each of the light guides222A. Additionally, theoptical element274 of themultiplexer alignment system242 is used to focus theprobe source beam270A down to form a spot that will couple to the guideproximal end222P of eachlight guide222A similarly to the individual guide beams224B as directed and focused by theredirector264 and thecoupling optics266 of themultiplexer228. In some embodiments, the design and focal length of theoptical element274 may be configured to create a spot size for theprobe source beam270A that is larger than the spot size for the individual guide beams224B. This can be used to cover more of the guideproximal end222P of eachlight guide222 as the scanning occurs.
• In certain embodiments, as shown inFIG. 2, thecatheter system200 is controlled such that theprobe source beam270A is slightly offset from the individual guide beams224B as they are scanned across the face of theguide coupling housing250. More particularly, in such embodiments, theoptical element274 and thecoupling optics266 can be configured and/or positioned such that theprobe source beam270A slightly leads or is slightly ahead of the individual guide beams224B during the scanning process. Stated in another manner, thecoupling optics266 in themultiplexer228 and theoptical element274 of themultiplexer alignment system242 are aligned such that the spot from theguide beam224B is formed a controlled distance lagging the spot from theprobe source beam270A.
• Additionally, during operation, the secondlight source270 is configured to operate continuously as themultiplexer228 and themultiplexer alignment system242 scan across the face of theguide coupling housing250. In particular, the spot from theprobe source beam270A of the secondlight source270 is focused by theoptical element274 onto the end face of theguide coupling housing250 and the faces of the individual light guides222A during the scanning process. During the scanning process, at least a portion of the light in the focused spot from theprobe source beam270A scatters off the faces of theguide coupling housing250 and the individual light guides222A, and is directed back toward thefirst beamsplitter268 as abackscattered energy beam270B. Thebackscattered energy beam270B is reflected off of and redirected by thefirst beamsplitter268 toward theoptical element274 where it is collected and collimated. Thus, theoptical element274 acts to both form a spot from thesecond energy source270 as it is focused toward and onto theguide coupling housing250, and to collect the light scattered from theprobe source beam270A impinging on theguide coupling housing250 and/or the faces of the light guides222A, i.e. thebackscattered energy beam270B, and collimate such light.
• Further, or in the alternative, in certain embodiments, the guideproximal end222P of each of the light guides222A can be coated with an anti-reflective coating at the wavelength of the guide beams224B and a highly-reflective coating at the wavelength of theprobe source beam270A. With such design, the degree of backscatter for theprobe source beam270A, i.e. to provide thebackscattered energy beam270B, can be improved.
• Theoptical element274 then focuses the backscatteredenergy beam270B back toward thesecond beamsplitter272. More specifically, as shown, thesecond beamsplitter272 is not only positioned in the optical path of theprobe source beam270A from the secondlight source270, but thesecond beamsplitter272 is also positioned in the optical path of thebackscattered energy beam270B between theoptical element274 and thephotodetector276. In one embodiment, thesecond beamsplitter272 can be a 10/90 beamsplitter that is configured to transmit ten percent of the incident beam and redirect or reflect 90 percent of the incident beam. This allows a small percentage of the incident light from the backscatteredenergy beam270B to pass through and reflects most of the light returned as thebackscattered energy beam270B onto thephotodetector276. Thus, theoptical element274 effectively couples at least a portion of the light energy scattered from the faces of theguide coupling housing250 and the individual light guides222A, i.e. in the form of thebackscattered energy beam270B, onto thephotodetector276. With such design, a significant portion of the visible light scattered from the faces of theguide coupling housing250 and the individual light guides222A is collected by thephotodetector276. It is appreciated that the small percentage of transmitted light back through thesecond beamsplitter272 is easily compensated for by increasing the power of thesecond energy source270. This technique increases the signal-to-noise ratio (SNR) of the detection system. Alternatively, thesecond beamsplitter272 can have another suitable design. For example, in certain non-exclusive alternative embodiments, thesecond beamsplitter272 can be a 1/99 beamsplitter, a 5/95 beamsplitter, a 20/80 beamsplitter, a 30/70 beamsplitter, a 40/60 beamsplitter, a 50/50 beamsplitter, a 60/40 beamsplitter, a 70/30 beamsplitter, an 80/20 beamsplitter, a 90/10 beamsplitter, a 95/5 beamsplitter, a 99/1 beamsplitter, or another suitable design.
• Additionally, in some embodiments, thephotodetector276 then generates a signal that is based on the portion of the visible light scattered from the faces of theguide coupling housing250 and the individual light guides222A, i.e. the portion of thebackscattered energy beam270B, which has been collected by thephotodetector276. As shown inFIG. 2, the signal from thephotodetector276 is then directed toward theamplifier278 where the signal from thephotodetector276 is amplified. The amplified signal is thus utilized, e.g., within thesignal processing electronics226B, to determine the intensity of the backscattered energy beam2708.
• As described herein, the design of thesecond beamsplitter272 should be such that at least a sufficient portion of thebackscattered energy beam270B needs to be directed onto thephotodetector276 to generate a strong enough signal to be effectively evaluated by thesignal processing electronics226B.
• Additionally, it is appreciated that thephotodetector276 can have any suitable design for purposes of effectively collecting the portion of the visible light, i.e. the backscatteredbeam270B, scattered from the faces of theguide coupling housing250 and the individual light guides222A. For example, in one non-exclusive embodiment, thephotodetector276 can include a narrow band spectral filter that is configured to match the wavelength of theprobe source beam270A from the secondlight source270 so as to reduce background noise.
• As theprobe source beam270A scans across the face of theguide coupling housing250, the local reflectance creates strong backscatter and, thus, a large signal. For example, when the spot from theprobe source beam270A is far away from the guideproximal end222P of the light guides222A, the amount of backscatter, and thus the corresponding signal, will be high. As the spot from theprobe source beam270A comes into alignment with the guideproximal end222P and thus the fiber core, more light will be coupled into the light guide and the backscatter signal will decrease. When the signal reaches a relative minimum, it is an indication of precise optimal coupling. Stated in another manner, as described herein, when the intensity of thebackscattered energy beam270B is determined to be at a local minimum, i.e. by thesignal processing electronics226B, then it is determined that it is an appropriate time to fire thelight source224 so that aguide beam224B is precisely directed and coupled onto the guideproximal end222P of the desiredlight guide222A. Thesignal processing electronics226B and thecontrol electronics226A monitor and keep track of this information.
• More particularly, with thesystem controller226 and/or thecontrol electronics226A controlling the speed of the scanning process, and with the offset between theprobe source beam270A and the individual guide beams224B being known, the time between the optimal alignment for coupling theprobe source beam270A and time when the individual guide beams224B will be at that location can be determined exactly. This allows thecatheter system200 to fully scan the face of theguide coupling housing250 and/or the guideproximal end222P of each of the light guides222A to determine the location of optimal coupling and leave time to correctly position the spot and fire thelight source224 accordingly. It is appreciated that this general concept can be applied for having thelight source224 fire and have the individual guide beams224B be precisely coupled onto the guideproximal end222P of each of the light guides222A in any suitable combination, order and/or pattern. This general concept is illustrated inFIGS. 3A through 3D.
• In particular,FIGS. 3A-3D are a schematic illustration representative of a timing scheme as the multiplexer and the multiplexer alignment system are scanning relative to the plurality of light guides, and a graphical representation of backscattered beam intensity as a function of scan position which is used to determine proper timing for firing of the light source. As shown, fourlight guides322A are organized into a linear array by aguide coupling housing350. The location of aprobe spot380P from the probe source beam is shown along with the projected location of aguide spot380G from the individual guide beam from the pulsed light source when it is fired. In particular, inFIG. 3A, theprobe spot380P from the probe source beam is initially approaching the guideproximal end322P of the thirdlight guide322A (labeled with the number “3”). As shown, the projectedguide spot380G for the guide beam is also shown as slightly lagging theprobe spot380P from the probe source beam in the scanning direction. Additionally, the graph to the right of the diagram shows the intensity signal of measured backscatter as a function of the position of the multiplexer. The multiplexer alignment system determines optimal coupling efficiency by identifying the local minimum in the curve.
• Next, inFIG. 3B, theprobe spot380P from the probe source beam is first starting to impinge on the guideproximal end322P of the thirdlight guide322A, with the projectedguide spot380G from the guide beam again slightly lagging behind along the scanning direction. Then, inFIG. 3C, theprobe spot380P from the probe source beam is precisely impinging on the guideproximal end322P of the thirdlight guide322A. As shown in the graph to the right, at such point the intensity signal is shown at a local minimum along the curve. Once theprobe spot380P from the probe source beam has passed this location and the guide spot from the primary beam comes into location, the light source is fired. Thus, based on the known offset between the probe source beam and the guide beam, and the known speed of the scan, it is understood that at this point it is the appropriate time to fire the light source so that the guide beam will be precisely coupled into the guide proximal end of the third light guide. Refinement of the timing of this process can achieve exact tuning for other characteristics of the laser pulse timing and characteristics and multiplexer dynamics. Such timing is shown inFIG. 3D.
• Returning now toFIG. 2, althoughFIG. 2 illustrates that the light guides222A are fixed in position relative to themultiplexer base258, in some alternative embodiments, it is appreciated that the light guides222A can be configured to move relative to thecoupling optics266 and theoptical element274 that are fixed in position. In such embodiments, theguide coupling housing250 itself would move, e.g., theguide coupling housing250 can be carried by a linear translation stage. Themultiplexer alignment system242 would need to monitor the position of this stage and determine parametric motion for the projected guide spot from thelight source224 while scanning and determining location for optimal coupling. The system controls the stage and steps it to align alight guide222A with theguide beam224B andcoupling optics266 when the determined position for optimal coupling was reached. While such an embodiment can be effective, it is further appreciated that additional protection and controls would be required to make it safe and reliable as theguide coupling housing250 moves relative to thecoupling optics266 of themultiplexer228 during use.
• Still alternatively, in another embodiment, the scanning process for each of themultiplexer alignment system242 and themultiplexer228 can be conducted independently from one another. In particular, in one non-exclusive alternative embodiment, thecatheter system200 can be configured such that themultiplexer alignment system242 conducts a full scanning and mapping of the faces of theguide coupling housing250 and/or the guide proximal ends222P of each of the light guides222A, without themultiplexer228 scanning as well substantially simultaneously. Thus, in such embodiment, themultiplexer alignment system242 would scan through everylight guide222A and find the X-Y location for eachlight guide222A that gives optimal coupling, and do this without firing the mainlight source224. It could go slowly and do a thorough X-Y scan across the face of theguide coupling housing250 and map the whole thing out. Such information would then be stored in the control electronics, with such information on locations being subsequently used for real-time firing of the primarylight source224. In this embodiment, themultiplexer alignment system242 could still utilize the secondlight source270 such as shown inFIG. 2. Alternatively, themultiplexer alignment system242 could also be configured to use the samelight source224 as is being used and manipulated by themultiplexer228.
• FIG. 4 is a simplified schematic illustration of a portion of another embodiment of thecatheter system400 including another embodiment of themultiplexer428 and themultiplexer alignment system442. As illustrated, the embodiment of thecatheter system400 illustrated inFIG. 7, including themultiplexer428 and themultiplexer alignment system442, is substantially similar in design and function to thecatheter system200 as illustrated and described in relation toFIG. 2. For example, as shown, thecatheter system400 again includes alight guide bundle422 including a plurality oflight guides422A retained within aguide coupling housing450; alight source424 that generates asource beam424A; asystem controller426 includingcontrol electronics426A andsignal processing electronics426B; themultiplexer428 and themultiplexer alignment system442.
• It is appreciated that thelight guide bundle422 can include any suitable number of light guides422A, which can be positioned and/or oriented relative to one another in any suitable manner, e.g., to best align the plurality oflight guides422A relative to themultiplexer428 and themultiplexer alignment system442. For example, in the embodiment illustrated inFIG. 4, thelight guide bundle422 again includes fourlight guides422A that are aligned in a generally linear arrangement relative to one another, with the guideproximal end422P of each of the light guides422A being retained within theguide coupling housing450. Thelight guide bundle422 and/or the light guides422A are substantially similar in design and function as described in detail herein above. Accordingly, such components will not be described in detail in relation to the embodiment illustrated inFIG. 4.
• As noted, themultiplexer428 and themultiplexer alignment system442 are substantially similar in design and function to what was described in detail herein above in relation toFIG. 2. In particular, themultiplexer428 again includes one or more of amultiplexer base458, amultiplexer stage460, astage mover462, aredirector464, and afirst beamsplitter468, which are used in conjunction with thesystem controller426, i.e. thecontrol electronics426A and/or thesignal processing electronics426B, and themultiplexer alignment system442. Additionally, themultiplexer alignment system442 again includes one or more of a secondlight source470 that generates aprobe source beam470A, thefirst beamsplitter468, asecond beamsplitter472, aphotodetector476 and anamplifier478, which are used in conjunction with thesystem controller426, i.e. thecontrol electronics426A and/or thesignal processing electronics426B, and themultiplexer428.
• However, in this embodiment, the relative positioning of certain components of themultiplexer428 and/or themultiplexer alignment system442 have been modified from the previous embodiment. Additionally, as shown, thecoupling optics266 of themultiplexer228 and theoptical element274 of themultiplexer alignment system242 have been replaced by couplingoptics482, which are configured to be included within and used by both themultiplexer428 and themultiplexer alignment system442.
• More specifically, as illustrated, each of thesource beam424A and theprobe source beam470A are directed toward and impinge upon thefirst beamsplitter468 before being directed toward thecoupling optics482. As shown inFIG. 4, thesource beam424A is transmitted through thefirst beamsplitter468, e.g., a dichroic beamsplitter, as individual guide beams424B that are directed through thecoupling optics482 to be directed and focused to scan across the face of theguide coupling housing450 and/or the guideproximal end422P of each of the light guides422A. Similarly, as shown, theprobe source beam470A is redirected by thefirst beamsplitter468 so that theprobe source beam470A is also directed through thecoupling optics482 to be directed and focused to scan across the face of theguide coupling housing450 and/or the guideproximal end422P of each of the light guides422A. With such design, i.e. with use ofcoupling optics482 that is used for both themultiplexer428 and themultiplexer alignment system442, the overall design can have a simplified and more compact layout. The guide beams424B and theprobe source beam470A are focused down after thecoupling optics482 thereby improving damage threshold for thecoupling optics482. Additionally, such design also moves the focal part of the guide beams424B and theprobe source beam470A further out from themultiplexer stage460 which eases the configuration for the connection of theguide coupling housing450 to the system console123 (illustrated inFIG. 1).
• Similar to the previous embodiment, during the scanning process, at least a portion of the light in the focused spot from theprobe source beam470A scatters off the faces of theguide coupling housing450 and the individual light guides422A, and is directed back toward thecoupling optics482 and thefirst beamsplitter468 as abackscattered energy beam470B. After being focused and collimated by thecoupling optics482, thebackscattered energy beam470B is reflected off of and redirected by thefirst beamsplitter468 toward thesecond beamsplitter472, e.g., a 10/90 beamsplitter or another suitable type of beamsplitter (i.e. with different levels of transmittance and reflectance of the incident beam). Thesecond beamsplitter472 subsequently reflects a portion, e.g., most, of the light returned as thebackscattered energy beam470B onto thephotodetector476.
• Additionally, in some embodiments, thephotodetector476 then generates a signal that is based on the portion of the visible light scattered from the faces of theguide coupling housing450 and the individual light guides422A, i.e. the portion of thebackscattered energy beam470B, which has been collected by thephotodetector476. As shown inFIG. 4, the signal from thephotodetector476 is then directed toward theamplifier478 where the signal from thephotodetector476 is amplified. The amplified signal is thus utilized, e.g., within thesignal processing electronics426B, to determine the intensity of thebackscattered energy beam470B. It is understood that in this, and various other embodiments, thephotodetector476 can include additional focusing or collecting optics.
• Further, as with the previous embodiment, when the intensity of thebackscattered energy beam470B is determined to be at a local minimum, i.e. by thesignal processing electronics426B, then it is determined that it is an appropriate time to fire thelight source424 so that aguide beam424B is precisely directed and coupled onto the guideproximal end422P of the desiredlight guide422A. Thesignal processing electronics426B and thecontrol electronics426A monitor and keep track of this information. More particularly, with thesystem controller426 and/or thecontrol electronics426A controlling the speed of the scanning process, and with the offset between theprobe source beam470A and the individual guide beams424B being known, the time between the optimal alignment for coupling theprobe source beam470A and time when the individual guide beams424B will be at that location can be determined exactly. This allows thecatheter system400 to fully scan the face of theguide coupling housing450 and/or the guideproximal end422P of each of the light guides422A to determine the location of optimal coupling and leave time to correctly position the spot and fire thelight source424 accordingly. It is appreciated that this general concept can be applied for having thelight source424 fire and have the individual guide beams424B be precisely coupled onto the guideproximal end422P of each of the light guides422A in any suitable combination, order and/or pattern.
• Moreover, althoughFIG. 4 illustrates that the light guides422A are fixed in position relative to themultiplexer base458, in some alternative embodiments, it is appreciated that the light guides422A can be configured to move relative to thecoupling optics482 that are fixed in position. In such embodiments, theguide coupling housing450 itself would move, e.g., theguide coupling housing450 can be carried by a linear translation stage. Themultiplexer alignment system442 would need to monitor the position of this stage and determine parametric motion for the projected guide spot from thelight source424 while scanning and determining location for optimal coupling. The system controls the stage and steps it to align alight guide422A with theguide beam424B andcoupling optics482 when the determined position for optimal coupling was reached.
• FIG. 5 is a simplified schematic illustration of a portion of still another embodiment of thecatheter system500 including still another embodiment of themultiplexer528 and themultiplexer alignment system542. In particular, as shown inFIG. 5, thecatheter system500 can include one or more of alight guide bundle522 including a plurality oflight guides522A retained within aguide coupling housing550; alight source524 that generates asource beam524A; asystem controller526 includingcontrol electronics526A andsignal processing electronics526B; themultiplexer528 and themultiplexer alignment system542.
• It is appreciated that thelight guide bundle522 can include any suitable number of light guides522A, which can be positioned and/or oriented relative to one another in any suitable manner, e.g., to best align the plurality oflight guides522A relative to themultiplexer528 and themultiplexer alignment system542. For example, in the embodiment illustrated inFIG. 5, thelight guide bundle522 again includes fourlight guides522A that are aligned in a generally linear arrangement relative to one another, with the guideproximal end522P of each of the light guides522A being retained within theguide coupling housing550. Thelight guide bundle522 and/or the light guides522A are substantially similar in design and function as described in detail herein above. Accordingly, such components will not be described in detail in relation to the embodiment illustrated inFIG. 5.
• As with the previous embodiments, themultiplexer528 is configured to receive light energy in the form of thesource beam524A, e.g., a pulsed source beam, from thelight source524 and direct the light energy in the form of individual guide beams524B onto the guideproximal end522P of each of the plurality of the light guides522A in any desired combination, order, sequence and/or pattern.
• The design of themultiplexer528 can be varied depending on the requirements of thecatheter system500, the relative positioning of the light guides522A, and/or to suit the desires of the user or operator of thecatheter system500. In the embodiment illustrated inFIG. 5, themultiplexer528 includes one or more of a (fixed)redirector564, afirst beamsplitter568, a firstmovable redirector584, a secondmovable redirector586, andcoupling optics582, which are used in conjunction with thesystem controller526, i.e. thecontrol electronics526A and/or thesignal processing electronics526B, and themultiplexer alignment system542 as described in detail herein. Alternatively, themultiplexer528 can include more components or fewer components than those specifically illustrated inFIG. 5.
• Additionally, as with the previous embodiments, themultiplexer alignment system542 is configured to probe the face of the light guide bundle522 (i.e. the face of the guide coupling housing550) and/or the guideproximal end522P of each of the light guides522A in thelight guide bundle522 as a means to improve optical coupling between the guide beams524B and the guideproximal end522P of each of the light guides522A.
• The design of themultiplexer alignment system542 can be varied depending on the requirements of thecatheter system500, the relative positioning of the light guides522A, and/or to suit the desires of the user or operator of thecatheter system500. In the embodiment illustrated inFIG. 5, themultiplexer alignment system542 includes one or more of the secondlight source570, thefirst beamsplitter568, asecond beamsplitter572, the firstmovable redirector584, the secondmovable redirector586, thecoupling optics582, aphotodetector576 and anamplifier578, which are used in conjunction with thesystem controller526, i.e. thecontrol electronics526A and/or thesignal processing electronics526B, and themultiplexer528. As described in detail herein, the secondlight source570 provides light energy in the form of theprobe source beam570A that is directed to scan across the guideproximal end522P of each of the light guides522A during a mapping process. Alternatively, themultiplexer alignment system542 can include more components or fewer components than those specifically illustrated inFIG. 5.
• As above, in various embodiments, themultiplexer528 and themultiplexer alignment system542 are configured to operate substantially simultaneously, with theprobe source beam570A from the secondlight source570 slightly leading the guide beams524B from thelight source524, as both theprobe source beam570A and the individual guide beams524B are scanning across the face of theguide coupling housing550. Alternatively, in other embodiments, themultiplexer alignment system542 can be configured to fully map out the face of theguide coupling housing550 with theprobe source beam570A from the secondlight source570 prior to any use of thelight source524 and themultiplexer528 that are configured to direct and focus individual guide beams524B onto the guideproximal end522P of each of the light guides522A in any desired sequence, order or pattern. The general operation of each of themultiplexer528 and themultiplexer alignment system542 in the embodiments shown inFIG. 5 will now be described in greater detail.
• During use of themultiplexer528, thesource beam524A from thelight source524 is initially directed toward and impinges on theredirector564, which is configured to redirect thesource beam524A, e.g., by approximately 90 degrees or another suitable amount, toward thefirst beamsplitter568, e.g., a dichroic beamsplitter. Subsequently, based on the design of thefirst beamsplitter568, thesource beam524A is transmitted through thefirst beamsplitter568 and toward the firstmovable redirector584. As shown, the firstmovable redirector584 is configured to redirect thesource beam524A toward the secondmovable redirector586. In this embodiment, the firstmovable redirector584 is selectively rotatable about arotational axis584X, i.e. by afirst redirector mover584A, to adjust the angle of thesource beam524A as thesource beam524A is directed toward the secondmovable redirector586. Thesource beam524A is then redirected by the secondmovable redirector586 and directed toward thecoupling optics582 as aguide beam524B that will be coupled by thecoupling optics582 onto the guideproximal end522P of eachlight guide522A as desired. In this embodiment, the secondmovable redirector586 is selectively rotatable about arotational axis586X, i.e. by asecond redirector mover586A, to adjust the angle of theguide beam524B as theguide beam524B is directed toward thecoupling optics582. As used herein, thecoupling optics582 can alternatively include a simple lens, a compound lends or an f-theta lens.
• It is appreciated that the firstmovable redirector584 and the secondmovable redirector586, and thecorresponding redirector movers584A,586A, can have any suitable design for purposes of redirecting thesource beam524A and/or the guide beams524B in a desired manner. For example, in one embodiment, each of the firstmovable redirector584 and the secondmovable redirector586 can be provided in the form of a galvanometer, i.e. a galvanometer mirror scanner, that includes a mirror (or other reflective surface) that is rotated about therotational axis584X,586X using theredirector mover584A,586A, respectively. Alternatively, themovable redirectors584,586, can include one or more multi-axis scanners. Themovers584A,586A are utilized to rotate themovable redirectors584,586, respectively, in order to steer theguide beam524B into thecoupling optics582, i.e. at a desired incident angle, so that theguide beam524B can be selectively focused by thecoupling optics582 onto any of the light guides522A within thelight guide bundle522. In particular, as themovable redirectors584,586 are rotated, themovable redirectors584,586 steer theguide beam524B into thecoupling optics582, e.g., a focusing lens, at different angles. This results in scanning of theguide beam524B in a linear manner, translating the focal point into different light guides522A mounted within thelight guide bundle522. Thus, by changing the angle of themovable redirectors584,586, theguide beam524B can be selectively steered onto the guideproximal end522P of any of the light guides522A in thelight guide bundle522. In non-exclusive alternative embodiments, themovable redirectors584,586 can include mirrors attached to optomechanical scanners, galvanometers or other multi-axis beam steering devices that are used to direct thesource beam524A and/or the guide beams524B as desired through thecoupling optics582 so the guide beams524B are coupled into selected light guides522A in any desired manner.
• Additionally, during use of themultiplexer alignment system542, as shown inFIG. 5, theprobe source beam570A from thesecond energy source570 is initially directed toward thesecond beamsplitter572, from where at least a portion of theprobe source beam570A is directed onward toward thefirst beamsplitter568. Subsequently, based on the design of thefirst beamsplitter568, theprobe source beam570A is redirected by thefirst beamsplitter568 and toward the firstmovable redirector584. From here, theprobe source beam570A follows the same path as described above for thesource beam524A and/or the guide beams524B as they are ultimately directed and focused onto the light guides522A. In particular, as illustrated, the firstmovable redirector584 is configured to redirect theprobe source beam570A toward the secondmovable redirector586, which then redirects theprobe source beam570A toward thecoupling optics582. Thecoupling optics582 then direct and focus theprobe source beam570A toward theguide coupling housing550. By adjusting the angles of each of the firstmovable redirector584 and the secondmovable redirector586 as described above, theprobe source beam570A can then be focused by thecoupling optics582 to scan across the face of theguide coupling housing550 and/or the guideproximal end522P of each of the light guides522A in thelight guide bundle522.
• As noted, in certain embodiments, as shown inFIG. 5, thecatheter system500 is controlled such that theprobe source beam570A is slightly offset from the individual guide beams524B as they are scanned across the face of theguide coupling housing550. More particularly, in such embodiments, themovable redirectors584,586 and thecoupling optics582 can be configured and/or positioned such that theprobe source beam570A slightly leads or is slightly ahead of the individual guide beams524B during the scanning process. Stated in another manner, themovable redirectors584,586 and thecoupling optics582 are aligned such that the spot from theguide beam524B is formed a controlled distance lagging the spot from theprobe source beam570A.
• Further, similar to the previous embodiments, during the scanning process, at least a portion of the light in the focused spot from theprobe source beam570A scatters off the faces of theguide coupling housing550 and the individual light guides522A, and is directed back toward thecoupling optics582, the secondmovable redirector586, the firstmovable redirector584, and thefirst beamsplitter568 as abackscattered energy beam570B. After being focused and collimated by thecoupling optics582, and redirected by the secondmovable redirector586 and the firstmovable redirector584, thebackscattered energy beam570B is reflected off of and redirected by thefirst beamsplitter568 toward thesecond beamsplitter572, e.g., a 10/90 beamsplitter or another suitable type of beamsplitter (i.e. with different levels of transmittance and reflectance of the incident beam). Thesecond beamsplitter572 subsequently reflects a portion, e.g., most, of the light returned as thebackscattered energy beam570B onto thephotodetector576.
• Additionally, in some embodiments, thephotodetector576 then generates a signal that is based on the portion of the visible light scattered from the faces of theguide coupling housing550 and the individual light guides522A, i.e. the portion of thebackscattered energy beam570B, which has been collected by thephotodetector576. As shown inFIG. 5, the signal from thephotodetector576 is then directed toward theamplifier578 where the signal from thephotodetector576 is amplified. The amplified signal is thus utilized, e.g., within thesignal processing electronics526B, to determine the intensity of the backscattered energy beam5708.
• Further, as with the previous embodiments, when the intensity of thebackscattered energy beam570B is determined to be at a local minimum, i.e. by thesignal processing electronics526B, then it is determined that it is an appropriate time to fire thelight source524 so that aguide beam524B is precisely directed and coupled onto the guideproximal end522P of the desiredlight guide522A. Thesignal processing electronics526B and thecontrol electronics526A monitor and keep track of this information. More particularly, with thesystem controller526 and/or thecontrol electronics526A controlling the speed of the scanning process, and with the offset between theprobe source beam570A and the individual guide beams524B being known, the time between the optimal alignment for coupling theprobe source beam570A and time when the individual guide beams524B will be at that location can be determined exactly. This allows thecatheter system500 to fully scan the face of theguide coupling housing550 and/or the guideproximal end522P of each of the light guides522A to determine the location of optimal coupling and leave time to correctly position the spot and fire thelight source524 accordingly. It is appreciated that this general concept can be applied for having thelight source524 fire and have the individual guide beams524B be precisely coupled onto the guideproximal end522P of each of the light guides522A in any suitable combination, order and/or pattern.
• FIG. 6 is a simplified schematic illustration of a portion of yet another embodiment of thecatheter system600 including yet another embodiment of themultiplexer628 and themultiplexer alignment system642. In particular, as shown inFIG. 6, thecatheter system600 can include one or more of alight guide bundle622 including a plurality oflight guides622A retained within aguide coupling housing650; alight source624 that generates asource beam624A; asystem controller626 includingcontrol electronics626A andsignal processing electronics626B; themultiplexer628 and themultiplexer alignment system642.
• It is appreciated that thelight guide bundle622 can include any suitable number of light guides622A, which can be positioned and/or oriented relative to one another in any suitable manner, e.g., to best align the plurality oflight guides622A relative to themultiplexer628 and themultiplexer alignment system642. For example, in the embodiment illustrated inFIG. 6, thelight guide bundle622 includes sixlight guides622A that are aligned in a generally circular arrangement relative to one another, with the guideproximal end622P of each of the light guides622A being retained withinguide coupling slots656 within theguide coupling housing650, i.e. a generally cylindrical-shapedguide coupling housing650. Thelight guide bundle622 and/or the light guides622A are substantially similar in design and function as described in detail herein above. Accordingly, such components will not be described in detail in relation to the embodiment illustrated inFIG. 6.
• As with the previous embodiments, themultiplexer628 is configured to receive light energy in the form of thesource beam624A, e.g., a pulsed source beam, from thelight source624 and direct the light energy in the form of individual guide beams624B onto the guideproximal end622P of each of the plurality of the light guides622A in any desired combination, order, sequence and/or pattern.
• The design of themultiplexer628 can be varied depending on the requirements of thecatheter system600, the relative positioning of the light guides622A, and/or to suit the desires of the user or operator of thecatheter system600. In the embodiment illustrated inFIG. 6, themultiplexer628 includes one or more of aredirector664, afirst beamsplitter668, amultiplexer stage660, astage mover662, abeam path adjuster688, andcoupling optics682, which are used in conjunction with thesystem controller626, i.e. thecontrol electronics626A and/or thesignal processing electronics626B, and themultiplexer alignment system642 as described in detail herein. Alternatively, themultiplexer628 can include more components or fewer components than those specifically illustrated inFIG. 6.
• Additionally, as with the previous embodiments, themultiplexer alignment system642 is configured to probe the face of the light guide bundle622 (i.e. the face of the guide coupling housing650) and/or the guideproximal end622P of each of the light guides622A in thelight guide bundle622 as a means to improve optical coupling between the guide beams624B and the guideproximal end622P of each of the light guides622A.
• The design of themultiplexer alignment system642 can be varied depending on the requirements of thecatheter system600, the relative positioning of the light guides622A, and/or to suit the desires of the user or operator of thecatheter system600. In the embodiment illustrated inFIG. 6, themultiplexer alignment system642 includes one or more of the secondlight source670, thefirst beamsplitter668, asecond beamsplitter672, thebeam path adjuster688, thecoupling optics682, aphotodetector676 and anamplifier678, which are used in conjunction with thesystem controller626, i.e. thecontrol electronics626A and/or thesignal processing electronics626B, and themultiplexer628. As described in detail herein, the secondlight source670 provides light energy in the form of theprobe source beam670A that is directed to scan across the guideproximal end622P of each of the light guides622A during a mapping process. Alternatively, themultiplexer alignment system642 can include more components or fewer components than those specifically illustrated inFIG. 6.
• As above, in various embodiments, themultiplexer628 and themultiplexer alignment system642 are configured to operate substantially simultaneously, with theprobe source beam670A from the secondlight source670 slightly leading the guide beams624B from thelight source624, as both theprobe source beam670A and the individual guide beams624B are scanning across the face of theguide coupling housing650. Alternatively, in other embodiments, themultiplexer alignment system642 can be configured to fully map out the face of theguide coupling housing650 with theprobe source beam670A from the secondlight source670 prior to any use of thelight source624 and themultiplexer628 that are configured to direct and focus individual guide beams624B onto the guideproximal end622P of each of the light guides622A in any desired sequence, order or pattern. The general operation of each of themultiplexer628 and themultiplexer alignment system642 in the embodiments shown inFIG. 6 will now be described in greater detail.
• During use of themultiplexer628, thesource beam624A from thelight source624 is initially directed toward and impinges on theredirector664, which is configured to redirect thesource beam624A, e.g., by approximately 90 degrees or another suitable amount, toward thefirst beamsplitter668, e.g., a dichroic beamsplitter. Subsequently, based on the design of thefirst beamsplitter668, thesource beam624A is transmitted through thefirst beamsplitter668 and toward thebeam path adjuster688.
• As shown, thebeam path adjuster688 and thecoupling optics682 are mounted on and/or retained by themultiplexer stage660. Additionally, as shown in the embodiment illustrated inFIG. 6, thestage mover662 is configured to move themultiplexer stage660 in a rotational manner. More particularly, in this embodiment, themultiplexer stage660 and/or thestage mover662 requires a single rotational degree of freedom. Additionally, as shown, themultiplexer stage660 and/or thebeam path adjuster688 is aligned with the beam path of thesource beam624A from theredirector664 on arotational axis688X. As such, themultiplexer stage660 is configured to be rotated by thestage mover662 about therotational axis688X.
• During use of thecatheter system600, thesource beam624A is initially directed toward themultiplexer stage660 along therotational axis688X. Subsequently, thebeam path adjuster688 is configured to deviate thesource beam624A a fixed distance laterally, i.e. off therotational axis688X, such that thesource beam624A is directed in a direction that is substantially parallel to and spaced apart from therotational axis688X. More specifically, thebeam path adjuster688 deviates thesource beam624A to coincide with the radius of the circular pattern of the light guides622A in theguide coupling housing650. As themultiplexer stage660 is rotated, thesource beam624A that is directed through thebeam path adjuster688 traces out a circular path.
• It is appreciated that thebeam path adjuster688 can have any suitable design. For example, in certain non-exclusive alternative embodiments, thebeam path adjuster688 can be provided in the form of an anamorphic prism pair, a pair of wedge prisms, or a pair of close-spaced right angle mirrors or prisms. Alternatively, thebeam path adjuster688 can include another suitable configuration of optics in order to achieve the desired lateral beam offset.
• Additionally, as noted, thecoupling optics682 are also mounted on and/or retained by themultiplexer stage660. As with the previous embodiments, thecoupling optics682 are configured to focus the individual guide beams624B to each of the light guides622A in thelight guide bundle622 retained, in part, within theguide coupling housing650 for optimal coupling.
• Further, during use of themultiplexer alignment system642, as shown inFIG. 6, theprobe source beam670A from thesecond energy source670 is initially directed toward thesecond beamsplitter672, from where at least a portion of theprobe source beam670A is directed onward toward thefirst beamsplitter668. Subsequently, based on the design of thefirst beamsplitter668, theprobe source beam670A is redirected by thefirst beamsplitter668 and toward thebeam path adjuster688. From here, theprobe source beam670A follows the same path as described above for thesource beam624A and/or the guide beams624B as they are ultimately directed and focused onto the light guides622A. In particular, as illustrated, thebeam path adjuster688 is configured to deviate theprobe source beam670A a fixed distance laterally, i.e. off therotational axis688X, such that theprobe source beam670A is directed in a direction that is substantially parallel to and spaced apart from therotational axis688X toward thecoupling optics682. Thecoupling optics682 then direct and focus theprobe source beam670A toward theguide coupling housing650. By rotating themultiplexer stage660 with thestage mover662 in a rotational manner as described above, theprobe source beam670A can then be focused by thecoupling optics682 to scan circularly about the face of theguide coupling housing650 and/or the guideproximal end622P of each of the light guides622A in thelight guide bundle622.
• In this embodiment, thestage mover662 can have any suitable design for purposes of moving themultiplexer stage660 in a rotational manner about therotational axis688X. More particularly, thestage mover662 can be any suitable type of rotational mechanism. Additionally, in some embodiments, thestage mover662 can be electronically controlled, e.g., using stepper motors or a piezo-actuated rotational stage, to line the beam path of theguide beam624B sequentially with each individuallight guide622A that is retained, in part, within theguide coupling housing650. Alternatively, in other embodiments, thestage mover662 and/or themultiplexer stage660 can be equipped with mechanical stops so that thecoupling optics682 can be precisely aligned with the position of each of the light guides622A.
• As noted, in certain embodiments, as shown inFIG. 6, thecatheter system600 is controlled such that theprobe source beam670A is slightly offset from the individual guide beams624B as they are scanned about the face of theguide coupling housing650. More particularly, in such embodiments, thebeam path adjuster688 and thecoupling optics682 can be configured and/or positioned such that theprobe source beam670A slightly leads or is slightly ahead of the individual guide beams624B during the scanning process. Stated in another manner, thebeam path adjuster688 and thecoupling optics682 are aligned such that the spot from theguide beam624B is formed a controlled distance lagging the spot from theprobe source beam670A.
• Further, similar to the previous embodiments, during the scanning process, at least a portion of the light in the focused spot from theprobe source beam670A scatters off the faces of theguide coupling housing650 and the individual light guides622A, and is directed back toward thecoupling optics682, thebeam path adjuster688, and thefirst beamsplitter668 as abackscattered energy beam670B. After being focused and collimated by thecoupling optics682, and redirected by thebeam path adjuster688, thebackscattered energy beam670B is reflected off of and redirected by thefirst beamsplitter668 toward thesecond beamsplitter672, e.g., a 10/90 beamsplitter or another suitable type of beamsplitter (i.e. with different levels of transmittance and reflectance of the incident beam). Thesecond beamsplitter672 subsequently reflects a portion, e.g., most, of the light returned as thebackscattered energy beam670B onto thephotodetector676.
• Additionally, in some embodiments, thephotodetector676 then generates a signal that is based on the portion of the visible light scattered from the faces of theguide coupling housing650 and the individual light guides622A, i.e. the portion of thebackscattered energy beam670B, which has been collected by thephotodetector676. As shown inFIG. 6, the signal from thephotodetector676 is then directed toward theamplifier678 where the signal from thephotodetector676 is amplified. The amplified signal is thus utilized, e.g., within thesignal processing electronics626B, to determine the intensity of the backscattered energy beam6708.
• Further, as with the previous embodiments, when the intensity of thebackscattered energy beam670B is determined to be at a local minimum, i.e. by thesignal processing electronics626B, then it is determined that it is an appropriate time to fire thelight source624 so that aguide beam624B is precisely directed and coupled onto the guideproximal end622P of the desiredlight guide622A. Thesignal processing electronics626B and thecontrol electronics626A monitor and keep track of this information. More particularly, with thesystem controller626 and/or thecontrol electronics626A controlling the speed of the scanning process, and with the offset between theprobe source beam670A and the individual guide beams624B being known, the time between the optimal alignment for coupling theprobe source beam670A and time when the individual guide beams624B will be at that location can be determined exactly. This allows thecatheter system600 to fully scan the face of theguide coupling housing650 and/or the guideproximal end622P of each of the light guides622A to determine the location of optimal coupling and leave time to correctly position the spot and fire thelight source624 accordingly. It is appreciated that this general concept can be applied for having thelight source624 fire and have the individual guide beams624B be precisely coupled onto the guideproximal end622P of each of the light guides622A in any suitable combination, order and/or pattern.
• Alternatively, althoughFIG. 6 illustrates that the light guides622A are fixed in position relative to themultiplexer stage660, in some embodiments, it is appreciated that the light guides622A can be configured to move, e.g., rotate relative tocoupling optics682 that are fixed in position. In such embodiments, theguide coupling housing650 itself would move, e.g., theguide coupling housing650 can be rotated about therotational axis688X, and thesystem controller626 can control the rotational stage to move in a stepped manner so that the light guides622A are each aligned, in a desired pattern, with the coupling optics and the guide beams624B. Themultiplexer alignment system642 would need to monitor the position of this stage and determine motion for the projected guide spot from thelight source624 while scanning and determining location for optimal coupling. The system controls the stage and steps it to align alight guide622A with theguide beam624B andcoupling optics682 when the determined position for optimal coupling was reached. In such embodiment, theguide coupling housing650 would not be continuously rotated, but would be rotated a fixed number of degrees and then counter-rotated to avoid the winding of the light guides622A.
• FIG. 7 is a simplified schematic illustration of a portion of still yet another embodiment of thecatheter system700 including still yet another embodiment of themultiplexer728 and themultiplexer alignment system742. As illustrated, the embodiment of thecatheter system700 illustrated inFIG. 7, including themultiplexer728 and themultiplexer alignment system742 is substantially similar to thecatheter system200 as illustrated and described in relation toFIG. 2. For example, as shown, thecatheter system700 again includes alight guide bundle722 including a plurality oflight guides722A retained within aguide coupling housing750; alight source724 that generates asource beam724A; asystem controller726 includingcontrol electronics726A andsignal processing electronics726B; themultiplexer728 and themultiplexer alignment system742.
• It is appreciated that thelight guide bundle722 can include any suitable number of light guides722A, which can be positioned and/or oriented relative to one another in any suitable manner, e.g., to best align the plurality oflight guides722A relative to themultiplexer728 and themultiplexer alignment system742. For example, in the embodiment illustrated inFIG. 4, thelight guide bundle722 again includes fourlight guides722A that are aligned in a generally linear arrangement relative to one another, with the guideproximal end722P of each of the light guides722A being retained within theguide coupling housing750. Thelight guide bundle722 and/or the light guides722A are substantially similar in design and function as described in detail herein above. Accordingly, such components will not be described in detail in relation to the embodiment illustrated inFIG. 7.
• As noted, themultiplexer728 and themultiplexer alignment system742 are substantially similar in design and function to what was described in detail herein above in relation toFIG. 2. In particular, themultiplexer728 again includes one or more of amultiplexer base758, amultiplexer stage760, astage mover762, aredirector764,coupling optics766, and afirst beamsplitter768, which are used in conjunction with thesystem controller726, i.e. thecontrol electronics726A and/or thesignal processing electronics726B, and themultiplexer alignment system742. Additionally, themultiplexer alignment system742 again includes one or more of a secondlight source770 that generates aprobe source beam770A, thefirst beamsplitter768, asecond beamsplitter772, anoptical element774, aphotodetector776 and anamplifier778, which are used in conjunction with thesystem controller726, i.e. thecontrol electronics726A and/or thesignal processing electronics726B, and themultiplexer728.
• However, in this embodiment, the mode of operation of thecatheter system700 is somewhat different in that the scanning process for each of themultiplexer alignment system742 and themultiplexer728 are conducted independently from one another. In particular, in such embodiment, thecatheter system700 is configured such that themultiplexer alignment system742 conducts a full scanning and mapping of the faces of theguide coupling housing750 and/or the guide proximal ends722P of each of the light guides722A with theprobe source beam770A from the secondlight source770 which is scattered back at least partially as thebackscattered energy beam770B, without themultiplexer728 scanning with individual guide beams724B as well substantially simultaneously. Thus, in such embodiment, themultiplexer alignment system742 would scan through everylight guide722A and find the X-Y location for eachlight guide722A that gives optimal coupling, and do this without firing the mainlight source724. It could go slowly and do a thorough X-Y scan across the face of theguide coupling housing750 and map the whole thing out. Such information would then be stored in thecontrol electronics726A, with such information on locations being subsequently used for real-time firing of the primarylight source724. In this embodiment, themultiplexer alignment system742 could still utilize the secondlight source770 such as shown inFIG. 7. Alternatively, themultiplexer alignment system742 could also be configured to use the samelight source724 as is being used and manipulated by themultiplexer728.
• In application of this alternative embodiment, thecatheter system700 could be used following the steps of: 1) user inserts guidecoupling housing750 into the system console123 (illustrated inFIG. 1), 2) thecatheter system700 locks theguide coupling housing750 in place and switches to standby mode, 3) themultiplexer alignment system742 scans across the face of theguide coupling housing750 following some X-Y pattern (zig-zag, etc.) mapping out the location for optimal coupling for eachlight guide722A, 4) thesystem controller726 and/or thecontrol electronics726A stores all of those locations and switches over to ready mode, 5) the user actuates the catheter102 (illustrated inFIG. 1) and themultiplexer728 scans across face of theguide coupling housing750 and stops at each optimal X-Y location and fires thelight source724.
• Although the embodiment described inFIG. 7 is shown as being employed within an embodiment that is substantially similar to that illustrated and described in relation toFIG. 2, it is appreciated that such alternative mode of operation of the multiplexer and the multiplexer alignment system can be utilized with any of the embodiments illustrated and described herein.
• As described in detail herein, in various embodiments, the multiplexer and the multiplexer alignment system can be utilized to solve one or more of the problems that exist in more traditional catheter systems. For example:
• • 1) The multiplexer and the multiplexer alignment system reduce optical coupling dependence on the precision and mechanical tolerance stack-ups of assemblies and true alignment for the light guides, the guide coupling housing, and associated connections, thereby making it possible to use low-cost, low-precision components on the single-use device and improve cost of goods sold.
  • 2) The multiplexer and the multiplexer alignment system reduce the multiplexer performance dependence on the accuracy of the positioning mechanism in the multiplexer and associated quality and precision of its optical and mechanical components thereby improving speed and performance of the multiplexer and the overall catheter system.
• It should be noted that, as used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the content and/or context clearly dictates otherwise. It should also be noted that the term “or” is generally employed in its sense including “and/or” unless the content or context clearly dictates otherwise.
• It should also be noted that, as used in this specification and the appended claims, the phrase “configured” describes a system, apparatus, or other structure that is constructed or configured to perform a particular task or adopt a particular configuration. The phrase “configured” can be used interchangeably with other similar phrases such as arranged and configured, constructed and arranged, constructed, manufactured and arranged, and the like.
• The headings used herein are provided for consistency with suggestions under 37 CFR 1.77 or otherwise to provide organizational cues. These headings shall not be viewed to limit or characterize the invention(s) set out in any claims that may issue from this disclosure. As an example, a description of a technology in the “Background” is not an admission that technology is prior art to any invention(s) in this disclosure. Neither is the “Summary” or “Abstract” to be considered as a characterization of the invention(s) set forth in issued claims.
• The embodiments described herein are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art can appreciate and understand the principles and practices. As such, aspects have been described with reference to various specific and preferred embodiments and techniques. However, it should be understood that many variations and modifications may be made while remaining within the spirit and scope herein.
• It is understood that although a number of different embodiments of the catheter systems have been illustrated and described herein, one or more features of any one embodiment can be combined with one or more features of one or more of the other embodiments, provided that such combination satisfies the intent of the present invention.
• While a number of exemplary aspects and embodiments of the catheter systems have been discussed above, those of skill in the art will recognize certain modifications, permutations, additions and sub-combinations thereof. It is therefore intended that the following appended claims and claims hereafter introduced are interpreted to include all such modifications, permutations, additions and sub-combinations as are within their true spirit and scope, and no limitations are intended to the details of construction or design herein shown.

Claims (22)

What is claimed is:

1. A catheter system for treating a treatment site within or adjacent to a vessel wall or heart valve, the catheter system comprising:

a first light source that generates light energy;

a plurality of light guides that are each configured to alternatingly receive light energy from the first light source, each light guide having a guide proximal end;

a multiplexer that receives the light energy from the first light source, the multiplexer alternatingly directing the light energy from the first light source to each of the plurality of light guides; and

a multiplexer alignment system that is operatively coupled to the multiplexer, the multiplexer alignment system including a second light source that generates a probe source beam that scans the guide proximal end of each of the plurality of light guides.

2. The catheter system ofclaim 1 wherein the probe source beam scanning the guide proximal end of each of the plurality of light guides produces a backscattered energy beam that is scattered off of the guide proximal end of each of the plurality of light guides; and further comprising a system controller that analyzes the backscattered energy beam to determine optical coupling between the guide beams and the plurality of light guides.

3. The catheter system ofclaim 2 wherein the system controller is configured to control operation of the first light source to generate pulses of light energy.

4. The catheter system ofclaim 1 wherein the plurality of light guides are retained at least partially within a guide coupling housing, and the probe source beam is configured to scan a face of the guide coupling housing.

5. The catheter system ofclaim 4 wherein the guide proximal end of each of the plurality of light guides is retained within the guide coupling housing.

6. The catheter system ofclaim 1 wherein the multiplexer alignment system is operatively coupled to the multiplexer so that the probe source beam scans the guide proximal end of each of the plurality of light guides at a predetermined time prior to the individual guide beams scanning the guide proximal end of each of the plurality of light guides.

7. The catheter system ofclaim 1 wherein the multiplexer alignment system includes coupling optics that are configured to focus the probe source beam to scan the guide proximal end of each of the plurality of light guides.

8. The catheter system ofclaim 7 wherein the multiplexer is configured to utilize the coupling optics to focus each of the individual guide beams to one of the plurality of light guides.

9. The catheter system ofclaim 1 further comprising a first beamsplitter that receives a source beam from the first light source and the probe source beam from the second light source, the first beamsplitter being configured to direct each of the source beam and the probe source beam toward the guide proximal end of each of the plurality of light guides.

10. The catheter system ofclaim 9 wherein the first beamsplitter includes a dichroic beamsplitter.

11. The catheter system ofclaim 9 wherein the first beamsplitter is configured to transmit one of the source beam and the probe source beam and to reflect the other of the source beam and the probe source beam.

12. The catheter system ofclaim 9 further comprising a second beamsplitter and a photodetector, the second beamsplitter being configured to (i) receive the backscattered energy beam, and (ii) direct at least a portion of the backscattered energy beam toward the photodetector.

13. The catheter system ofclaim 12 wherein the photodetector generates a signal based at least in part on the at least a portion of the backscattered energy beam that is directed toward the photodetector.

14. The catheter system ofclaim 13 wherein the signal from the photodetector is amplified with an amplifier to provide an amplified signal that is directed to signal processing electronics to determine an intensity of light energy contained within the backscattered energy beam.

15. The catheter system ofclaim 14 wherein the intensity of light energy contained within the backscattered energy beam is evaluated to determine optimal optical coupling between the guide beams and the plurality of light guides.

16. The catheter system ofclaim 1 wherein the multiplexer includes a multiplexer base, a multiplexer stage, and a stage mover that moves the multiplexer stage in a linear degree of freedom relative to the multiplexer base.

17. The catheter system ofclaim 1 wherein the multiplexer includes a multiplexer stage and a stage mover that moves the multiplexer stage relative to each of the plurality of light guides.

18. The catheter system ofclaim 17 wherein the stage mover moves the multiplexer stage rotationally about a rotational axis.

19. The catheter system ofclaim 1 wherein the first light source includes a laser.

20. The catheter system ofclaim 1 wherein the second light source includes a laser.

21. The catheter system ofclaim 1 wherein the multiplexer includes a first movable redirector and a second movable redirector, at least one of the redirectors including a multi-directional scanner with an f-theta lens.

22. A method for treating a treatment site within or adjacent to a vessel wall or a heart valve, the method including utilizing the catheter system ofclaim 1.

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