US20150305612A1 - Apparatuses and methods for registering a real-time image feed from an imaging device to a steerable catheter - Google Patents

Abstract

A method of registering a real-time image feed from an imaging device inserted into a steerable catheter using a navigation system is provided. The method includes inserting the imaging device into a working channel of the steerable catheter and generating a real-time image feed of one or more reference points, wherein the orientation of the reference points is known. The method further includes orienting a handle of the steerable catheter to a neutral position, displaying the real-time image feed on a display of the navigation system, and registering the real-time image feed to the steerable catheter by rotating the displayed image so that the reference points in the real-time image feed are matched to the known orientation of the reference points.

Description

BACKGROUND
• The invention relates generally to medical devices and particularly to apparatuses and methods associated with a range of image guided medical procedures for detecting, sampling, staging and/or treating target tissues in the lungs of a patient.
• Image guided surgery (IGS), also known as image guided intervention (IGI), enhances a physician's ability to locate instruments within anatomy during a medical procedure. IGS can include 2-dimensional (2D), 3-dimensional (3D), and 4-dimensional (4D) applications. The fourth dimension of IGS can include multiple parameters either individually or together such as time, motion, electrical signals, pressure, airflow, blood flow, respiration, heartbeat, and other patient measured parameters.
• Although significant improvements have been made in these fields, a need remains for improved medical devices and procedures for visualizing, accessing, locating, real-time confirming while sampling and manipulating a target tissue.
SUMMARY OF THE INVENTION
• Among the various aspects of the present invention may be noted apparatuses for use in and methods associated with medical procedures; such apparatuses and methods, for example, may include apparatuses and methods that enhance a physician's ability to confirm the location of a target tissue within a patient during a medical procedure, such as image guided surgery (IGS) or image guided intervention (IGI) and such apparatuses and methods may further include apparatuses and methods that facilitate visualizing, accessing, locating, and manipulating the targeted tissue.
• Briefly, therefore, one aspect of the present invention is a method of confirming the location of a target tissue within a patient using a navigation system. The navigation system comprises a localization device, a display, and a pre-acquired image dataset of an airway of the patient. The navigation system is adapted to display images from the image dataset and to provide location information of a medical device within the patient in relation to a patient tracking device comprising a plurality of localization elements. The method comprises affixing the patient tracking device to an external surface of the patient, tracking the location of the patient tracking device using the navigation system, displaying an image from the image dataset on the display, wherein the displayed image is registered to the patient tracking device, and determining an initial location of the target tissue in the image dataset and navigating a steerable catheter through the airway of the patient to a position proximate the initial location. The steerable catheter has a proximal end portion and a distal end portion terminating in a tip, a working channel extending there between, and a localization element disposed proximate the distal end portion thereof. The method further comprises tracking the location of the localization element of the steerable catheter in the airway using the navigation system, generating information regarding the presence of the target tissue using a tissue sensing device inserted into the working channel of the steerable catheter, and determining a confirmed location of the target tissue using the generated information regarding the presence of the target tissue and the tracked location of the localization element. The method further comprises recording the confirmed location of the target tissue and, displaying the confirmed location of the target tissue on the display of the navigation system in an image from the image dataset.
• Another aspect of the present invention is a method of navigating a percutaneous needle to a target tissue within a patient using a navigation system. The navigation system comprises a localization device, a display, and a pre-acquired image dataset of an airway of the patient. The navigation system is adapted to display images from the image dataset and to provide location information of a medical device within the patient in relation to a patient tracking device comprising a plurality of localization elements. The method comprises affixing the patient tracking device to an external surface of the patient, tracking the location of the patient tracking device using the navigation system to monitor the respiratory state of the patient, and displaying an image from the image dataset on the display as a function of the monitored respiratory state, wherein the displayed image is registered to the patient tracking device. The method further comprises determining an initial location of the target tissue in the image dataset and navigating a steerable catheter through the airway of the patient to a position proximate the initial location. The steerable catheter has a proximal end portion and a distal end portion terminating in a tip, a working channel extending there between, and a localization element disposed proximate the distal end portion thereof. The method further comprises tracking the location of the localization element of the steerable catheter in the airway using the navigation system, generating one or more images of the target tissue using an imaging device inserted into the working channel of the steerable catheter, and determining a confirmed location of the target tissue in relation to the patient tracking device using the generated images and the tracked location of the localization element. The method further comprises recording the confirmed location of the target tissue, the recording comprising four-dimensional data comprising a three-dimensional location of the confirmed target tissue in relation to the patient tracking device and the respiratory state of the patient at the time the location of the target tissue was confirmed and applying the confirmed location of the target tissue to an image from the image dataset depicting the airway at the respiratory state of the patient at the time the location of the target tissue was confirmed. The method further comprises displaying the confirmed location of the target tissue on the display of the navigation system in an image from the image dataset, the displayed image depicting the airway at the respiratory state of the patient at the time the location of the target tissue was confirmed. Furthermore, the method comprises displaying a trajectory of a percutaneous device from an entry point on the patient's body to the confirmed location on the display of the navigation system, wherein the percutaneous device includes a localization element, inserting the percutaneous device into the patient and navigating the percutaneous device to the confirmed location, and intercepting the target tissue at the confirmed location.
• Another aspect of the present invention is a method of navigating a medical device to the confirmed location of the target tissue using indicia indicating the confirmed location of the target tissue and/or indicia indicating the location of the medical device. Thus the method may include displaying the confirmed location of the target tissue on the display of the navigation system without requiring that an image of the image dataset be displayed. This method of navigating a medical device to the confirmed location of the target tissue does not require re-registering one or more image datasets to the patient so long as the patient tracking device affixed to the patient does not move or the patient does not move relative to an electromagnetic field generator of the navigation system. Therefore, this method does not require displaying a hybrid “Inspiration-Expiration” 3D airway model, one or more images from one or more image datasets, a navigation pathway, and/or a real-time image feed from a bronchoscopic video camera, in order to permit a physician or other healthcare professional in navigating a medical device to the confirmed location of the target tissue.
• Another aspect of the present invention is directed to a method of registering a real-time image feed from an imaging device inserted into a steerable catheter using a navigation system comprising a display. The steerable catheter comprises an elongate flexible shaft having a proximal end portion, a distal end portion terminating in a tip, a working channel extending therebetween, and handle attached to the proximal end portion of the flexible shaft. The method comprises inserting the imaging device into the working channel of the steerable catheter, generating a real-time image feed of one or more reference points, wherein the orientation of the reference points is known, orienting the handle of the steerable catheter to a neutral position, displaying the real-time image feed on the display, and registering the real-time image feed to the steerable catheter by rotating the displayed image so that the reference points in the real-time image feed are matched to the known orientation of the reference points.
• Another aspect of the present invention is directed to a method of enhancing registration of the real-time image feed of a bronchoscopic video camera by correcting image distortion in the real time image feed. For example, bronchoscopic video cameras typically include fish-eye lenses which increase the field of view of the bronchoscopic video camera thus providing the physician or other healthcare professional with a larger view of the airway of the patient. However, the fish-eye lenses introduce barrel distortion into the real-time image feed. Due to this barrel distortion, the interpretation of the real-time image feed may be compromised. Correcting for this image distortion in the real-time image feed provides a more accurate depiction of the airway of the patient, thus permitting an enhanced registration of the real-time image feed.
• Yet another aspect of the present invention is directed to the construction and use of a hybrid “Inspiration-Expiration” 3D airway model. The hybrid “Inspiration-Expiration” 3D airway model may be used to reduce or eliminate errors in registration. Constructing the hybrid “Inspiration-Expiration” 3D airway model comprises calculating a population of deformation vector fields, wherein the deformation vector field(s) comprise vectors from one or more voxels in inspiration images or in aninspiration 3D airway model to one or more corresponding voxels in expiration images or in anexpiration 3D airway model. After the deformation vector field is calculated, the inspiration images and/or theinspiration 3D airway model may be deformed to the expiration state of the patient using the deformation vector field. Accordingly, the voxels in the inspiration images and/orinspiration 3D airway model are deformed to match the location, shape, and orientation of the airways of the patient at expiration. This results in the hybrid “Inspiration-Expiration” 3D airway model, wherein the hybrid “Inspiration-Expiration” 3D airway model contains the structural information of the airways of patient depicted in the inspiration images and/orinspiration 3D airway model. However, this structural information is now more closely matched to the location, shape, and orientation of the airways of the patient depicted in the expiration images and/orexpiration 3D airway model. Accordingly, the deformation vectors represent a change in location of the structure of the airway and a change in shape of the structure of the airway from inspiration to expiration.
• Yet another aspect of the present invention is directed to a method of injecting dye into a target tissue using a needle inserted into the working channel of a steerable catheter or using a needle inserted into the working channel of a percutaneous needle. Thus, when sampling the target tissue using a medical device inserted into the steerable catheter or percutaneous needle, the presence of dye in the sample provides an indication that the correct target tissue was sampled. This may be helpful, for example, in lung resections where there is significant movement of the lungs of the patient. For example, during lung resections there may be a gap between the chest wall and the lung and the physician or other healthcare profession may use a rigid scope to enter into the patient. Because the target tissue was previously dyed using a needle inserted into the working channel of steerable catheter or using a needle inserted into the working channel of the percutaneous needle, the physician or other healthcare professional may be able to visually see the dye. This may assist the physician or healthcare professional in sampling and/or treating the correct target tissue.
• Yet another aspect of the present invention is directed to a method of simulating and/or displaying a variety of image views using a navigation system based on the position and orientation (POSE) of a localization element in a steerable catheter, percutaneous device, and/or some other medical device. For example, the navigation system may be able to simulate and/or display axial images, coronal images, oblique images, orthogonal image slices, oblique or off-axis image slices, volume rendered images, segmented images, fused modality images, maximum intensity projection (MIPS) images, video, and video enhanced images. To simulate these views, the navigation system may modify one or more images from an image dataset using known image manipulation techniques. The images in the image dataset may be fluoroscopic images, ultrasound images, to computed tomography (CT) images, fused computed tomography-positron emission tomography (CT/PET) images, magnetic resonance imaging (MRI) images, etc.
BRIEF DESCRIPTION OF THE DRAWINGS
• The details of the present invention, both as to its construction and operation can best be understood with reference to the accompanying drawings, in which like numerals refer to like parts, and in which:
• FIG. 1 left perspective view of a patient tracking device on a patient according to an embodiment of the invention;
• FIG. 2 is a schematic illustration of an image analysis system according to an embodiment of the invention;
• FIG. 3 is a schematic illustration of a navigation system according to an embodiment of the invention;
• FIG. 4 is a graphical representation illustrating the function of the patient tracking device according to an embodiment of the invention;
• FIG. 5A is an illustration of a patient being imaged using an imaging device according to an embodiment of the invention;
• FIG. 5B is an illustration of a patient being imaged using an imaging device according to an embodiment of the invention;
• FIG. 5C is a schematic illustration of an image dataset according to an embodiment of the invention;
• FIG. 6A is a schematic illustration of aninspiration 3D airway model according to an embodiment of the invention;
• FIG. 6B is a schematic illustration of anexpiration 3D airway model according to an embodiment of the invention;
• FIG. 6C is a schematic illustration of a hybrid “Inspiration-Expiration” 3D airway model according to an embodiment of the invention;
• FIG. 7 is a front perspective view of a hybrid “Inspiration-Expiration” 3D airway model according to an embodiment of the invention;
• FIG. 8 is a schematic illustrating vector distances of the patient tracking device according to an embodiment of the invention;
• FIG. 9A is a schematic illustrating vector distances from a localization element on the patient tracking device according to an embodiment of the invention;
• FIG. 9B is a schematic illustrating vector distances from an image dataset according to an embodiment of the invention;
• FIG. 10 is a flowchart illustrating a method according to an embodiment of the invention;
• FIG. 11 is a left side view of a steerable catheter according to an embodiment of the invention;
• FIG. 11A is a left partial section view of a steerable catheter according to an embodiment of the invention;
• FIG. 12A is a left partial cut away view of a steerable catheter according to an embodiment of the invention;
• FIG. 12B is a left partial cut away view of a steerable catheter according to an embodiment of the invention;
• FIG. 13 is a left side view of a percutaneous needle according to an embodiment of the invention;
• FIG. 13A is a left partial cut away view of a percutaneous needle according to an embodiment of the invention;
• FIG. 14 illustrates a population of images which may be displayed on a display of a navigation system according to an embodiment of the invention;
• FIG. 15 is a flowchart illustrating a method of registering the real-time image feed from a bronchoscopic video camera to a steerable catheter according to an embodiment of the invention;
• FIG. 16 is a left perspective view of a steerable catheter in a jig for registering the real-time image feed from a bronchoscopic video camera to a steerable catheter according to an embodiment of the present invention;
• FIG. 16A is a front view of a steerable catheter in a jig for registering the real-time image feed from a bronchoscopic video camera to a steerable catheter according to an embodiment of the present invention;
• FIG. 16B is an image from a real-time image feed from a non-registered bronchoscopic video camera in a steerable catheter according to an embodiment of the present invention;
• FIG. 16C is an image from a real-time image feed from a registered bronchoscopic video camera in a steerable catheter according to an embodiment of the present invention;
• FIG. 17 is a flowchart illustrating a method of registering the real-time image feed from a bronchoscopic video camera to a steerable catheter according to an embodiment of the invention;
• FIG. 17A is a flowchart illustrating additional steps of a method of registering the real-time image feed from a bronchoscopic video camera to a steerable catheter according to an embodiment of the invention;
• FIG. 18A is an image of an expected orientation of anatomical features in the airway of the patient according to an embodiment of the invention;
• FIG. 18B is an image from a real-time image feed from a non-registered bronchoscopic video camera in a steerable catheter according to an embodiment of the present invention;
• FIG. 18C is an image from a real-time image feed from a registered bronchoscopic video camera in a steerable catheter according to an embodiment of the present invention;
• FIG. 19 is a section view of steerable catheter illustrating registering the real-time image feed from a bronchoscopic video camera to a steerable catheter and to a localization element of the steerable catheter according to an embodiment of the invention;
• FIG. 20A is a flowchart illustrating a portion of a method of confirming the location of a target tissue according to an embodiment of the invention;
• FIG. 20B is a flowchart illustrating a portion of a method of confirming the location of a target tissue according to an embodiment of the invention;
• FIG. 20C is a flowchart illustrating a portion of a method of confirming the location of a target tissue according to an embodiment of the invention;
• FIG. 20D is a flowchart illustrating a portion of a method of confirming the location of a target tissue according to an embodiment of the invention;
• FIG. 20E is a flowchart illustrating a portion of a method of confirming the location of a target tissue according to an embodiment of the invention;
• FIG. 21 is an image from an endobronchial ultrasound device according to an embodiment of the invention;
• FIG. 22 illustrates a population of images which may be displayed on a display of a navigation system according to an embodiment of the invention;
• FIG. 22A illustrates an enlarged view of an image which may be displayed on a display of a navigation system according to an embodiment of the invention; and
• FIG. 23 illustrates a population of images which may be displayed on a display of a navigation system according to an embodiment of the invention.
DETAILED DESCRIPTION
• The accompanying Figures and this description depict and describe embodiments of a navigation system (and related methods and devices) in accordance with the present invention, and features and components thereof. It should also be noted that any references herein to front and back, right and left, top and bottom and upper and lower are intended for convenience of description, not to limit the present invention or its components to any one positional or spatial orientation.
• Those of skill in the art will appreciate that in the detailed description below, certain well known components and assembly techniques have been omitted so that the present methods, apparatuses, and systems are not obscured in unnecessary detail.
• With larger volumes of patients expected to obtain lung cancer screening, obtaining definitive diagnoses may avoid numerous unneeded lung resections as about only 4% of patients from lung cancer screening are typically found to have a malignancy. However, peripheral target tissues (e.g., nodule, lesion, lymph node, tumor, etc.) that are smaller than 2 cm in size still present a difficult problem to solve. Typical bronchoscopes that are designed mainly for central airway inspection will be limited to the extent they can travel due to their large diameters before becoming wedged in the airway of the patient. Thus, to affect the 5 and 10 year survival rate of patient's that have target tissues which may be less than 2 cm in size, the apparatuses and methods as described herein allow for enhanced target tissue analysis for staging, intercepting target tissues in the periphery of the lungs that may not be accessible via airways, obtaining larger and higher quality tissue samples for testing, and provide a streamlined patient flow. Accordingly, the apparatuses and methods described herein enable a physician or other healthcare professional to initially determine the location of a target tissue and to confirm the location of the target tissue. In one embodiment, a hybrid “Inspiration-Expiration” 3D model may be used to provide patient specific 4D respiratory models which address peripheral respiratory motion. In certain patients, portions of the lungs including the upper lobes may move, on average, 15 mm between inspiration and expiration. Using a steerable catheter with an imaging device, such as a radial endobronchial ultrasound (EBUS) device inserted therein, a physician or other healthcare professional can determine a confirmed location of the target tissue. Additionally, apparatuses and methods described herein enable a physician or other healthcare professional to transition to a percutaneous approach to the target tissue, if needed. If the physician or other healthcare professional is unable to reach the target tissue for any reason, including but not limited to, the target tissue being below the surface of the airway (i.e., sub-surface target tissue), no airway proximate the target tissue, the pathway to the target tissue is very tortuous, or larger or additional tissue sample from a core biopsy is desired, the physician or other healthcare professional may insert navigated percutaneous needles to the confirmed location of the target tissue. Thus it will be understood that the apparatuses and methods described herein may be used to intercept target tissue(s) in the airway, on the wall of the airway, in the wall of the airway, and/or beyond the wall of the airway. That is, the apparatuses and methods described herein may be used to intercept target tissue(s) not only inside the airway, but may intercept target tissue(s) and other anatomical structures inside and/or beyond the wall of the airway. Thus in certain embodiments, sub-surface target tissue(s) may be intercepted.
• Additionally, the apparatuses and methods described herein provide easy to understand localization information to the physician or other healthcare professional, as well as display the preferred entry site and trajectory views of the percutaneous needle that are aligned to the target tissue. Once aligned, the physician or other healthcare professional may direct the percutaneous needle along the trajectory to the target tissue while viewing a display of the location of the tip of percutaneous needle on a navigation system as described herein. The physician or other healthcare professional may then intercept the target tissue in a variety of ways, including, but not limited to, performing a standard core biopsy, an aspiration, and/or delivering therapy using a variety of medical devices inserted through the percutaneous needle.
• As shown inFIG. 1, an apparatus according to an embodiment of the invention includes patient tracking device (PTD)20 comprising two ormore markers22 and two ormore localization elements24proximate markers22.Markers22 are visible in images captured by an imaging device and the position and orientation (POSE) oflocalization elements24 may be tracked by a localization device in an image analysis system and/or a navigation system.PTD20 comprises a population ofseparate pads26,28,30, each of which may include one ormore markers22 andlocalization elements24proximate markers22. First andsecond pads26,28 may each include onemarker22 and onelocalization element24.Third pad30 may include fourmarkers22 and fourlocalization elements24 located proximate the periphery ofthird pad30. Additionally,wires32,34,36 are used to connectlocalization elements24 in each of first, second, andthird pads26,28,30 to image analysis system50 (seeFIG. 2) and/or navigation system70 (seeFIG. 3). In alternative embodiments,localization elements24 may be wirelessly connected tonavigation system70.FIG. 1 illustratesPTD20 having sixmarkers22 and sixlocalization elements24, but any number of two ormore markers22 andlocalization elements24 can be used. Patient tracking device (PTD)20 can be coupled to a dynamic body such as, for example, a selected dynamic portion of the anatomy of apatient10.
• Markers22 are constructed of a material that can be viewed on an image, such as, for example, X-ray images or CT images. In certain embodiments,markers22 can be, for example, radiopaque such that they are visible via fluoroscopic imaging. In other embodiments, for example,markers22 may be echogenic such that they are visible via ultrasonic imaging. In yet other embodiments,markers22 may be both radiopaque and echogenic. In certain embodiments, for example,localization elements24 comprise six (6) degree of freedom (6 DOF) electromagnetic coil sensors. In other embodiments,localization elements24 comprise five (5) degree of freedom (5 DOF) electromagnetic coil sensors. In other embodiments,localization elements24 comprise other localization devices such as radiopaque markers that are visible via fluoroscopic imaging and echogenic patterns that are visible via ultrasonic imaging. In yet other embodiments,localization elements24 can be, for example, infrared light emitting diodes, and/or optical passive reflective markers.Localization elements24 can also be, or be integrated with, one or more fiber optic localization (FDL) devices.
• WhilePTD20 is shown comprising a population of separatepads containing markers22 andlocalization elements24, in certain embodiments,PTD20 may comprise onepad containing markers22 andlocalization elements24. In another embodiment, for example,PTD20 may includemarkers22 but notlocalization elements24. In another embodiment, for example,PTD20 may includelocalization elements24 but notmarkers22. In various embodiments,markers22 andlocalization elements24 can be the same device. In certain embodiments, for example,localization elements24 may function or serve asmarkers22.PTD20 can be a variety of different shapes and sizes. For example, in oneembodiment PTD20 is substantially planar, such as in the form of a pad that can be disposed at a variety of locations on a patient's10 body.PTD20 can be coupled topatient10 with adhesive, straps, hook and pile, snaps, or any other suitable coupling method. In another embodiment the PTD can be a catheter type device with a pigtail or anchoring mechanism that allows it to be attached to an internal organ or along a vessel.
• As described more fully elsewhere herein, an image analysis system is configured to receive image data associated with the dynamic body generated during a pre-surgical or pre-procedural first time interval. The image data can include an indication of a position of each ofmarkers22 for multiple instants in time during the first time interval. Then a navigation system can also receive position data associated withlocalization elements24 during a second time interval in which a surgical procedure or other medical procedure is being performed. The navigation system can use the position data received fromlocalization elements24 to determine a distance between thelocalization elements24 for a given instant in time during the second time interval. The navigation system can also use the image data to determine the distance betweenmarkers22 for a given instant in time during the first time interval. The navigation system can then find a match between an image where the distance betweenmarkers22 at a given instant in time during the first time interval is the same or substantially the same as the distance betweenlocalization elements24 associated with thosemarkers22 at a given instant in time during the medical procedure, or second time interval. Additionally, the navigation system can determine a sequence of motion of the markers and match this sequence of motion to the recorded motion of the markers over the complete procedure or significant period of time. Distance alone between the markers may not be sufficient to match the patient space to image space in many instances, the system may also determine the direction the markers are moving and the range and speed of this motion to find the appropriate sequence of motion for a complex signal or sequence of motion by the patient.
• A physician or other healthcare professional can use the images selected by the navigation system during a medical procedure performed during the second time interval. For example, when a medical procedure is performed on a targeted anatomy of a patient, such as a heart or lung, the physician may not be able to utilize an imaging device during the medical procedure to guide him to the targeted area within the patient. Accordingly,PTD20 can be positioned or coupled to the patient proximate the targeted anatomy prior to the medical procedure, and pre-procedural images can be taken of the targeted area during a first time interval.Markers22 ofPTD20 can be viewed with the image data, which can include an indication of the position ofmarkers22 during a given path of motion of the targeted anatomy (e.g., the heart) during the first time interval. Such motion can be due, for example, to inspiration (i.e., inhaling) and expiration (i.e., exhaling) of the patient, or due to the heart beating. During a medical procedure, performed during a second time interval, such as a procedure on a heart or lung, the navigation system receives data fromlocalization elements24 associated with a position oflocalization elements24 at a given instant in time during the medical procedure (or second time interval). The distance between selected pairs ofmarkers22 can be determined from the image data and the distance, range, acceleration, and speed between corresponding selected pairs oflocalization elements24 can be determined based on the position and orientation (POSE) data for given instants in time. Accordingly, the range of motion and speed ofmarkers22 can be calculated.
• Becauselocalization elements24 are proximate the location ofmarkers22, the distance between a selected pair oflocalization elements24 can be used to determine an intra-procedural distance between the pair ofcorresponding markers22. An image from the pre-procedural image data taken during the first time interval can then be selected where the distance between the pair of selectedmarkers22 in that image corresponds with or closely approximates the same distance determined usinglocalization elements24 at a given instant in time during the second time interval. This process can be done continuously during the medical procedure, producing simulated real-time, intra-procedural images illustrating the orientation and shape of the targeted anatomy as a catheter, sheath, needle, forceps, guidewire, fiducial delivery devices, therapy device, or similar medical device(s) is/are navigated to the targeted anatomy. Thus, during the medical procedure, the physician can view selected image(s) of the targeted anatomy that correspond to and simulate real-time movement of the anatomy. In addition, during a medical procedure being performed during the second time interval, such as navigating a catheter or other medical device or component thereof to a targeted anatomy, the location(s) of a localization element (e.g., an electromagnetic coil sensor) coupled to the catheter during the second time interval can be superimposed on an image of a catheter. The superimposed image(s) of the catheter can then be superimposed on the selected image(s) from the first time interval, providing simulated real-time images of the catheter location relative to the targeted anatomy. This process and other related methods are described in U.S. Pat. No. 7,398,116, entitled Methods, Apparatuses, and Systems Useful in Conducting Image Guided Interventions, filed Aug. 26, 2003, which is hereby incorporated by reference.
• Referring now toFIGS. 2 and 3, two systems which may be used during image guided surgery are described in detail. The first system illustrated inFIG. 2, isimage analysis system50.Image analysis system50 is used during generation of a population of images ofpatient10 during a first time interval, prior to a medical procedure being performed onpatient10. The second system, illustrated inFIG. 3, isnavigation system70.Navigation system70 is used during a medical procedure performed onpatient10 during a second time interval. As will be described,imaging system50 andnavigation system70 may include, in various embodiments, substantially similar or identical components. Accordingly,image analysis system50 andnavigation system70 may be able to carry out substantially similar or identical functions. In certain embodiments,image analysis system50 andnavigation system70 and may comprise a single system. In certain embodiments, for example,image analysis system50 may also function or serve as a navigation system. In certain embodiments, for example,navigation system70 may also function or serve as an image analysis system.
• As shown inFIG. 2,image analysis system50 comprises aprocessor52 havingmemory component54, input/output (I/O)component58, andoptional localization device56.Image analysis system50 may also optionally includedisplay60,electromagnetic field generator62, and/or user interface device(s)64 (e.g., keyboard, mouse).
• Image analysis system50 further includes and/or is in data communication withimaging device40.Imaging device40 can be, for example, a computed tomography (CT) device (e.g., respiratory-gated CT device, ECG-gated CT device), a magnetic resonance imaging (MRI) device (e.g., respiratory-gated MRI device, ECG-gated MRI device), an X-ray device, a 2D or 3D fluoroscopic imaging device, and 2D, 3D or 4D ultrasound imaging devices, or any other suitable medical imaging device. In one embodiment, for example,imaging device40 is a computed tomography-positron emission tomography (CT/PET) device that produces a fused computed tomography-positron emission tomography (CT/PET) image dataset. In the case of a two-dimensional imaging device, a population of two-dimensional images may be acquired and then assembled into volumetric data (e.g., three-dimensional (3D) image dataset) as is well known in the art using a two-dimensional to three-dimensional conversion. Pre-procedurally during a first time interval,imaging device40 can be used to generate a population of images ofpatient10 whilePTD20 is coupled topatient10; wherein the population of images depict the anatomy ofpatient10. The anatomy, may include, but is not limited to, the lungs, heart, liver, kidneys, and/or other organs ofpatient10. The population of images can be compiled into an image dataset. As stated above, some or allmarkers22 ofPTD20 are visible on the population of images and provide an indication of a position of some or all ofmarkers22 during the first time interval. The position ofmarkers22 at given instants in time through a path of motion ofpatient10 can be illustrated with the images.
• Processor52 ofimage analysis system50 includes a processor-readable medium storing code representing instructions to cause theprocessor52 to perform a process.Processor52 can be, for example, a commercially available personal computer, or a less complex computing or processing device that is dedicated to performing one or more specific tasks. For example,processor52 can be a terminal dedicated to providing an interactive graphical user interface (GUI) onoptional display60.Processor52, according to one or more embodiments of the invention, can be a commercially available microprocessor. Alternatively,processor52 can be an application-specific integrated circuit (ASIC) or a combination of ASICs, which are designed to achieve one or more specific functions, or enable one or more specific devices or applications. In yet another embodiment,processor52 can be an analog or digital circuit, or a combination of multiple circuits.
• Additionally,processor52 can includememory component54.Memory component54 can include one or more types of memory. For example,memory component54 can include a read only memory (ROM) component and a random access memory (RAM) component.Memory component54 can also include other types of memory that are suitable for storing data in a form retrievable byprocessor52. For example, electronically programmable read only memory (EPROM), erasable electronically programmable read only memory (EEPROM), flash memory, as well as other suitable forms of memory can be included within the memory component.Processor52 can also include a variety of other components, such as for example, coprocessors, graphic processors, etc., depending upon the desired functionality of the code.
• Processor52 can store data inmemory component54 or retrieve data previously stored inmemory component54. The components ofprocessor52 can communicate with devices external toprocessor52 by way of input/output (I/O)component58. According to one or more embodiments of the invention, I/O component58 includes a variety of suitable communication interfaces. For example, I/O component58 can include, for example, wired connections, such as standard serial ports, parallel ports, universal serial bus (USB) ports, S-video ports, local area network (LAN) ports, small computer system interface (SCSI) ports, and so forth. Additionally, I/O component58 can include, for example, wireless connections, such as infrared ports, optical ports, Bluetooth® wireless ports, wireless LAN ports, or the like. Embodiments ofimage analysis system50 which includedisplay60,electromagnetic field generator62, and/or user interface device(s)64, such components communicate withprocessor52 via I/O component58.
• Processor52 can be connected to a network, which may be any form of interconnecting network including an intranet, such as a local or wide area network, or an extranet, such as the World Wide Web or the Internet. The network can be physically implemented on a wireless or wired network, on leased or dedicated lines, including a virtual private network (VPN).
• As stated above,processor52 receives the population of images fromimaging device40.Processor52 identifies the position of selectedmarkers22 within the image data or voxel space using various segmentation techniques, such as Hounsfield unit thresholding, convolution, connected component, or other combinatory image processing and segmentation techniques.Processor52 determines a distance and direction between the position of any twomarkers22 during multiple instants in time during the first time interval, and stores the image data, as well as the position and distance data, withinmemory component54. Multiple images can be produced providing a visual image at multiple instants in time through the path of motion of the dynamic body.
• As stated above,processor52 can optionally include a receiving device orlocalization device56 for tracking the location oflocalization elements24 ofPTD20, as described more fully elsewhere herein. By trackinglocalization elements24 associated withPTD20 when the population of images are generated by imagingdevice40, the population of images may be gated. That is,image analysis system50 determines the respiratory phase at which the population of images were generated and this information may be stored in an image dataset and/or in another data store inmemory component54.
• In general,image analysis system50 may comprise any tracking system typically employed in image guided surgery, including but not limited to, an electromagnetic tracking system. An example of a suitable electromagnetic tracking subsystem is the AURORA electromagnetic tracking system, commercially available from Northern Digital Inc. (Waterloo, Ontario Canada). In one embodiment,image analysis system50 may include an electromagnetic tracking system, typically comprising an electromagnetic (EM)field generator62 that emits a series of electromagnetic fields designed to engulfpatient10, andlocalization elements24 coupled toPTD20. In certain embodiments, for example,localization elements24 are electromagnetic coils that receive an induced voltage from electromagnetic (EM)field generator62, wherein the induced voltage is monitored and translated bylocalization device56 into a coordinate position oflocalization elements24. In certain embodiments,localization elements24 are electrically coupled to twisted pair conductors to provide electromagnetic shielding of the conductors. This shielding prevents voltage induction along the conductors when exposed to the magnetic flux produced by the electromagnetic field generator.
• Accordingly,localization device56 can be, for example, an analog to digital converter that measures voltages induced ontolocalization elements24 in the field generated byEM field generator62; creates a digital voltage reading; and maps that voltage reading to a metric positional measurement based on a characterized volume of voltages to millimeters fromelectromagnetic field generator62. Position data associated withlocalization elements24 can be transmitted or sent tolocalization device56 continuously during imaging ofpatient10 during the first time interval. Thus, the position oflocalization elements24 can be captured at given instants in time during the first time interval. Becauselocalization elements24 areproximate markers22,localization device56 uses the position data oflocalization elements24 to deduce coordinates or positions associated withmarkers22 during the first time interval. The distance, range, acceleration, and speed between one or more selected pairs of localization elements24 (and corresponding markers22) is then determined and various algorithms are used to analyze and compare the distance between selectedelements24 at given instants in time, to the distances between and orientation among correspondingmarkers22 observed in a population of pre-procedural images.
• As shown inFIG. 3,navigation system70 comprises aprocessor72 havingmemory component74, input/output (I/O)component78, and localization device76.Navigation system70 also includesdisplay80, electromagnetic field generator82, and/or user interface device(s)84 (e.g., keyboard, mouse). In certain embodiments,navigation system50 further includes and/or is in data communication with imaging device40 (seeFIG. 2).
• Processor72 ofnavigation system70 includes a processor-readable medium storing code representing instructions to cause theprocessor72 to perform a process.Processor72 can be, for example, a commercially available personal computer, or a less complex computing or processing device that is dedicated to performing one or more specific tasks. For example,processor72 can be a terminal dedicated to providing an interactive graphical user interface (GUI) onoptional display80.Processor72, according to one or more embodiments of the invention, can be a commercially available microprocessor. Alternatively,processor72 can be an application-specific integrated circuit (ASIC) or a combination of ASICs, which are designed to achieve one or more specific functions, or enable one or more specific devices or applications. In yet another embodiment,processor72 can be an analog or digital circuit, or a combination of multiple circuits.
• Additionally,processor72 can includememory component74.Memory component74 can include one or more types of memory. For example,memory component74 can include a read only memory (ROM) component and a random access memory (RAM) component.Memory component74 can also include other types of memory that are suitable for storing data in a form retrievable byprocessor72. For example, electronically programmable read only memory (EPROM), erasable electronically programmable read only memory (EEPROM), flash memory, as well as other suitable forms of memory can be included within the memory component.Processor72 can also include a variety of other components, such as for example, coprocessors, graphic processors, etc., depending upon the desired functionality of the code.
• Processor72 can store data inmemory component74 or retrieve data previously stored inmemory component74. The components ofprocessor72 can communicate with devices external toprocessor72 by way of input/output (I/O)component78. According to one or more embodiments of the invention, I/O component78 includes a variety of suitable communication interfaces. For example, I/O component78 can include, for example, wired connections, such as standard serial ports, parallel ports, universal serial bus (USB) ports, S-video ports, local area network (LAN) ports, small computer system interface (SCSI) ports, and so forth. Additionally, I/O component78 can include, for example, wireless connections, such as infrared ports, optical ports, Bluetooth® wireless ports, wireless LAN ports, or the like. Additionally,display80, electromagnetic field generator82, and/or user interface device(s)84, communicate withprocessor72 via I/O component78.
• Processor72 can be connected to a network, which may be any form of interconnecting network including an intranet, such as a local or wide area network, or an extranet, such as the World Wide Web or the Internet. The network can be physically implemented on a wireless or wired network, on leased or dedicated lines, including a virtual private network (VPN).
• In general,navigation system70 may comprise any tracking system typically employed in image guided surgery, including but not limited to, an electromagnetic tracking system. An example of a suitable electromagnetic tracking subsystem is the AURORA electromagnetic tracking system, commercially available from Northern Digital Inc. (Waterloo, Ontario Canada). In one embodiment,navigation system70 may include an electromagnetic tracking system, typically comprising an electromagnetic (EM) field generator82 that emits a series of electromagnetic fields designed to engulfpatient10, andlocalization elements24 coupled toPTD20. In certain embodiments, for example,localization elements24 are electromagnetic coils that receive an induced voltage from electromagnetic (EM) field generator82, wherein the induced voltage is monitored and translated by localization device76 into a coordinate position oflocalization elements24. In certain embodiments,localization elements24 are electrically coupled to twisted pair conductors to provide electromagnetic shielding of the conductors. This shielding prevents voltage induction along the conductors when exposed to the magnetic flux produced by the electromagnetic field generator.
• Accordingly, localization device76 may be, for example, an analog to digital converter that measures voltages induced ontolocalization elements24 in the field generated by EM field generator82; creates a digital voltage reading; and maps that voltage reading to a metric positional measurement based on a characterized volume of voltages to millimeters from electromagnetic field generator82. Position data associated withlocalization elements24 may be transmitted or sent to localization device76 continuously during the medical procedure performed during the second time interval. Thus, the position oflocalization elements24 may be captured at given instants in time during the second time interval. Becauselocalization elements24 areproximate markers22, localization device76 uses the position data oflocalization elements24 to deduce coordinates or positions associated withmarkers22 during the second time interval. The distance, range, acceleration, and speed between one or more selected pairs of localization elements24 (and corresponding markers22) is then determined and various algorithms are used to analyze and compare the distance between selectedelements24 at given instants in time, to the distances between and orientation among correspondingmarkers22 observed in a population of pre-procedural images.
• Becauselocalization elements24 ofPTD20 may be tracked continuously during the first and/or second time intervals, a sequence of motion ofPTD20 that represents the motion of an organ ofpatient10 or the patient's10 respiratory cycle may be collected. Aspatient10 inhales and exhales, theindividual localization elements24 ofPTD20 will move relative to one another. That is, aspatient10 inhales, the distance between some or all oflocalization elements24 ofPTD20 may increase. Conversely, aspatient10 exhales, the distance between some or all oflocalization elements24 ofPTD20 may decrease. The sequence of motion oflocalization elements24 is tracked byimage analysis system50 and/ornavigation system70 andimage analysis system50 and/ornavigation system70 derives a respiratory signal based on the positions oflocalization elements24 during the respiratory cycle ofpatient10. The sequence of motion may then be analyzed to find unique similar points within the image dataset and images within the image dataset may be grouped.
• According to one particular embodiment, the respiratory signal derived fromPTD20 is used to gate the localization information of a medical device in the airway ofpatient10. In other embodiments, the respiratory signal derived fromPTD20 is used during the first time interval to gate the population of images generated by imagingdevice40. UsingPTD20 to derive a respiratory signal may assist in determining multiple airway models, for example, by performing a best fit of the real-time patient airway model to the image dataset to derive the optimal registration and gated period in the patient's respiratory cycle. Additionally or alternatively, the respiratory signal may be derived from devices other thanPTD20 that are known in the art for measuring the respiratory cycle of a patient. In certain embodiments, for example, a device that records the resistance between two locations on the patient may be used to measure the respiratory cycle. For example, such device a is similar to a variable potentiometer in that the resistance of the patient changes between two fixed points as the patient inhales and exhales. Thus, the resistance may be measured to create a respiratory signal. In other embodiments, a spirometer may be used to measure the respiratory cycle. In yet other embodiments, a cardiac signal may be used to gate the localization information of a medical device in the airway ofpatient10. It will be understood that any type of device for generating a cardiac signal may be used, including, but not limited to an ECG device,PTD20, etc.
• FIG. 4 is a schematic illustration indicating howmarkers22 ofPTD20 can move and change orientation and shape during movement ofpatient10. The graph is one example of how the lung volume can change during inhalation (inspiration) and exhalation (expiration) ofpatient10. The corresponding changes in shape and orientation ofPTD20 during inhalation and exhalation are also illustrated. The sixmarkers22 shown inFIG. 1 are schematically represented and labeled a, b, c, d, e, and f. As described above, a population of images ofPTD20 may be taken during a first time interval. The population of images include an indication of relative position of one ormore markers22; that is, one ormore markers22 are visible in the images, and the position of eachmarker22 is then observed over a period of time. A distance between any twomarkers22 may then be determined for any given instant of time during the first time interval. For example, a distance X between markers a and b is illustrated, and a distance Y between markers b and f is illustrated. These distances may be determined for any given instant in time during the first time interval from an associated image that illustrates the position and orientation ofmarkers22. As illustrated, during expiration ofpatient10 at times indicated as A and C, the distance X is smaller than during inspiration ofpatient10, at the time indicated as B. Likewise, the distance Y is greater during inspiration than during expiration. The distance between any pair ofmarkers22 may be determined and used in the processes described herein. Thus, the above embodiments are merely examples of possible pair selections. For example, a distance between a position of marker e and a position of marker b may be determined. In addition, multiple pairs or only one pair may be selected for a given procedure.
• FIGS. 5A and 5B illustrate the generation of a population of images during a first time interval usingimaging device40,PTD20, and optionallyelectromagnetic field generator62 ofimage analysis system50. InFIG. 5A,patient10 inhales andpatient10 is scanned usingimaging device40 which generates a population ofimages402 of the anatomy ofpatient10 andmarkers22 at inspiration. As shown,patient10 may place their arms above their head as they inhale, and this may be considered a total lung capacity (TLC) scan. InFIG. 5B,patient10 exhales andpatient10 is scanned usingimaging device40 which generates a population ofimages404 of the anatomy ofpatient10 andmarkers22 at expiration. As shown,patient10 may place their arms below their head, and this may be considered a functional residual capacity (FRC) scan. The Functional Residual Capacity is the lung volume at the end of a normal expiration, when the muscles of respiration are completely relaxed. At FRC (and typically at FRC only), the tendency of the lungs to collapse is exactly balanced by the tendency of the chest wall to expand. In various embodiments, the population ofimages402,404 may be two-dimensional (2D) images. In other embodiments, for example, the population ofimages402,404 may be three-dimensional (3D) images. Additionally, the population ofimages402,404 may be respiratory gated by tracking the location oflocalization elements24 ofPTD20 byimage analysis system50 and/ornavigation system70 usingEM field generator62,82 during image generation. In other embodiments, for example, the population ofimages402,404 may be gated using any type of device known for generating a physiological signal for gating.
• In various embodiments, for example, instead ofpatient10 holding an inspiration or expiration state, a cine loop of images may be generated in conjunction with the patient's respiratory cycle information fromPTD20. Thus the cine loop comprises a population of images generated from inspiration to expiration where the population of images are gated to the respiratory cycle ofpatient10 usingPTD20. This can serve to limit registration point selection, in order to be consistent with the patient's respiratory cycle that a 3D dataset such as CT, MR, or PET has acquired. This technique advantageously maximizes registration accuracy, a major flaw in conventional systems in the prior art.
• As described above,imaging device40 is in data communication withimage analysis system50 and/ornavigation system70 and sends, transfers, copies and/or provides the population ofimages402,404 taken during the first time interval associated withpatient10 to imageanalysis system50 and/ornavigation system70. As shown inFIG. 5C,image analysis system50 and/ornavigation system70 compiles the population ofimages402 at inspiration into a 3Dimage data subset406 of the anatomy ofpatient10 andmarkers22 at inspiration (referred to herein asinspiration 3D image data subset406). Additionally,image analysis system50 and/ornavigation system70 compiles the population ofimages404 at expiration into a 3Dimage data subset408 of the anatomy ofpatient10 at expiration (referred to herein asexpiration 3D image data subset408). Theinspiration 3Dimage data subset406 and theexpiration 3Dimage data subset408 are then stored in animage dataset400 inmemory component54,74 ofimage analysis system50 and/ornavigation system70.
• Additionally, acquiring a population of images at both inspiration and expiration may assist navigation of a steerable catheter during a second time interval. Referring now toFIGS. 6A-6C, in addition to segmenting themarkers22 ofPTD20 from the population ofimages402,404 generated during the first time interval,processor52 ofimage analysis workstation50 generates three-dimensional models of the airway ofpatient10 by segmenting the 3Dimage data subsets406,408. In various embodiments, segmentation of the airway may be accomplished using an iterative region growing technique wherein a seed voxel in the airway is selected as an initialization parameter. Voxels neighboring the seed voxel are then evaluated to determine whether they are a part of the airway, form the wall surrounding the airway, or form other tissue. Following segmentation, a surface mesh of the airway may be generated to produce a surface skeleton. The surface of the airway may then be rendered.
• As shown inFIG. 6A, a three-dimensional model of the airway ofpatient10 at inspiration (“inspiration3D airway model410”) is generated by segmenting theinspiration 3Dimage data subset406.FIG. 6A shows an Inspiration/arms-up pathway registration; this is, generally speaking, the preferred image scan acquisition state for automatic segmentation of the tracheo-bronchial tree.Processor52 may also segment one or more target tissues420 (e.g., lesions, lymph nodes, blood vessels, tumors, etc.) which may be navigated to during a second time interval using a variety of medical devices as described more fully elsewhere herein. The segmentation of the target tissue(s)420 may be refined to define different characteristics of the target tissue, such as, for example, density of the target tissue. Additional image data formats may also be loaded intoprocessor52, such as, for example, PET or MR andprocessor52 may be able to map the CT, PET, and/or MR data to one another.
• As shown atFIG. 6B, a three-dimensional model of the airway ofpatient10 at expiration (“expiration3D airway model412”) is generated by segmenting theexpiration 3Dimage data subset408. As discussed above, a variety of segmentation algorithms known in the art may be used to generate the inspiration andexpiration3D airway models410,412.FIG. 6B shows, in contrast toFIG. 6A, an FRC/arms-down segmentation. Because the patient's10 lungs are more full of air at inspiration than at expiration, theinspiration3D airway model410 includes more structure than theexpiration3D airway model412. Accordingly, as shown inFIG. 6B,expiration3D airway model412 includes fewer structure(s) and the structure(s) are in different locations and/or orientations than at inspiration. However during a procedure such as directing a navigated steerable catheter to a target tissue within the airway of patient10 (e.g., during a second time interval), the breathing cycle ofpatient10 may be closer to tidal breathing. That is,patient10 usually never reaches full inspiration during the procedure and thus if the segmentation of the airways ofpatient10 at inspiration is used for navigation purposes, there will be significant error in the registration of the segmented airway topatient10.
• In certain embodiments, a hybrid “Inspiration-Expiration”3D airway model414 is constructed as shown inFIG. 6C using theinspiration3D airway model410 and theexpiration3D airway model412. The hybrid “Inspiration-Expiration”3D airway model414 may be used to reduce or eliminate the errors in registration. To construct the hybrid “Inspiration-Expiration”3D airway model414, a population of deformation vector fields is calculated byprocessor52,72 ofimage analysis system50 and/ornavigation system70. The deformation vector field comprises vectors from one or more voxels in theinspiration3D airway model410 to one or more corresponding voxels in theexpiration3D airway model412. After the deformation vector field is calculated, theinspiration3D airway model410 is deformed to the expiration state ofpatient10 using the deformation vector field. Accordingly, the voxels in theinspiration3D airway model410 are deformed to match the location, shape, and orientation of the airways ofpatient10 at expiration. This results in the hybrid “Inspiration-Expiration”3D airway model414, wherein the hybrid “Inspiration-Expiration”3D airway model414 contains all of the structural information of the airways ofpatient10 depicted ininspiration3D airway model410. However, this structural information is now more closely matched to the location, shape, and orientation of the airways ofpatient10 depicted inexpiration3D airway model412. Accordingly, the deformation vectors represent not only a change in location of the structure of the airway but a change in shape of the structure of the airway from inspiration to expiration.
• FIG. 7, illustrates a 3D representation of hybrid “Inspiration-Expiration”3D airway model414 which includes atarget tissue420 segmented byprocessor52,72. This 3D representation of hybrid “Inspiration-Expiration”3D airway model414 may include surface information. Hybrid “Inspiration-Expiration”3D airway model414 may additionally includenavigation pathway416.Image analysis system50 and/ornavigation system70 may calculatenavigation pathway416 from the entry of the airway to the location oftarget tissue420. In certain embodiments,navigation pathway416 may be an optimal endobronchial path to a target tissue. For example,navigation pathway416 may represent the closest distance and/or closest angle to the target tissue. A physician or other healthcare professional may follownavigation pathway416 during an image guided intervention to reach the location oftarget tissue420.
• Althoughtarget tissue420 locations and navigation pathway(s)416 may be automatically calculated byimage analysis system50 and/ornavigation system70, a physician or other healthcare professional may manually adjusttarget tissue420 locations and/or navigation pathway(s)416.
• In general, the embodiments described herein have applicability in “Inspiration to Expiration”-type CT scan fusion. According to various methods, the user navigates on theexpiration 3Dimage data subset408 for optimal accuracy, while using theinspiration 3Dimage data subset406 to obtain maximum airway segmentation. In one embodiment, for example, a user could complete planning and pathway segmentation on theinspiration 3Dimage data subset406 ofpatient10. Preferably, a deformation vector field is created between at least two datasets (e.g., frominspiration 3Dimage data subset406 toexpiration 3D image data subset408). The deformation or vector field may then be applied to the segmented vessels and/or airways andnavigation pathway416 andtarget tissue420 locations. In these and other embodiments, the deformation or vector field may also be applied to multiple image datasets or in a progressive way to create a moving underlying image dataset that matches the respiratory or cardiac motion ofpatient10.
• By way of example, in certain embodiments, “Inspiration to Expiration” CT fusion using the lung lobe centroid and vector change to modify an airway model may also be applicable. In accordance with various embodiments, this technique is used to translate and scale each airway based on the lung lobe change between inspiration images and expiration images. The lung is constructed of multiple lobes and these lobes are commonly analyzed for volume, shape, and translation change. Each lobe changes in a very different way during the patient's breathing cycle. Using this information to scale and translate the airways that are located in each lobe, it is possible to adapt for airway movement. This scaled airway model may then be linked to the 4D tracking of the patient as described herein.
• In various aspects, the systems and methods described herein involve modifying inspiration images generated by imaging device40 (e.g., CT, CT/PET, MRI, etc.) to the expiration cycle for navigation. It is well understood that the patient's airways are contained within multiple lobes of the lung. It is also understood that airways significantly change between inspiration and expiration. In certain embodiments, to increase the accuracy of the map for navigation, it may be beneficial to include the detail of the inspiration images, coupled with the ability to navigate it accurately during expiration. For many patients, the expiration state may be the most repeatable point in a patient's breath cycle. In preferred embodiments, this modification may be carried out in accordance with the following steps:
• 1) Generate a population of images ofpatient10 at both inspiration and expiration usingimaging device40;
• 2) Segment the airways in both the inspiration and expiration images;
• 3) Segment the lung lobes in both the inspiration and expiration images (as the lung lobes are identifiable in both the inspiration and expiration images with a high degree of accuracy);
• 4) Determine a volume difference for each lung lobe between inspiration and expiration, use this change to shrink the airway size from the inspiration to the expiration cycle. Preferably, this is done for each individual lobe, as the percentage change will typically be different for each lobe.
• 5) Determine the centroid for each lung lobe and the vector change in motion from the main carina in both inspiration images and expiration images. This vector may then be used to shift the airways that are associated with each lung lobe. A centroid for the airway may be calculated based on the segmented branches. For each airway branch in the segmentation, it includes a tag that associates it with the respective lung lobe. The central airway including the main carina and initial airway branches for each lobe that is linked according to the expiration scan location of these points. Next, a plane may be defined using the main carina and initial airway branch exits to determine the vector change for each lobe.
• Among the lobes to modify, for example:
• left inferior lobe—the bottom lobe of the lung on the left side ofpatient10;
• left superior lobe—the top lobe of the lung on the left side ofpatient10.
• right inferior lobe—the bottom lobe of the lung on the right side ofpatient10;
• right middle lobe—the middle lobe of the lung on the right side ofpatient10;
• right superior lobe—the top lobe of the lung on the right side ofpatient10.
• Exemplary calculations are as follows:
• Inspiration Airway—Left Inferior Lobe (LIL)×70% (reduction in volume Inspiration to Expiration calculated)=ExAirwayLIL;
• Determine Expiration Central Airway points (Main Carina and Initial Airway branches) based upon segmentation;
• Shift ExAirwayLIL by vector distance (3 cm, 45 degrees up and back from main carina) that LIL centroid moved from inspiration to expiration.
• Preferably, this process is repeated for each lobe. In certain embodiments, the completion of5 lobes will result in a hybrid “Inspiration-Expiration” 3D airway model forpatient10.
• In various embodiments, the target location for the patient may be selected in the expiration images and applied to the hybrid “Inspiration-Expiration”3D airway model414. Alternatively, it may be selected in the inspiration images and adjusted based on the same or similar criteria as the inspiration airways. In either case, it may be adjusted individually or linked to the airway via a 3D network and moved in the same transformation.
• A deformation field may also be included in the analysis in various other embodiments described herein. For example, the deformation field may be applied to fuse 3D fluoroscopic images to CT images to compensate for different patient orientations, patient position, respiration, deformation induced by the catheter or other instrument, and/or other changes or perturbations that occur due to therapy delivery or resection or ablation of tissue.
• Following the generation of hybrid “Inspiration-Expiration”3D airway model414, during a second time interval, a medical procedure is then performed onpatient10 withPTD20 coupled topatient10 at the same location as during the first time interval when the population of pre-procedural images were taken. Preferably, the second time interval immediately follows the first time interval. However, in certain embodiments, second time interval may occur several hours, days, weeks or months after the first time interval. After hybrid “Inspiration-Expiration”3D airway model414 is generated and one ormore target tissues420 are identified and one ormore navigation pathways416 are calculated, this information is transferred fromimage analysis system50 tonavigation system70. This transfer may be done according to the DICOM (Digital Imaging and Communications in Medicine) standard as known in the art. It will be understood that the transfer may be done using any method and according to any standard without departing from the scope of the invention. For example, this transfer may be accomplished betweenimage analysis system50 tonavigation system70 using a variety of methods, including, but not limited to, a wired connection, a wireless connection, via CD, via a USB device, etc.
• It should be noted thatimage dataset400 may be supplemented, replaced or fused with an additional image dataset. In one embodiment, for example, during the second time interval an additional population of images may be taken. In other embodiments, for example, after the second time interval an additional population of images may be taken. By generating one or more additional image datasets, potential changed physical parameters of patient such aspatient10 movement, anatomical changes due to resection, ablation, general anesthesia, pneumothorax, and/or other organ shift may be accounted for during the procedure. Accordingly, images from CT-Fluoro, fluoroscopic, ultrasound or 3D fluoroscopy may be imported intoimage analysis system50 and/ornavigation system70.
• Using the respiratory signal derived fromPTD20,navigation system70 selects an image from the population ofpre-procedural images402,404 taken during the first time interval that indicates a distance or is grouped in a similar sequence of motion between correspondingmarkers22 at a given instant in time, that most closely approximates or matches the distance or similar sequence of motion between the selectedlocalization elements24. The process of comparing the distances is described in more detail below. Thus,navigation system70 displays images corresponding to the actual movement of the targeted anatomy during the medical procedure being performed during the second time interval. The images illustrate the orientation and shape of the targeted anatomy during a path of motion of the anatomy, for example, during inhaling and exhaling.
• FIG. 8 illustrates an example set of distances or vectors d1 through d6 between a set ofmarkers22, labeled m1 through m9 that are disposed at spaced locations onPTD20. As described above, a population of pre-procedural images is taken of a patient10 to whichPTD20 is coupled during a first time interval. The distances betweenmarkers22 are determined for multiple instants in time through the path of motion of the dynamic body (e.g., the respiratory cycle of the patient). Then, during a medical procedure, performed during a second time interval, localization elements24 (not shown inFIG. 8) proximate the location ofmarkers22 provide position data forlocalization elements24 to localization device76 (not shown inFIG. 8).Navigation system70 uses the position data to determine distances or vectors betweenlocalization elements24 for multiple instants in time during the medical procedure or second time interval.
• FIG. 9A shows an example of distance or vector data from localization device76. Vectors a1 through a6 represent distance data for one instant in time and vectors n1 through n6 for another instant in time, during a time interval from a to n. As previously described, the vector data may be used to select an image from the population of pre-procedural images that includes distances between the markers m1 through m9 that correspond to or closely approximate the distances a1 through a6 for time a, for example, between the localization elements. The same process may be performed for the vectors n1 through n6 captured during time n.
• One method of selecting the appropriate image from the population ofpre-procedural images402,404 is to execute an algorithm that sums all of the distances a1 through a6 and then search for and match this sum to an image containing a sum of all of the distances d1 through d6 obtained pre-procedurally from the image data that is equal to the sum of the distances a1 through a6. When the difference between these sums is equal to zero, the relative position and orientation of the anatomy or dynamic body D during the medical procedure will substantially match the position and orientation of the anatomy in the particular image. The image associated with distances d1 through d6 that match or closely approximate the distances a1 through a6 may then be selected and displayed. For example,FIG. 9B illustrates examples of pre-procedural images, Image a and Image n, of a dynamic body D that correspond to the distances a1 through a6 and n1 through n6, respectively. An example of an algorithm for determining a match is as follows:
• Does Σ a_i=Σ d_i(i=1 to 6 in this example) OR
• Does Σ(a_i−d_i)=0 (i=1 to 6 in this example).
• If yes to either of these, then the image is a match to the vector or distance data obtained during the medical procedure.
• FIG. 10 is a flowchart illustrating a method according to an embodiment of the invention. Amethod100 includes atstep102 generating image data during a pre-procedural or first time interval. As discussed above, a population of images are generated of a dynamic body, such aspatient10, using imaging device40 (e.g., CT Scan, MRI, etc.). The image data is associated with one or more images generated ofPTD20 coupled to a dynamic body, wherePTD20 includes two ormore markers22. In other words, the image data of the dynamic body is correlated with image data related toPTD20. The one or more images may be generated using a variety of different imaging devices as described previously. The image data include an indication of a position of a first marker and an indication of a position of a second marker, as illustrated atstep104. The image data include position data for multiple positions of the markers during a range or path of motion of the dynamic body over a selected time interval. As described above, the image data include position data associated with multiple markers, however, only two are described here for simplicity. A distance between the position of the first marker and the position of the second marker is determined for multiple instants in time during the first time interval, atstep106. As also described above, the determination may include determining the distance based on the observable distance between the markers on a given image. The image data, including all of the images received during the first time interval, the position, and the distance data is recorded in a memory component atstep108.
• Then atstep110, during a second time interval, while performing a medical procedure onpatient10 withPTD20 positioned onpatient10 at substantially the same location, position data is received for a first localization element and a second localization element.Localization elements24 ofPTD20 areproximate markers22, such that the position data associated withlocalization elements24 is used to determine the relative position ofmarkers22 in real-time during the medical procedure. The position data oflocalization elements24 are recorded in a memory component atstep112.
• A distance between the first and second localization elements is determined atstep114. Although only twolocalization elements24 are described, as with the markers, position data associated with more than two localization elements may be received and the distances between the additional localization elements may be determined.
• The next step is to determine which image from the population of images taken during the first time interval represents the relative position and/or orientation of the dynamic body at a given instant in time during the second time interval or during the medical procedure. To determine this, atstep116, the distance between the positions of the first and second localization elements at a given instant in time during the second time interval determined instep114 are compared to the distance(s) determined instep106 between the positions of the first and second markers obtained with the image data during the first time interval.
• An image is selected from the first time interval that best represents the same position and orientation of the dynamic body at a given instant in time during the medical procedure. To do this, the difference between the distance between a given pair of localization elements during the second time interval is used to select the image that contains the same distance between the same given pair of markers from the image data received during the first time interval. This is accomplished, for example, by executing an algorithm to perform the calculations. When there are multiple pairs of markers and localization elements, the algorithm may sum the distances between all of the selected pairs of elements for a given instant in time during the second time interval and sum the distances between all of the associated selected pairs of markers for each instant in time during the first time interval when the pre-procedural image data was received.
• When an image is found that provides the sum of distances for the selected pairs of markers that is substantially the same as the sum of the distances between the localization elements during the second time interval, then that image is selected atstep118. The selected image is then displayed atstep120. The physician or other healthcare professional may then observe the image during the medical procedure. Thus, during the medical procedure, the above process may be continuously executed such that multiple images are displayed and images corresponding to real-time positions of the dynamic body may be viewed.
• In addition to tracking the location ofPTD20, navigation system70 (seeFIG. 3) may also track any type of device which includes one or more localization elements. The localization elements in the medical devices may be substantially similar or identical tolocalization elements24 ofPTD20. The devices preferably include medical devices, including, but not limited to, steerable catheters, needles, stents, ablation probes, biopsy devices, guide wires, forceps devices, brushes, stylets, pointer probes, radioactive seeds, implants, endoscopes, energy delivery devices, therapy delivery devices, delivery of energy activated substances (e.g., porfimer sodium) and energy devices, radiofrequency (RF) energy devices, cryotherapy devices, laser devices, microwave devices, diffuse infrared laser devices, etc. In certain embodiments, the location of these devices are tracked in relation toPTD20. In other embodiments, for example, these devices are tracked in relation toelectromagnetic field generator62,82. It is also envisioned that at least some of these medical devices may be wireless or have wireless communications links. It is also envisioned that the medical devices may encompass medical devices which are used for exploratory purposes, testing purposes or other types of medical procedures.
• One embodiment of a medical device which may be tracked bynavigation system70 is illustrated inFIGS. 11 and 11A. In one embodiment of the present invention, a navigated surgical catheter that is steerable600 (referred herein to as “steerable catheter”) may be used to gain access to, manipulate, remove, sample or otherwise treat tissue within the body including, but not limited to, for example, heart or lung tissue.Steerable catheter600 comprises an elongateflexible shaft602 having aproximal end portion604, adistal end portion606 terminating intip607, and one or more workingchannels608 extending fromproximal end portion604 to tip607. As shown inFIG. 11A, one ormore localization elements610 that are detectable bynavigation system70 are disposed proximate thedistal end portion606 of elongateflexible shaft602. Accordingly, the position and orientation (POSE) oflocalization elements610 are tracked by localization device76 ofnavigation system70. The one ormore localization elements610 are connected bywire611 tonavigation system70; in alternative embodiments, the one ormore localization elements610 may be wirelessly connected tonavigation system70. In certain embodiments,localization elements610 comprise six (6) degree of freedom (6 DOF) electromagnetic coil sensors. In other embodiments,localization elements610 comprise five (5) degree of freedom (5 DOF) electromagnetic coil sensors. In other embodiments,localization elements610 comprise other localization devices such as radiopaque markers that are visible via fluoroscopic imaging and echogenic patterns that are visible via ultrasonic imaging. In yet other embodiments,localization elements610 may be, for example, infrared light emitting diodes, and/or optical passive reflective markers.Localization elements610 may also be, or be integrated with, one or more fiber optic localization (FDL) devices. Accordingly, in certain embodiments,localization elements610 may be substantially similar or identical tolocalization elements24 ofPTD20. In other embodiments the steerable catheter may be non-navigated, such that it does not include any localization elements.
• Steerable catheter600 further comprises handle612 attached to theproximal end portion604 of elongateflexible shaft602. Handle612 ofsteerable catheter600 includes steeringactuator614 whereindistal end portion606 is moved “up” and “down” relative toproximal end portion604 by manipulatingsteering actuator614 “up” and “down,” respectively. Additionally,distal end portion606 is moved “left” and “right” relative toproximal end portion604 by rotatinghandle612 “left” and “right,” respectively, about handlelongitudinal axis613. It will be understood that steeringactuator614 and handle612 are connected to a steering mechanism (not shown) on the inside ofsteerable catheter600 which is connected todistal end portion606 of elongateflexible shaft602 for causing the deflection indistal end portion606.Port616, disposed onhandle612, provides access to working channel(s)608 in elongateflexible shaft602 ofsteerable catheter600, such that a medical device may be inserted into working channel(s)608 throughport616.
• As shown inFIGS. 12A and 12B, any number of medical devices or therapies may be inserted into working channel(s)608 and/or extended out oftip607 to deliver the medical devices or therapies to a target tissue. The medical devices may include, but are not limited to,imaging devices633,tissue sensing devices632, biopsy devices, therapy devices, steerable catheters, endoscopes, bronchoscopes, percutaneous devices, percutaneous needles, pointer probes, implants, stents, guide wires, stylets, etc. In certain embodiments,imaging devices633 include, but are not limited to,bronchoscopic video cameras630, endobronchial ultrasound (EBUS)devices634, optical coherence tomography (OCT) devices, probe based Confocal Laser Endomicroscopy (pCLE) devices, or any known imaging device insertable into workingchannel608 ofsteerable catheter600.Tissue sensing device632 may be any type of device which may be used to determine the presence of a target tissue inpatient10. In certain embodiments,tissue sensing device632 may include, but is not limited to,imaging device633, a cell analysis device, a cancer detecting device, an exhaled breath condensate analyzer, a physiological characteristic sensor, a chemical analysis device, an aromatic hydrocarbon detection device, vacuum collection device, etc. The sensitivity of certain of the tissue sampling devices, such as aromatic hydrocarbon detection devices are dependent upon the density of the sample collected. Thus, by navigatingsteerable catheter600 near the desired target tissue a sample of higher density may be captured and analyzed. Additionally, a vacuum collection device may be navigated usingsteerable catheter600 to near the desired target tissue and/or an airway branch within one or two segments of the desired target tissue, and an air sample may be captured. In certain embodiments, therapy devices include, but are not limited to, ablation probes, energy delivery devices, radioactive seeds, delivery of energy activated substances (e.g., porfimer sodium) and energy devices, radiofrequency (RF) energy devices, cryotherapy devices, laser devices, microwave devices, diffuse infrared laser devices, fluids, drugs, combinations thereof, or the like). In certain embodiments, biopsy devices include, but are not limited to, needles, forceps devices, brushes, etc., In certain embodiments,steerable catheter600 may also include a suction capability.
• As illustrated inFIG. 12A, for example, in certain embodiments,imaging device633 is abronchoscopic video camera630.Bronchoscopic video camera630 may be inserted into workingchannel608 and/or extended outdistal end portion606 of navigatedsteerable catheter600. By insertingbronchoscopic video camera630 into workingchannel608 ofsteerable catheter600,steerable catheter600 may be used like a typical steerable bronchoscope, as described more fully elsewhere herein.
• As shown inFIG. 12B,tissue sensing device632 may be animaging device633, whereinimaging device633 is an endobronchial ultrasound (EBUS)device634; however, as described above, it will be understood thatimaging device633 may include, but is not limited to,bronchoscopic video camera630, an optical coherence tomography (OCT) device, a probe based Confocal Laser Endomicroscopy (pCLE) device, or any known imaging device insertable into workingchannel608 ofsteerable catheter600.
• In embodiments, wheretissue sensing device632 is imagingdevice633,imaging device633 may be able to generate a population of images of the target tissue(s), wherein the target tissue(s) may be in the airway, on the wall of the airway, in the wall of the airway, and/or beyond the wall of the airway. That is, the imaging device(s) may be able to generate images of target tissue(s) not only inside the airway, but may generate images of target tissue(s) and other anatomical structures inside and/or beyond the wall of the airway. Thus in certain embodiments, sub-surface target tissue may be imaged using the imaging device(s). Accordingly, using endobronchial ultrasound (EBUS)device634, an optical coherence tomography (OCT) device, a probe based Confocal Laser Endomicroscopy (pCLE) device, etc. while tracking the position and orientation (POSE) oflocalization element610 ofsteerable catheter600, as described herein, multiple 3D volumes of image data regarding target tissue(s) and other anatomical structures inside and/or beyond the wall of the airway may be collected and a larger 3D volume of collected data may be constructed. Knowing the 3D location and orientation of the multiple 3D volumes will allow the physician or other healthcare professional to view a more robust image of, for example, pre-cancerous changes of target tissue(s) inpatient10. This data may also be correlated to pre-acquired or intra-procedurally acquiredimage dataset400 to provide additional information.
• Additionally, in certain embodiments whereinsteerable catheter600 includes multiple workingchannels608, multiple medical devices may be inserted into the multiple workingchannels608. For example,bronchoscopic video camera630 may be inserted into one working channel and a medical device such as a needle, forceps device or a brush may be inserted into a second working channel. Accordingly, a real-time image feed frombronchoscopic video camera630 may be used to view the operation of the medical device. Although a steerable catheter has been described, it will be understood that any type of steerable medical device may be used in accordance with the methods described herein, including, but not limited to, endoscopes, bronchoscopes, etc. without departing from the scope of the invention.
• Another embodiment of a medical device which may be tracked bynavigation system70 is illustrated inFIGS. 13 and 13A. In one embodiment of the present invention, apercutaneous needle650 may be used to gain access to, manipulate, remove, sample or otherwise treat target tissue withinpatient10 including, but not limited to, for example, target tissue on and/or in the heart or lung.Percutaneous needle650 comprises an elongate shaft orcannula652 having aproximal end portion654, adistal end portion656 terminating intip657, and one or more workingchannels658 may extend fromproximal end portion654 to tip657.Percutaneous needle650 further includes handle652 attached to theproximal end portion654.Port667, disposed onhandle652, provides access to working channel(s)658 incannula652 ofpercutaneous needle650, such that a medical device may be inserted into working channel(s)658 throughport667. Any number of medical devices or therapies, as described herein, may be inserted into working channel(s)658 and/or extended out oftip657 to deliver the medical devices or therapies (e.g., steerable catheters, needles, stents, ablation probes, biopsy devices, guide wires, forceps devices, brushes, stylets, pointer probes, radioactive seeds, implants, endoscopes, energy delivery devices, therapy delivery devices, delivery of energy activated substances (e.g., porfimer sodium) and energy devices, radiofrequency (RF) energy devices, cryotherapy devices, laser devices, microwave devices, diffuse infrared laser devices, fluids, drugs, combinations thereof, or the like) to a target tissue.
• As shown inFIG. 13A, one ormore localization elements660 that are detectable bynavigation system70 are disposed proximate thedistal end portion656 ofcannula652. Accordingly, the position and orientation (POSE) oflocalization elements660 are tracked by localization device76 ofnavigation system70. The one ormore localization elements660 are connected bywire661 tonavigation system70; in alternative embodiments, the one ormore localization elements660 may be wirelessly connected tonavigation system70.
• In certain embodiments,localization elements660 comprise six (6) degree of freedom (6 DOF) electromagnetic coil sensors. In other embodiments,localization elements660 comprise five (5) degree of freedom (5 DOF) electromagnetic coil sensors. In other embodiments,localization elements660 comprise other localization devices such as radiopaque markers that are visible via fluoroscopic imaging and echogenic patterns that are visible via ultrasonic imaging. In yet other embodiments,localization elements660 may be, for example, infrared light emitting diodes, and/or optical passive reflective markers.Localization elements660 may also be, or be integrated with, one or more fiber optic localization (FDL) devices. Accordingly, in certain embodiments,localization elements660 may be substantially similar or identical tolocalization elements24 ofPTD20 and/orlocalization elements610 ofsteerable catheter600.
• Whilelocalization element660 is illustrated proximatedistal end portion656, it will be understood thatlocalization element660 may be located in other locations ofpercutaneous needle650 without departing from the scope of the invention. For example, in certain embodiments,localization element660 may be disposed proximate theproximal end portion654 and/or proximate handle662.Navigation system70 may be able to determine the location oftip657 in relation to the location ofPTD20 by knowing the location oflocalization element660 in relation to tip657. For example, iflocalization element660 is disposed at handle662, navigation system770 may be able to determine the location oftip657 in relation to the position oflocalization element660 if the length betweentip657 andlocalization element660 is input intonavigation system70.
• In other embodiments,percutaneous needle650 is non-navigated, such that it does not include any localization elements. However, the location ofpercutaneous needle650 may still be tracked bynavigation system70 if a medical device containing a localization element is inserted into workingchannel658 ofpercutaneous needle650.
• In various embodiments, any of the medical devices described herein that may be inserted into working channel(s)608,658 ofsteerable catheter600 and/orpercutaneous needle650 may be tracked individually with an integrated localization element (e.g., an electromagnetic (EM) sensor). Accordingly, the medical devices may be tip tracked. Additionally, wherein the inserted medical device is an ablation probe, ablation models may be displayed to assist in optimal placement of the ablation probe for treatment. It will be understood that the medical devices may be delivered endobronchially, percutaneously, and/or endobronchially and percutaneously simultaneously.
• Referring again tonavigation system70,navigation system70 may display ondisplay80 multiple images which may assist a physician or other healthcare professional in conducting the methods described herein.Image dataset400 generated during the first time interval may be registered topatient10 usingPTD20. As described above,localization elements24 ofPTD20 areproximate markers22 and because one ormore markers22 ofPTD20 are visible inimage dataset400 andlocalization elements24 corresponding to the one ormore markers22 are tracked bynavigation system70,image dataset400 may be registered topatient10. This registration may be manually accomplished or may be automatically accomplished bynavigation system70.
• In addition to or alternative toregistration using PTD20, registration may be completed by different known techniques. First, point-to-point registration may be accomplished by identifying points in an image space and then touching the same points in patient space. These points are generally anatomical landmarks that are easily identifiable on the patient. Second, lumen registration may be accomplished by generating a point cloud within the airways ofpatient10 and matching the shape of the generated point cloud to aninspiration3D airway model410, anexpiration3D airway model412, and/or a hybrid “Inspiration-Expiration”3D airway model414. Using four-dimensional tracking (4D) the point cloud may be generated at the appropriate respiration cycle to matchinspiration3D airway model410, anexpiration3D airway model412, and/or a hybrid “Inspiration-Expiration”3D airway model414. Generation of a point cloud is more fully described in U.S. Ser. No. 13/773,984, entitled “Systems, Methods and Devices for Forming Respiratory-Gated Point Cloud for Four Dimensional Soft Tissue Navigation,” filed on Feb. 22, 2013, which is hereby incorporated by reference. Third, surface registration may involve the generation of a surface inpatient10 space by either selecting multiple points or scanning, and then accepting the best fit to that surface in image space by iteratively calculating withprocessor72 until a surface match is identified. Fourth, repeat fixation devices entail repeatedly removing and replacing a device (i.e., dynamic reference frame, etc.) in known relation topatient10 or image fiducials ofpatient10. Fifth, two-dimensional (2D) image datasets may be registered to three-dimensional (3D) image datasets wherein, the two dimensional image datasets may include, but are not limited to, fluoroscopic images, ultrasound images, etc. and the three-dimensional (3D) image datasets may include, but are not limited, to computed tomography (CT) images, fused computed tomography-positron emission tomography (CT/PET) images, magnetic resonance imaging (MRI) images. Sixth, automatic registration may be accomplished by first attaching a dynamic reference frame topatient10 prior to acquiring image data. It is envisioned that other known registration procedures are also within the scope of the present invention, such as that disclosed in U.S. Pat. No. 6,470,207, entitled Navigational Guidance via Computer-Assisted Fluoroscopic Imaging”, filed on Mar. 23, 1999, which is hereby incorporated by reference.
• Afterimage dataset400 is registered topatient10,navigation system70 displays on display80 a variety of images as illustrated inFIG. 14. For example, as shown inpanel700, hybrid “Inspiration-Expiration”3D airway model414 may be displayed. Additionally, as shown inpanel700, an indicia718 (shown as a crosshair) of the location ofsteerable catheter600 is displayed. In certain embodiments, for example,indicia718 indicates the location ofdistal end portion606 ofsteerable catheter600. In other embodiments, for example,indicia718 indicates the location oflocalization element610 ofsteerable catheter600. In yet other embodiments, for example,indicia718 indicates the location oftip607 ofsteerable catheter600. That is,navigation system70 may be able to display an indicia indicating the location of a portion ofsteerable catheter600 based on the tracked location oflocalization element610. For example, iflocalization element610 is disposed 5 mm fromtip607 ofsteerable catheter600, the 5 mm distance may be taken into account bynavigation system70 and the indicia oftip607 indicating the location oftip607 may be displayed and not the location oflocalization element610. An indicia720 (shown as a circle) of an initial target tissue location may also be displayed ondisplay80 bynavigation system70 as shown inpanel700.Indicia718,720 are shown as a crosshair and circle, respectively; however it is envisioned that other indicia may be used to indicate the location ofsteerable catheter600, initial target tissue location, confirmed target tissue location, location ofpercutaneous needle650, and/or any other target tissue or medical device. For example, indicia may have different shapes, colors, sizes, line weights and/or styles, etc. without departing from the scope of the invention.
• Furthermore,navigation system70 may be able to simulate and display axial, coronal and oblique images based on the position and orientation (POSE) oflocalization element610 ofsteerable catheter600, as shown inpanels702,704, and706. To simulate these views,navigation system70 may modify one or more images fromimage dataset400 using known image manipulation techniques. Additionally,navigation system70 may simulate and/or display orthogonal image slices, oblique or off-axis image slices, volume rendered images, segmented images, fused modality images, maximum intensity projection (MIPS) images, video, and video enhanced images. As shown, indicia of718 ofsteerable catheter600 and/or anindicia720 of an initial target tissue location may also be displayed, as shown inpanels702,704, and706.
• In various embodiments as shown inpanel712,navigation system70 also simulates a virtual volumetric scene within the body ofpatient10, such as the airways ofpatient10, from a point of view of a medical device, such assteerable catheter600, as it is being navigated into and/or throughpatient10. This virtual volumetric scene is a computer-generated visualization of a bronchoscopy procedure and simulates what would be viewed by a bronchoscopic video camera inserted into the airways. To simulate the virtual volumetric scene,navigation system70 modifies one or more images fromimage dataset400 using known image manipulation techniques. For example,navigation system70 may be able to simulate the virtual volumetricscene using inspiration3D airway model410,expiration3D airway model412, and/or hybrid “Inspiration-Expiration”3D airway model414. Accordinglynavigation system70 renders an internal view of 3D airway model(s)410,412, and/or414 based on a virtual bronchoscope video camera position, for example, by applying certain surface properties (e.g., Lambertian), diffuse shading model(s), and perspective projection camera model(s). Virtual lighting and shading may be applied to the rendered view to further enhance the virtual volumetric scene. The field of view (FOV) may be changed to match the field of view of bronchoscopic video camera630 (seeFIG. 12A). The point of view may be adjusted to matchbronchoscopic video camera630 or to display a virtual volumetric scene from different points along the airway or outside the airway.Navigation system70 may also be able to display anavigation pathway416 in the virtual volumetric scene. Accordingly, the virtual volumetric scene may allow a physician or other healthcare professional to review thenavigation pathway416 prior to insertingsteerable catheter600 and/or other medical device intopatient10. Additionally, in certain embodiments, an indicia of the location oflocalization element610 ofsteerable catheter600 and/or an indicia of an initial target tissue location may also be displayed.
• Additionally, in various embodiments as shown inpanel716,navigation system70 also displays a real-time image feed frombronchoscopic video camera630 inserted into workingchannel608 ofsteerable catheter600. The real-time image feed may be static images or moving video. The real-time image feed may assist the physician or other healthcare professional in navigatingsteerable catheter600 to proximate the initial location of the target tissue. Thus by insertingbronchoscopic video camera630 into workingchannel608 of steerable catheter600 (seeFIG. 12A),steerable catheter600 may be used like a typical steerable bronchoscope. Typical steerable bronchoscopes are used to visually inspect the airways of a patient and have a fixed bronchoscopic video camera in addition to one or more working channels. Typical steerable bronchoscopes may have steering actuators and steering mechanisms that permit them to be steered much likesteerable catheter600. Because the bronchoscopic video camera of a typical steerable bronchoscope is fixed during manufacture of the steerable bronchoscope, the “up” orientation of the image feed from the bronchoscopic video camera as displayed to the physician or other healthcare professional is aligned with the “up” direction of the steering actuator of the typical steerable bronchoscope. That is, the orientation of the real-time image feed from the typical steerable bronchoscope is registered to the orientation of the steering directions of the typical steerable bronchoscope. Accordingly, when the physician or other healthcare professional steers the typical steerable bronchoscope “up,” the image feed will move “up.” Additionally, steering the typical steerable bronchoscope “down,” “left,” and “right,” the image feed will move “down,” “left,” and “right,” respectively.
• However, because the bronchoscopic video camera is fixed (i.e., non-removable) in the typical steerable bronchoscope, the outside diameter of the typical steerable bronchoscope must be large enough to also accommodate one or more working channels. Due to the large outside diameter of typical steerable bronchoscopes, certain portions of the airways may be unreachable by the steerable catheter because the diameter of the airway may be too small. Accordingly, it may be desirable to usesteerable catheter600 which may have a smaller outside diameter than the typical steerable bronchoscope.Bronchoscopic video camera630 may be inserted workingchannel608 ofsteerable catheter600 and a real-time image feed is displayed to the physician or other healthcare professional. Using the real-time image feed, the physician or other healthcare professional may navigatesteerable catheter600 to very small diameter portions of the airway which were previously inaccessible by a typical steerable bronchoscope. Once the physician or other healthcare professional has reached the desired target tissue withsteerable catheter600, the physician or other healthcare professional may removebronchoscopic video camera630 from workingchannel608 ofsteerable catheter600 and insert one or more other medical devices into workingchannel608 as described more fully elsewhere herein. Additionally, becausebronchoscopic video camera630 is not fixed insteerable catheter600, the ratio(s) of the diameter(s) of working channel(s)608 ofsteerable catheter600 to the outside diameter ofsteerable catheter600 may be much higher than the ratio(s) of the diameter(s) of working channel(s) of a typical steerable bronchoscope to the outside diameter of a typical steerable bronchoscope.
• While the removable nature ofbronchoscopic video camera630 provides the above mentioned benefits, because thebronchoscopic video camera630 is not fixed insteerable catheter600, the “up” orientation of the image feed frombronchoscopic video camera630 as displayed to the physician or other healthcare professional may not be aligned with the “up” direction ofsteering actuator614 ofsteerable catheter600. That is, depending on how the physician or other healthcare professional insertsbronchoscopic video camera630 into workingchannel608 of steerable catheter, what appears as “up” in the real-time image feed frombronchoscopic video camera630 may not correspond to an “up” steering input to steeringactuator614. Accordingly, the real time image feed may be rotated relative to the expected steering direction. This may introduce uncertainty and or confusion to the physician or other healthcare professional. For example, the physician or other healthcare professional may see an airway on the left hand side of the displayed real-time image feed and may accordingly manipulatehandle612 of steerable catheter to causedistal end portion606 ofsteerable catheter600 to steer left. However, because the orientation of the real-time image feed is not aligned with the withsteering actuator614 ofsteerable catheter600, the airway that the physician or other healthcare professional thought was on the left hand side of the real-time image feed is not actually reachable by a left hand steering input tosteerable catheter600. Accordingly, the orientation of the image feed frombronchoscopic video camera630 as displayed to the physician or other healthcare professional may not be aligned withsteering actuator614 ofsteerable catheter600. Thus, to ensure that the physician or other healthcare professional is navigating down the desired airway, the “up” orientation of the real-time image feed frombronchoscopic video camera630 as displayed to the physician or other healthcare professional should be aligned with the “up” direction ofsteering actuator614 ofsteerable catheter600.
• Referring now toFIG. 15, one method of registering the real-time image feed from abronchoscopic video camera630 to asteerable catheter600 is described. Atstep900,bronchoscopic video camera630 is inserted into workingchannel608 ofsteerable catheter600. In certain embodiments, tip631 (seeFIG. 12A) ofbronchoscopic video camera630 is positioned proximate or extendedpast tip607 ofsteerable catheter600. Atstep902, a real-time image feed of one or more reference points is generated usingbronchoscopic video camera630, wherein the orientation of the reference point(s) is known. That is, the physician or other healthcare professional may know or ascertain the orientation of the reference point(s) independently from the real-time image feed. Atstep904, the physician or other healthcare professional orients handle612 ofsteerable catheter600 to a neutral position. Preferably, handle612 ofsteerable catheter600 is considered to be in a neutral position whenlongitudinal axis613 ofhandle612 is substantially vertical, when no “up” or “down” steering input is applied tosteerable catheter600 by steeringactuator614, and when no “left” or “right” steering input is applied tosteerable catheter600 by rotation ofhandle612 aboutlongitudinal axis613. When in the neutral position, it is not required that elongateflexible shaft602 ofsteerable catheter600 be straight. Elongateflexible shaft602 may be flexed; however it is contemplated that no additional steering inputs are applied tosteerable catheter600.
• Atstep906, the real-time image feed ofbronchoscopic video camera630 is displayed ondisplay80 ofnavigation system70. Atstep908, the real-time image feed is registered tosteerable catheter600 by rotating the displayed real-time image feed so that the reference point(s) in the real-time image feed are matched to the known orientation of the reference point(s). In certain embodiments, the physician or healthcare professional manually rotates the real-time image feed ondisplay80 ofnavigation system70 using user interface device84 (e.g., keyboard, mouse). In other embodiments, for example,navigation system70 may automatically rotate the real-time image feed ondisplay80 ofnavigation system70.
• Optionally, the registration may be confirmed by steeringsteerable catheter600 to cause a deflection ofdistal end portion606 of elongateflexible shaft602 in a direction and observing that the displayed real-time image feed moves in that same direction. For example, if physician or other healthcare professional manipulates steeringactuator614 to cause an “up” deflection indistal end portion606 of elongateflexible shaft602, the displayed real-time image feed will also move “up.” Similarly, if the physician or other healthcare professional manipulates steeringactuator614 to cause a “down” deflection indistal end portion606 of elongateflexible shaft602, the displayed real-time image feed will also move “down.” Additionally, if the physician or other healthcare professional rotates handle612 “left” or “right” to cause a “left” or “right” deflection indistal end portion606 of elongateflexible shaft602, the displayed real-time image feed will also move “left” or “right.” Accordingly, after the real-time image feed is registered tosteerable catheter600, what is displayed as “up,” “down,” “left,” and/or “right,” corresponds to “up,” “down,” “left,” and “right” steering inputs tosteerable catheter600. That is, the orientation of the displayed real-time image feed is matched to the steering mechanics ofsteerable catheter600.
• As shown in FIGS.16 and16A-16C, ajig802 may be used in conjunction with the method of registering the real-time image feed from abronchoscopic video camera630 to asteerable catheter600 described inFIG. 15. As shown inFIG. 16,jig802 may includereceiver803 into whichdistal end portion606 ofsteerable catheter600 may be placed.Jig802 further includes threeround objects804 which serve as the reference points described above. Accordingly, when viewed along arrow A, round objects804 are known to be oriented as shown inFIG. 16A. When placed injig802,bronchoscopic video camera630 is inserted into workingchannel608 ofsteerable catheter600 and handle612 ofsteerable catheter600 is oriented in a neutral position, as described above. Thus if the threeround objects804 are rotated a certain angle in the displayed real-time image feed frombronchoscopic video camera630 as shown inFIG. 16B, the real-time image feed needs to be registered by rotating the displayed real-time image feed so that the threeround objects804 in the real-time image feed are matched to the known orientation of the threeround objects804 as shown inFIG. 16C. While reference points are illustrated as threeround objects804, it will be understood that any shape object may be used as a reference point, including, but not limited to, a T-shaped object, a cross-shaped object, a square shaped object, etc. Additionally, while three reference points are illustrated, it will be understood thatjig802 may include one or more reference points. In other embodiments, for example,jig802 may include a picture or pattern which serves as the one or more reference points.
• Another embodiment of the method of registering the real-time image feed from abronchoscopic video camera630 to asteerable catheter600 is shown inFIG. 17. Atstep910,bronchoscopic video camera630 is inserted into workingchannel608 ofsteerable catheter600. In certain embodiments, tip631 (seeFIG. 12A) ofbronchoscopic video camera630 is positioned proximate or extendedpast tip607 ofsteerable catheter600. Atstep912,steerable catheter600 is inserted into the airway ofpatient10. Atstep914, a real-time image feed of one or more reference points is generated usingbronchoscopic video camera630, the reference point(s) comprising anatomical feature(s) of the airway wherein the orientation of the anatomical feature(s) is known. In certain embodiments, the anatomical feature(s) may include the right main bronchus (RMB) and the left main bronchus (LMB).
• As shown inFIG. 18A, it is generally understood that the RMB and the LMB of most patients are oriented at about a 3 o'clock position and about a 9 o'clock position respectively when viewed with a typical steerable bronchoscope. Referring again toFIG. 17, atstep916, the physician or other healthcare professional orients handle612 ofsteerable catheter600 to a neutral position. Preferably, handle612 ofsteerable catheter600 is considered to be in a neutral position whenlongitudinal axis613 ofhandle612 is substantially vertical, when no “up” or “down” steering input is applied tosteerable catheter600 by steeringactuator614, and when no “left” or “right” steering input is applied tosteerable catheter600 by rotation ofhandle612 aboutlongitudinal axis613. When in the neutral position, it is not required that elongateflexible shaft602 ofsteerable catheter600 be straight. Elongateflexible shaft602 may be flexed; however it is contemplated that no additional steering inputs are applied tosteerable catheter600.
• Atstep918, the real-time image feed ofbronchoscopic video camera630 is displayed ondisplay80 ofnavigation system70. As shown inFIG. 18B, the displayed real-time image feed ofbronchoscopic video camera630 shows the RMB and LMB rotated such that the RMB appears at about a 2 o'clock position and the LMB appears at about an 8 o'clock position. Atstep920, the real-time image feed is registered tosteerable catheter600 by rotating the displayed real-time image feed so that the anatomical feature(s) in the real-time image feed are matched to the known orientation of the anatomical feature(s). Thus as shown inFIG. 18C, after registration, the displayed real-time image feed ofbronchoscopic video camera630 shows the RMB and LMB at about a 3 o'clock position and at about a 9 o'clock position, respectively. In certain embodiments, the physician or healthcare professional manually rotates the real-time image feed ondisplay80 ofnavigation system70 using user interface device84 (e.g., mouse). In other embodiments, for example,navigation system70 may automatically rotate the real-time image feed ondisplay80 ofnavigation system70. The method may optionally continue according to steps illustrated inFIG. 17A as described more fully elsewhere herein.
• Optionally, the registration may be confirmed by steeringsteerable catheter600 to cause a deflection ofdistal end portion606 of elongateflexible shaft602 in a direction and observing that the displayed real-time image feed moves in that same direction. For example, if physician or other healthcare professional manipulates steeringactuator614 to cause an “up” deflection indistal end portion606 of elongateflexible shaft602, the displayed real-time image feed will also move “up.” Similarly, if the physician or other healthcare professional manipulates steeringactuator614 to cause a “down” deflection indistal end portion606 of elongateflexible shaft602, the displayed real-time image feed will also move “down.” Additionally, if the physician or other healthcare professional rotates handle612 “left” or “right” to cause a “left” or “right” deflection indistal end portion606 of elongateflexible shaft602, the displayed real-time image feed will also move “left” or “right.” Accordingly, after the real-time image feed is registered tosteerable catheter600, what is displayed as “up,” “down,” “left,” and “right,” corresponds to “up,” “down,” “left,” and “right” steering inputs tosteerable catheter600.
• In some embodiments, the registration of the real-time image feed tosteerable catheter600 may be enhanced by correcting image distortion in the real time image feed. For example, bronchoscopic video cameras typically include fish-eye lenses which increase the field of view of the bronchoscopic video camera thus providing the physician or other healthcare professional with a larger view of the airway ofpatient10. However, the fish-eye lenses introduce barrel distortion into the real-time image feed. Due to this barrel distortion, the interpretation of the real-time image feed may be compromised. Correcting for this image distortion in the real-time image feed provides a more accurate depiction of the airway ofpatient10, thus permitting an enhanced registration of the real-time image feed tosteerable catheter600.
• Referring again toFIG. 14, in yet other embodiments, the virtual volumetric scene displayed inpanel712 may be registered to the real-time image feed from abronchoscopic video camera630 displayed inpanel716. However, assteerable catheter600 is navigated through the airways ofpatient10,steerable catheter600 may be positioned in such a way such that what appears “up” in the real-time image feed may not correspond to the physical “up” direction ofpatient10. That is, the physical “up” ofpatient10 usually corresponds to the anterior direction ofpatient10 aspatient10 is oriented during the procedure. Typically,patient10 is in the supine position and thus, the physical “up” of the patient will correspond to an actual “up.” However, in certain situations,patient10 may be in different orientations during the procedure, such as on their side or chest However, the virtual volumetric scene displayed inpanel712 is shown with the chest ofpatient10 facing up. Accordingly, the real-time image feed as shown inpanel716 may not match the virtual volumetric scene displayed inpanel712. To assist the physician or other healthcare professional in navigating down the correct airway, the virtual volumetric scene may be registered to the real-time image feed, wherein the real-time image feed has been registered tosteerable catheter600.
• In some embodiments, image correction is applied to the real-time image feed to assist in registering the virtual volumetric scene to the real-time image feed. To register the virtual volumetric scene as shown inpanel712 with the real-time image feed frombronchoscopic video camera630 as shown inpanel716, the lens distortion of the real-time image feed must be corrected or the same lens distortion must be applied to the virtual volumetric scene.
• After correcting the real-time image feed for lens distortion, virtual volumetric scene is registered to the real-time image feed. An initial registration may be performed in a region of the airway that is easily locatable withsteerable catheter600, such as the trachea for example. Thus the virtual volumetric scene as shown inpanel712 may be manually or automatically rotated to match one or more airway structure(s) (e.g., RMB and LMB) visible in both the virtual volumetric scene and the real-time image. In various embodiments, a matching algorithm may then be used to maintain registration of the virtual volumetric scene to the real-time image feed assteerable catheter600 is navigated through the airway. Other registration methods known in the art may also be applied without departing from the scope of the invention. For example, the virtual volumetric scene may be registered to the real-time image feed using intensity based maximization of information mutual to the real-time image feed and the virtual volumetric scene instead of matching structures. In other embodiments, for example, surface normals of the real-time image feed may be calculated using a linear shape from shading algorithm based on the unique camera and/or lighting configurations ofbronchoscopic video camera630. The virtual volumetric scene may then be registered to the real-time image feed by matching the calculated surface normal with surface normal of the virtual volumetric scene. Accordingly, the registration of the virtual volumetric scene to the real-time image feed may cause both the real-time image feed and the virtual volumetric scene to be displayed ondisplay80 with “up” as “up.”
• In yet other embodiments, the registration of the virtual volumetric scene to the real-time image feed may be enhanced by registering the real-time image feed tolocalization element610 ofsteerable catheter600. By registering the real-time image feed tolocalization element610, both the real-time image feed and/or the virtual volumetric scene may be shown in the “up” orientation ondisplay80 no matter what the position and orientation (POSE) oflocalization element610 insteerable catheter600 is as tracked bynavigation system70. The physician or other healthcare professional may always expect that an “up” steering input onsteering actuator614 will always result in the displayed real-time image moving “up.” Thus, even if physician or other healthcare professional moves handle612 of steerable catheter such thatlongitudinal axis613 is not substantially vertical and thereby causes a rotation ofdistal end portion606 ofsteerable catheter600, because the real-time image feed is registered tosteerable catheter600 and tolocalization element610,navigation system70 may display real-time image feed and/or virtual volumetric scene with “up” as “up.” Accordingly, the physician or other healthcare professional may still be able to easily determine how to manipulatesteering actuator614 ofsteerable catheter600 to navigatesteerable catheter600 alongnavigation pathway416 displayed inpanel712.
• Referring now toFIG. 17A, a method of registering the real-time image feed frombronchoscopic video camera630 tolocalization element610 ofsteerable catheter600 is described. Preferably, registration of the real-time image feed frombronchoscopic video camera630 tolocalization element610 ofsteerable catheter600 is performed after the real-time image feed frombronchoscopic video camera630 is registered tosteerable catheter600. Atstep922,navigation system70 tracks the location oflocalization element610 ofsteerable catheter600. Atstep924, the orientation of the registered real-time image feed with respect tolocalization element610 is determined. Referring now toFIG. 19, a section view ofsteerable catheter600 is shown to aid in describing the registration of the real-time image feed frombronchoscopic video camera630 tolocalization element610 ofsteerable catheter600. For purposes of simplicity not all structure ofsteerable catheter600,localization element610, andbronchoscopic video camera630 are illustrated. As shown inFIG. 19, O_irepresents the un-registered orientation of the real-time image feed frombronchoscopic video camera630. O_Rrepresents the orientation of the real-time image feed frombronchoscopic video camera630 after the real-time image feed frombronchoscopic video camera630 is registered tosteerable catheter600. Thus during registration of the real-time image feed frombronchoscopic video camera630 tosteerable catheter600, the real-time image feed was rotated by angle θ (seeFIGS. 15,17steps908,920 respectively).
• Thus, referring again toFIG. 17A, determining the orientation of the registered real-time image feed with respect tolocalization element610 atstep924, comprises determining the angle β from O_Rto the tracked location oflocalization element610. Atstep926, the determined orientation (e.g., angle β) is recorded tonavigation system70. Accordingly, after the real-time image feed frombronchoscopic video camera630 is registered tolocalization element610 ofsteerable catheter600, the real-time image feed and/or the virtual volumetric scene may be shown in the “up” orientation ondisplay80 regardless of the position and orientation (POSE) oflocalization element610 insteerable catheter600 as tracked bynavigation system70. Additionally, by registering the real-time image feed frombronchoscopic video camera630 tolocalization element610 ofsteerable catheter600, the registration of the virtual volumetric scene may be maintained to the real-time image feed assteerable catheter600 is navigated in the airway ofpatient10.
• In various embodiments as described above, registering the real-time image feed from abronchoscopic video camera630 to asteerable catheter600 permits displaying one or more navigational aids over the real-time image feed frombronchoscopic video camera630, wherein the navigational aids are registered to the real-time image feed. In certain embodiments, the navigational aids may be determined using the hybrid “Inspiration-Expiration”3D airway model414. For example, in certain embodiments,navigation system70 mayoverlay navigation pathway416 onto the real-time image feed frombronchoscopic video camera630. In other embodiments, for example, navigation system may also overlay directional cues such as arrows or other indicators on the real-time image feed frombronchoscopic video camera630. Integrating navigational aids, including but not limited tonavigation pathway416 and/or directional cues, with the real-time image feed may assist the physician or other healthcare professional in navigatingsteerable catheter600 to the desired target tissue. Accordingly, in certain embodiments wherein navigational aids are overlaid onto real-time image feed, a virtual volumetric scene does not need to be displayed ondisplay80 ofnavigation system70.
• Although registering the real-time image feed from abronchoscopic video camera630 to asteerable catheter600 has been described in detail herein, it will be understood that image feeds fromother imaging devices633 inserted into workingchannel608 ofsteerable catheter600 may be registered in similar manners. Theimaging devices633 may include, but are not limited to, endobronchial ultrasound (EBUS) device634 (seeFIG. 12B), an optical coherence tomography device (OCT), and probe based Confocal Laser Endomicroscopy (pCLE).
• Returning toFIG. 14,navigation system70 may also display agraphical representation708 of the respiratory cycle ofpatient10 monitored usingPTD20. In certain embodiments, one or more of the images and/or indicia displayed inpanels700,702,704,706,712 and716 are displayed as a function of the monitored respiratory state. That is, images inimage dataset400 and/or generated fromimage dataset400 are displayed ondisplay80 that depict the anatomy ofpatient10 at the monitored respiratory state. For example, when the patient is at expiration as monitored byPTD20, images of the anatomy of the patient depicting the anatomy at expiration are displayed. Accordingly, when the patient is at inspiration as monitored byPTD20, images of the anatomy ofpatient10 depicting the anatomy at inspiration are displayed. In other embodiments, one or more of the images displayed inpanels700,702,704,706,712 and716 may not be displayed as a function of the monitored respiratory state. That is, images inimage dataset400 and/or generated fromimage dataset400 are displayed ondisplay80 that depict the anatomy ofpatient10 at one respiratory state. For example, when the patient is at expiration and inspiration as monitored byPTD20, images of the anatomy ofpatient10 depicting the anatomy at expiration are displayed. In embodiments where images are not displayed according to the monitored respiratory state, anindication710 of whether the displayed images match the monitored respiratory state may be shown (e.g., “Respiration Matched”, “Respiration out of Sync”).
• Additionally, the display of indicia of the locations of the target tissue and/or indicia of the location of various medical devices may be synchronized or gated with an anatomical function, such as the cardiac or respiratory cycle, ofpatient10. That is, in certain embodiments, the indicia are displayed ondisplay80 as a function of the monitored respiratory state. In certain instances, the cardiac or respiratory cycle ofpatient10 may cause the indicia to flutter or jitter withinpatient10. In these instances, the indicia will likewise flutter or jitter on the image(s) displayed ondisplay80.
• To eliminate the flutter of the indicia on the displayed image(s), the position and orientation (POSE) oflocalization elements610,660 is acquired at a repetitive point within each cycle of either the cardiac cycle or the respiratory cycle ofpatient10. To synchronize the acquisition of position data forlocalization elements610,660,navigation system70 may use a timing signal (e.g., respiratory phase signal) generated byPTD20; however one skilled in the art will readily recognize other techniques for deriving a timing signal that correlate to at least one of the cardiac or respiratory cycle or other anatomical cycle of the patient.
• As described above, the indicia indicate the location ofsteerable catheter600 andpercutaneous needle650 based on the location oflocalization elements610,660 tracked bynavigation system70 assteerable catheter600 andpercutaneous needle650 are navigated by the physician or other healthcare profession on and/or withinpatient10. Rather than display the indicia on a real-time basis, the display of the indicia may be periodically updated based on the timing signal fromPTD20. In various embodiments,PTD20 may be connected tonavigation system70.Navigation system70 may then tracklocalization elements610,660 in response to a timing signal received fromPTD20. The position of the indicia may then be updated ondisplay80. It is readily understood that other techniques for synchronizing the display of an indicia based on the timing signal are within the scope of the present invention, thereby eliminating any flutter or jitter which may appear on the displayed image(s). It is also envisioned that a path (or projected path) ofsteerable catheter600,percutaneous needle650, and/or other medical devices may also be illustrated on the displayed image(s).
• Utilizing the devices, systems, and/or methods described herein, a method of endobronchially confirming the location of a target in the lung of a patient and percutaneously intercepting the target at the confirmed location may be performed. In various embodiments, this method is performed during a second time interval after animage dataset400 is generated during a first time interval. As illustrated inFIGS. 20A-20B, an embodiment of a method of endobronchially confirming the location of a target is illustrated. Atstep1000,PTD20 is affixed to the external surface of apatient10. Atstep1002, the respiratory state ofpatient10 may be monitored by tracking the location ofPTD20 usingnavigation system70. Atstep1004,navigation system70 displays an image fromimage dataset400 ondisplay80 as a function of the monitored respiratory state. The displayed image is selected from one or more images inimage dataset400 and/or is generated bynavigation system70 using one or more images inimage dataset400. The displayed image is registered toPTD20. Atstep1006, an initial location of one or more target tissues inimage dataset400 is determined. This initial location of the target tissue is where it is believed that a target tissue is located withinpatient10.
• In certain embodiments, for example, the initial location of the target tissue(s) is determined afterimage dataset400 is generated during the first time interval. In certain embodiments, for example, the initial location of the target tissue(s) may be selected at the start of and/or during the second time interval. The initial location of the target tissue(s) may be determined automatically using nodule detection or segmentation algorithms carried out byprocessor52 ofimage analysis system50 and/orprocessor72 ofnavigation system70. Additionally or alternatively, a physician or other healthcare professional manually identifies a target tissue on an image displayed ondisplay60 ofimage analysis system50 and/ordisplay80 ofnavigation system70. The physician or other healthcare professional may then determine the initial location of the target tissue(s) by selecting the target tissue depicted on display(s)50,80 using user interface device(s)64,84 (e.g., by clicking on displayed target tissue with a mouse) or some other point selection tool. In other embodiments, the initial location of the target tissue may be determined by the physician or other healthcare professional using nodule segmentation tools and/or using nodule density information. Anindicia720 of the initial target tissue location may then be displayed ondisplay80 as shown inFIG. 14.
• Returning toFIG. 20A, atstep1008, a physician or other healthcare professional navigatessteerable catheter600 through the airway ofpatient10 to a position proximate the initial location of the target tissue. Additionally, in certain embodiments, animaging device633 such as bronchoscopic video camera630 (seeFIG. 12A) is inserted into workingchannel608,navigation system70 displays ondisplay80 the real-time image feed of the inside of the airway ofpatient10 generated bybronchoscopic video camera630 as shown inpanel716 ofFIG. 14. As described above the real-time image feed may be registered tosteerable catheter600. In certain embodiments,navigation system70 mayoverlay navigation pathway416 onto the real-time image feed frombronchoscopic video camera630. In other embodiments, for example, navigation system may also overlay directional cues such as arrows or other indicators on the real-time image feed frombronchoscopic video camera630. Integrating navigational aids, including but not limited tonavigation pathway416 and/or directional cues, with the real-time image feed may assist the physician or other healthcare professional in navigatingsteerable catheter600 to the desired target tissue. Accordingly, in certain embodiments wherein navigational aids are overlaid onto real-time image feed, a virtual volumetric scene does not need to be displayed ondisplay80 ofnavigation system70.
• With reference again toFIG. 20A, assteerable catheter600 is navigated through the airway ofpatient10, atstep1010,navigation system70 tracks the location oflocalization element610 ofsteerable catheter60. As described above, an indicia of718 of the location ofsteerable catheter600 may also be displayed ondisplay80 as shown inpanels700,702,704, and706 ofFIG. 14.
• Referring now toFIG. 20B, the method continues atstep1012, where information regarding the presence of the target tissue is generated usingtissue sensing device632 inserted into workingchannel608 ofsteerable catheter600. In certain embodiments,tissue sensing device632 may be imagingdevice633 inserted into the airway ofpatient10, such as, for example, endobronchial ultrasound (EBUS) device634 (seeFIG. 12B), an optical coherence tomography device (OCT), and/or probe based Confocal Laser Endomicroscopy (pCLE).Imaging device633 may be extended outtip607 ofsteerable catheter600 and may generate a population of images of the target tissue. Where imaging device637 isEBUS device634,EBUS device634 may be a radial EBUS device or a linear EBUS device. Illustrated inFIG. 21 is anexemplary image721 of the target tissue generated by a radial EBUS device which may be displayed ondisplay80. In other embodiments,tissue sensing device632 may include, but is not limited to, a cell analysis device, a cancer detecting device, an exhaled breath condensate analyzer, a physiological characteristic sensor, a chemical analysis device, an aromatic hydrocarbon detection device, etc.
• Returning toFIG. 20B, a confirmed location of the target is using the generated information regarding the presence of the target tissue and the tracked location oflocalization element610 ofsteerable catheter600. For example, iftissue sensing device632 is animaging device633 which generates a population of images of the target tissue,navigation system70 tracks the extension (x), if any, ofimaging device633 in relation tolocalization element610. By tracking the extension (x) in relation tolocalization element610 and the position and orientation (POSE) oflocalization element610,navigation system70 knows the coordinates at which the population of images of the target tissue are generated and may thus determine the actual location and size of the target tissue withinpatient10. In certain embodiments, the confirmed location of the target tissue is determined in relation to the location ofPTD20. In other embodiments, for example, the confirmed location of the target tissue is determined in relation to the location of electromagnetic (EM) field generator82 ofnavigation system70.
• Atstep1016, after the confirmed location of the target tissue is determined, the confirmed location of the target tissue is recorded. In one embodiment, for example, recording the confirmed location of the target tissue comprises recording a three-dimensional (3D) location of the confirmed target tissue in relation toPTD20. In another embodiment, for example, recording the confirmed location of the target tissue comprises recording a three-dimensional (3D) location of the confirmed target tissue in relation to electromagnetic (EM) field generator82 ofnavigation system70. In one embodiment, for example, recording the confirmed location of the target tissue comprises recording four-dimensional data (4D) comprising a three-dimensional (3D) location of the confirmed target tissue in relation toPTD20 and the respiratory state ofpatient10 at the time the location of the target tissue was confirmed. In another embodiment, for example, recording the confirmed location of the target tissue comprises recording four-dimensional data (4D) comprising a three-dimensional (3D) location of the confirmed target tissue in relation to electromagnetic (EM) field generator82 ofnavigation system70 and the respiratory state ofpatient10 at the time the location of the target tissue was confirmed. In yet another embodiment, for example, recording the confirmed location of the target tissue comprises recording four-dimensional (4D) data comprising a three-dimensional location (3D) of the confirmed target tissue in relation toPTD20 and a cardiac state of the patient at the time the location of the target tissue was confirmed. In yet another embodiment, for example, recording the confirmed location of the target tissue comprises recording four-dimensional (4D) data comprising a three-dimensional location (3D) of the confirmed target tissue in relation to electromagnetic (EM) field generator82 and a cardiac state of the patient at the time the location of the target tissue was confirmed. In various embodiments, this confirmed location of the target tissue may then be applied to one or more images fromimage dataset400 depicting the airway at the respiratory state ofpatient10 at the time the location of the target tissue was confirmed. This information is recorded inmemory component74 ofnavigation system70.
• Atstep1018, the confirmed location of the target tissue is displayed ondisplay80 ofnavigation system70 in one or more images fromimage dataset400. In certain embodiments, the displayed image(s) depict the airway of the patient at the respiratory state ofpatient10 at the time the location of the target tissue was confirmed. As shown inFIG. 22,navigation system70 may display an indicia722 (shown as crosshair bounded by a square) of the confirmed location of the target tissue in a variety of images, including but not limited to, hybrid “Inspiration-Expiration”3D airway model414 inpanel700, axial, coronal and oblique images inpanels702,704 (shown enlarged inFIG. 22A), and706, respectively, and virtual volumetric scene inpanel712.Navigation system70 may be able to display an indicia720 (shown as circle in crosshair bounded by a circle) of the initial location of the target tissue, anindicia722 of the confirmed location of the target tissue, and an indicia718 (shown as crosshair) ofsteerable catheter600. The method may optionally continue according to steps illustrated inFIGS. 20C and 20E as described more fully elsewhere herein.
• After the confirmed location of the target tissue is recorded, the physician or other healthcare professional can return to the confirmed location of the target tissue using a medical device, such assteerable catheter600 orpercutaneous needle650, without needing to re-register the patient. Accordingly, because, in certain embodiments, the confirmed location of the target tissue is recorded in relation to the location ofpatient tracking device20, the physician or other healthcare professional can navigate medical device to the confirmed location of the target tissue knowing the location ofpatient tracking device20. For example, in certain embodiments, the physician or other healthcare professional navigates to the confirmed location of the target tissue whereinnavigation system70 displays ondisplay80 only anindicia722 of the confirmed location of the target tissue, anindicia718 ofsteerable catheter600, and/or anindicia734 of percutaneous needle650 (seeFIG. 23). Using one or more ofindicia722,718,734, physician or other healthcare professional navigates medical device to the confirmed location of the target tissue without needingnavigation system70 to display hybrid “Inspiration-Expiration”3D airway model414, one or more images fromimage dataset400,navigation pathway416, and/or real time image feed frombronchoscopic video camera630.
• Additionally, because, in certain embodiments, the confirmed location of the target tissue is recorded in relation to the location of electromagnetic (EM) field generator82, the physician or other healthcare professional can navigate medical device to the confirmed location of the target tissue ifpatient10 has not moved relative to localization device76. For example, in certain embodiments, the physician or other healthcare professional navigates to the confirmed location of the target tissue whereinnavigation system70 displays ondisplay80 anindicia722 of the confirmed location of the target tissue, anindicia718 ofsteerable catheter600, and/or anindicia734 ofpercutaneous needle650. Using one or more ofindicia722,718,734, physician or other healthcare professional navigates medical device to the confirmed location of the target tissue without needingnavigation system70 to display hybrid “Inspiration-Expiration” 3D airway model, one or more images fromimage dataset400,navigation pathway416, and/or real time image feed frombronchoscopic video camera630.
• Due to a variety of factors including, but not limited to, registration errors, shifting of patient location, changes in patient anatomy, the initial target location determined atstep1006 may not match the actual confirmed location of the target determined instep1014. Accordingly, without performing this confirmation step, a biopsy or medical therapy delivered to the initial target location may only partially intercept the actual target tissue or may be performed at an incorrect location such as healthy tissue. Insufficient and/or incorrect sampling or treatment of the target tissue and/or healthy tissue may lead to misdiagnoses and/or reduced treatment efficacy. Thus, by confirming the actual location of the target tissue in relation toPTD20 and/or electromagnetic (EM) field generator82, intercepting (e.g., sampling, treating) the target tissue may be more accurately carried out in a variety of ways. Consequently, a physician or other healthcare professional may have a higher confidence that they are intercepting the target tissue. In certain embodiments, for example, the target tissue may be sampled using a variety of medical devices including, but not limited to, forceps devices, needles, brushes, etc. Treatment may also be endobronchially delivered to the confirmed location of the target tissue using a variety of medical devices including, but not limited to, ablation probes, radioactive seeds, implants, energy delivery devices, therapy delivery devices, delivery of energy activated substances (e.g., porfimer sodium) and energy devices, radiofrequency (RF) energy devices, cryotherapy devices, laser devices, microwave devices, diffuse infrared laser devices, fluids, drugs, combinations thereof, or the like.
• In certain embodiments, the target tissue may not be reachable using endobronchial methods, accordingly, after the location of the target tissue is endobronchially confirmed, the target tissue may be percutaneously intercepted. The percutaneous interception may be carried out using a percutaneous device. Percutaneous device may preferably bepercutaneous needle650 described above. Becausepercutaneous needle650 includeslocalization element660, the position and orientation (POSE) oftip657 is tracked bynavigation system70. Accordingly,navigation system70 calculates and displays a trajectory ofpercutaneous needle650 based on wherepercutaneous needle650 is located and oriented by physician or other healthcare professional. However, in various embodiments, for example, percutaneous device may include, but is not limited topercutaneous needle650, a thoracic wedge resection device, a biopsy gun, a tracked core biopsy device, and/or any other medical device which may be used to percutaneously intercept a target tissue. The percutaneous devices preferably include a localization element so that the position and orientation (POSE) of the percutaneous devices may be tracked bynavigation system70.
• Referring now toFIG. 20C, atstep1020,navigation system70 displays ondisplay80 one or more trajectories from an entry point on the surface ofpatient10 to the confirmed location of the target tissue. In certain embodiments, a displayed trajectory may be a suggested trajectory calculated bynavigation system70 wherein the suggested trajectory is the shortest distance from the confirmed location of the target tissue to the external surface ofpatient10.Navigation system70 may utilize procedural position ofpatient10 such as supine, prone, or laying on the left or right side to calculate the suggested trajectory. Accordingly,navigation system70 may display a suggested trajectory that does not require altering the procedural position ofpatient10. For example, if the trajectory having the shortest distance from the confirmed location of the target tissue to the external surface ofpatient10 requires entry through the back ofpatient10, butpatient10 is supine, an alternative suggested trajectory may be calculated and displayed which permits entry through the chest or side ofpatient10.
• In certain embodiments, the suggested trajectory may be calculated that extends through the longest axis or longest diameter of the target tissue to ensure that the amount of target tissue sampled and/or treated is increased and/or maximized. Additionally, the patient10 specific segmented target tissue may also have characteristics such as high density or spiculations that identify preferred regions to sample and/or treat. For example, in certain embodiments, the suggested trajectory may be calculated to extend through spiculations of the target tissue. In other embodiments, for example, a change in size of the target tissue may be seen between inspiration and expiration scans. In certain situations, this apparent change in size may be the result of infected tissue near the target tissue changing in size from inspiration to expiration. Typically, however, the target tissue will not change in size from inspiration to expiration, accordingly imageanalysis system50 and/ornavigation system70 may be able to identify the target tissue based on a minimal or no change in density, size, location, and shape from inspiration to expiration. The suggested trajectory may thus be calculated to extend through such portions of the target tissue.
• Additionally or alternatively, in certain embodiments, a displayed trajectory may be an actual trajectory calculated bynavigation system70 wherein the actual trajectory is the based on wherepercutaneous needle650 is located and oriented by physician or other healthcare professional. Accordingly, in certain embodiments,navigation system70 may be able to display ondisplay80 both a suggested trajectory and an actual trajectory ofpercutaneous needle650. Thus, a physician or other healthcare professional may movetip657 ofpercutaneous needle650 along the body ofpatient10 and may orientpercutaneous needle650 so that the suggested trajectory and the actual trajectory displayed bynavigation system70 ondisplay80 are in alignment. Once the actual trajectory and the suggested trajectory are in alignment, the physician or other healthcare professional insertspercutaneous needle650 into patient along the actual trajectory. In other embodiments, for example, no suggested trajectory may be displayed.
• FIG. 23 illustrates one embodiment wherenavigation system70 displays ondisplay80 suggested and actual trajectories from an entry point on the surface ofpatient10 to the confirmed location of the target tissue.Panels724 and726 illustrate views thatnavigation system70 may display. The displayed images may be selected from one or more images inimage dataset400 or may be generated bynavigation system70 using one or more images inimage dataset400. Additionally, indicia722 (shown as crosshair bounded by a square) of the confirmed location of the target tissue and suggestedtrajectory730 fromentry point732 to the confirmed location of the target tissue are displayed ondisplay80. Furthermore, anindicia734 of the location ofpercutaneous needle650 is displayed. In certain embodiments, for example,indicia734 indicates the location ofdistal end portion656 ofpercutaneous needle650. In other embodiments, for example,indicia734 indicates the location oflocalization element660 ofpercutaneous needle650. In yet other embodiments, for example,indicia734 indicates the location oftip657 ofpercutaneous needle650. Anactual trajectory736 ofpercutaneous needle650 is also displayed ondisplay80 bynavigation system70 as shown inpanels724,726. As described more fully elsewhere herein, suggestedtrajectory730 may avoidanatomical structures740 such as, for example, bone, the heart, the liver, other organs, fissures, diseased tissue, such as chronic obstructive pulmonary disease (COPD) lung tissue, and blood vessels. Furthermore, as shown inpanel724,navigation system70 may be able to display a distance fromtip657 ofpercutaneous needle650 to the confirmed location of the target tissue.
• Referring again toFIG. 20C, atstep1022, the physician or other healthcare professional insertspercutaneous needle650 into the patient and navigatestip657 proximate to the confirmed location of the target tissue. Then atstep1024, the target tissue at the confirmed location is intercepted. In certain embodiments, for example, intercepting the target tissue at the confirmed location includes inserting a biopsy device into workingchannel658 ofpercutaneous needle650 and extending the biopsy device beyondtip657 to sample the target tissue. In other embodiments, for example, intercepting the target tissue at the confirmed location includes inserting a therapy device into workingchannel658 ofpercutaneous needle650 and delivering therapy to the target tissue. In various embodiments, therapy device may be an ablation probe andnavigation system70 may be able to display ondisplay80 ablation models at the confirmed location of the target tissue. The ablation models may assist the physician or other healthcare professional in delivering the appropriate amount of treatment to the target tissue. The method may optionally continue according to steps illustrated inFIG. 20D as described more fully elsewhere herein.
• In various embodiments, the method as described inFIGS. 20A-20C may further include the step of taking a population of images of at least a portion ofpercutaneous needle650 at the confirmed location of the target tissue usingimaging device633 disposed in the airway of the patient. For example, as described above,imaging device633 may beEBUS device634 extended outtip607 ofsteerable catheter600. The images may be used to confirm thattip657 ofpercutaneous needle650 was actually navigated to proximate the confirmed location of the target tissue. The image(s) ofpercutaneous needle650 at the confirmed location of the target tissue may be recorded into a patient file as proof that the confirmed location of the target was reached. Additionally,imaging device633 may be used to generate a population of images of the biopsy device sampling the target tissue and/or a population of images of the therapy device delivering therapy to the target tissue. The image(s) of biopsy device and therapy device sampling or delivering therapy to the target tissue may be recorded into a patient file as proof that the target tissue was sampled and/or treated.
• Additional to or alternative to usingimaging device633 to evaluate whetherpercutaneous needle650 has been navigated to proximate the confirmed location of the target tissue, a sensing device may be used to sense the presence of at least a portion ofpercutaneous needle650 at the confirmed location of the target tissue. For example, the sensing device may include, but is not limited to, a heat sensor, magnetic sensor, electrical sensor, that may be extended outtip607 ofsteerable catheter600. In certain embodiments, the sensing device may also be able to sense the presence of the biopsy device sampling the target tissue and/or the therapy device delivering therapy to the target tissue. For example, a heat sensor extended outtip607 ofsteerable catheter600 may be used to determine when the target tissue has been sufficiently treated. Additionally, navigatingsteerable catheter600 down multiple airways adjacent to a target tissue and extending a heat sensor outtip607 ofsteerable catheter600 in each of the adjacent airways may be used to determine when a target tissue that is located between the adjacent airways has been treated. In certain embodiments, heat sensors may be placed in multiple airways adjacent to a target tissue usingsteerable catheter600 and the multiple heat sensors may be used to determine when a target tissue that is located between the adjacent airways has been treated.
• In various embodiments, the method as described inFIGS. 20A-20C may further include the steps outlined inFIG. 20D. Atstep1026, usingimaging device633 disposed in the airway ofpatient10, a population of images are generated of one or more anatomical structures proximate the confirmed location of the target tissue. Anatomical structures may include, but are not limited to, bone, the heart, the liver, other organs, fissures, diseased tissue, such as, for example chronic obstructive pulmonary disease (COPD) lung tissue, and blood vessels. Accordingly, the anatomical structures may be any structure within the body ofpatient10 that should be avoided, if possible, bypercutaneous needle650. The imaging device, for example, may beEBUS device634 extended outtip607 ofsteerable catheter600. Atstep1028, a confirmed location of the anatomical structure(s) is determined in relation to the location ofPTD20 using the population of images and the tracked location oflocalization element610 ofsteerable catheter600. For example,navigation system70 tracks the extension (x), if any, ofEBUS device634 in relation tolocalization element610. By tracking the extension (x) in relation tolocalization element610,navigation system70 knows the coordinates at which the population of images of the anatomical structure(s) are generated and may thus determine the actual location and size of the anatomical structure(s) withinpatient10 with respect toPTD20.
• Atstep1030, after the location of the anatomical structure(s) is determined, the confirmed location of the anatomical structure(s) is recorded. In one embodiment, for example, recording the confirmed location of the anatomical structure(s) comprises recording a three-dimensional (3D) location of the confirmed anatomical structure(s) in relation toPTD20. In another embodiment, for example, recording the confirmed location of the anatomical structure(s) comprises recording a three-dimensional (3D) location of the confirmed anatomical structure(s) in relation to electromagnetic (EM) field generator82 ofnavigation system70. In one embodiment, for example, recording the confirmed location of the anatomical structure(s) comprises recording four-dimensional data (4D) comprising a three-dimensional (3D) location of the confirmed anatomical structure(s) in relation toPTD20 and the respiratory state ofpatient10 at the time the location of the anatomical structure(s) was confirmed. In another embodiment, for example, recording the confirmed location of the anatomical structure(s) comprises recording four-dimensional data (4D) comprising a three-dimensional (3D) location of the confirmed anatomical structure(s) in relation to electromagnetic (EM) field generator82 ofnavigation system70 and the respiratory state ofpatient10 at the time the location of the anatomical structure(s) was confirmed. In yet another embodiment, for example, recording the confirmed location of the anatomical structure(s) comprises recording four-dimensional (4D) data comprising a three-dimensional location (3D) of the confirmed anatomical structure(s) in relation toPTD20 and a cardiac state of the patient at the time the location of the anatomical structure(s) was confirmed. In yet another embodiment, for example, recording the confirmed location of the anatomical structure(s) comprises recording four-dimensional (4D) data comprising a three-dimensional location (3D) of the confirmed anatomical structure(s) in relation to electromagnetic (EM) field generator82 and a cardiac state of the patient at the time the location of the anatomical structure(s) was confirmed. In various embodiments, this confirmed location of the anatomical structure(s) may then be applied to one or more images fromimage dataset400 depicting the airway at the respiratory state ofpatient10 at the time the location of the anatomical structure(s) was confirmed. This information is recorded inmemory component74 ofnavigation system70.
• Optionally, atstep1032,navigation system70 calculates and displays a trajectory of a percutaneous device (e.g., percutaneous needle650) from the confirmed location of the target tissue to a corresponding entry point on the body ofpatient10. This trajectory may avoid some or all of the anatomical structures. Accordingly, if a physician or other healthcare professional inserts percutaneous device, such aspercutaneous needle650, following this trajectory, the percutaneous device may avoid some or all of the anatomical structures thereby preventing damage to the anatomical structure(s).
• In various embodiments, in addition to calculating and/or displaying any of the trajectories described herein,navigation system70 displays an extended trajectory of a medical device that may be inserted into workingchannel658 ofpercutaneous needle650 and extendedpast tip657. In certain embodiments, for example, the medical device may include, but is not limited to, an aspiration needle, a forceps device, a brush, or any type of biopsy device. In other embodiments, for example, the medical device may include, but is not limited to, an ablation probe, a radioactive seed placement device, a fiducial placement device, and/or any type of therapy device. The extended trajectory displays the potential extension of the medical device so that it may be confirmed that potential extension of the medical device will sample and/or treat the target tissue and will not hit one or more anatomical structures. The displayed extended trajectory may also aid in ensuring that a sufficient sample is taken and/or that the treatment may be properly placed in the target tissue.
• In various embodiments, the method as described inFIGS. 20A-20B may further include the steps outlined inFIG. 20E. In addition to or alternative to generating images of anatomical structures ofpatient10 usingimaging device633 inserted into the airway ofpatient10, one or more atlas models are employed to assist the procedure during the second time interval. The atlas model(s) are three-dimensional models of human anatomy and therefore include a variety of anatomical structures. The anatomical structures may include, but are not limited to, bone, the heart, the liver, other organs, fissures, diseased tissue, such as, for example, chronic obstructive pulmonary disease (COPD) lung tissue, and blood vessels. Accordingly, the anatomical structures may be any structure within the body ofpatient10 that should be avoided, if possible, by percutaneous device (e.g., percutaneous needle650). Additionally, the atlas model(s) may include weighted information related to the acceptability of a planned trajectory or planned ablation procedure to determine the optimal plan. This weighted information may include, but is not limited to, information regarding which anatomical structure(s) cannot be crossed by a medical device, information regarding avoid anatomical structure(s) by at least a given distance, and information regarding the heat sink effect of anatomical structure(s) so that ablation location and amount may be adjusted.
• Thus as shown inFIG. 20E atstep1034, one or more atlas models is matched toimage dataset400 ofpatient10 wherein the matching may comprise deforming the atlas model(s) to theimage dataset400 and/or registering the atlas model(s) topatient10. Atstep1036,navigation system70 identifies anatomical structure(s) to be avoided by the trajectory of the percutaneous device. Atstep1038,navigation system70 may calculate and display a trajectory of the percutaneous device from the confirmed location of the target tissue to a corresponding entry point on the body ofpatient10. This trajectory may avoid some or all of the anatomical structures. Accordingly, if a physician or other healthcare professional inserts percutaneous device, such aspercutaneous needle650, following this trajectory, percutaneous device may avoid some or all of the anatomical structures thereby preventing damage to the anatomical structure(s). Following the steps outlined inFIG. 20E, the method may optionally further include the steps illustrated inFIG. 20C.
• In any of the embodiments of the methods described herein, a dye may be injected into the target tissue at the confirmed location using a needle inserted into workingchannel608 ofsteerable catheter600 or using a needle inserted into workingchannel658 ofpercutaneous needle650. Thus, when sampling the target tissue using a medical device inserted into workingchannel658 ofpercutaneous needle650, the presence of dye in the sample provides another indication that the correct target tissue was sampled. These additional steps may be helpful, for example, in lung resections where there is significant movement of the lungs ofpatient10. For example, during lung resections there may be a gap between the chest wall and the lung and the physician or other healthcare profession may use a rigid scope to enter intopatient10. Because the confirmed target tissue was previously dyed using a needle inserted into workingchannel608 ofsteerable catheter600 or using a needle inserted into workingchannel658 ofpercutaneous needle650, the physician or other healthcare professional may be able to visually see the dye. This may assist the physician or healthcare professional in sampling and/or treating the correct target tissue.
• Additionally, in various embodiments of the methods described herein, aftertip607 ofsteerable catheter600 has been navigated proximate confirmed location of target tissue a sample of air proximate the confirmed location of the target tissue may be taken. Then cells, scents or other potential indicators of cancer within the air sample may then be analyzed to determine if the target tissue is cancerous. In certain embodiments, a breath analysis device may be inserted into workingchannel608 ofsteerable catheter600 and this breath analysis device may sample the air in situ. In other embodiments, a vacuum of air may be drawn on workingchannel608 fromport616 to sample the air proximate the confirmed location of the target tissue may be taken. The vacuum may be created by a syringe inserted intoport616 or by some other suction device known in the art. In yet other embodiments, a sample of air proximate an airway segment near the confirmed location of the target tissue may be taken instead of, or in addition to, the sample taken proximate the confirmed location of the target.
• Furthermore, in any of the embodiments of the methods described herein,navigation system70 may be able to control a robotic medical device having a percutaneous needle.Navigation system70 may be able to cause robotic medical device to navigate a percutaneous needle to the calculated entry point on the surface ofpatient10. The percutaneous needle may then be inserted intopatient10 at the calculated entry point on the surface ofpatient10 and the percutaneous needle may be extended to the confirmed location along the calculated trajectory. Thus, a robotic medical device may use information fromnavigation system70 to perform any of the methods described herein.
• The accompanying Figures and this description depict and describe certain embodiments of a navigation system (and related methods and devices) in accordance with the present invention, and features and components thereof. It should also be noted that any references herein to front and back, right and left, top and bottom and upper and lower are intended for convenience of description, not to limit the present invention or its components to any one positional or spatial orientation.
• It is noted that the terms “comprise” (and any form of comprise, such as “comprises” and “comprising”), “have” (and any form of have, such as “has” and “having”), “contain” (and any form of contain, such as “contains” and “containing”), and “include” (and any form of include, such as “includes” and “including”) are open-ended linking verbs. Thus, a method, an apparatus, or a system that “comprises,” “has,” “contains,” or “includes” one or more items possesses at least those one or more items, but is not limited to possessing only those one or more items. Individual elements or steps of the present methods, apparatuses, and systems are to be treated in the same manner.
• The terms “a” and “an” are defined as one or more than one. The term “another” is defined as at least a second or more. The term “coupled” encompasses both direct and indirect connections, and is not limited to mechanical connections.
• Those of skill in the art will appreciate that in the detailed description above, certain well known components and assembly techniques have been omitted so that the present methods, apparatuses, and systems are not obscured in unnecessary detail.
• While various embodiments of the invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. Thus, the breadth and scope of the invention should not be limited by any of the above-described embodiments, but should be defined only in accordance with the following claims and their equivalents.
• The previous description of the embodiments is provided to enable any person skilled in the art to make or use the invention. While the invention has been particularly shown and described with reference to embodiments thereof, it will be understood by those skilled in art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. For example, the patient tracking device, steerable catheter, percutaneous needle, and localization elements may be constructed from any suitable material, and may be a variety of different shapes and sizes, not necessarily specifically illustrated, while still remaining within the scope of the invention.

Claims (11)

1. A method of registering a real-time image feed from an imaging device inserted into a steerable catheter using a navigation system comprising a display, wherein the steerable catheter comprises an elongate flexible shaft having a proximal end portion, a distal end portion terminating in a tip, a working channel extending therebetween, and a handle attached to the proximal end portion of the flexible shaft, the method comprising:

inserting the imaging device into the working channel of the steerable catheter;

generating a real-time image feed of one or more reference points, wherein the orientation of the reference points is known;

orienting the handle of the steerable catheter to a neutral position;

displaying the real-time image feed on the display; and

registering the real-time image feed to the steerable catheter by rotating the displayed image so that the reference points in the real-time image feed are matched to the known orientation of the reference points.

2. The method ofclaim 1 further comprising correcting image distortion in the real-time image feed.

3. The method ofclaim 1 further comprising navigating the steerable catheter into the airway of the patient and wherein the reference points comprise anatomical features of the airway of the patient.

4. The method ofclaim 1, further comprising confirming the alignment of the real time image feed, comprising the steps of:

steering the steerable catheter in a first direction;

observing that the displayed real-time image feed moves in the first direction.

5. The method ofclaim 3, wherein the navigation system further comprises a localization device and is adapted to display a virtual volumetric scene of the airway on the display of the navigation system, and wherein the steerable catheter further comprises a localization element proximate the distal end portion of the elongate flexible shaft, wherein the method further comprises:

tracking the location of the localization element of the steerable catheter in the airway using the navigation system;

determining an orientation of the registered real-time image feed with respect to the tracked location of the localization element of the steerable catheter;

recording the orientation of the registered real-time image feed with respect to the tracked location of the localization element of the steerable catheter.

6. The method ofclaim 5 further comprising overlaying one or more navigational aids onto the real-time image feed, wherein the navigational aids are registered to the real-time image feed.

7. The method ofclaim 6 wherein the navigational aids comprise one or more of a navigation pathway and a directional cue.

8. The method ofclaim 5 further comprising:

displaying a virtual volumetric scene of the airway on the display of the navigation system; and

registering the virtual volumetric scene to the real-time image feed.

9. The method ofclaim 8 further comprising maintaining registration of the virtual volumetric scene to the real time image feed as the steerable catheter is navigated through the airway of the patient.

10. The method ofclaim 8 further comprising overlaying one or more navigational aids onto the real-time image feed.

11. The method ofclaim 10 wherein the navigational aids comprise one or more of a navigation pathway and a directional cue.

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