Imaging orientation planning for external imaging devices

Abstract

Methods and systems are disclosed for forming one or more projected two-dimensional images based on computed tomography (CT) data of a subject, a planned pose of a flexible elongate device, and one or more parameters of an external imaging device. In some examples, one or more projected two-dimensional images may be used to determine an appropriate imaging orientation of an external imaging device used during a medical procedure.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to and the benefit of U.S. Provisional Application No. 63 / 409,310, filed on September 23, 2022, entitled “Imaging Orientation Planning for External Imaging Devices,” the entire contents of which are incorporated herein by reference. Technical Field

[0003] Disclosed examples relate to imaging orientation planning for external imaging devices and related systems. Background Art

[0004] A C-arm fluoroscope is commonly used to perform X-ray examinations of a patient on a patient platform. Depending on the procedure being performed, a medical practitioner can reorient the C-arm from a number of different orientations during the medical procedure to view the subject's internal tissues and / or organs, and in some cases, flexible, elongated devices positioned within the subject's anatomy. This can help the medical practitioner determine the relative position and orientation of different tissues and flexible, elongated devices during the medical procedure. Summary of the invention

[0005] In some examples, a method includes: obtaining computed tomography (CT) data of a subject, wherein the CT data includes target tissue of the subject; obtaining a planned pose of a flexible, elongated device within the anatomical structure of the subject; and forming one or more projected two-dimensional images based on the CT data, the planned pose of the flexible, elongated device, and one or more parameters of an external imaging device.

[0006] In some examples, a non-transitory computer-readable memory includes instructions that, when executed by one or more processors, perform the above-described methods.

[0007] In some examples, a medical procedure planning device includes: a processor; and a non-transitory computer readable memory storing computer executable instructions that, when executed by the processor, cause the device to: obtain computed tomography (CT) data of a subject, wherein the CT data includes target tissue of the subject; obtain a planned pose of a flexible, elongated device within the anatomical structure of the subject; and determine one or more imaging orientations of an external imaging device for use during the medical procedure based on the CT data, the planned pose of the flexible, elongated device, and one or more parameters of the external imaging device.

[0008] It should be understood that the above concepts and the additional concepts discussed below can be arranged in any suitable combination, as the present disclosure is not limited in this regard. In addition, other advantages and novel features of the present disclosure will become apparent through the following detailed description of various non-limiting examples when considered in conjunction with the accompanying drawings.

[0009] If this specification and the document incorporated by reference include conflicting and / or inconsistent disclosures, this specification shall prevail. If two or more documents incorporated by reference include conflicting and / or inconsistent disclosures, the document with the later effective date shall prevail. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in various figures may be represented by the same numeral. For clarity, not every component may be labeled in every drawing. In the drawings:

[0011] Figure 1 is a schematic diagram of an illustrative teleoperated medical system according to an example of the present disclosure.

[0012] Figure 2A A medical device system according to an example of the present disclosure is shown.

[0013] Figure 2B A distal portion of a medical device system according to an example of the present disclosure is shown.

[0014] Figure 3 is an illustration of operating an external imaging device with a subject in position according to an example of the present disclosure.

[0015] Figure 4A is a schematic representation of a detector and a source of an external imaging device in a first orientation relative to an object according to an example of the present disclosure.

[0016] Figure 4B The detector and source of the external imaging device according to an example of the present disclosure are in a second orientation relative to Figure 4A Schematic representation of an object.

[0017] Figure 5 is a flow chart of a method for determining an imaging orientation for use during a medical procedure according to an example of the present disclosure.

[0018] FIG. 6A to FIG. 6B An example of forming a projected two-dimensional image at two different orientations using previously acquired external imaging data according to an example of the present disclosure is depicted.

[0019] 7A to 7C Depicted are computed tomography (CT) data of a subject's torso viewed from different orientations according to examples of the present disclosure.

[0020] Fig. 8A Depicting computed tomography (CT) data of a subject's torso with a planned pose of a flexible elongated device and locations of target tissue contained in the CT data according to examples of the present disclosure.

[0021] Figure 8B According to the example of the present disclosure Fig. 8A Projected 2D view of CT data.

[0022] Fig.9A is a projected two-dimensional image including the flexible elongated device and the target tissue as viewed from a first orientation, and wherein a minimal border region surrounds the flexible elongated device.

[0023] Fig. 9B Observed from the second orientation Fig.9A A projected two-dimensional image of the flexible elongated device and the target tissue, wherein a minimal border area surrounds the flexible elongated device. DETAILED DESCRIPTION

[0024] C-arm fluoroscopes can be used to provide fluoroscopic imaging of subjects in various medical procedures including, for example, interventional pulmonary procedures. During such procedures, a medical practitioner may desire to position the distal portion of a flexible, elongated device (such as a catheter and / or endoscope or other suitable flexible, elongated device) in a desired posture in order to interact with a target tissue. Since a C-arm fluoroscope typically presents a real-time two-dimensional X-ray image of a subject, it may be difficult for a medical practitioner to determine the relative posture of the flexible, elongated device and the target tissue in three-dimensional space. Therefore, during the procedure, a medical practitioner may move a C-arm fluoroscope or other external imaging device between multiple orientations relative to the subject to ensure the proper positioning and orientation of the flexible, elongated device during the procedure. Since a medical practitioner typically does not know which imaging orientations need to be observed to determine the relative posture of the flexible, elongated device and the target tissue, the medical practitioner may observe the subject at multiple imaging orientations. This may increase the overall X-ray dose delivered to the subject during the procedure.

[0025] In view of the foregoing, the inventors have recognized the desire to reduce the X-ray dose to which a subject is exposed during a procedure. Accordingly, the inventors have recognized the benefits associated with determining an appropriate imaging orientation of an external imaging device used to observe a flexible, elongated device and target tissue within a subject prior to performing a medical procedure. By finding an appropriate viewing orientation prior to performing a medical procedure, a medical practitioner may not need to manually search for an optimal imaging orientation in real time during a procedure, which may result in a reduction in X-ray dose compared to a typical unplanned procedure.

[0026] In some examples, the appropriate imaging orientation of an external imaging device used during a medical procedure can be determined by forming a projected two-dimensional image using computed tomography (CT) data of the anatomical structure of a subject previously taken. These projected two-dimensional images can correspond to different orientations of the external imaging device relative to the subject. Therefore, before performing the procedure, the relative positioning and orientation of various anatomical structures in the subject and / or the planning posture of the flexible elongated device can be observed and / or otherwise evaluated in these projected two-dimensional images. Therefore, the projected two-dimensional images can be used to determine the appropriate imaging orientation of the external imaging device used during the medical procedure. As further elaborated below, this can be manually completed by a medical practitioner based on their observation of the projected two-dimensional images to select the orientation, and / or the appropriate imaging orientation can be determined based at least in part on the analysis of multiple projected two-dimensional images.

[0027] The disclosed methods and systems can be used for any appropriate application. For example, the predetermined imaging orientation can be used for medical procedures associated with any desired anatomical structure of a subject, including but not limited to medical procedures for the lungs, colon, intestines, kidneys, renal calyces, brain, heart, circulatory system including vascular system, and / or any other appropriate type of medical procedures. These medical procedures can also include the use of any appropriate external imaging device that can be moved between different orientations relative to the subject, including but not limited to X-ray imaging devices (such as X-ray fluoroscopes (including C-arm fluoroscopes)) and / or any other appropriate external imaging device capable of imaging the internal anatomical structure of the subject. In addition, the disclosed methods and systems can facilitate medical procedures involving the use of endoscopes, catheters, laparoscopes, and / or any other appropriate flexible, elongated devices that can be used in medical procedures where real-time X-ray imaging can be used.

[0028] As used herein, the orientation of an external imaging device may refer to the orientation of the source and detector of the imaging device relative to the subject during a planned medical procedure. For example, when the imaging device is a C-arm fluoroscope, the orientation of the external imaging device may refer to the C-arm angle, but as described above, other external imaging devices and orientation types may be used.

[0029] In the following description, the specific details of some examples consistent with the present disclosure are described. In order to provide a thorough understanding of the examples, many specific details are proposed. However, it is obvious to those skilled in the art that some examples can be put into practice without some or all of these specific details. The specific examples disclosed herein are intended to be illustrative rather than restrictive. Those skilled in the art may realize other elements, which are also within the scope and spirit of the present disclosure, although not specifically described herein. In addition, in order to avoid unnecessary repetition, one or more features shown and described in association with an example may be incorporated into other examples, unless specifically described otherwise or if one or more features will make the example inoperative.

[0030] In some instances, well-known methods, procedures, components, and circuits have not been described in detail so as not to unnecessarily obscure aspects of the examples.

[0031] The present disclosure describes various apparatuses and parts of apparatuses according to their states in three-dimensional space. As used herein, the term "position" refers to the location of an object or a portion of an object in three-dimensional space (e.g., three translational degrees of freedom along Cartesian x, y, and z coordinates). As used herein, the term "orientation" refers to the rotational placement of an object or a portion of an object (three rotational degrees of freedom - such as roll, pitch, and / or yaw). As used herein, the term "attitude" refers to the position of an object or a portion of an object in at least one translational degree of freedom and the orientation of the object or portion of an object in at least one rotational degree of freedom (up to six total degrees of freedom). As used herein, the term "shape" refers to a set of attitudes, positions, or orientations measured along an object.

[0032] Turning to the drawings, specific non-limiting examples are described in more detail. It should be understood that the various systems, components, features, and methods described with respect to these examples may be used alone and / or in any desired combination, as the present disclosure is not limited to the specific examples described herein.

[0033] Figure 1 is a simplified diagram of a teleoperated medical system 100 according to some examples. In some examples, the teleoperated medical system 100 may be suitable for use in, for example, surgical, diagnostic, therapeutic, or biopsy procedures, in which it may be desirable to provide real-time imaging of the medical procedure being performed. Although some examples of such procedures are provided herein, 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 diagnostics, and industrial systems and general robotic or teleoperated systems.

[0034] like Figure 1 As shown, the medical system 100 generally includes a manipulator assembly 102 for operating a medical device 104 when performing various procedures on a patient P located on a table T. The manipulator assembly 101 can be a remotely operated assembly, a non-remotely operated assembly, or a hybrid remotely operated and non-remotely operated assembly having selected degrees of freedom of movement that can be motorized and / or remotely operated and selected degrees of freedom of movement that can be non-motorized and / or non-remotely operated. The main control assembly 106 generally includes one or more control devices for controlling the manipulator assembly 102. The manipulator assembly 102 supports the medical device 104 and can optionally include a plurality of actuators or motors that drive inputs on the medical device 104 in response to commands from a control system 112. The actuators can optionally include drive systems that, when coupled to the medical device 104, can advance the medical device 104 into a natural or surgically created anatomical hole. Other drive systems can move the distal end of the medical device 104 in multiple degrees of freedom, which can include three degrees of freedom for linear motion (e.g., linear motion along the X, Y, Z Cartesian axes) and three degrees of freedom for rotational motion (e.g., rotation about the X, Y, and Z Cartesian axes). In addition, the actuator can be used to actuate an articulated end effector of the medical device 104 for grasping tissue in the jaws of a biopsy device, etc. Actuator position sensors (such as rotary transformers, encoders, potentiometers, and other mechanisms) can provide sensor data describing the rotation and orientation of the motor shaft to the medical system 100. This position sensor data can be used to determine the motion of an object manipulated by the actuator.

[0035] The teleoperated medical system 100 also includes a display system 110 for displaying images or representations of the surgical site and medical instrument 104 generated by the subsystems of the sensor system 108. The display system 110 and the master control assembly 106 can be oriented so that the operator O can control the medical instrument 104 and the master control assembly 104 using the perception of the telepresentation.

[0036] In some examples, the medical device 104 may include a component of an imaging device, which may include an imaging scope assembly or an imaging instrument that records concurrent or real-time images of a medical site and provides the images to an operator or operator O through one or more displays of the medical system 100 (such as one or more displays of the display system 110). The concurrent image can be, for example, a two-dimensional or three-dimensional image captured by an imaging instrument positioned within the medical site. In some examples, the imaging device includes an endoscopic imaging instrument component that can be integrally or removably coupled to the medical device 104. However, in some examples, a separate endoscope attached to a separate manipulator assembly can be used with the medical device 104 to image the medical site. In some examples, as described in detail below, the imaging instrument alone or in combination with other components of the medical device 104 may include one or more mechanisms for cleaning one or more lenses of the imaging instrument when one or more lenses are partially and / or completely obscured by fluids and / or other materials encountered by the distal end of the imaging instrument. In some examples, one or more cleaning mechanisms may optionally include an air and / or other gas delivery system that can be used to emit a stream of air and / or other gas to blow one or more lenses clean. Examples of one or more cleaning mechanisms are discussed in more detail in the following patent documents: International Publication No. WO / 2016 / 025465 filed on August 11, 2016, which discloses "Systems and Methods for Cleaning an Endoscopic Instrument"; U.S. Patent Application Serial No. 15 / 508,923 filed on March 5, 2017, which discloses "Devices, Systems, and Methods Using Mating Catheter Tips and Tools"; and U.S. Patent Application Serial No. 15 / 503,589 filed on February 13, 2017, which discloses "Systems and Methods for Cleaning an Endoscopic Instrument", each of which is incorporated herein by reference in its entirety. The imaging device may be implemented as hardware, firmware, software, or a combination thereof that interacts with or is otherwise executed by one or more computer processors, which may include a processor of the control system 112 .

[0037] The teleoperation medical system 100 may also include a control system 112. The control system 112 includes at least one memory and at least one computer processor (not shown) for implementing control between the medical device 104, the main control component 106, the sensor system 108, and the display system 110. The control system 112 also includes programming instructions (e.g., a non-transitory fluoroscopic readable medium storing instructions) to implement some or all of the methods described according to the aspects disclosed herein, including instructions for providing information to the display system 110.

[0038] The control system 112 may further optionally include a virtual visualization system to provide navigation assistance to the operator O when controlling the medical device 104 during an image-guided surgical procedure. Virtual navigation using the virtual visualization system may be based on reference to an acquired preoperative or intraoperative dataset of an anatomical passage. The virtual visualization system processes images of the surgical site imaged using imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), fluoroscopy, thermal imaging, ultrasound, optical coherence tomography (OCT), thermal imaging, impedance imaging, laser imaging, nanotube X-ray imaging, etc.

[0039] Figure 2A 2 is a simplified diagram of a medical device system 200 according to some examples. The medical device system 200 includes a flexible elongated body 202, such as a flexible catheter, coupled to a drive unit 204. The flexible elongated body 202 includes a flexible elongated body 216 having a proximal end 217 and a distal end or tip portion 218. The medical device system 200 further includes a tracking system 230 for determining a position, orientation, rate, velocity, posture, and / or shape of the distal end 218 and / or one or more segments 224 along the flexible elongated body 216 using one or more sensors and / or imaging devices, as described in further detail below.

[0040] Tracking system 230 may optionally use shape sensor 222 to track one or more of distal end 218 and / or segments 224. Shape sensor 222 may optionally include an optical fiber aligned with flexible elongated body 216 (e.g., disposed within an internal channel (not shown) or mounted externally). The optical fiber of shape sensor 222 forms an optical fiber bend sensor for determining the shape of flexible elongated body 216. In an alternative, an optical fiber including a fiber Bragg grating (FBG) is used to provide strain measurements in a structure 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 the following patent documents: U.S. Patent Application Serial No. 11 / 180,389 (filed on July 13, 2005) (disclosing "Fiber optic position and shape sensing device and method relating thereto"); U.S. Patent Application Serial No. 12 / 047,056 (filed on July 16, 2004) (disclosing "Fiber-optic shape and relative position sensing"); and U.S. Patent No. 6,389,187 (filed on June 17, 1998) (disclosing "Optical Fiber Bend Sensor"), all of which are incorporated herein by reference in their entirety. In some examples, the sensor can employ other suitable strain sensing techniques, such as Rayleigh scattering, Raman scattering, Brillouin scattering, and fluorescence scattering. In some examples, the shape of the flexible elongated body can be determined using other techniques. For example, the history of the distal posture of the flexible elongated body 216 can be used to reconstruct the shape of the flexible elongated body 216 over a period of time. In some examples, tracking system 230 can optionally and / or additionally use position sensor system 220 to track distal end 218. Position sensor system 220 can be a component of an EM sensor system, wherein position sensor system 200 includes one or more conductive coils that can be subjected to an externally generated electromagnetic field. Each coil of the EM sensor system then generates an induced electrical signal, the characteristics of which depend on the position and orientation of the coil relative to the externally generated electromagnetic field. In some examples, position sensor system 220 can be configured and positioned to measure six degrees of freedom, such as three position coordinates X, Y, Z and three orientation angles of pitch, yaw and roll indicating a base point, or five degrees of freedom, such as three position coordinates X, Y, Z and two orientation angles of pitch and yaw indicating a base point.Further description of position sensor systems is provided in U.S. Patent No. 6,380,732 (filed August 11, 1999) (disclosing "Six-Degree of Freedom Tracking System Having a Passive Transponder on the Object Being Tracked"), which is incorporated herein by reference in its entirety.

[0041] Flexible elongate body 216 includes a channel 221 sized and shaped to receive a medical device 226 . Figure 2B 2 is a simplified diagram of a flexible elongated body 216 with an extended medical device 226 according to some examples. In some examples, the medical device 226 can be used for procedures such as surgery, biopsy, ablation, illumination, irrigation, or suction. The medical device 226 can be deployed through the channel 221 of the flexible elongated body 216 and used at a target site within the anatomical structure. The medical device 226 can include, for example, an image capture probe, a biopsy instrument, a laser ablation fiber, and / or other surgical, diagnostic, or therapeutic tools. The medical device 226 can be used with an imaging device (e.g., an image capture probe) that is also within the flexible elongated body 216. The imaging device can include a cable coupled to a camera for transmitting captured image data. In some examples, the imaging device can be a fiber bundle coupled to an image processing system 231, such as a fiberscope. The imaging device can be single-spectrum or multi-spectrum, for example, capturing image data in one or more of the visible spectrum, infrared spectrum, and / or ultraviolet spectrum. The medical device 226 can advance from the opening of the channel 221 to perform the procedure and then retract into the channel when the procedure is completed. The medical device 226 may be removed from the proximal end 217 of the flexible elongated body 216 , or from another optional instrument port (not shown) along the flexible elongated body 214 .

[0042] The flexible elongated body 216 may also house cables, linkages, or other steering controls (not shown) extending between the drive unit 204 and the distal end 218 to controllably bend the distal end 218, for example, as shown by a dashed line depiction 219 of the distal end 218. In some examples, at least four cables are used to provide independent "up and down" steering to control the pitch of the distal end 218, and to provide "side to side" steering to control the yaw of the distal end 281. Steerable flexible elongated bodies are described in U.S. Patent Application Serial No. 13 / 274,208 (filed on October 14, 2011) (disclosing "Catheter with Removable Vision Probe"), which is incorporated herein by reference in its entirety.

[0043] Information from tracking system 230 may be sent to navigation system 232 where it is combined with information from image processing system 231 and / or preoperatively acquired models to provide real-time position information to the operator. In some examples, the real-time position information may be displayed on a Figure 1 on the display system 110 for controlling the medical device system 200. In some examples, Figure 1 The control system 116 can use the position information as feedback for positioning the medical instrument system 200. Various systems for using fiber optic sensors to align and display surgical instruments and surgical images are provided in U.S. patent application serial number 13 / 107,562, filed on May 13, 2011, disclosing "Medical System Providing Dynamic Registration of a Model of an Anatomic Structure for Image-Guided Surgery", which is incorporated herein by reference in its entirety.

[0044] In some examples, the medical device system 200 may be Figure 1 In some examples, Figure 1 The manipulator assembly 102 of the apparatus may be replaced by direct operator controls. In some examples, the direct operator controls may include various handles and operator interfaces for handheld operation of the apparatus.

[0045] Figure 3 is an illustration of operating an external imaging device with a subject in position according to an example of the present disclosure. In some examples, such an external imaging device may be used with Figures 1 to 2B The medical system 100 and / or the medical device system 200 are used in conjunction to facilitate imaging of a flexible, elongated device while it is positioned within the anatomical structure of a subject. Figure 3 A manual C-arm imaging system is shown as the external imaging device 300 in the depicted example. However, it should be understood that, as previously described, an automated C-arm or other external imaging device may be used. In the depicted example, the external imaging device 300 includes a C-arm 310, a source 314, a detector 316, and a manual handle 312. In some examples, the external imaging device 300 includes a display 330. Figure 3Also shown is an operator 340 operating the manual handle 312 and a subject 350 being scanned by the external imaging device 300. The source 314 and the detector 316 can be rotated around the subject in pairs so that the relative posture between the source 314 and the detector 316 is constant during operation. As described above, the C-arm 310 and the associated detector 316 and the source 314 are rotatable so that they can move through a plurality of different orientations, and in some cases, different postures, relative to the subject 350 or other objects disposed between the source 314 and the detector 316. Therefore, when the operator 340 rotates the C-arm 310 between the initial posture and the final posture, the source 314 and the detector 316 can be used to obtain a sequential stream of X-ray images of the subject 350 at a plurality of orientations relative to the subject 350. As described above, this can correspond to rotations between any desired postures, including rotations over the entire rotation range of the C-arm 310 or over a portion of the rotation range of the C-arm 310.

[0046] In some examples, a medical procedure planning apparatus as described herein may be part of a controller 320 of an external imaging device 100. Alternatively or additionally, the medical procedure planning apparatus may be part of a stand-alone computer, such as a desktop computer, a portable computer, and / or a remote or local server. In some examples, the medical procedure planning apparatus may include at least one processor, such as the controller 320, having associated non-transitory computer-readable memory. The memory may include computer-executable instructions that, when executed by the at least one processor, cause the apparatus to perform any of the methods disclosed herein.

[0047] Figure 4A and Figure 4B A schematic depiction of one example of different orientations of a source 314 and a detector 316 of an external imaging device relative to a subject 350 is shown. As shown, and as described above with respect to Figure 3 Similar to the example described above, source 314 and detector 316 are disposed on opposite sides of subject 350, with a predetermined constant posture between source 314 and detector 316. Figure 4A , the source 314 and detector 316 of the external imaging device are oriented in a vertical orientation, which may be referred to as a 0° orientation relative to the vertical axis of the system. In some examples, the vertical axis of the system may correspond to the direction of local gravity relative to the system. Figure 4B , source 314 and detector 316 have been rotated through angle θ relative to the vertical axis of the system such that source 314 and detector 316 are rotated from a first orientation relative to subject 350 to a different second orientation to observe subject 350 from a different angle.

[0048] Figure 5An example of a method for pre-planning imaging orientations for use with an external imaging device during a medical procedure performed on a subject is depicted. In the depicted method, at step 400, external imaging data (e.g., computed tomography (CT) data, MRI data, ultrasound data, etc.) associated with the subject can be obtained. For example, the external imaging data can correspond to a preoperative CT scan for diagnostic and / or planning purposes, and can be obtained by a medical practitioner using a CT scanner (not depicted). Depending on the specific example, the resulting external imaging data can be immediately processed using the methods disclosed herein, and / or stored in a non-transitory computer-readable memory for future recall and use. Depending on the procedure to be performed, the external imaging data can correspond to three-dimensional information of anatomical structures and tissues within parts of the subject's body (including but not limited to the subject's torso, limbs, head, or other appropriate parts of the body).

[0049] At 402, one or more parameters associated with an external imaging device used during a medical procedure may be obtained. These parameters may be pre-stored in a non-transitory computer-readable memory for subsequent recall, manually input by a user, and / or automatically downloaded from an associated external imaging device, as the present disclosure is not limited in this manner. In any case, one or more parameters may correspond to parameters associated with how the external imaging device captures an image of the subject. For example, appropriate parameters may include, but are not limited to, device geometry, source intensity, relative spacing and / or orientation (e.g., posture) of a source and detector of an external imaging device, a range of motion of an external imaging device, a position of an X-ray source and detector relative to the subject, a camera distortion matrix, an image noise level, and / or any other appropriate parameter associated with an imaging device.

[0050] In order to facilitate determining the planning posture of the flexible elongated device relative to the target tissue during one or more stages of the medical procedure, it may be desirable to generate a model of the anatomical structure of the subject. Therefore, in some examples, the external imaging data obtained can be segmented and modeled at 404. The resulting model can correspond to a model of one or more parts of the anatomical structure of the subject. For example, the model can correspond to a model of the lungs of a subject undergoing a pulmonary procedure. At 405, using the model and the site of the target tissue in the subject, the planning path of the insertion and operation of the flexible elongated device can be determined for one or more parts of the medical procedure. This can include determining a path through one or more modeled parts of the anatomical structure of the subject, the path from the entry site (such as a natural or artificial orifice formed in the subject's body) to the site of the adjacent target tissue in the subject's body. For example, the planning posture of the flexible elongated device can extend from the oral cavity through the esophagus to the site of the adjacent target tissue in the lung of the subject. Depending on the specific example, the planning posture can be manually determined by the practitioner and / or can be automatically generated by an appropriate path planning software module, because the present invention is not limited to this. In some examples, the external imaging (e.g., CT) data can be updated to include information related to the planning posture of the flexible elongated device. For example, the model and the planning pose can be used to update the intensity of voxels included in the external imaging data corresponding to the planning pose. For example, the intensity of voxels (e.g., CT data) corresponding to the planning pose of the flexible, elongated device during the medical procedure can be increased. In some examples, this can include increasing the intensity of these voxels to the maximum intensity associated with the external imaging data, or other appropriately large intensities to provide high contrast relative to adjacent tissues, as desired for a metal shaft of a flexible, elongated device inserted into a subject's anatomy during X-ray imaging.

[0051] Examples of segmentation, model generation, and path planning for medical procedures using external imaging data are described in International Patent Application WO 2018 / 195221, which is incorporated herein by reference in its entirety. However, it should be understood that any suitable method may be used to determine the planned pose of the flexible elongated device within the anatomy of the subject, including, for example, a manual path planning process.

[0052] In some examples, once the external imaging (eg, CT) data is updated with the planned pose of the flexible elongated device, one or more projected two-dimensional images, and in some cases multiple projected two-dimensional images, may be generated at 406. FIG. 6A to FIG. 6B, where a simulated source 500 is virtually positioned at a known location and orientation (i.e., pose) relative to a simulated receiver 504 of an external imaging device to be used. The relative pose of the source 500 and the receiver 504 can be determined based on the parameters of the external imaging device. The three-dimensional voxels of the external imaging (e.g., CT) data 502 can be virtually positioned at an expected location and pose relative to the virtual source 500 and the detector 504. As described in detail below, the pose of the virtual source 500 and the detector 504 relative to the external imaging data 502 can be used to generate a projected two-dimensional image that corresponds to the plane in which the virtual detector 504 is located, as described in detail below. This process is described in detail below. Fig. 6A , and may be repeated for any number of different orientations or postures, such as Figure 6B A second orientation of the virtual source 500 and the virtual detector 504 is shown relative to the external imaging data 502. For example, a plurality of projected two-dimensional images may be formed at different orientations that are evenly or non-evenly distributed within the range of motion of the external imaging device.

[0053] In some examples, FIG. 6A to FIG. 6B The depicted projected two-dimensional images may be formed using methods such as digital reconstruction of radiographic images. Such an algorithm may use one or more of the external imaging device parameters described above and the relative poses of the virtual source 500 and detector 504 with respect to the external imaging data 502 to generate one or more projected two-dimensional images. When generating the projected two-dimensional images, the algorithm may calculate a straight line (ray) from the source 500 to each pixel on the detector 504 based on the 3D coordinates, see Fig. 6A and Figure 6B. The algorithm may then trace each point (e.g., voxel) along each ray to see if it intersects the three-dimensional volume of external imaging data 502. If the ray intersects one or more voxels of the external imaging data, it will obtain an intensity value (e.g., a Hounsfield unit (HU) value) for that particular voxel and convert the intensity value into an attenuation coefficient. The algorithm may sum the attenuation coefficients determined along each ray associated with an independent pixel of the virtual detector, and the resulting summed attenuation coefficient may be used as the intensity value of the pixel of the detector associated with that particular ray. By performing this calculation for each pixel of the virtual detector 504, a final projected two-dimensional image may be generated. As previously described, this process may be performed for any number of different orientations of the virtual source and detector relative to the three-dimensional volume of external imaging data 502 to provide multiple projected two-dimensional images associated with different orientations of the external imaging device. For example, projected two-dimensional images may be generated for different orientations within a portion of the range of motion and / or the entire range of motion of the external imaging device. In one such example, the external imaging device can be a C-arm fluoroscope, and the multiple different orientations can correspond to multiple different C-arm angles, which can be evenly distributed or non-evenly distributed within the range of motion of the C-arm. Of course, it should be understood that different types of external imaging devices can also be used.

[0054] It should be appreciated that although a particular method of generating a projected two-dimensional image using external imaging data has been described above, any suitable method may be used to generate a projected two-dimensional image.

[0055] In some examples, it may be desirable to display multiple two-dimensional images to a user, see Figure 5 408 in step 408. For example, the images may optionally be displayed sequentially to the user, wherein the projected two-dimensional images may sequentially progress from a first posture and / or orientation to a final posture and / or orientation along the range of motion of the external imaging device. In one such example, the sequential projected two-dimensional images may correspond to C-arm angles of a C-arm fluoroscope, ranging from 0° to a maximum C-arm angle. Regardless, the multiple projected two-dimensional images may be displayed to the user in any appropriate manner, including but not limited to video sequences, manually scrolling sequential image stacks, and / or any other appropriate type of presentation. In addition, as described below with respect to Fig. 8A and Figure 8B As further described, the image may include various types of information for the user to view, including but not limited to the planned pose of the flexible elongated device, the location of the target tissue (e.g., lesions, tumors, or other desired target tissue) within the projected image, and / or any other appropriate information. In some examples, to further emphasize the location of the target tissue with the image, the software may overlay the target tissue on the projected two-dimensional image.

[0056] At 410, one or more orientations may be selected for use during a medical procedure. One or more orientations may be selected in any suitable manner. For example, in one example, a user may manually select one or more imaging orientations by manually selecting one or more of a plurality of projected two-dimensional images. Alternatively, one or more orientations may be selected based on one or more suitable criteria evaluated by an associated selection algorithm. Examples of suitable methods for selecting one or more imaging orientations are provided below.

[0057] In one example, one or more orientations can be selected based at least in part on the curvature of the simulated flexible elongated device 604 within the projected two-dimensional image (e.g., the curvature of a catheter or endoscope along a planned path). In one such example, a minimum bounding area 616 of the projected two-dimensional curve of the flexible elongated device 604 in the projection plane can be used to determine the desired imaging orientation. For example, Fig.9A and Fig. 9B As shown, a minimum boundary area 616 surrounding the flexible elongated device 604 can be determined for each projected two-dimensional image. Fig.9A 616 in which the flexible elongated device 604 and the target tissue 602 overlap within the projected two-dimensional image, as compared to Fig. 9B In another example, the cumulative curvature of the flexible elongated device 604 can be determined for each projected two-dimensional image by summing the curvature along the projected planning pose of the flexible elongated device 604 in each image. Fig.9A and Fig. 9B As shown, the total curvature along the length of the flexible elongated device 604 in the projected two-dimensional image is Fig. 9B is larger in the projection planning pose of the target tissue 602 and the flexible elongated device 602, where the relative pose of the target tissue 602 and the flexible elongated device 602 can be more easily observed. Therefore, after determining the minimum bounding area and / or cumulative curvature, the projected two-dimensional image with the minimum bounding area and / or maximum value of the accumulated curvature for the projected planning pose of the flexible elongated device in the image can be selected for the proposed imaging orientation during the procedure.

[0058] In another example, the geometric relationship between the projected flexible elongated device and the target tissue in the projected two-dimensional image can be used to select an orientation to be used during a medical procedure. For example, in some examples, for each of the plurality of projected images, a distance D corresponding to a separation distance between the distal portion of the flexible elongated device 604 in the planned pose and the target tissue 602 within the projected two-dimensional image can be determined, e.g. Figure 8B The projected two-dimensional image having the minimum separation distance between the distal portion of the flexible elongated device 604 in the planning posture and the target tissue 602 may then be selected.

[0059] In yet another example, the visibility of the target tissue in multiple two-dimensional projection images can be used to determine one or more imaging orientations used during a medical procedure. In some such examples, the target area can correspond to a tissue area including the target tissue. For example, the size of the target area can be about 2 to 3 times the size of the target tissue, and can be juxtaposed with the target tissue. The target area can include both the target tissue and the tissue around the target tissue. The target area can be appropriately registered with the target tissue in the external imaging data, and can also be included in the subsequently generated projection two-dimensional image. Then, various metrics related to the visibility of the improved target tissue relative to other anatomical structures can be used to select one or more orientations used during a medical procedure. For example, appropriate metrics can include but are not limited to signal-to-noise ratio (e.g., the contrast ratio between the target tissue and surrounding tissue in the target area), the ratio of the mean value of the pixels in the target area to the standard deviation of the pixel value, the total change of the image gradient in the target area, structural similarity (SSIM) and / or any other appropriate metrics for selecting one or more imaging orientations based on the analysis of multiple projection two-dimensional images.

[0060] In another example, the geometric relationship between the projected target tissue relative to one or more projected bone structures or other highly visible structures within the plurality of projected two-dimensional images can be used to select one or more imaging orientations for use during a medical procedure. For example, a separation distance B corresponding to a minimum distance between the target tissue and the one or more bone structures within the plurality of projected two-dimensional images can be determined for each image, see Figure 8B . The threshold intensity can be used, at least in part, to help identify bone structures or other highly visible structures in multiple projected two-dimensional images. For example, the pixel intensity in the projected two-dimensional image can be compared to the threshold intensity, and pixels with intensities greater than the threshold intensity can be identified as bone structures or other similar anatomical structures that may interfere with the visualization of the target tissue. However, other appropriate methods can also be used to determine the minimum distance. The minimum separation distance between the target tissue and one or more identified bone structures can then be identified for each of the multiple projected two-dimensional images. One or more orientations can then be selected based on the determined spacing between the target tissue and one or more bone structures within the projected two-dimensional image. For example, the orientation corresponding to the projected two-dimensional image with the largest minimum spacing can correspond to the orientation in which the target tissue is least obstructed by surrounding bone structures.

[0061] Although several methods for automatically determining one or more imaging orientations for use with an external imaging device during a medical procedure are provided above, it should be understood that these methods may be used in combination with each other, used alone, and / or other appropriate methods for determining one or more imaging orientations may be used. In addition, in some examples, the system may automatically determine the recommended imaging orientation using the methods described above without user intervention. However, in other examples, the software may recommend a recommended orientation for use during a medical procedure to the user for review and approval. This can include, for example, displaying the orientation and corresponding projected two-dimensional image to the user on a display for approval. The recommended imaging orientation of the external imaging device may be displayed to the medical practitioner in any appropriate manner, including but not limited to a digital output, a visual output such as an orientation icon, a combination of the above, and / or any other appropriate type of indication. For example, see Figure 8B , an orientation icon 612 shown in . In some examples, indications regarding one or more medical activities associated with one or more suggested imaging orientations may also be displayed to the medical practitioner. This may include displaying an appropriate icon and / or text to indicate the medical activity. For example, a first set of suggested imaging orientations may be proposed for a first medical activity, and a second set of suggested imaging orientations may be proposed for a second medical activity, where the optimal viewing angle may be different. After the suggested imaging orientations have been presented to the user, the user may then manually select one or more of the suggested orientations to include in the medical planning.

[0062] After selecting one or more orientations, the one or more selected imaging orientations may then be used to update the plan at 412. For example, the selected one or more imaging orientations for use with the external imaging device may be stored on a non-transitory computer-readable memory along with the updated plan for future recall, for reference purposes and / or use during the medical procedure. In some examples, the plan may be uploaded or otherwise communicated to a system including the external imaging device. The medical practitioner may then use the plan during the medical procedure, where the one or more selected imaging orientations may be displayed as a recommendation to the medical practitioner to provide guidance on which orientations of the external imaging device should be observed during the medical procedure. The recommended orientations may be displayed to the physician in any appropriate manner, including but not limited to a digital output, a visual output such as an orientation icon, a combination of the above, and / or any other appropriate type of indication.

[0063] Example: Determining Imaging Orientation

[0064] 7A to 7CAn example of a three-dimensional volume 600 including data from a computed tomography (CT) scan of a subject's torso is shown. The scan includes information such as the location of target tissue (e.g., a tumor, lesion, or other appropriate structure) and bony structures such as the subject's spine 606 and ribs 610. Fig. 7A Illustrated from a front perspective with a viewing angle of 0 degrees. Figure 7B and Figure 7C The same CT scan is shown at +25 degrees and -25 degrees respectively, which changes the relative positioning of different structures included in the field of view of the presented perspective. These different perspectives can therefore be used to determine what a two-dimensional X-ray image of a subject might look like before performing the procedure.

[0065] Fig. 8A and Figure 8B Depict using including from 7A to 7C The three-dimensional volume 600 of information from a CT scan is used to generate a projected two-dimensional image 612 for determining one or more imaging orientations for a medical procedure. The projected two-dimensional image can be generated using any of the methods described above. In the depicted example, the CT data includes a planned pose of a flexible, elongated device 604. The planned pose can be depicted by voxels within the three-dimensional volume 600 and pixels within the projected two-dimensional image 612, which have elevated intensities relative to surrounding background voxels and / or pixels. This can allow the pose of the flexible, elongated device 604 within the three-dimensional volume and the subsequently generated projected two-dimensional image 612 to be easily identified by an associated algorithm and / or user. The CT data can also include an identified site of the target tissue 602. In some examples, the site of the target tissue can be included in the CT data, and as shown in FIG. Figure 8B As depicted, the projected two-dimensional image 612 may be superimposed on the projected two-dimensional image 612 to enhance visualization of the target tissue relative to other features in the image. In some examples and as described above, the projected two-dimensional image 612 may also include an indication of the orientation of the external medical imaging device that may correspond to the presented image. This may include, for example Figure 8B An orientation icon 614 is shown, text, or any other suitable indicator of the imaging orientation associated with the image.

[0066] In addition to the above, Figure 8B A separation distance D is shown between the distal portion of the flexible elongated device 604 and the target tissue 602 within the projected two-dimensional image 612. The figure also shows a minimum distance B between the target tissue 602 and one or more bony structures, such as adjacent ribs 610, in the projected two-dimensional image 612. As detailed above, a user and / or an algorithm may use this type of information to help select an appropriate orientation for use during a medical procedure.

[0067] Although the above examples are generally described as generating projected two-dimensional images from CT data, as previously discussed, other external imaging systems configured to provide different types of external imaging data may also be used. This may include, for example, magnetic resonance imaging (MRI), fluoroscopy, thermal imaging, ultrasound, optical coherence tomography (OCT), thermal imaging, impedance imaging, laser imaging, nanotube X-ray imaging, and / or any other suitable type of imaging system. Therefore, it should be understood that any suitable type of external imaging data may be used to generate the desired projected two-dimensional image.

[0068] It should be understood that the above methods and other methods disclosed herein can be implemented in any suitable manner. For example, in some examples, the methods disclosed herein can be embodied as processor-executable instructions stored in a non-transitory computer-readable memory, which, when executed, causes the system to perform any of the methods disclosed herein. In addition, it should be understood that although a single processor is described, examples are envisioned in which the methods disclosed herein are implemented by any number of processors combined and / or working separately from each other.

[0069] The above method can be implemented by one or more controllers including at least one processor disclosed herein. The method can be embodied as computer executable instructions stored on a non-transitory computer readable memory associated with the at least one processor, so that when executed by the at least one processor, the system can perform any of the actions associated with the method disclosed herein. In addition, it should be understood that the disclosed order of steps is illustrative, and the disclosed steps can be performed in a different order, performed simultaneously, and / or can include one or more additional intermediate steps not shown, as the present disclosure is not limited thereto.

[0070] The above examples of the technology described herein can be implemented in any of a variety of ways. For example, the examples can be implemented using hardware, software, or a combination thereof. When implemented in software, the software code can be executed on any suitable processor or processor set, whether it is set in a single computing device or distributed in multiple computing devices. Such processors can be implemented as integrated circuits, with one or more processors in an integrated circuit component, including commercially available integrated circuit components known in the art by names such as CPU chips, GPU chips, microprocessors, microcontrollers, or coprocessors. Alternatively, the processor can be implemented in a custom circuit system (such as an ASIC) or a semi-custom circuit system generated by configuring a programmable logic device. As a further alternative, the processor can be part of a larger circuit or semiconductor device, whether commercially available, semi-custom, or custom. As a specific example, some commercially available microprocessors have multiple cores, so that one or a subset of those cores can constitute a processor. However, a circuit system in any suitable format can be used to implement the processor.

[0071] Furthermore, it should be understood that a computing device including one or more processors may be embodied in any of a variety of forms, such as a rack-mounted computer, a desktop computer, a laptop computer, or a tablet computer. Furthermore, the computing device may be embodied in a device not typically considered a computing device but having appropriate processing capabilities, including a personal digital assistant (PDA), a smart phone, a tablet computer, or any other suitable portable or fixed electronic device.

[0072] In addition, a computing device may have one or more input and output devices. Among other things, these devices may be used to present a user interface. Examples of output devices that may be used to provide a user interface include a display screen for visual presentation of output and a speaker or other sound generating device for auditory presentation of output. Examples of input devices that may be used for a user interface include a keyboard, a separate button, and a pointing device, such as a mouse, a touch pad, and a digitized tablet computer. As another example, a computing device may receive input information by voice recognition or in other audible formats.

[0073] Such computing devices may be interconnected by one or more networks of any suitable form, including a local area network or a wide area network, such as an enterprise network or the Internet. Such networks may be based on any suitable technology and may operate according to any suitable protocol, and may include wireless networks, wired networks, or fiber optic networks.

[0074] In addition, the various methods or processes outlined herein can be encoded as software that can be executed on one or more processors that adopt any of various operating systems or platforms. In addition, such software can be written using any of a variety of suitable programming languages ​​and / or programming or scripting tools.

[0075] In this regard, the examples described herein may be embodied as a computer-readable storage medium (or multiple computer-readable media) (e.g., computer memory, one or more floppy disks, compact disks (CDs), optical disks, digital video disks (DVDs), tapes, flash memory, RAM, ROM, EEPROM, circuit configurations in field programmable gate arrays or other semiconductor devices, or other tangible computer storage media) encoded with one or more programs that, when executed on one or more computers or other processors, can perform methods that implement the various examples discussed above. As is apparent from the above examples, a computer-readable storage medium can retain information for a sufficient period of time to provide computer-executable instructions in a non-transitory form. Such one or more computer-readable storage media may be transportable so that one or more programs stored thereon can be loaded onto one or more different computing devices or other processors to implement various aspects of the present disclosure, as discussed above. As used herein, the terms "computer-readable storage medium," "computer-readable memory," or other similar terms include only non-transitory computer-readable media that may be considered an article of manufacture (e.g., an article of manufacture) or a fluoroscope. Alternatively or additionally, the present disclosure may be embodied as a computer-readable medium other than a computer-readable storage medium, such as a propagated signal.

[0076] The term "program" or "software" as used herein refers in a general sense to any type of computer code or computer executable instruction set that can be used to program a computing device or other processor to implement various aspects of the present disclosure as discussed above. In addition, it should be understood that according to one aspect of this example, when executing the method of implementing the present disclosure, one or more computer programs do not need to reside on a single computing device or processor, but can be distributed in a modular manner between multiple different computers or processors to implement various aspects of the present disclosure.

[0077] Computer executable instructions can be in various forms, such as program modules, that are executed by one or more computers or other devices. Typically, program modules include routines, programs, objects, components, data structures, etc., which perform specific tasks or implement specific abstract data types. Typically, in various examples, the functionality of program modules can be combined or distributed as desired.

[0078] The examples described herein may be embodied as methods, examples of which have been provided. The actions performed as part of the method may be ordered in any suitable manner. Thus, examples may be constructed that perform actions in an order different from the illustrated order, which may include performing some actions simultaneously, even though shown as sequential actions in the illustrative examples.

[0079] Additionally, some actions are described as being taken by a “user.” It should be understood that a “user” is not necessarily a single individual, and in some examples, actions attributable to a “user” may be performed by a team of individuals and / or individuals in combination with computer-assisted tools or other mechanisms.

[0080] Although the present teaching is described in conjunction with various examples and examples, the present teaching is not intended to be limited to such one or more examples. On the contrary, it will be appreciated by those skilled in the art that the present teaching includes various alternatives, modifications and equivalent forms. Therefore, the above description and accompanying drawings are only intended to be examples.

Claims

1. A method comprising: Obtaining computed tomography data (CT data) of a subject, wherein the CT data includes a target tissue of the subject; obtaining a planned pose of a flexible elongated device within the anatomy of the subject; as well as Based on the CT data, the planned pose of the flexible elongated device and one or more parameters of an external imaging device, one or more projected two-dimensional images are formed.

2. The method of claim 1, wherein the external imaging device comprises an X-ray imaging device.

3. The method according to any of the preceding claims, wherein forming the one or more projected two-dimensional images comprises forming a plurality of projected two-dimensional images at a plurality of imaging orientations of the external imaging device.

4. The method of any of the preceding claims, further comprising determining one or more imaging orientations of the external imaging device for use during a medical procedure based at least in part on the one or more projected two-dimensional images. 5 . The method of claim 4 , wherein determining the one or more imaging orientations of the external imaging device comprises receiving a manual selection of one or more of the plurality of projected two-dimensional images.

6. The method of claim 4, wherein determining the one or more imaging orientations of the external imaging device comprises determining a projected two-dimensional image of the plurality of projected two-dimensional images having a maximum boundary area of ​​the flexible elongated device.

7. The method of claim 4, wherein determining the one or more imaging orientations of the external imaging device comprises determining a projected two-dimensional image among the plurality of projected two-dimensional images having a maximum cumulative curvature value along the planned posture of the flexible elongated device.

8. The method of claim 4, wherein determining one or more of the imaging orientations of the external imaging device comprises determining a separation distance between the target tissue in the plurality of projected two-dimensional images and a distal portion of the flexible, elongated device.

9. The method of claim 4, wherein determining the one or more imaging orientations of the external imaging device comprises determining a separation distance between the target tissue and one or more bone structures in the plurality of projected two-dimensional images.

10. The method of claim 9, further comprising determining locations of the one or more bone structures in the plurality of projected two-dimensional images based at least in part on a threshold intensity.

11. The method of claim 4, wherein determining the one or more imaging orientations of the external imaging device comprises determining visibility of the target tissue in the plurality of projected two-dimensional images.

12. The method of any one of claims 4 to 11, further comprising displaying to a user an indication of one or more medical activities associated with the determined one or more imaging orientations.

13. The method of any one of claims 4 to 12, further comprising storing the one or more determined imaging orientations on a non-transitory computer readable memory.

14. The method of any one of claims 4 to 13, wherein the one or more imaging orientations comprise one or more imaging orientations of a C-arm fluoroscope.

15. The method of any one of claims 4 to 14, further comprising outputting an indication of the one or more imaging orientations to a user.

16. The method of any of the preceding claims, wherein the planned pose is based on a planned path of the flexible medical device into the anatomy of the subject.

17. The method of any preceding claim, further comprising increasing the intensity of voxels in the CT data corresponding to the planned pose of the flexible medical device.

18. The method of any of the preceding claims, wherein the anatomical structure comprises a lung of the subject.

19. A non-transitory computer readable memory comprising instructions which when executed by one or more processors perform the method according to any one of the preceding claims.

20. A medical procedure planning device comprising: processor; as well as a non-transitory computer-readable memory storing computer-executable instructions that, when executed by the processor, cause the apparatus to: Obtaining computed tomography data (CT data) of a subject, wherein the CT data includes a target tissue of the subject; obtaining a planned pose of a flexible elongated device within the anatomy of the subject; as well as Based on the CT data, the planned pose of the flexible elongated device, and one or more parameters of an external imaging device, one or more imaging orientations of the external imaging device are determined for use during a medical procedure.

21. The apparatus of claim 20, wherein the external imaging device comprises an X-ray imaging device.

22. An apparatus according to any one of claims 20 to 21, wherein the computer executable instructions, when executed by the processor, cause the apparatus to form one or more projected two-dimensional images at the one or more imaging orientations of the external imaging device.

23. The apparatus of claim 22, wherein the one or more projected two-dimensional images comprises a plurality of projected two-dimensional images at a plurality of imaging orientations of the external imaging device.

24. The apparatus of claim 23, wherein the plurality of imaging orientations of the external imaging device are manually selected.

25. The apparatus of claim 23, wherein the computer executable instructions, when executed by the processor, cause the apparatus to determine a projected two-dimensional image of the plurality of projected two-dimensional images having a largest border area of ​​the flexible elongated device.

26. The apparatus of claim 23, wherein the computer executable instructions, when executed by the processor, cause the apparatus to determine a projected two-dimensional image of the plurality of projected two-dimensional images having a maximum cumulative curvature value along the planned pose of the flexible elongated device.

27. The apparatus of claim 23, wherein the computer executable instructions, when executed by the processor, cause the apparatus to determine a separation distance between the target tissue and a distal portion of the flexible elongate device in the plurality of projected two-dimensional images.

28. The apparatus of claim 23, wherein the computer executable instructions, when executed by the processor, cause the apparatus to determine a separation distance between the target tissue and one or more bone structures in the plurality of projected two-dimensional images.

29. The apparatus of claim 28, wherein the computer executable instructions, when executed by the processor, cause the apparatus to determine locations of the one or more bone structures in the plurality of projected two-dimensional images based at least in part on a threshold intensity.

30. The apparatus of claim 23, wherein the computer executable instructions, when executed by the processor, cause the apparatus to determine visibility of the target tissue in the plurality of projected two-dimensional images.

31. An apparatus according to any one of claims 20 to 30, wherein the computer executable instructions, when executed by the processor, cause the apparatus to display to a user an indication of one or more medical activities associated with the determined one or more imaging orientations.

32. The apparatus of any one of claims 20 to 31, wherein the computer executable instructions, when executed by the processor, cause the apparatus to store the one or more determined imaging orientations on a non-transitory computer readable memory.

33. The apparatus of any one of claims 20 to 32, wherein the one or more imaging orientations comprise one or more imaging orientations of a C-arm fluoroscope.

34. An apparatus according to any one of claims 20 to 33, wherein the computer executable instructions, when executed by the processor, cause the apparatus to output an indication of the one or more imaging orientations to a user.

35. The apparatus of any one of claims 20 to 34, wherein the planned pose is based on a planned path of the flexible medical device into the anatomical structure of the subject.

36. The apparatus of claim 35, wherein the computer executable instructions, when executed by the processor, cause the apparatus to increase the intensity of voxels in the CT data corresponding to the planned path of the flexible medical device.

37. The device of any one of claims 20 to 36, wherein the anatomical structure comprises a lung of the subject.

Images