Patent Description:
Minimally invasive medical techniques are intended to reduce the amount of tissue that is damaged during medical procedures, thereby reducing patient recovery time, discomfort, and harmful side effects. Such minimally invasive techniques may be performed through natural orifices in a patient anatomy or through one or more surgical incisions. Through these natural orifices or incisions, an operator may insert minimally invasive medical tools to reach a target tissue location. Minimally invasive medical tools include instruments such as therapeutic, diagnostic, biopsy, and surgical instruments. Minimally invasive medical tools may also include imaging instruments such as endoscopic instruments. Imaging instruments provide a user with a field of view within the patient anatomy. Some minimally invasive medical tools and imaging instruments may be teleoperated or otherwise computer-assisted.

Document <CIT>may be considered to disclose a medical system comprising: an elongate device; an elongate sheath configured to extend within the elongate device, the elongate sheath including an identification feature; an imaging probe configured to extend within the elongate sheath; and a control system configured to: receive imaging data from the imaging probe, the imaging data being captured by the imaging probe; analyze the imaging data to identify an appearance of the identification feature within the imaging data.

Various features may improve the effectiveness of minimally invasive imaging instruments including coupling members that allow controlled movement and temporary storage systems for use during a medical procedure. The following presents a simplified summary of various examples described herein and is not intended to identify key or critical elements or to delineate the scope of the claims.

Consistent with some examples, a medical system is provided. The medical system includes an elongate device, an elongate sheath configured to extend within the elongate device, and an imaging probe configured to extend within the elongate sheath. The elongate sheath includes an identification feature. The medical system further includes a control system configured to receive imaging data from the imaging probe. The imaging data is captured by the imaging probe. The control system is further configured to analyze the imaging data to identify an appearance of the identification feature within the imaging data. The control system is further configured to, based on the appearance of the identification feature, register the imaging data to a reference frame of the elongate device.

Consistent with some examples, a method is provided. The method includes receiving imaging data from an imaging probe. The imaging data is captured by the imaging probe, and the imaging probe is configured to extend within an elongate sheath. The elongate sheath is configured to extend within an elongate device, and the elongate sheath includes an identification feature. The method further includes analyzing the imaging data to identify an appearance of the identification feature within the imaging data. The method further includes, based on the appearance of the identification feature, registering the imaging data to a reference frame of the elongate device.

Other examples include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods.

It is to be understood that both the foregoing general description and the following detailed description are illustrative and explanatory in nature and are intended to provide an understanding of the various examples described herein without limiting the scope of the various examples described herein. In that regard, additional aspects, features, and advantages of the various examples described herein will be apparent to one skilled in the art from the following detailed description.

Various examples described herein and their advantages are described in the detailed description that follows. It should be appreciated that like reference numerals are used to identify like elements illustrated in one or more of the figures for purposes of illustrating but not limiting the various examples described herein.

The techniques disclosed in this document may be used to register intraoperative image data (which may be referred to as intraoperative imaging data), such as endobronchial ultrasound (EBUS), radial endobronchial ultrasound (REBUS), and/or fluoroscopic imaging data to a medical instrument reference frame during a medical procedure. In some examples, the image data produced by one or more intraoperative imaging devices may be utilized to refine locations of an instrument, an anatomic structure, and/or a target in a model constructed from preoperative imaging. The intraoperative image data may be registered to a reference frame of a medical instrument to assist with determining a rotation, an insertion distance, and/or off-axis bending (e.g., pitch and/or yaw) of the intraoperative imaging device.

With reference to <FIG>, an image-guided medical procedure, which may be robotic-assisted or otherwise teleoperated, may be conducted in which a display system <NUM> may display a virtual navigation image <NUM>, which includes an image reference frame (XI, YI, ZI) <NUM>. An elongate device, such as a medical instrument <NUM>, may be registered (e.g., dynamically referenced) with an anatomic model <NUM> of a patient derived from preoperative image data obtained, for example, from a computerized tomography (CT) scan. The anatomic model <NUM> may include a target <NUM>, such as a lesion or nodule of interest, which the procedure is intended to address (e.g., biopsy, treat, view). In some examples, the virtual navigation image <NUM> may present a physician with a virtual image of the internal surgical site from a viewpoint of the medical instrument <NUM>, such as from a distal tip of the medical instrument <NUM>. In some examples, the display system <NUM> may present a real-time view from the distal tip of the medical instrument <NUM>, such as when the medical instrument <NUM> includes an endoscope. In some examples, the medical instrument <NUM> may be manipulated by a robotic-assisted manipulator controlled by a control system <NUM>, or processing system, which includes one or more processors. An example of a robotic-assisted medical system will be described further at <FIG>. In some examples, an imaging probe may extend through a lumen of the medical instrument <NUM>.

Generating the virtual navigation image <NUM> involves the registration of the image reference frame (XI, YI, ZI) <NUM> to a surgical reference frame (e.g., frame XS, YS, ZS of <FIG>) of the anatomy and/or a medical instrument reference frame (e.g., frame XM, YM, ZM of <FIG>) of the medical instrument <NUM>. This registration may rotate, translate, or otherwise manipulate, by rigid or non-rigid transforms, points associated with the segmented instrument shape from the image data and/or points associated with the shape data from a shape sensor disposed along a length of the medical instrument <NUM>. This registration between the image and instrument reference frames may be achieved, for example, by using a point-based iterative closest point (ICP) technique as described in <CIT>, entitled "Systems and Methods of Registration for Image-Guided Surgery" and in <CIT>, entitled "Systems and Methods of Registration for Image-Guided Surgery,". The registration may be achieved additionally or alternatively by another point cloud registration technique.

As shown in <FIG>, an endotracheal (ET) tube <NUM> may be used to introduce one or more medical instruments into the airways of a patient P. In order for the ET tube <NUM> to accommodate more than one medical instrument, a multi-port adaptor <NUM> may be used to align the medical instruments for insertion through the ET tube <NUM>. As shown, the adaptor <NUM> includes three insertion channels <NUM>, <NUM>, <NUM> for accepting three medical instruments <NUM>, <NUM>, <NUM>, respectively. Although <FIG> shows three insertion channels <NUM>-<NUM> and three medical instruments <NUM>-<NUM>, the adaptor <NUM> may optionally include one channel, two channels, or four or more channels. In some examples, each of the medical instruments <NUM>-<NUM> is an elongate instrument, such as the medical instrument <NUM> of <FIG>. In some examples, one or more of the medical instruments <NUM>-<NUM> may be received within a catheter <NUM>. The catheter <NUM> may be inserted through the ET tube <NUM> and may extend beyond a distal end <NUM> of the ET tube <NUM> into one or more passageways <NUM> (e.g., airways) of the patient P. Additional details regarding the ET tube <NUM> may be found in <CIT>, entitled "Systems and Methods of Integrated Real-Time Visualization,".

<FIG> illustrates a medical system <NUM> that may include an outer catheter <NUM> through which a working catheter <NUM>, and an imaging probe <NUM>, an inflation lumen <NUM>, and an evacuation lumen <NUM> may extend. The outer catheter <NUM> may represent the catheter <NUM> of <FIG>. As shown in <FIG>, a distal end <NUM> of the outer catheter <NUM> has been inserted into anatomical passageways <NUM>, which may be the passageways <NUM>, of the patient P. In some examples, the inflation lumen <NUM> may be used to inflate one or more sealing devices, such as a balloon, to create a seal across one of the passageways <NUM>. The evacuation lumen <NUM> may be used for removing air from the passageways <NUM> that are distal to any sealing devices that may be within the passageways <NUM>. The outer catheter <NUM> may include a working lumen <NUM> through which the working catheter <NUM> is inserted. The outer catheter <NUM> may include an imaging lumen <NUM> through which the imaging probe <NUM> may be inserted. Alternatively, the imaging probe <NUM> may be inserted through the working catheter <NUM>. The working catheter <NUM> and/or the imaging probe <NUM> may represent one or more of the medical instruments <NUM>-<NUM> of <FIG>.

In some examples, the imaging probe <NUM> may be positioned within an imaging probe sheath <NUM>, which may additionally be inserted into the passageways <NUM> through the imaging lumen <NUM>. In some examples, the imaging probe <NUM> may be a radial probe, such as a radial endobronchial ultrasound (radial EBUS or REBUS) probe. The imaging probe <NUM> may include an imaging device <NUM> located near its distal end. The imaging device <NUM> may be a mechanical radial scanning device that is rotated about a longitudinal axis A of the imaging probe <NUM>. The imaging device <NUM> may obtain images in an imaging field of view <NUM>. In some examples, the field of view <NUM> represents a scanning direction of the imaging device <NUM>. In some examples, the scanning direction is a <NUM>° circumferential field of view that is perpendicular to the longitudinal axis A of the imaging probe <NUM>. The appearance of one or more objects in the field of view <NUM> may change as one or more of the position, orientation, and/or insertion distance of the imaging probe <NUM> changes. In some examples, the images captured by the imaging device <NUM> in the scanning direction are captured in a scan plane.

In some examples, the imaging device <NUM> may be an ultrasound transducer. The imaging device <NUM> may be coupled to one or more electrical wires or optical fibers for activating the ultrasound transducer, modulating its output, capturing return signals, and/or the like. In some examples, the imaging probe <NUM> may include side-facing transducers, forward-facing transducers, curved transducers, and/or the like. In some examples, the imaging probe <NUM> may include one or more electronically phased, mechanically scanned, and/or mechanically steerable transducer elements and/or arrays of transducer elements that are capable of capturing 2D, 3D, and/or 4D ultrasound images in proximity to the distal end of the imaging probe <NUM>.

As further shown in <FIG>, the medical system <NUM> may include a tool <NUM>, which may be inserted into the passageways <NUM> through the working catheter <NUM>. The tool <NUM> may extend beyond a distal end <NUM> of the working catheter <NUM>. The tool <NUM> may be a biopsy tool (e.g., a biopsy needle), an endoscopic instrument or other imaging device, an ultrasound probe, or any other medical tool. In some examples, the medical system <NUM> may include an external imaging device <NUM>, which may be an intraoperative external imaging device. The external imaging device <NUM> may be a fluoroscopy imaging device than generates intraoperative fluoroscopy image data, although any suitable imaging technique, such as conventional CT or cone beam CT ("CBCT") techniques, may be used without departing from the examples of the present disclosure.

As shown in <FIG>, the passageways <NUM> may be surrounded by tissue <NUM>. Located within the tissue <NUM> is a region of interest <NUM>, which may correspond to a lesion, a tumor, and/or any other anatomical target (e.g., the target <NUM> of <FIG>). Thus, the region of interest <NUM> may also be referred to herein as an anatomical target <NUM> or a target <NUM>. As shown in <FIG>, one or both of the working catheter <NUM> or the imaging probe <NUM> may be navigated within the passageways <NUM> to a location near the target <NUM>. For example, the outer catheter <NUM> may be steered to position the outer catheter <NUM> where desired within the passageways <NUM>. In some examples, the distal end <NUM> of the outer catheter <NUM> may be navigated to a deployment location near the target <NUM>. Navigation may be performed manually by a user with provided navigation guidance, automatically by the control system, or via a combination of both. As shown in <FIG>, the distal end <NUM> may be steered to orient the distal end <NUM> toward the target <NUM>.

In some examples, a position sensor system and/or a shape sensor <NUM> may extend within the outer catheter <NUM>. The shape sensor <NUM> may extend through the outer catheter <NUM> to the distal end <NUM> of the outer catheter <NUM>. In some examples, the shape sensor <NUM> may be used to register the outer catheter <NUM> to one or more preoperative or intraoperative images and/or models of the patient anatomy (e.g., the model <NUM> of <FIG>) and to provide real time localization of the outer catheter <NUM> to help guide the navigation of the outer catheter <NUM>. The shape sensor <NUM> may be a fiber optic shape sensor or any other position sensor. For example, the shape sensor <NUM> may be used to provide real-time shape data (e.g., information regarding a shape of the outer catheter <NUM> and/or a position of one or more points along the length of the outer catheter <NUM>). This shape data may be utilized to register the outer catheter <NUM> to the reference frame <NUM> of the preoperative image data (e.g., to the 3D model constructed from the preoperative image data) and to track a location of the outer catheter <NUM> during use. Additionally or alternatively, the reference frame <NUM> of the preoperative image data may be registered to a reference frame of the working catheter <NUM>. In some examples, the reference frame of the outer catheter <NUM> and the reference frame of the working catheter <NUM> are a common reference frame. The discussion above with respect to the navigation of the outer catheter <NUM> may also apply to navigation of the working catheter <NUM>.

In some examples, a position sensor system and/or a shape sensor (not shown) may extend within the imaging probe <NUM>. The shape sensor may extend through the imaging probe <NUM> to a distal end of the imaging probe <NUM>. Similar to the outer catheter <NUM> and the working catheter <NUM>, the shape sensor of the imaging probe <NUM> may be used to register the imaging probe <NUM> to the one or more preoperative or intraoperative images to provide real time localization of the imaging probe <NUM> to help guide the operator in positioning and/or orienting the imaging device <NUM> to take images of the target <NUM>. Additionally or alternatively, the imaging device <NUM> may capture images of the outer catheter <NUM>, the distal end <NUM>, the working catheter <NUM>, the sheath <NUM>, and/or one or more fiducial markers located on the outer catheter <NUM> and/or the sheath <NUM> to aid in registering the imaging probe <NUM> and/or localizing the imaging probe <NUM> relative to the target <NUM> and/or to the outer catheter <NUM>. Additional details regarding the outer catheter <NUM>, the working catheter <NUM>, and the imaging probe <NUM> are discussed in <CIT>, entitled "Systems and Methods of Integrated Real-Time Visualization,".

As shown in <FIG>, the imaging probe <NUM> is positioned within the passageways <NUM> where the imaging device <NUM> may take intraoperative and real-time images of the target <NUM>. For example, with the imaging probe <NUM> positioned in close proximity to the target <NUM>, an intraoperative external imaging scan may be performed. As discussed above, in some alternative examples, the imaging probe <NUM> may be extended out from the distal end <NUM> of the working catheter <NUM>. For example, the imaging probe <NUM> may replace the tool <NUM> or may be positioned adjacent the tool <NUM> within the working catheter <NUM>. In some examples, while the imaging probe <NUM> is within the sheath <NUM>, the imaging probe <NUM> may replace the tool <NUM> or may be positioned adjacent the tool <NUM> within the working catheter <NUM>.

<FIG> illustrates a method <NUM> for updating a location of a target in an anatomic model according to some examples. For example, updating the location of the target may generally include updating the location based on intraoperative external image data. One or more of the method steps may be performed on the same robotic-assisted medical system used to perform a biopsy or other medical procedure. The method <NUM> is illustrated as a set of operations or processes <NUM> through <NUM> and is described with continuing reference to <FIG> and <FIG>.

At a process <NUM>, preoperative image data is received at a control system (e.g., the control system <NUM>). For example, a CT scan of the patient anatomy may be performed with a CT scanner, and the CT image data may be received by the control system. Alternatively, preoperative image data may be received from other types of imaging systems including magnetic resonance imaging (MRI) systems, fluoroscopy systems, or any other suitable method for obtaining dimensions of anatomic structures. At a process <NUM>, a three-dimensional (3D) model of the anatomic structures (e.g., the anatomic model <NUM> of <FIG>) may be constructed from the preoperative image data by the control system. At a process <NUM>, a target may be identified in the 3D model and/or in the preoperative image data from which it was constructed. For example, the target <NUM> of <FIG> may be identified in the anatomic model <NUM> as a region of interest for investigation and/or treatment. The target may be automatically identified by the control system and confirmed by a user, or the target may be visually identified by the user and manually selected or indicated in the 3D model, for example, via the display system <NUM>. At a process <NUM>, a route through anatomic passageways formed in the anatomic structures is generated. The route may be generated automatically by the control system. Additionally or alternatively, the control system may generate the route based on one or more user inputs. The route may indicate a path along which the medical instrument <NUM>, for example, may be navigated into close proximity with the target. In some examples, the route may be stored in a control system (e.g., in a memory of a control system) and incorporated into the images displayed on the display system <NUM>.

As discussed above, to provide accurate navigation through the anatomic passageways <NUM>, the reference frame <NUM> of the preoperative image data (and subsequently constructed 3D model) may be registered to the reference frame of the outer catheter <NUM> at a process <NUM>. Upon successful registration, a process <NUM> may include generating a virtual navigation view (e.g., the virtual navigation view <NUM> of <FIG>).

At a process <NUM>, navigation guidance is provided as the outer catheter <NUM> is navigated through the passageways <NUM> to a predetermined deployment location in proximity to the target <NUM>. At a process <NUM>, the control system may receive intraoperative image data from the imaging probe <NUM> (e.g., from the imaging device <NUM>). At a process <NUM>, intraoperative external image data may be received at a control system from an intraoperative external imaging system, such as the external imaging device <NUM>. The intraoperative external image data may be displayed (e.g., in a GUI <NUM> of <FIG>) as an intraoperative external image, such as a fluoroscopic image.

The outer catheter <NUM> and the imaging probe <NUM> may be identified in the intraoperative external image. The identification may be made by the control system (e.g., using image processing) and/or by an operator. In order to register the intraoperative external image data to the outer catheter <NUM>, while the intraoperative external imaging is performed, shape data from the outer catheter <NUM> captured during the intraoperative external imaging process <NUM> may be received. The shape data may be captured for only a brief period of time or may be captured during the whole image capture period of the intraoperative external imaging process.

At a process <NUM>, the intraoperative image data captured by the imaging probe <NUM> may be registered to the reference frame of the outer catheter <NUM>. The intraoperative image data may include intraoperative images captured by the imaging probe <NUM>. Each intraoperative image may be registered to the reference frame of the outer catheter <NUM>. Further details regarding the registration between the intraoperative image data captured by the imaging probe <NUM> and the reference frame of the outer catheter <NUM> will be discussed below with respect to <FIG>. For example, systems and techniques will be described that identify a rotation of the intraoperative images relative to the outer catheter <NUM>. Additionally, systems and techniques will be described that measure the insertion distance of the imaging probe <NUM> relative to the distal end <NUM> of the outer catheter <NUM>. In some examples, the control system may determine and/or measure the insertion distance of the imaging probe <NUM> to assist with registering the imaging data captured by the imaging probe <NUM> to the reference frame of the outer catheter <NUM>.

As discussed in more detail below, in some examples, an appearance of one or more identification features may be identified in the imaging data captured by the imaging probe <NUM>. For example, a shape of the identification feature(s), a location of the identification feature(s), and/or any other component regarding how the identification feature(s) looks may be identified in the imaging data captured by the imaging probe <NUM>. The intraoperative image data captured by the imaging probe <NUM> may be registered to the reference frame of the outer catheter <NUM> based on the appearance of the one or more identification features. In some examples, one or more objects captured in the intraoperative image data, e.g., a location of an anatomical target, may be registered to the reference frame of the outer catheter <NUM> based on the appearance of the identification feature(s).

Systems and techniques will also be described that identify the bending (e.g., pitch and/or yaw) of the intraoperative images relative to the longitudinal axis of the outer catheter <NUM>. Additional systems and techniques will be described that determine an orientation of the imaging device <NUM> based on an analysis of the intraoperative external image data captured by the external imaging device <NUM>, for example. In some examples, the control system may determine the orientation of the imaging device <NUM> (and therefore the orientation of a scan plane of the imaging device <NUM>) to assist with registering the imaging data captured by the imaging probe <NUM> to the reference frame of the outer catheter <NUM>.

At a process <NUM>, the location of the anatomic target <NUM> may be adjusted in the virtual navigation image <NUM>. Additional details regarding updating a location of a target in an anatomic model are described in the <CIT>, entitled "Systems and Methods for Updating a Target Location Using Intraoperative Image Data" and the <CIT>, entitled "Systems and Methods for Updating a Target Location Using Intraoperative Image Data,".

The following discussion will be made with reference to illustrative imaging devices. Various examples of imaging devices are provided in <FIG>. Any one or more of the imaging devices discussed below may include a catheter (e.g., the outer catheter <NUM> and/or the working catheter <NUM>), an imaging probe (e.g., the imaging probe <NUM>), and/or an imaging probe sheath (e.g., the imaging probe sheath <NUM>). As discussed above with respect to the process <NUM>, the intraoperative image data captured by the imaging probe <NUM> may be registered to the reference frame of the outer catheter <NUM>. In some examples, the image captured by the imaging probe <NUM> may be registered to the reference frame of the outer catheter <NUM> based on the registration between the intraoperative image data captured by the imaging probe <NUM> and the reference frame of the outer catheter <NUM>, as discussed below. In some examples, based on the registration between the intraoperative image data captured by the imaging probe <NUM> and the reference frame of the outer catheter <NUM>, a location of the imaging probe <NUM> may be registered to the reference frame of the outer catheter <NUM>. For example, the position and orientation of the intraoperative image data captured by the imaging probe <NUM> may be known relative to the position and/or orientation of the imaging probe <NUM> itself. Therefore, because the position and/or orientation of the intraoperative imaging data captured by the imaging probe <NUM> is registered to the reference frame of the outer catheter <NUM>, the position and/or orientation of the imaging probe <NUM> may be registered to the reference frame of the outer catheter <NUM>.

In some examples, a location of the imaging probe sheath <NUM> may be registered to the reference frame of the outer catheter <NUM>. For example, the position and orientation of the imaging probe <NUM> may be known relative to the position and/or orientation of the imaging probe sheath <NUM>. Therefore, because the position and/or orientation of the imaging probe <NUM> is registered to the reference frame of the outer catheter <NUM>, the position and/or orientation of the imaging probe sheath <NUM> may be registered to the reference frame of the outer catheter <NUM>. In some examples, after the location of the imaging probe sheath <NUM> is registered to the reference frame of the outer catheter <NUM>, the imaging probe <NUM> may be removed (e.g., retracted) from the imaging probe sheath <NUM>. One or more additional instruments may then be inserted into the imaging probe sheath <NUM>. The location of the additional instrument(s) may be registered to the imaging probe sheath <NUM> in a similar manner to the registration process between the location of the imaging probe <NUM> and the imaging probe sheath <NUM>. Based on the registration between the additional instrument(s) and the imaging probe sheath <NUM> and/or based on the registration between the location of the imaging probe sheath <NUM> and the reference frame of the outer catheter <NUM>, the location of the additional instrument(s) may be registered to the reference frame of the outer catheter <NUM>.

As discussed above, a rotation of the intraoperative images relative to the outer catheter <NUM> may be identified. <FIG> provides a cross-sectional side view of a portion of an imaging device <NUM>, and <FIG> provides a cross-sectional view of the imaging device <NUM> as viewed in a distal direction. The imaging device <NUM> includes a catheter <NUM>, an imaging probe sheath <NUM>, and an imaging probe <NUM>. In some examples, the catheter <NUM> may be used as the outer catheter <NUM>, and the imaging probe <NUM> may be used as the imaging probe <NUM>. The sheath <NUM> may be movable relative to the catheter <NUM>. In some examples, the imaging probe <NUM> is movable relative to the sheath <NUM> and the catheter <NUM>. Alternatively, the imaging probe <NUM> and the sheath <NUM> may be axially constrained such that there is no axial movement between the imaging probe <NUM> and the sheath <NUM>. In such examples, both the imaging probe <NUM> and the sheath <NUM> are movable together relative to the catheter <NUM>.

In some examples, the catheter <NUM> may include a keyed feature <NUM>, which may include a groove <NUM>. The groove <NUM> may be within a wall <NUM> of the catheter <NUM>. The groove <NUM> may be positioned at any location along the length of the catheter <NUM>, such as at a distal portion, a proximal portion, or any portion between the distal portion and the proximal portion. In some examples, the catheter <NUM> may include more than one keyed feature <NUM>. As shown in <FIG>, the sheath <NUM> may include a corresponding keyed feature <NUM>. In some examples, the keyed feature <NUM> is a protrusion extending from an outer surface of the sheath <NUM>. The keyed feature <NUM> of the sheath <NUM> may be sized to mate with the keyed feature <NUM> of the catheter <NUM>. For example, the keyed feature <NUM> may be sized to fit within the groove <NUM>. In alternative examples, the sheath <NUM> may include one or more grooves, and the catheter <NUM> may include one or more corresponding protrusions.

In some examples, when the keyed feature <NUM> is within the groove <NUM>, the sheath <NUM> may be rotationally constrained relative to the catheter <NUM>. For example, the rotation of the sheath <NUM> may correspond to the rotation of the catheter <NUM> when the sheath <NUM> is positioned within the catheter <NUM>. In such examples, the catheter <NUM> and the sheath <NUM> have the same rotational orientation relative to a longitudinal axis of the catheter <NUM>, for example, when the sheath <NUM> is positioned within the catheter <NUM>. Therefore, the rotational orientation of the sheath <NUM> is fixed to the rotational orientation of the catheter <NUM>. Thus, the rotational orientation of the sheath <NUM> may be known in the reference frame of the catheter <NUM>. In some examples, based on this registration, a location of the sheath <NUM> may be registered to the reference frame of the catheter <NUM>. Therefore, based on the registration between the sheath <NUM> and the catheter <NUM>, the rotational orientation of the imaging probe <NUM> may be known in the reference frame of the catheter <NUM>. In some examples, based on this registration, a location of the imaging probe <NUM> may be registered to the reference frame of the catheter <NUM>. In some examples, the sheath <NUM> may be rotationally constrained relative to the imaging probe <NUM>. When the sheath <NUM> is rotationally constrained relative to both the catheter <NUM> and the imaging probe <NUM>, the catheter <NUM>, the sheath <NUM>, and the imaging probe <NUM> may all have a common rotational orientation. In such examples, the control system may determine the rotational orientation of the imaging probe <NUM>, for example, based on the rotational orientation of the sheath <NUM> and/or the catheter <NUM>. Thus, a tracked rotational orientation of the sheath <NUM> and/or the catheter <NUM> may provide a known orientation for the imaging probe <NUM> that is rotationally fixed with respect to the sheath <NUM> and catheter <NUM>.

In some examples, the catheter <NUM>, the sheath <NUM>, and the imaging probe <NUM> are independently extendable relative to one another. For example, <FIG> illustrates a distal portion (e.g., distal of the portion shown in <FIG>) of the imaging device <NUM> with the sheath <NUM> extended beyond a distal end <NUM> of the catheter <NUM> and illustrates the imaging probe <NUM> extended beyond a distal end <NUM> of the sheath <NUM>. The telescoping extension shown in <FIG> may increase the available insertion distance of the imaging probe <NUM>. Alternatively, the sheath <NUM> may be closed at its distal end <NUM>, which prevents the imaging probe <NUM> from extending beyond the distal end <NUM>. In some examples, such as the example shown in <FIG>, the catheter <NUM> and/or the sheath <NUM> may include the keyed features <NUM>, <NUM> discussed above with respect to <FIG>. The catheter <NUM> and/or the sheath <NUM> may include any other keyed feature(s). Alternatively, the catheter <NUM> and/or the sheath <NUM> might not include keyed features. Any one or more of the catheters and/or sheaths of the imaging devices discussed in the examples below in <FIG> may include keyed features, such as the keyed features <NUM>, <NUM> and/or any other keyed feature(s) or might not include the keyed features.

In some examples, some or all of the sheath <NUM> may be rigid. For example, a distal portion of the sheath <NUM> may be rigid, which may prevent the imaging probe <NUM> from bending when the imaging probe <NUM> is positioned within the distal end <NUM> of the sheath <NUM>. Additionally or alternatively, a rigid distal portion of the sheath <NUM> may limit the amount of bending of the imaging probe <NUM> when the imaging probe <NUM> is extended a small distance beyond the distal end <NUM> of the sheath <NUM>. In some examples, the bending of the imaging probe <NUM> may be so limited that it is negligible. In some examples, the rigidity of the sheath <NUM> may be actively controllable. For example, the control system may send signals to the sheath <NUM> to control whether the sheath <NUM> is rigid or flexible. In some examples, the signals from the control system may cause one or more control cables within the sheath <NUM> to be pulled in a proximal direction, which may cause the sheath <NUM> to become rigid. Additionally or alternatively, the signals from the control system may cause a rigidizable feature (e.g., a balloon, a rigidizable wire, or any other rigidizable feature) to rigidize, which may cause the sheath <NUM> to become rigid. The control system may also control which portion(s) of the sheath <NUM> is rigid and which portion(s) of the sheath <NUM> is flexible. For example, the control system may cause the distal portion of the sheath <NUM> to be rigid while maintaining the remainder of the sheath <NUM> in a flexible state. In some examples, one or more of the rigidizable features discussed above may be positioned at the distal portion of the sheath <NUM>. In such examples, when the rigidizable feature is rigidized, the distal portion of the sheath <NUM> may become rigid, and the proximal portion of the sheath <NUM> may remain flexible.

The imaging probe <NUM> may include an imaging device <NUM>, which may be positioned near a distal end section <NUM> of the imaging probe <NUM>. The imaging device <NUM> may be similar to the imaging device <NUM> discussed above. For example, the imaging device <NUM> may be an ultrasound transducer. While the imaging device <NUM> is shown as positioned near the distal end section <NUM>, such as at a distal portion of the imaging probe <NUM>, the imaging device <NUM> may be positioned at any other position of the imaging probe <NUM>.

<FIG> provides a cross-sectional side view of an imaging device <NUM>. The imaging device <NUM> includes a catheter <NUM>, an imaging probe sheath <NUM>, and an imaging probe <NUM>. The sheath <NUM> may be movable in an axial direction relative to the catheter <NUM>, and the imaging probe <NUM> may be movable in an axial direction relative to the sheath <NUM>. The imaging probe <NUM> may include an imaging device <NUM>. In some examples, the sheath <NUM> may include one or more identification features <NUM>. An appearance of the identification feature(s) <NUM> may be detected by the imaging device <NUM>. For example, a shape of the identification feature(s) <NUM>, a location of the identification feature(s) <NUM>, and/or any other component regarding how the identification feature(s) looks may be identified in the imaging data captured by the imaging device <NUM>. In some examples, the identification feature <NUM> may be positioned so that at least a portion of the identification feature overlaps a scan plane <NUM> of the imaging device <NUM> and thus is visible in the images generated by the imaging device <NUM>. The scan plane (or imaging plane) <NUM> of the imaging device <NUM> may extend radially outward from the imaging device <NUM>. In some examples, the scan plane <NUM> may have a <NUM>° field of view perpendicular to a longitudinal axis L of the imaging probe <NUM>. Further details regarding the identification feature(s) will be discussed below.

The identification feature(s) may be more easily detected by the imaging device <NUM> when there is good acoustical coupling between the imaging probe <NUM> and the sheath <NUM>. When the quality of the acoustical coupling increases, the clarity of the image captured by the imaging probe <NUM> (e.g., captured by the imaging device <NUM>) may increase. In some examples, a cavity <NUM> may be present between an outer surface of the imaging probe <NUM> and an inner surface of the sheath <NUM>. The quality of the acoustical coupling between the imaging probe <NUM> and the sheath <NUM> may be high when an acoustic impedance of a substance present within the cavity <NUM> is similar to an acoustic impedance of the patient anatomy within which the imaging probe <NUM> is located (e.g., the tissue <NUM>). For example, the cavity <NUM> may be filled with saline. Saline may have an acoustic impedance similar to an acoustic impedance of the patient anatomy within which the imaging probe <NUM> is located. Therefore, when saline is introduced into the cavity <NUM>, there may be good acoustical coupling between the imaging probe <NUM> and the sheath <NUM>. While the above discussion is made with respect to saline being introduced into the cavity <NUM>, any other suitable fluid, such as air, may be introduced into the cavity <NUM>. In some examples, air may have an acoustic impedance that is different from the acoustic impedance of the patient anatomy within which the imaging probe <NUM> is located. In such examples, when air is introduced into the cavity <NUM>, the acoustical coupling between the imaging probe <NUM> and the sheath <NUM> may be of a lesser quality than when saline is introduced into the cavity <NUM>.

In some examples, the sheath <NUM> itself may be made of a material (e.g., one or more PEBA polymers or one or more polyurethane polymers, such as Tecoflex 80A) that has an acoustic impedance that is similar to the acoustic impedance of the patient anatomy within which the imaging probe <NUM> is located. This may help the identification feature be more visible in the image captured by the imaging probe <NUM>. For example, a greater contrast may be shown between the identification feature and the sheath <NUM> and/or a difference in color between the identification feature and the sheath <NUM> may be more defined.

As shown in <FIG> and <FIG>, the identification feature may be an elongate member <NUM>, which may be an elongate wire. The elongate wire <NUM> may be positioned outside of the sheath <NUM> (<FIG>) or within a wall <NUM> of the sheath <NUM> (<FIG>). In some examples, the sheath <NUM> may include more than one wire <NUM>. The elongate wire <NUM> may be metal (e.g., tungsten, stainless steel, or any other metallic substance). In some examples, the elongate wire <NUM> is flat, but may also be cylindrical or any other suitable shape. <FIG> and <FIG> show the elongate wire <NUM> extending along a portion of the sheath <NUM>, which may be the distal portion of the sheath <NUM>. Alternatively, the elongate wire <NUM> may extend along an entire length of the sheath <NUM>. In some examples, the sheath <NUM> may include multiple elongate wires, and the wires may extend along separate portions of the sheath <NUM>.

In examples when the elongate wire <NUM> is positioned outside of the sheath <NUM>, as shown in <FIG>, the elongate wire <NUM> may be coupled to an outer surface <NUM> of the sheath <NUM>. Alternatively, the elongate wire <NUM> may be coupled to the sheath <NUM> via one or more connection members (e.g., connection wires, scaffolding, and/or the like) such that the elongate wire <NUM> is spaced from the outer surface <NUM> of the sheath <NUM>. In some examples, a portion of the elongate wire <NUM> may be spaced from the outer surface <NUM> of the sheath <NUM>, and wherein another portion of the elongate wire <NUM> may be in contact with the outer surface <NUM> of the sheath <NUM>. In some examples, the appearance of the elongate wire <NUM> may be more visible in the image captured by the imaging probe <NUM> when the elongate wire <NUM> is positioned outside of the sheath <NUM> than when the elongate wire <NUM> is positioned within the wall <NUM> of the sheath <NUM>. Additionally, a thicker elongate wire <NUM> may be more visible in the image captured by the imaging probe <NUM> than a thinner elongate wire <NUM>. In some examples, the elongate wire <NUM> may have a varying thickness along a length of the elongate wire <NUM>.

As discussed above, the insertion distance of the imaging probe <NUM> relative to the distal end of the catheter <NUM> may be measured. For example, the control system may determine the insertion distance of the sheath <NUM> based on the thickness of the elongate wire <NUM> that is visible in the image captured by the imaging probe <NUM>. In examples when the sheath <NUM> and the imaging probe <NUM> are axially constrained (e.g., the insertion distance of the sheath <NUM> corresponds to the insertion distance of the imaging probe <NUM>), the control system may determine the insertion distance of the imaging probe <NUM> based on the insertion distance of the sheath <NUM>.

In some examples, control system may register the imaging data captured by the imaging probe <NUM> to the reference frame of the catheter <NUM> based on the insertion distance of the imaging probe <NUM> relative to the catheter <NUM>. For example, the control system may determine the insertion distance of the imaging probe <NUM> relative to the sheath <NUM> based on the appearance of the identification feature (e.g., the elongate wire <NUM>) that is visible in the image captured by the imaging probe <NUM>. The control system may determine the insertion distance of the sheath <NUM> relative to the catheter <NUM> as discussed in greater detail below. Based on these relative insertion distance determinations, the control system may determine the insertion distance of the imaging probe <NUM> relative to the catheter <NUM>. The control system may register the imaging data captured by the imaging probe <NUM> to the reference frame of the catheter <NUM> based on the insertion distance of the imaging probe <NUM> relative to the catheter <NUM>.

In some examples, the appearance of the elongate wire <NUM> may be identifiable in the intraoperative external image data at different angles around the circumference of the sheath <NUM>. The control system may determine the rotational orientation of the sheath <NUM> based on the angle at which the appearance of the elongate wire <NUM> is oriented around the circumference of the sheath <NUM> in the image captured by the imaging probe <NUM>. In examples when the sheath <NUM> and the imaging probe <NUM> are rotationally constrained (e.g., rotationally fixed), the control system may determine the rotational orientation of the imaging probe <NUM> based on the rotational orientation of the sheath <NUM>. Additionally or alternatively, the control system may determine the rotational orientation of the imaging data captured by the imaging probe <NUM> relative to the rotational orientation of the sheath <NUM> based on the appearance of the elongate wire <NUM> in the imaging data captured by the imaging probe <NUM>.

As discussed above with respect to <FIG>, in some examples, the rotational orientation of the sheath <NUM> may be fixed with respect to the rotational orientation of the catheter <NUM>. In such examples, the control system may determine the rotational orientation of the imaging data captured by the imaging probe <NUM> relative to the rotational orientation of the catheter <NUM> based on the fixed rotational orientation of the sheath <NUM> to the rotational orientation of the catheter <NUM>.

In examples when the elongate wire <NUM> is positioned within the wall <NUM> of the sheath <NUM>, as shown in <FIG>, the elongate wire <NUM> may be embedded within the wall <NUM>. Alternatively, the elongate wire <NUM> may be inserted through a lumen <NUM> in the wall <NUM>. In some examples, the lumen in the wall <NUM> may be filled with air. Because air has an acoustic impedance that is different from the patient anatomy within which the imaging probe <NUM> is located, the air-filled lumen (with or without the elongate wire <NUM> positioned within the lumen) may be identified in the image captured by the imaging device <NUM> of the imaging probe <NUM>. In some examples, the elongate wire <NUM> may be inserted into the lumen when the lumen is filled with air. In other examples, the elongate wire <NUM> may be inserted into the lumen when the lumen is filled with saline or any other fluid.

With reference now to <FIG>, in some examples, the wall <NUM> of the sheath <NUM> may be non-concentric along at least a portion of a length of the sheath <NUM>. For example, a portion <NUM> of the wall <NUM> may protrude out from the sheath <NUM> in a radial direction. As shown in <FIG>, the portion <NUM> may be a non-concentric portion of the wall <NUM>. The identification feature may be positioned within the non-concentric portion <NUM>. In some examples, the identification feature may be a marker <NUM> positioned within the non-concentric portion <NUM>. In some examples, the marker <NUM> may be a sphere or other toroidal object. Having a non-concentric portion in the sheath wall may allow for larger identification features to be placed in/on the sheath <NUM>. For example, the marker <NUM> may be larger (e.g., thicker) than the elongate wire <NUM> discussed above. Larger identification features may be more visible in the image captured by the imaging probe <NUM> than smaller identification features.

In some examples, the elongate wire <NUM> may extend through the non-concentric portion <NUM>. As discussed above, the elongate wire <NUM> may have a varying thickness along a length of the elongate wire <NUM>. In some examples, a first portion of the elongate wire <NUM> extends through a concentric portion of the wall <NUM>, and a second portion of the elongate wire <NUM> extends through the non-concentric portion <NUM> of the wall <NUM>. The second portion of the elongate wire <NUM> within the non-concentric portion <NUM> of the wall <NUM> may be thicker than the first portion of the elongate wire <NUM> within the concentric portion of the wall <NUM>. The thicker portion of the elongate wire <NUM> may be more visible in the image captured by the imaging probe <NUM> than the thinner portion of the elongate wire <NUM>. In some examples, the second portion of the elongate wire <NUM> is thinner than the first portion of the elongate wire <NUM>.

<FIG> illustrates a cross-section view of an alternative example of the sheath <NUM> when viewing the sheath <NUM> from a distal-looking perspective. As discussed above, the wall <NUM> of the sheath <NUM> may include a non-concentric portion <NUM> and a concentric portion <NUM>. The non-concentric portion <NUM> may extend along at least a portion of a length of the sheath <NUM>. In some examples, the non-concentric portion <NUM> may extend along the entire length of the sheath <NUM>. The non-concentric portion <NUM> may have a thickness t1, and the concentric portion <NUM> may have a thickness t2. In some examples, the thickness t1 is greater than the thickness t2. The identification feature may be positioned within the non-concentric portion <NUM>. In some examples, the identification feature may be one or more lumens <NUM> positioned within the non-concentric portion <NUM>. While <FIG> shows three lumens <NUM> within the non-concentric portion <NUM>, any number of lumens <NUM> may be included, such as one lumen, two lumens, four lumens, or any other number of lumens. In some examples, the lumens <NUM> may be filled with air or any other substance that may be visible in the image captured by the imaging probe <NUM>.

With reference now to <FIG>, the identification feature may be one or more markers <NUM>. The markers <NUM> may be spherical, triangular, rectangular, star-shaped, and/or any other shape. In some examples, each of the markers <NUM> is the same shape (e.g., each marker is a sphere). Alternatively, one or more markers may be shaped differently than the other markers (e.g., some markers may be spheres, and some markers may be stars). The markers <NUM> may be aligned in a pattern that may be identified in the image captured by the imaging probe <NUM>. In some examples, the markers <NUM> may be a first shape at a first insertion distance along the sheath <NUM> and may be a second shape at a second insertion distance along the sheath <NUM>. For example, a portion of the markers <NUM> may be spheres, and a portion of the markers <NUM> may be stars. The spheres may be positioned distally of the stars in some examples. In other examples, the stars may be positioned distally of the spheres. As shown in <FIG>, the markers <NUM> may be positioned within the wall <NUM> of the sheath <NUM>. Additionally or alternatively, the markers <NUM> may be positioned outside of the sheath <NUM>, as discussed above with respect to <FIG>. The markers <NUM> may be aligned linearly or in any other manner, such as in a curve, in a circle, in one or more layers, and/or the like. In some examples, the markers <NUM> may be aligned parallel to a longitudinal axis of the sheath <NUM>. In some alternative examples, the markers <NUM> may be aligned perpendicular to the longitudinal axis of the sheath <NUM>.

In some examples, the markers <NUM> may be visible in an intraoperative external image (e.g., the intraoperative external image <NUM> in <FIG>) captured by an intraoperative external imaging device, such as a fluoroscopic imaging device, a CT imaging device, and/or the like. A processing system, such as an image processing system, may analyze the intraoperative external image to determine the insertion distance of the sheath <NUM> based on the markers <NUM>. For example, the control system may determine how many markers <NUM> are extended beyond the distal end <NUM> of the catheter <NUM>, which may indicate the insertion distance of the sheath <NUM>. Additionally or alternatively, the markers <NUM> may be visible in the image captured by the imaging probe <NUM>. A processing system, such as an image processing system, may analyze the captured image to determine the insertion distance of the sheath <NUM> based on the markers <NUM>. For example, the control system may determine how many markers <NUM> are visible in the captured image, which may indicate the insertion distance of the sheath <NUM>. In examples when the sheath <NUM> and the imaging probe <NUM> are axially constrained, the insertion distance of the sheath <NUM> may correspond to the insertion distance of the imaging probe <NUM>.

In some examples, a proximal end of the imaging probe <NUM> may include one or more markers, which may be similar to the markers <NUM>. As the imaging probe <NUM> is extended from the catheter <NUM> and/or from the sheath <NUM>, the user and/or the control system may analyze the markers at the proximal end of the imaging probe <NUM> to determine the insertion distance of the imaging probe <NUM>.

In some examples, as shown in <FIG>, the identification feature may be an active component <NUM>, such as a transducer, an electromagnetic emitter, or any other active component. The active component <NUM> may emit a signal that is detectable by the control system. Based on the signal, the control system may determine the position and/or the rotational orientation of the sheath <NUM>. In examples when the sheath <NUM> and the imaging probe <NUM> are rotationally constrained, the control system may determine the rotational orientation of the imaging probe <NUM> based on the signal received from the active component <NUM>. In some examples, more than one active component <NUM> may be included at different axial positions along the length of the sheath <NUM> and/or at different radial positions around the circumference of the sheath <NUM>. One or more of the active components may emit different signals, such as signals with different strengths and/or different frequencies. Based on the different signals received from the different active components <NUM>, the control system may determine the rotational orientation and/or the insertion distance of the sheath <NUM>. As discussed above, the active component(s) <NUM> may be positioned within the wall <NUM> of the sheath <NUM> or outside of the sheath <NUM>.

With reference to <FIG>, the identification feature may include a plurality of wires <NUM>. The wires <NUM> may include one or more of an elongate wire <NUM>, a helical wire <NUM>, and/or a helical wire <NUM>. The wires <NUM> may include any additional number of wires. In some examples, the wires <NUM> may include the elongate wire <NUM> and only one of the helical wire <NUM> or the helical wire <NUM>. In some examples, the elongate wire <NUM> may be straight such that it is parallel with a longitudinal axis L of the imaging probe <NUM>. While <FIG> shows the wire <NUM> within the wall <NUM> of the sheath <NUM> and the wires <NUM>, <NUM> outside of the sheath <NUM>, one, some, or all of the wires <NUM> may be positioned within the wall <NUM>, outside of the sheath <NUM>, or in any combination, as discussed above. Each of the wires <NUM> may be similar to the elongate wire <NUM> discussed above with respect to <FIG> and <FIG>. The helical wires <NUM> and <NUM> may be coiled around the sheath <NUM>, such as around the outer surface of the sheath <NUM> or within the wall of the sheath <NUM>.

In some examples, one, some, or all of the wires <NUM>-<NUM> may be identified (by the control system and/or by the user) in the image captured by the imaging probe <NUM>. As discussed above with respect to the elongate wire <NUM>, the control system may determine the insertion distance of the imaging probe <NUM> based on the captured image of the wire <NUM>. Additionally or alternatively, the control system may determine the rotational orientation of the sheath <NUM> based on the captured images of the wires <NUM>, <NUM>. For example, as the sheath <NUM> is inserted through the catheter <NUM>, the imaging probe <NUM> (e.g., via the imaging device <NUM>) may capture images of one or more of the wires <NUM>, <NUM> at different rotational orientations. The different rotational orientations may indicate the insertion distance of the sheath <NUM>. Additionally or alternatively, the images of the wires <NUM>, <NUM> may indicate the bending of the sheath <NUM>. For example, when the sheath <NUM> is bent, one side of the sheath <NUM> is compressed and the opposing side of the sheath <NUM> is stretched. The wires <NUM>, <NUM> will similarly be compressed on one side and stretched on an opposing side. The spacing between the wires <NUM>, <NUM> is greater on the side of the wire <NUM>, <NUM> that is stretched than on the side of the wire <NUM>, <NUM> that is compressed. Based on the spacing of the wires <NUM>, <NUM> shown in the images of the wires <NUM>, <NUM>, the bending of the wires <NUM>, <NUM> may be identified. The bending of the wires <NUM>, <NUM> corresponds to the bending of the sheath <NUM>. Therefore, the bending of the sheath <NUM> may be determined based on the bending of the wires <NUM>, <NUM>. In examples when the sheath <NUM> and the imaging probe <NUM> are rotationally constrained, the rotational orientation of the imaging probe <NUM> corresponds to the rotational orientation of the sheath <NUM>.

With reference now to <FIG>, the identification feature may be a portion of the sheath <NUM> itself. For example, a portion <NUM> of the sheath <NUM> may be an identification feature and may be formed of a composite material. In some examples, the portion <NUM> may be formed as part of the wall <NUM> of the sheath <NUM>. Alternatively, the portion <NUM> may be coupled to the outer surface <NUM> of the sheath <NUM>. The composite material may be, for example, a combination of a non-attenuating polymer (e.g., one or more PEBA polymers or one or more polyurethane polymers, such as Tecoflex 80A) and an attenuating material (e.g., tungsten particles, gas bubbles, hollow glass microspheres, and/or the like). The portion <NUM> may extend along an entire length of the sheath <NUM>, along separate portions of the length of the sheath <NUM>, or along a portion of the sheath <NUM>, such as the distal portion. The portion <NUM> may be visible in the image captured by the imaging probe <NUM>. In some examples, the control system may identify the portion <NUM> in the image and determine a rotational orientation of the sheath <NUM> based on the identified portion <NUM>.

In some examples, an elongate member, such as a hypo tube, may be positioned within or around the sheath <NUM>. The hypo tube may act as the identification feature. Alternatively, the hypo tube may house the identification feature. In some examples, the hypo tube may act as one identification feature and may house one or more additional identification features. <FIG> illustrates an elongate member <NUM>, which may be a hypo tube. The hypo tube <NUM> may be positioned within or around the sheath <NUM>. When the imaging probe <NUM> is received by the sheath <NUM>, the imaging probe <NUM> may be inserted through the hypo tube <NUM>. The hypo tube <NUM> may include a slot <NUM>, which may house any one or more of the identification features discussed above. The slot <NUM> may extend around any portion of the circumference of the hypo tube <NUM>, such as one quarter of the circumference, one half of the circumference, three quarters of the circumference, or any other amount. In some examples, the hypo tube <NUM> may include slits in the wall of the hypo tube <NUM> to help increase the flexibility of the hypo tube <NUM> as the hypo tube <NUM> bends with the sheath <NUM>. In some examples, the hypo tube <NUM> may be positioned at a distal portion of the sheath <NUM>. The hypo tube <NUM> may be positioned such that the identification feature in the slot <NUM> is visible in the image captured by the imaging probe <NUM>. In some examples, the hypo tube <NUM> itself may be the identification feature and may be visible in the image captured by the imaging probe <NUM>.

<FIG> illustrates an elongate member <NUM>, which may be a hypo tube. In some examples, the hypo tube <NUM> may be positioned within or around the sheath <NUM> and may replace the hypo tube <NUM>. In some alternative examples, both hypo tubes <NUM>, <NUM> may be positioned within or around the sheath <NUM>. As discussed above with respect to the hypo tube <NUM>, when the imaging probe <NUM> is received by the sheath <NUM>, the imaging probe <NUM> may be inserted through the hypo tube <NUM>. The hypo tube <NUM> may include a ribbon marker <NUM>, which may be the identification feature. The ribbon marker <NUM> may extend around any portion of the circumference of the hypo tube <NUM>, such as one tenth of the circumference, one quarter of the circumference, or any other amount. In some examples, the ribbon marker <NUM> may include slits to help increase the flexibility of the ribbon marker <NUM> as the ribbon marker <NUM> bends with the sheath <NUM>. In some examples, the hypo tube <NUM> may be positioned at a distal portion of the sheath <NUM>. The hypo tube <NUM> may be positioned such that the ribbon marker <NUM> is visible in the image captured by the imaging probe <NUM>.

Turning to <FIG>, in some examples, the identification feature may be an expandable member. For example, when the sheath <NUM> is extended beyond the distal end <NUM> of the catheter <NUM>, an identification feature <NUM> may radially expand from a collapsed position to an expanded position. The identification feature <NUM> may be in the collapsed position when the sheath is within the catheter <NUM>. In some examples, the identification feature <NUM> is a balloon but may also be scaffolding, a spring-loaded feature, or any other expandable member. The balloon <NUM> itself may be detectable in the image captured by the imaging probe <NUM>. Additionally or alternatively, a marker <NUM> may be coupled to the balloon <NUM>. The marker <NUM> may be detectable in the image captured by the imaging probe <NUM>. In some examples, the marker <NUM> may be a wire (similar to the elongate wire <NUM> discussed above with respect to <FIG>) or may be any of the other identification features discussed above. In some examples, the marker <NUM> may be the identification feature.

As shown in <FIG>, the marker <NUM> may be coupled to an outside surface of the balloon <NUM>. Additionally or alternatively, the marker <NUM> may be positioned within the balloon <NUM> (e.g., embedded within the balloon <NUM>) as shown in <FIG>. In some examples, the marker <NUM> may surround the balloon <NUM> such that the marker <NUM> is concentric with the balloon <NUM>. Alternatively, the marker <NUM> may surround a portion of the balloon <NUM> (e.g., a portion of the circumference of the balloon).

In some examples, the balloon <NUM> may surround a portion of the sheath <NUM> (e.g., a portion of a circumference of the sheath <NUM>), as shown in <FIG>. For example, the balloon <NUM> may surround half of the sheath <NUM>, three-quarters of the sheath <NUM>, one-quarter of the sheath <NUM>, or any other amount of the sheath <NUM>. In such examples, when the sheath <NUM> is extended out of the catheter <NUM> and the balloon <NUM> expands, the balloon <NUM> expands around the portion of the sheath <NUM> to which the balloon <NUM> is coupled. The expanded portion of the balloon <NUM> and/or the marker <NUM>, which may be coupled to the balloon <NUM> as discussed above, may be identifiable in the image captured by the imaging probe <NUM>.

In some examples, the balloon <NUM> may be pressurized based on the bending of the sheath <NUM>. For example, one or more sensors, such as pressure sensors, shape sensors, or any other suitable sensor, may be positioned along the length of the sheath <NUM>. When the sheath <NUM> bends, the control system may receive a signal from one or more of the sensors indicating which portion of the sheath <NUM> is bent. Based on this received sensor data, the control system may determine how the sheath <NUM> (and the imaging probe <NUM>) is bent.

While the above discussion is made with respect to one balloon <NUM>, multiple balloons (or other expandable features) may be coupled to the sheath <NUM> in some examples. In such examples, the balloons may be aligned parallel with a longitudinal axis of the sheath <NUM>. In other examples, the balloons may form a spiral or other curved pattern around the sheath <NUM>. As the sheath <NUM> is extended from the catheter <NUM>, each balloon may expand as each balloon is extended beyond the distal end <NUM> of the catheter <NUM>. The balloons may be identifiable in intraoperative external image data, such as fluoroscopic image data, that may be captured as the sheath <NUM> is extended from the catheter <NUM>. In some examples, the control system and/or a user may analyze the intraoperative external image data to determine how many balloons have expanded. Based on the number of expanded balloons (and any partially expanded balloons), the control system and/or the user may determine the insertion distance of the sheath <NUM>. In examples when the sheath <NUM> and the imaging probe <NUM> are axially constrained, the insertion distance of the sheath <NUM> may also correspond to the insertion distance of the imaging probe <NUM>. In examples when the balloons form a spiral or other curved pattern around the sheath <NUM>, the balloons may be identifiable in the intraoperative external image data at different angles around the circumference of the sheath <NUM>.

Additionally or alternatively, the balloons may be identifiable in the intraoperative image captured by the imaging probe <NUM>. For example, as the sheath <NUM> is extended from the catheter <NUM> and each balloon expands as it is extended beyond the distal end <NUM> of the catheter <NUM>, each expanded balloon may be visible in the image captured by the imaging probe <NUM>. In some examples, the control system and/or a user may analyze the intraoperative image to determine how many balloons have expanded. Based on the number of expanded balloons (and any partially expanded balloons), the control system and/or the user may determine how far the sheath <NUM> is extended from the catheter <NUM>. In examples when the sheath <NUM> and the imaging probe <NUM> are axially constrained, the extension distance of the sheath <NUM> from the catheter <NUM> may also correspond to the extension distance of the imaging probe <NUM> from the catheter <NUM>. In examples when the balloons form a spiral or other curved pattern around the sheath <NUM>, the balloons may be identifiable in the intraoperative image at different angles around the circumference of the sheath <NUM>.

As discussed above, the bending (e.g., pitch and/or yaw) of the imaging probe <NUM> relative to the longitudinal axis of the catheter <NUM> may be identified. In some examples, the balloons may be identifiable in the image captured by the imaging probe <NUM>. In some examples, the control system and/or a user may analyze this image to determine how many balloons have expanded as the sheath <NUM> is extended from the catheter <NUM>. Based on the number of expanded balloons (and any partially expanded balloons), the control system and/or the user may determine the bend angle (e.g., pitch and/or yaw) of the sheath <NUM>. In some examples, the balloons may be actively controllable. For example, the control system may send signals to one or more of the balloons to control which balloons are expanded and/or the amount of expansion, such as any partial expansion, of the balloons. In some examples, the control system may control the expansion of one or more balloons over time such that the balloons are open and closed in a temporal pattern. For example, a distalmost balloon may be expanded and when it reaches full expansion, the adjacent balloon may be expanded. In some examples, when the adjacent balloon reaches full expansion, the distalmost balloon may be deflated. The control system may control the expansion of the balloons according to any other temporal pattern.

In some examples, as the sheath <NUM> bends, the amount of expansion of one or more of the balloons may change. The control system may detect these changes in expansion and may determine the bent orientation of the sheath <NUM> based on the received signals indicating the changes in expansion of the balloons. For example, the control system may receive one or more signals indicating that one or more balloons on one side of the sheath <NUM> are partially deflated and/or fully deflated. Based on these signals, the control system may determine that the side of the sheath <NUM> with the deflated balloons is bent. The control system may also determine the amount of bending based on the received signals.

While several examples of identification features are discussed above, any one or more similar identification features may be included in the imaging device <NUM>. Additionally, any one or more of the identification features discussed above may be included, in any combination, in the imaging device <NUM>. For example, the imaging device <NUM> may include an elongate wire (e.g., the elongate wire <NUM>) and an expandable feature (e.g., the balloon <NUM>).

In some examples, the identification feature may be visible in the raw imaging data (e.g., ultrasound data) received from the imaging probe <NUM>, which may be an ultrasound imaging probe. A processing system, such as an image processor, and/or the control system may detect the identification feature in the raw imaging data to determine the rotational orientation of the image captured by the imaging probe <NUM> relative to the catheter <NUM>, for example, using any one or more of the methods discussed above. The processing system may optionally "remove" the identification feature from the image that is displayed to the user such that the identification feature is not present in the image displayed to the user. In such examples, the processing system may detect the rotational orientation of the captured image, but the image displayed to the user is kept "clean. " This may help declutter the displayed image and may allow the user to perform the medical procedure (or other procedure) more efficiently.

In some examples, the user may test the articulation of the catheter <NUM> and may observe how the image captured by the imaging probe <NUM> changes during the articulation. Based on the observed changes in the captured image, the user may determine the registration between the captured image and the catheter <NUM>. For example, if the user articulates the catheter <NUM> to a "<NUM>:<NUM>" (i.e., <NUM> o'clock) orientation and the captured image indicates that the catheter <NUM> is oriented in a "<NUM>:<NUM>" orientation, then the user may determine that the articulation of the catheter <NUM> and the captured image are inversely related. In some examples, the control system may provide instructions to the user to perform this articulation after the control system and/or the user has identified the anatomical target (e.g., the target <NUM>) in the image captured by the imaging probe <NUM>. Additionally or alternatively, the control system may articulate the catheter <NUM> to determine the registration between the catheter <NUM> and the captured image. Additionally or alternatively, the control system may analyze the image captured by the imaging probe <NUM> to determine how the image captured by the imaging probe <NUM> changes during articulation of the catheter <NUM>.

In some examples, a graphical user interface (GUI) may be used to assist with one or more aspects of the medical procedure. For example, an image of a medical instrument may be displayed on the GUI, and the position of the image of the medical instrument may be updated as the medical instrument is navigated through the patient anatomy. Additionally or alternatively, one or more images of an imaging device may be displayed on the GUI.

As shown in <FIG>, a graphical user interface (GUI) <NUM> includes a virtual navigation view <NUM>. The virtual navigation view <NUM> may illustrate a medical instrument <NUM> (e.g., the medical instrument <NUM> of <FIG>), one or more anatomical passageways <NUM>, and an anatomical target <NUM> (e.g., the target <NUM> of <FIG>). The virtual navigation view <NUM> may be generated by registering preoperative image data (and a subsequently constructed 3D model) to a current location of the medical instrument <NUM>. The GUI <NUM> may also include a reduced anatomical model <NUM>, an intraoperative external image <NUM> (e.g., a fluoroscopic image), a virtual path view <NUM>, an intraoperative image <NUM>, and an icon menu <NUM>. The path view <NUM> may illustrate the view along a preoperatively planned traversal path <NUM> for the medical instrument <NUM> to follow through the anatomic passageways <NUM> identified in an anatomic model generated from preoperative image data (e.g., CT image data). The path view <NUM> may provide an interior view (e.g., a pseudo-endoscopic view) of one or more of the anatomic passageways <NUM> as the medical instrument <NUM> navigates the anatomic passageways <NUM> and may also selectively depict structures outside of the passageway walls, such as the target location, vasculature, pleura, or other anatomical structures. Further details of the GUI <NUM> may be found in the <CIT>, entitled "Systems and Methods for Updating a Target Location Using Intraoperative Image Data,".

As shown in <FIG>, a distal end <NUM> of the medical instrument <NUM> may be navigated to an initial deployment location <NUM> near the anatomical target <NUM>. The current shape of the medical instrument <NUM> and the location of the distal end <NUM> may be displayed in the virtual navigation view <NUM>. Although illustrative arrangements of views are depicted in <FIG>, it is to be understood that the GUI <NUM> may display any number of views, in any arrangement, and/or on any number of screens. In some examples, the number of concurrently displayed views may be varied by opening and closing views, minimizing and maximizing views, moving views between a foreground and a background of the GUI <NUM>, switching between screens, and/or otherwise fully or partially obscuring views. Similarly, the arrangement of the views-including their size, shape, orientation, ordering (in a case of overlapping views), and/or the like-may vary and/or may be user-configurable.

With reference to <FIG>, an imaging probe <NUM> (e.g., the imaging probe <NUM>) and a sheath <NUM> (e.g., the sheath <NUM>) may be deployed through a lumen of the medical instrument <NUM>. A field of view of the imaging probe <NUM>, which may be a field of view of an imaging device <NUM> (e.g., the imaging device <NUM>), is illustrated as an imaging plane <NUM>. As shown in <FIG>, the imaging plane <NUM> may be located at or near the distal end of the imaging probe <NUM>.

In some examples, an insertion distance D of the imaging probe <NUM> may be measured by the control system. For example, the control system and/or an image processing system may analyze the intraoperative external image <NUM> to measure the insertion distance D. In some examples, the appearance of the identification feature <NUM> in the intraoperative external image <NUM> is different for different insertion distances of the imaging probe <NUM> relative to the sheath <NUM>. The control system may determine the insertion distance of the imaging probe <NUM> relative to the sheath <NUM> based on the appearance of the identification feature <NUM> in the intraoperative external image <NUM>.

Additionally or alternatively, the insertion distance D may be measured by a user and then input into the control system (e.g., via the GUI <NUM>). For example, a sensor at a proximal portion of the imaging probe <NUM> may measure how far the distal end of the imaging probe <NUM> is extended from the distal end <NUM> of the medical instrument <NUM>. Additionally or alternatively, a sensor at a proximal portion of the sheath <NUM> may measure how far the distal end of the imaging probe <NUM> is extended from the distal end <NUM> of the medical instrument <NUM>. Additionally or alternatively, a sensor at a proximal portion of the sheath <NUM> may measure how far the distal end of the sheath <NUM> is extended from the distal end <NUM> of the medical instrument <NUM>. Then, the control system and/or an image processing system may analyze the intraoperative external image <NUM> to determine how far into the sheath the imaging probe <NUM> is inserted to determine how far the distal end of the imaging probe <NUM> is extended from the distal end <NUM> of the medical instrument <NUM>. Additionally or alternatively, a sensor at a proximal portion of the medical instrument <NUM> may measure how far the distal end of the imaging probe <NUM> is extended from the distal end <NUM> of the medical instrument <NUM>. Other measurement techniques may be used without departing from the examples discussed herein.

Additionally or alternatively, the control system and/or the image processing system may analyze the intraoperative external image <NUM> to determine the off-axis bending (e.g., the pitch and/or the yaw) of the imaging probe <NUM>. In some examples, the control system and/or the image processing system may analyze the intraoperative external image <NUM> to determine the orientation of the imaging device <NUM> at the distal end of the imaging probe <NUM>. As discussed above, the imaging device <NUM> may be a radial EBUS transducer that rotates to obtain one or more ultrasound images. In some examples, the orientation of the imaging device <NUM> may be seen in the intraoperative external image <NUM> when the imaging device <NUM> is not rotating. As further discussed above, the image captured by the imaging probe <NUM> may include an image of an identification feature, which may be present on an imaging probe sheath (e.g., the sheath <NUM> of <FIG>). In some examples, the identification feature, such as an identification feature <NUM>, may be visible in the intraoperative external image <NUM> (e.g., when the identification feature is a radiopaque marker). The control system may analyze the intraoperative external image <NUM> to compare the orientation of the identification feature with the orientation of the imaging device <NUM>. Based on this comparison, the control system may determine the orientation of the imaging probe <NUM> relative to the medical instrument <NUM>. In some examples, the appearance of the identification feature <NUM> in the intraoperative external image <NUM> is different for different off-axis bending orientations of the sheath <NUM>. The control system may determine the off-axis bending of the imaging probe <NUM> based on the appearance of the identification feature <NUM> in the intraoperative external image <NUM>.

The imaging probe <NUM> may include a shape sensor, which may extend along a length of the imaging probe <NUM>. In some additional examples, the medical instrument <NUM> may include a shape sensor. Based on shape data received from the shape sensor of the imaging probe <NUM>, the control system may determine the shape of the imaging probe <NUM>. Based on shape data received from the shape sensor of the medical instrument <NUM>, the control system may determine the shape of the medical instrument <NUM>. In some examples, the control system may compare the shape of the imaging probe <NUM> to the shape of the medical instrument <NUM> to determine the insertion distance of the imaging probe <NUM> relative to the medical instrument <NUM>. For example, the control system may determine how far the imaging probe <NUM> is extended beyond the distal end <NUM> of the medical instrument <NUM>. Additionally or alternatively, based on shape data received from the shape sensor of the imaging probe <NUM>, the control system may determine the pitch and/or the yaw of the imaging probe <NUM>.

In some examples, a proximal end of the imaging probe <NUM> may include a transmission mechanism that allows for finer adjustment of the insertion distance of the imaging probe <NUM>. For example, the transmission mechanism may allow for larger insertion movements at the proximal end of the imaging probe <NUM> to translate to smaller insertion movements at the distal end of the imaging probe <NUM>. For example, if the proximal end of the imaging probe <NUM> is inserted <NUM>, the distal end of the imaging probe <NUM> may be inserted <NUM>. Any other insertion distance ratio may be achieved by the transmission mechanism.

Additionally or alternatively, the user may insert the imaging probe <NUM> by a known insertion distance. The control system may receive an input from the user (e.g., via the GUI <NUM>) inputting the insertion distance. Additionally or alternatively, the control system may provide instructions to the user to insert the imaging probe <NUM> by a specified distance, such as <NUM>, <NUM>, <NUM>, or any other distance. In such examples, the insertion distance may be known by the control system but may still be determined/confirmed by the control system using any one or more of the methods discussed above.

In examples when the control system provides instructions to the user to insert the imaging probe <NUM> by a small distance (e.g., <NUM>, <NUM>, <NUM>), the imaging probe <NUM> may not bend or may experience negligible bending when the imaging probe <NUM> is extended from the medical instrument <NUM>. In such examples, the control system may determine that there is no bending in the imaging probe <NUM>. For example, the control system may determine that a longitudinal axis of the imaging probe <NUM> is substantially parallel with a longitudinal axis of the medical instrument <NUM> when the imaging probe <NUM> is extended from the medical instrument <NUM>. In some alternative examples when the imaging probe <NUM> may be bent a negligible amount, the control system may determine the amount of bending in the imaging probe <NUM> using any one or more of the methods discussed above.

As discussed above, the control system may determine the position of the medical instrument <NUM> within the anatomical passageways <NUM>. Based on this position information, the control system may determine in which anatomical passageway <NUM> the medical instrument <NUM> is positioned. In some examples, the control system may determine the shape of a portion of the anatomical passageway <NUM> within which the medical instrument <NUM> is positioned that is more distal than the portion of the anatomical passageway <NUM> within which the medical instrument <NUM> is positioned. Additionally or alternatively, the control system may determine the shape of any one or more anatomical passageways extending distally of the anatomical passageway <NUM> within which the medical instrument <NUM> is positioned. For example, the control system may analyze the model of the patient anatomy that was generated based on preoperative imaging data, as discussed above. Based on the knowledge of the distally extending anatomical passageway(s), the control system may predict how the imaging probe <NUM> will bend when the imaging probe <NUM> is extended out from the medical instrument <NUM>. In some examples, the control system may predict how the imaging probe <NUM> will bend to assist with identifying the orientation of the imaging plane (e.g., by identifying the orientation of the imaging probe <NUM>).

When the imaging probe <NUM> is extended from the medical instrument <NUM>, the imaging probe <NUM> may bend toward a path of least resistance, which may be a path that most closely follows a flow of fluid through the anatomical passageways. In some examples, the anatomical passageway <NUM> may include a branch point, such as a carina, at the distal end of the anatomical passageway <NUM>. In some examples, the branch point may separate two anatomical passageways. If the medical instrument <NUM> is oriented toward one of the anatomical passageways, the control system may predict that the imaging probe <NUM> will bend toward that anatomical passageway when the imaging probe <NUM> is extended from the medical instrument <NUM>. If the medical instrument <NUM> is oriented toward the other anatomical passageway, the control system may predict that the imaging probe <NUM> will bend toward that anatomical passageway when the imaging probe <NUM> is extended from the medical instrument <NUM>.

With reference to <FIG>, a target adjustment procedure may be initiated when the control system receives a user input selecting a "Place" icon <NUM> in the icon menu <NUM> of the GUI <NUM>. The target adjustment procedure may use the intraoperative imaging data received from the imaging probe <NUM> to adjust the position of the target <NUM> in the virtual navigation view <NUM>, as discussed above with respect to process <NUM> of <FIG>.

In some examples, the components discussed above may be part of a robotic-assisted system as described in further detail below. The robotic-assisted system may be suitable for use in, for example, surgical, robotic-assisted surgical, diagnostic, therapeutic, or biopsy procedures. While some examples are provided herein with respect to such procedures, any reference to medical or surgical instruments and medical or surgical methods is non-limiting. The systems, instruments, and methods described herein may be used for animals, human cadavers, animal cadavers, portions of human or animal anatomy, non-surgical diagnosis, as well as for industrial systems and general robotic, general robotic-assisted, or robotic medical systems.

As shown in <FIG>, a medical system <NUM> generally includes a manipulator assembly <NUM> for operating a medical instrument <NUM> (e.g., the medical instrument <NUM>) in performing various procedures on a patient P positioned on a table T. The manipulator assembly <NUM> may be robotic-assisted, non-robotic-assisted, or a hybrid robotic-assisted and non-robotic-assisted assembly with select degrees of freedom of motion that may be motorized and/or robotic-assisted and select degrees of freedom of motion that may be non-motorized and/or non-robotic-assisted. The medical system <NUM> may further include a master assembly <NUM>, which generally includes one or more control devices for controlling manipulator assembly <NUM>. Manipulator assembly <NUM> supports medical instrument <NUM> and may optionally include a plurality of actuators or motors that drive inputs on medical instrument <NUM> in response to commands from a control system <NUM>. The actuators may optionally include drive systems that when coupled to medical instrument <NUM> may advance medical instrument <NUM> into a naturally or surgically created anatomic orifice.

Medical system <NUM> also includes a display system <NUM> for displaying an image or representation of the surgical site and medical instrument <NUM> generated by sub-systems of sensor system <NUM>. Display system <NUM> and master assembly <NUM> may be oriented so operator O can control medical instrument <NUM> and master assembly <NUM> with the perception of telepresence. Additional information regarding the medical system <NUM> and the medical instrument <NUM> may be found in International Application Publication No. <CIT>, entitled "Graphical User Interface for Monitoring an Image-Guided Procedure,".

In some examples, medical instrument <NUM> may include components of an imaging system (discussed in more detail below), which may include an imaging scope assembly or imaging instrument that records a concurrent or real-time image of a surgical site and provides the image to the operator or operator O through one or more displays of medical system <NUM>, such as one or more displays of display system <NUM>. The concurrent image may be, for example, a two or three-dimensional image captured by an imaging instrument positioned within the surgical site. In some examples, the imaging system includes endoscopic imaging instrument components that may be integrally or removably coupled to medical instrument <NUM>. However, in some examples, a separate endoscope, attached to a separate manipulator assembly may be used with medical instrument <NUM> to image the surgical site. In some examples, as described in detail below, the imaging instrument alone or in combination with other components of the medical instrument <NUM> may include one or more mechanisms for cleaning one or more lenses of the imaging instrument when the one or more lenses become partially and/or fully obscured by fluids and/or other materials encountered by the distal end of the imaging instrument. In some examples, the one or more cleaning mechanisms may optionally include an air and/or other gas delivery system that is usable to emit a puff of air and/or other gasses to blow the one or more lenses clean. Examples of the one or more cleaning mechanisms are discussed in more detail in International Application Publication No. <CIT>, entitled "Systems and Methods for Cleaning an Endoscopic Instrument"; <CIT>, entitled "Devices, Systems, and Methods Using Mating Catheter Tips and Tools"; and <CIT>, entitled "Systems and Methods for Cleaning an Endoscopic. The imaging system may be implemented as hardware, firmware, software or a combination thereof which interact with or are otherwise executed by one or more computer processors, which may include the processors of the control system <NUM>.

Control system <NUM> includes at least one memory and at least one computer processor (not shown) for effecting control between medical instrument <NUM>, master assembly <NUM>, sensor system <NUM>, and display system <NUM>. Control system <NUM> also includes programmed instructions (e.g., a non-transitory machine-readable medium storing the instructions) to implement some or all of the methods described in accordance with aspects disclosed herein, including instructions for providing information to display system <NUM>.

<FIG> is a simplified diagram of a medical instrument system <NUM> according to some examples. Medical instrument system <NUM> includes elongate device <NUM>, such as a flexible catheter (e.g., the outer catheter <NUM>), coupled to a drive unit <NUM>. Elongate device <NUM> includes a flexible body <NUM> having proximal end <NUM> and distal end or tip portion <NUM>. Medical instrument system <NUM> further includes a tracking system <NUM> for determining the position, orientation, speed, velocity, pose, and/or shape of distal end <NUM> and/or of one or more segments <NUM> along flexible body <NUM> using one or more sensors and/or imaging devices as described in further detail below.

Tracking system <NUM> may optionally track distal end <NUM> and/or one or more of the segments <NUM> using a shape sensor <NUM>. Shape sensor <NUM> may optionally include an optical fiber aligned with flexible body <NUM> (e.g., provided within an interior channel (not shown) or mounted externally). The optical fiber of shape sensor <NUM> forms a fiber optic bend sensor for determining the shape of flexible body <NUM>. In one alternative, optical fibers including Fiber Bragg Gratings (FBGs) are used to provide strain measurements in structures in one or more dimensions. Various systems and methods for monitoring the shape and relative position of an optical fiber in three dimensions are described in <CIT>, entitled "Fiber Optic Position and Shape Sensing Device and Method Relating Thereto"; <CIT>, entitled "Fiber-Optic Shape and Relative Position Sensing"; and <CIT>, entitled "Optical Fibre Bend Sensor". Sensors in some examples may employ other suitable strain sensing techniques, such as Rayleigh scattering, Raman scattering, Brillouin scattering, and Fluorescence scattering. In some examples, the shape of the elongate device may be determined using other techniques. For example, a history of the distal end pose of flexible body <NUM> can be used to reconstruct the shape of flexible body <NUM> over the interval of time. In some examples, tracking system <NUM> may optionally and/or additionally track distal end <NUM> using a position sensor system <NUM>. Position sensor system <NUM> may be a component of an EM sensor system with position sensor system <NUM> including one or more conductive coils that may be subjected to an externally generated electromagnetic field. Each coil of the EM sensor system then produces an induced electrical signal having characteristics that depend on the position and orientation of the coil relative to the externally generated electromagnetic field. In some examples, position sensor system <NUM> may be configured and positioned to measure six degrees of freedom, e.g., three position coordinates X, Y, Z and three orientation angles indicating pitch, yaw, and roll of a base point or five degrees of freedom, e.g., three position coordinates X, Y, Z and two orientation angles indicating pitch and yaw of a base point. Further description of a position sensor system is provided in <CIT>, entitled "Six-Degree of Freedom Tracking System Having a Passive Transponder on the Object Being Tracked".

Flexible body <NUM> includes a channel <NUM> sized and shaped to receive a medical instrument <NUM>. Further description of a medical instrument received by a flexible body is provided in <CIT>, entitled "Systems for Coupling and Storing an Imaging Instrument", which is incorporated by reference herein in its entirety.

Flexible body <NUM> may also house cables, linkages, or other steering controls (not shown) that extend between drive unit <NUM> and distal end <NUM> to controllably bend distal end <NUM> as shown, for example, by broken dashed line depictions <NUM> of distal end <NUM>. In some examples, at least four cables are used to provide independent "up-down" steering to control a pitch of distal end <NUM> and "left-right" steering to control a yaw of distal end <NUM>. Steerable elongate devices are described in detail in <CIT>, entitled "Catheter with Removable Vision Probe".

The information from tracking system <NUM> may be sent to a navigation system <NUM> where it is combined with information from image processing system <NUM> and/or the preoperatively obtained models to provide the operator with real-time position information. In some examples, the real-time position information may be displayed on display system <NUM> of <FIG> for use in the control of medical instrument system <NUM>. In some examples, control system <NUM> of <FIG> may utilize the position information as feedback for positioning medical instrument system <NUM>. Various systems for using fiber optic sensors to register and display a surgical instrument with surgical images are provided in <CIT>, entitled "Medical System Providing Dynamic Registration of a Model of an Anatomic Structure for Image-Guided Surgery,".

In some examples, medical instrument system <NUM> may be robotic-assisted within medical system <NUM> of <FIG>. In some examples, manipulator assembly <NUM> of <FIG> may be replaced by direct operator control. In some examples, the direct operator control may include various handles and operator interfaces for hand-held operation of the instrument.

The singular forms "a", "an", and "the" are intended to include the plural forms as well, unless the context indicates otherwise. And the terms "comprises," "comprising," "includes," "has," and the like specify the presence of stated features, steps, operations, elements, and/or components but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups. Components described as coupled may be electrically or mechanically directly coupled, or they may be indirectly coupled via one or more intermediate components. The auxiliary verb "may" likewise implies that a feature, step, operation, element, or component is optional.

In the description, specific details have been set forth describing some embodiments. Numerous specific details are set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art that some embodiments may be practiced without some or all of these specific details. The specific embodiments disclosed herein are meant to be illustrative but not limiting. One skilled in the art may realize other elements that, although not specifically described here, are within the scope and the spirit of this disclosure.

Elements described in detail with reference to one example, implementation, or application optionally may be included, whenever practical, in other examples, implementations, or applications in which they are not specifically shown or described. For example, if an element is described in detail with reference to one example and is not described with reference to a second example, the element may nevertheless be claimed as included in the second example. Thus, to avoid unnecessary repetition in the following description, one or more elements shown and described in association with one example, implementation, or application may be incorporated into other examples, implementations, or aspects unless specifically described otherwise, unless the one or more elements would make an example or implementation non-functional, or unless two or more of the elements provide conflicting functions.

Any alterations and further modifications to the described devices, instruments, methods, and any further application of the principles of the present disclosure are fully contemplated as would normally occur to one skilled in the art to which the disclosure relates. In addition, dimensions provided herein are for specific examples and it is contemplated that different sizes, dimensions, and/or ratios may be utilized to implement the concepts of the present disclosure. To avoid needless descriptive repetition, one or more components or actions described in accordance with one illustrative embodiment can be used or omitted as applicable from other illustrative embodiments. For the sake of brevity, the numerous iterations of these combinations will not be described separately. For simplicity, in some instances the same reference numbers are used throughout the drawings to refer to the same or like parts.

The systems and methods described herein may be suited for navigation and treatment of anatomic tissues, via natural or surgically created connected passageways, in any of a variety of anatomic systems, including the lung, colon, the intestines, the kidneys and kidney calices, the brain, the heart, the circulatory system including vasculature, and/or the like. Although some of the examples described herein refer to surgical procedures or instruments, or medical procedures and medical instruments, the techniques disclosed apply to non-medical procedures and non-medical instruments. For example, the instruments, systems, and methods described herein may be used for non-medical purposes including industrial uses, general robotic uses, and sensing or manipulating non-tissue work pieces. Other example applications involve cosmetic improvements, imaging of human or animal anatomy, gathering data from human or animal anatomy, and training medical or non-medical personnel. Additional example applications include use for procedures on tissue removed from human or animal anatomies (without return to a human or animal anatomy), and performing procedures on human or animal cadavers. Further, these techniques can also be used for surgical and nonsurgical medical treatment or diagnosis procedures.

Further, although some of the examples presented in this disclosure discuss robotic-assisted systems or remotely operable systems, the techniques disclosed are also applicable to computer-assisted systems that are directly and manually moved by operators, in part or in whole.

Additionally, one or more elements in examples of this disclosure may be implemented in software to execute on a processor of a computer system such as a control processing system. When implemented in software, the elements of the examples of the present disclosure are essentially the code segments to perform the necessary tasks. The program or code segments can be stored in a processor readable storage medium (e.g., a non-transitory storage medium) or device that may have been downloaded by way of a computer data signal embodied in a carrier wave over a transmission medium or a communication link. The processor readable storage device may include any medium that can store information including an optical medium, semiconductor medium, and magnetic medium. Processor readable storage device examples include an electronic circuit, a semiconductor device, a semiconductor memory device, a read only memory (ROM), a flash memory, an erasable programmable read only memory (EPROM); a floppy diskette, a CD-ROM, an optical disk, a hard disk, or other storage device. The code segments may be downloaded via computer networks such as the Internet, Intranet, etc. Any of a wide variety of centralized or distributed data processing architectures may be employed. Programmed instructions may be implemented as a number of separate programs or subroutines, or they may be integrated into a number of other aspects of the systems described herein. In some examples, the control system may support wireless communication protocols such as Bluetooth, Infrared Data Association (IrDA), HomeRF, IEEE <NUM>, Digital Enhanced Cordless Telecommunications (DECT), ultra-wideband (UWB), ZigBee, and Wireless Telemetry.

A computer is a machine that follows programmed instructions to perform mathematical or logical functions on input information to produce processed output information. A computer includes a logic unit that performs the mathematical or logical functions, and memory that stores the programmed instructions, the input information, and the output information. The term "computer" and similar terms, such as "processor" or "controller" or "control system", are analogous.

Note that the processes and displays presented may not inherently be related to any particular computer or other apparatus, and various systems may be used with programs in accordance with the teachings herein. The required structure for a variety of the systems discussed above will appear as elements in the claims. In addition, the examples of the present disclosure are not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of the present disclosure as described herein.

Claim 1:
A medical system comprising:
an elongate device;
an elongate sheath configured to extend within the elongate device, the elongate sheath including an identification feature;
an imaging probe configured to extend within the elongate sheath; and
a control system configured to:
receive imaging data from the imaging probe, the imaging data being captured by the imaging probe;
analyze the imaging data to identify an appearance of the identification feature within the imaging data; and
based on the appearance of the identification feature, register the imaging data to a reference frame of the elongate device.