Target movement modeling using electromagnetic navigation sensors

Abstract

Systems and methods for target movement modeling use a sequence of position data from a first electromagnetic (EM) sensor disposed at a distal portion of a catheter disposed in the lung and from at least one second EM sensor disposed at the patient's chest in order to update a target tissue position. The methods involve generating a pulmonary breathing model from breathing phases based on the position data from the first EM sensor and the second EM sensor. The methods also involve receiving current position data from the at least one second EM sensor, and estimating a current breathing phase based on the breathing model and the current position data. The methods also involve predicting a displacement of the target based on the breathing model and the current breathing phase, and updating body coordinates in the vicinity of the target based on the displacement of the target.

Description

Cross-reference to related applications

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 545,207, filed October 23, 2023, and U.S. Patent Application Serial No. 18 / 895,020, filed September 24, 2024, the entire contents of each of these U.S. patent applications are incorporated herein by reference. Technical Field

[0002] The technology disclosed herein generally relates to modeling the movement of target tissue based on location information from one or more electromagnetic (EM) sensors in order to correct local patient body coordinates. Background Technology

[0003] When performing medical procedures, clinicians frequently rely on patient data, including X-ray data, computed tomography (CT) scan data, magnetic resonance imaging (MRI) data, or other imaging data that allows clinicians to view the patient's internal anatomy. Imaging data is also used to identify targets of interest and develop strategies for approaching those targets for surgical treatment. Furthermore, imaging data has been used to create three-dimensional (3D) models of the patient's body to guide medical devices to navigate to targets of interest within the patient's body.

[0004] Since it is crucial to process a target at its exact location from the planned orientation, even a small difference between the actual and estimated location of a medical device can cause undesirable consequences during medical procedures. Therefore, it is highly desirable to estimate the actual location of medical devices with a sufficiently high level of accuracy during medical procedures.

[0005] Furthermore, as the medical device approaches the target according to the 3D model, even though the medical device is stably positioned within the patient's body relative to the internal organs surrounding the target, the patient's breathing and heartbeat make the medical device appear to move within the 3D model. Therefore, stable respiratory movement is beneficial for accurately displaying the position of the medical device during medical procedures. Summary of the Invention

[0006] The technology disclosed herein generally relates to modeling the movement of target tissue based on location information from one or more electromagnetic (EM) sensors in order to correct local patient body coordinates.

[0007] In one aspect, this disclosure provides a method for updating the position of a target based on the target's compatible movement. The method includes determining the movement of a catheter disposed in the lungs during at least one respiratory cycle of a patient, and generating a movement model of the target based on the movement of the catheter. The method also includes determining the movement of at least one chest tube (PST) during at least one respiratory cycle of the patient, and generating a movement model of the patient's chest based on the movement of the at least one PST. The method further includes receiving a real-time PST signal from the at least one PST, and estimating the respiratory phase based on the chest movement model and the real-time PST signal. The method also includes estimating a movement of the target compatible with the target's movement model based on the respiratory phase, thereby generating a compatible movement of the target, and updating the target's position based on the compatible movement of the target.

[0008] In various aspects, implementations of a method for updating the position of a target based on the compatibility movement of the target may include one or more of the following features: The position of the target can be updated in the patient's body coordinates. The method may include updating the position of the catheter based on the updated position of the target. The method may include updating the position of the target according to the respiratory phase. The method may include filtering the real-time PST signal to remove frequencies outside the normal respiratory rate range.

[0009] Determining catheter movement may include receiving position data from at least one EM sensor located at the distal portion of the catheter during at least one respiratory cycle of the patient, and filtering the position data to remove position values ​​outside a predetermined range. The method may include determining that the amplitude of the catheter position data is greater than a threshold during a respiratory cycle, and not updating the target position in response to determining that the amplitude of the catheter position data is greater than the threshold during a respiratory cycle.

[0010] In another aspect, this disclosure provides a method for updating body coordinates near a target based on the target's displacement. The method includes generating a lung breathing model based on position data from a first electromagnetic (EM) sensor positioned at the distal portion of a catheter disposed in a patient's lung and from at least one second EM sensor positioned on the patient's chest, according to the respiratory stage. The method also includes receiving current position data from the at least one second EM sensor and estimating the current respiratory stage based on the breathing model and the current position data. Furthermore, the method includes predicting the average displacement of the target relative to the target based on the breathing model and the current respiratory stage, and updating the body coordinates near the target based on the target's displacement.

[0011] In various aspects, implementations of a method for updating body coordinates near a target based on target displacement may include one or more of the following features: At least one second EM sensor may be at least one PST. Generating a lung breathing model may include generating a chest movement model based on position data from a first EM sensor according to the breathing stage, generating a target movement model based on position data from at least one second EM sensor according to the breathing stage, and combining the chest movement model and the target movement model to obtain a lung breathing model. Receiving current position data, estimating the current breathing stage, predicting the target displacement, and updating body coordinates may be performed during navigation procedures, biopsy procedures, or ablation procedures.

[0012] The method may include displaying a message to the user indicating that the catheter should be navigated to the vicinity of a target. The method may also include displaying a message to the user indicating that the catheter should not be moved. The method may further include simultaneously recording position data from a first EM sensor and from at least one second EM sensor during at least one respiratory cycle of the patient.

[0013] In another aspect, this disclosure provides a system for updating body coordinates near a target tissue based on displacement of that target tissue. The system includes: a catheter configured to be placed near the target tissue in a patient's lung; a first electromagnetic (EM) sensor disposed at a distal portion of the catheter; and at least one second EM sensor disposed on the patient's chest. The system also includes a processor and a memory storing instructions that, when executed by the processor, cause the system to receive first position data from the first EM sensor, receive second position data from the at least one second EM sensor, and generate a lung breathing model based on the first and second position data according to respiratory stages.

[0014] When executed by the processor, these instructions also cause the system to receive current position data from at least one second EM sensor and estimate the current respiratory stage based on the respiratory model and the current position data. When executed by the processor, these instructions also cause the system to predict the displacement of the target tissue based on the respiratory model and the current respiratory stage, and update the body coordinates near the target tissue based on the displacement of the target tissue.

[0015] In various aspects, implementations of the system may include one or more of the following features. These instructions, when executed by a processor, enable the system to generate a lung tissue movement model based on position data from a first EM sensor according to the respiratory phase, to generate a chest movement model based on position data from at least one second EM sensor according to the respiratory phase, and to generate a lung breathing model based on the target tissue movement model and the chest movement model.

[0016] When executed by the processor, these instructions enable the system to receive current location data, estimate the current respiratory stage, predict the displacement of the target tissue, and update body coordinates during navigation, biopsy, or ablation procedures. The system may include a display, and when executed by the processor, these instructions may cause the display to show the user a message directing the catheter to the vicinity of the target tissue.

[0017] When executed by the processor, these instructions enable the system to simultaneously record first and second position data during at least one respiratory cycle of the patient. When executed by the processor, these instructions enable the system to: register the coordinates of at least one second EM sensor with the coordinates of the patient's body, thereby generating sensor-body registration; determine that lung tissue movement is less than a threshold; and correct the sensor-body registration in response to determining that lung tissue movement is less than the threshold.

[0018] Details of one or more aspects of this disclosure are set forth in the accompanying drawings and the following description. Other features, objects, and advantages of the technology described in this disclosure will become clear from the specification, drawings, and claims. Attached Figure Description

[0019] Figure 1 It is a block diagram showing a system for acquiring and processing 3D CBCT scans of patients and positioning plates;

[0020] Figure 2 It is a demonstration Figure 1 The circuit block diagram of the system's workstation;

[0021] Figure 3 This is a flowchart illustrating an example of a method for correcting the position of a catheter and / or target tissue near the catheter;

[0022] Figure 4 This is a flowchart illustrating an example of a method for generating a breathing model; and

[0023] Figure 5 This is a flowchart illustrating another example of a method for correcting the position of a catheter and / or target tissue near the catheter. Detailed Implementation

[0024] During an electromagnetic guided bronchoscopy (ENB) procedure, the lung tissue moves continuously due to the patient's breathing and heartbeat. When the lungs inhale, the diaphragm contracts and pulls downwards towards the abdominal cavity. Simultaneously, the intercostal muscles (muscles between the ribs) contract and pull upwards along the rib cage. This increases the size of the thoracic cavity and decreases the pressure within it. As a result, air rushes in and fills the lungs. When the lungs exhale, the diaphragm relaxes, and the volume of the thoracic cavity decreases, while the pressure within it increases. Therefore, the lungs contract, and air is forced out.

[0025] Therefore, the focus or target in the lungs moves periodically. On average, the movement along the main direction is about 2.5 mm, but can reach up to 1.5 cm or even more. The magnitude and direction of movement vary depending on the location of the target in the lungs (which lobe it is located in, its proximity to rigid structures, etc.).

[0026] Medtronic's lighting navigation system continuously tracks navigation sensors (e.g., Figure 1 The location of sensor 104a) in the airway of the lungs is shown in the diagram. First, the position of the navigation sensor is solved in antenna coordinates. Next, as... Figure 1 As shown, the navigation sensor position is transformed into estimated body coordinates based on continuous tracking of the patient sensor triplet (PST) 118. The PST 118 senses general chest movement and can sense chest respiratory movement; however, diaphragmatic movement is not sensed by the PST 118. Therefore, most respiratory movements are not indicated. Furthermore, lung tissue movement due to heartbeat may not be sensed. Therefore, the navigation duct position within the airway tree is not accurate. For example, when the navigation duct moves continuously due to respiratory and / or cardiac activity, the target may appear static when in reality both the target and the navigation duct are moving.

[0027] As another example, in a target overlay, the estimated target location is projected onto a real-time fluorescence fluoroscopic image; however, uncompensated body movement causes inaccuracies in the target overlay. The overlay can remain relatively static as the anatomical structures and target beneath it move continuously.

[0028] According to various aspects of this disclosure, the navigation catheter is used to record and model the movement of a target during the respiratory cycle. The PST 118 is used to model chest movement during the respiratory cycle.

[0029] Respiratory compensation can be accomplished by estimating the respiratory phase using a real-time PST signal and estimating compatible target movement within the estimated respiratory phase. Respiration can be characterized as a continuous periodic movement measured by PST 118. The inspiratory and expiratory phases are two extreme phases that can be sampled from the real-time PST signal. Alternatively or additionally, a system or method may involve sampling the real-time PST signal at a larger granularity. For example, if the entire respiratory cycle is 6 seconds long, the phase value can be any integer between 0 and 6. Typically, the phase value can be any integer between 0 and some non-negative, non-zero integer. This non-negative, non-zero integer can be increased to a desired value to achieve the desired resolution or accuracy of the respiratory phase. Next, a local correction can be created in body coordinates and continuously updated based on the respiratory phase. The catheter position and / or target position can then be updated based on the local correction.

[0030] Figure 1 This is a stereoscopic view of an example of a system 100 for facilitating the navigation of a medical tool (e.g., a catheter) to a target via an airway through the lungs. System 100 may be further configured to construct radiographic-based volumetric data of a target region based on intraoperative 2D radiographic images (e.g., intraoperative fluoroscopic images and / or CBCT images) to confirm navigation of the sEWC to a desired location near the target region, wherein the tool may be positioned to pass through and extend beyond the sEWC. In various aspects, the imaging system 124 of system 100 may include one or more of a C-arm fluoroscopy system, a 3D cone-beam computed tomography (CBCT) imaging system, and a 3D fluoroscopic imaging system.

[0031] System 100 can be further configured to facilitate the approach of a medical tool or instrument to a target area and determine the position of the medical tool relative to the target by using electromagnetic navigation (EMN) of the sEWC. One such EMN system is the ILLUMISITE system currently sold by Medtronic, but other systems for intracavitary navigation are also considered to be within the scope of this disclosure.

[0032] One aspect of system 100 is a software component for viewing computed tomography (CT) image scan data acquired separately from system 100. Viewing the CT image data allows a user to identify one or more targets, plan a path to the identified targets (planning phase), navigate the sEWC 102 to the targets using a user interface running on computer system 122 (navigation phase), and confirm the placement of the distal portion of the sEWC 102 near the target using one or more electromagnetic (EM) sensors 104b, 126 positioned at or near a predetermined location in or on the distal portion of the sEWC 102. While this disclosure relates to an sEWC 102 having one or more EM sensors 104b, 126, this disclosure contemplates the use of any suitable endovascular device comprising one or more positioning sensors (e.g., any or both of the EM sensors 104b, 126) located at the distal tip or end portion of the endovascular device, and capable of navigation to a target region of the lungs via airways. For example, the sEWC 102 can be replaced by an EWC or other suitable catheters incorporating positioning sensors and capable of navigation to a target area of ​​the lungs via the airways. The positioning sensor can be any suitable sensor that provides x, y, z coordinates.

[0033] The target can be a tissue of interest identified by reviewing CT image data during the planning phase. After navigating the sEWC102 to the vicinity of the target, a medical tool (such as a biopsy tool, access tool, or treatment tool, e.g., a flexible microwave ablation catheter) is inserted into the sEWC102 and fixed in place relative to it, such that the distal portion of the medical tool extends beyond the desired distal distance 107 of the sEWC102, and the sEWC102 is further navigated using EM navigation to obtain tissue samples, enable access to the target site, or treat the target using the medical tool.

[0034] like Figure 1As shown, sEWC 102 is part of the catheter guidance assembly 110. In practice, sEWC 102 is inserted into the bronchoscope 108 to access the lumen network of the patient P. Specifically, sEWC 102 of the catheter guidance assembly 110 can be inserted into the working channel of the bronchoscope 108 for navigation through the patient's lumen network. A bronchoscope adapter 109 is coupled to the proximal portion of the bronchoscope. The bronchoscope adapter 109 may be an EDGE™ bronchoscope adapter, currently marketed and sold by Medtronic. The bronchoscope adapter 109 is configured to allow sEWC 102 to move through the working channel of the bronchoscope 108 (this may be referred to as the unlocked state of the bronchoscope adapter 109) or to prevent sEWC 102 from moving through the working channel of the bronchoscope (this may be referred to as the unlocked state of the bronchoscope adapter 109).

[0035] The aspects of this disclosure can be applied to a variety of procedures, including biopsy, ablation, or marker placement procedures. For example, these procedures may involve one or more of a positionable guide 101a, a microwave ablation tool 101b, a biopsy needle 101c, or forceps 101d. The positionable guide (LG) 101a may be a catheter and may include a sensor 104a similar to sensor 104b, which is inserted into and locked in place in the sEWC 102 such that sensor 104a extends beyond a predetermined distance of the distal portion of the sEWC 102. Tools 101a-101d of the same length include retaining members 103a-d such that when the retaining members 103a-103d of tools 101a-101d engage (e.g., bite) with the proximal portion of the handle 106 of the catheter guide assembly 110, LG 101a extends beyond a predetermined distance 107 of the distal tip or end portion of the sEWC 102. The predetermined distance 107 may be based on the length of sEWC 102 and the length between the end portions of the handles 105a-d or the fixing members 103a-103d and the distal portions of LG 101a or other medical tools 101b-101d. In various aspects, the handles 105a-105d may include control objects, such as buttons or levers, for controlling the operation of the medical tools 101a-101d.

[0036] In some respects, the position of the fixation members 105a-105d along the length of the medical instruments 101a-101d can be adjustable, allowing the user to adjust the distance by which the distal portion of LG 101a or the medical instruments 101b-101d extends beyond the distal portion of sEWC 102. The position and orientation of the LG sensor 104a relative to a reference coordinate system within the electromagnetic field can be obtained using an application executed by computer system 122. In some respects, sEWC 102 can act as LG 101a, in which case LG 101a may not be used. In other respects, sEWC 102 and LG 101a can be used together. For example, data from sensors 104a and 104b can be fused together. The catheter guidance assembly 110 is currently marketed and sold by Medtronic Corporation under the trade names SUPERDIMENSION® Program Kit or EDGE™ Program Kit and is considered to be usable with this disclosure.

[0037] System 100 typically includes: an operating table 112 configured to support patient P; a bronchoscope 108 configured for insertion into patient P's airway through the patient P's mouth; a monitoring device 114 coupled to the bronchoscope 108 (e.g., a video display for displaying video images received from a video imaging system of the bronchoscope 108); and a tracking system 115 including a tracking module 116, a patient sensor triplet (PST) 118, and a positioning or transmitter plate 120. The positioning plate 120 includes one or more EM transmitters for generating an EM field.

[0038] The positioning plate 120 may also include reference points that may be embedded or otherwise incorporated into the positioning plate 120 and are designed and / or arranged to appear in radiographic images for the purpose of creating 3D reconstructions from the radiographic images. Because reference points may be densely packed in radiographs, they can produce artifacts on radiographic images (e.g., intraoperative 3D CBCT images). System 100 further includes a computer system 122 on which software and / or hardware are used to facilitate target identification, plan paths to the target, navigate medical tools to the target, and / or confirm and / or determine the placement of the sEWC 102 or appropriate tools passing through it relative to the target.

[0039] As described above, an optional imaging system 124 capable of acquiring 3D CBCT images or fluorescence fluoroscopy images of patient P is also included in system 100. Images, image sequences, or videos captured by imaging system 124 can be stored within imaging system 124 or transmitted to computer system 122 for storage, processing, and display. Additionally, imaging system 124 can be moved relative to patient P, allowing images to be acquired from different angles or viewpoints relative to patient P to create a series of 3D CBCT images.

[0040] The orientation of the imaging system 124 relative to the patient P, and its orientation at the time of image capture, can be estimated via markers combined with a transmitter pad 120 in the operating table 112 or a pad (not shown) placed between the patient and the operating table 112. The markers are positioned below the patient P, between the patient P and the operating table 112, and between the patient P and the radiation source or sensing unit of the imaging system 124. The markers may have symmetrical or asymmetrical spacing, repeating patterns, or no pattern at all. The imaging system 124 may include a single imaging system or more than one imaging system. When using a CBCT system, the captured images can be used to confirm the location of one of the sEWC 102 and / or medical instruments 101a-101d within the patient, update the CT-based 3D model, or replace the preoperative 3D model with intraoperative modeling of the patient's airway and the location of the sEWC 102 within the patient.

[0041] Computer system 122 can be any suitable computer system including a processor and storage media, such that the processor is capable of executing instructions stored on the storage media. Computer system 122 may further include a database configured to store patient data, CT datasets including CT images, 3D CBCT images and datasets, 3D fluoroscopy datasets including 3D fluoroscopy images and videos, 3D reconstructions, navigation planning, and any other such data. Although not explicitly shown, computer system 122 may include input terminals, or may be otherwise configured to receive CT datasets, CBCT or fluoroscopy images or videos, and other suitable imaging data. Additionally, computer system 122 includes a display configured to display a graphical user interface. Computer system 122 may be connected to one or more networks through which computer system 122 can access one or more databases.

[0042] Regarding the navigation phase, a six-degree-of-freedom electromagnetic positioning or tracking system 115 or other suitable system (e.g., fiber-optic Bragg flexible sensor) for determining the position and orientation of the distal portion of sEWC 102 is used to perform registration of preoperative images (e.g., CT image datasets and 3D models derived therefrom) and navigation paths with the patient while the patient is on the operating table 112.

[0043] In the EMN-type system, the tracking system 115 may include a tracking module 116, a PST 118, and a positioning plate 120 (including markers). The tracking system 115 is configured for use with a positionable guide (particularly an LG sensor). As described above, a medical instrument (e.g., a positionable guide 101a with an LG sensor 104a) is configured to be inserted into the airway of patient P (with or without a bronchoscope 108) via a sEWC 102 and can be selectively locked relative to each other via a locking mechanism (e.g., a bronchoscope adapter 109). The transmitter pad 120 is positioned below patient P. The transmitter pad 120 generates an electromagnetic field around at least a portion of patient P, within which the positions of the LG sensor 104a, sEWC sensor 104b, and PST 118 can be determined using the tracking module 116. An additional electromagnetic sensor 126 may also be incorporated into the end of the sEWC 102. The additional electromagnetic sensor 126 can be a five-degree-of-freedom sensor or a six-degree-of-freedom sensor. One or more of the reference sensors of PST 118 are attached to the chest of the patient P.

[0044] Registration refers to the method of associating the coordinate system of a preoperative image (particularly a 3D model derived therefrom) with, for example, the airway of patient P as observed via bronchoscopy 108, and allows for navigation with an accurate understanding of the location of the LG sensor within the patient's body and an accurate depiction of that location in the 3D model. Registration can be performed by moving the LG sensor through patient P's airway. More specifically, as the locatable guide moves through the airway, data relating to the location of the LG sensor is recorded using transmitter pad 120, PST 118, and tracking system 115. The shape generated from this location data is compared with the internal geometry of the channel in the 3D model generated during the planning phase, and the positional correlation between the shape and the 3D model is determined based on this comparison, for example using software on computer system 122. The software aligns or registers the image representing the location of the LG sensor with the 3D model and / or a two-dimensional image generated from the three-dimensional model, based on the recorded location data and the assumption that the LG remains located in non-tissue space within patient P's airway. Alternatively, manual registration techniques can be utilized by navigating the bronchoscope 108 with the LG sensor to a pre-designated location in the lungs of patient P and manually correlating the images from the bronchoscope 108 with model data from the 3D model.

[0045] Although an EMN system using an EM sensor is described herein, this disclosure is not limited thereto and can be used in conjunction with flexible sensors, shape sensors (such as fiber Bragg grating sensors), ultrasonic sensors, or any other suitable sensors that do not emit harmful radiation. Furthermore, the methods described herein can be used in conjunction with robotic systems to enable robotic actuators to drive the sEWC 102 or bronchoscope 108 toward a target.

[0046] At any point during the navigation process, tools such as the positionable guide 101a, treatment tools (e.g., microwave ablation tool 101b or forceps 101d), and biopsy tools (e.g., biopsy needle 101c) can be inserted into and fixed in place relative to the sEWC 102 to place one of the tools 101a-101d near the target using positional information from the sEWC 102. The position of the distal tip or distal portion of any of the tools 101a-101d can be calculated using positional information from sensors 104b and / or 126 of the sEWC 102.

[0047] To ensure the accuracy of position calculations, tools 101a-101d are each designed to extend a predetermined distance from the distal end of sEWC 102, and at least the distal portions of tools 101a-101d extending from sEWC 102 are designed to be rigid or substantially rigid. This predetermined distance can vary depending on one or more of the design of tools 101a-101d, the rigidity of tools 101a-101d, or how each tool 101a-101d interacts with different types of tissue. Tools 101a-101d can be designed or characterized to set the predetermined distance to ensure that deflection is managed (e.g., minimized), such that the virtual tools and environment displayed to clinicians are an accurate representation of the actual clinical tools and environment.

[0048] The position of the distal portion of any of the calculation tools 101a-101d may include position information projected distally from sensors 104b and / or 126 based on tool information. Tool information may include one or more of the following: tool shape, tool type, tool hardness, type or characteristic of the tissue to be treated, or tool size.

[0049] Regarding the planning phase, computer system 122, or a separate computer system (not shown), utilizes pre-acquired CT image data to generate and view a 3D model or rendering of the patient P's airway, enabling target identification (automatic, semi-automatic, or manual) and allowing the determination of pathways through the patient P's airway to the tissue located at and around the target. More specifically, CT images acquired via CT scans are processed and assembled into a 3D CT volume, which is then used to generate a 3D model of the patient P's airway. This 3D model can be displayed on a monitor associated with computer system 122, or in any other suitable manner. Using computer system 122, various views of the 3D model or enhanced 2D images generated from the 3D model are presented. The enhanced 2D images may have some 3D capabilities because they are generated from 3D data. The 3D model can be manipulated to facilitate target identification on the 3D model or 2D images, and appropriate pathways can be selected for the patient P's airway to reach the tissue located at the target. Once a selection is made, the route plan, 3D model, and images derived from it can be saved and exported to the navigation system for use during (multiple) navigation phases. The ILLUMISITE software suite currently sold by Medtronic includes such planning software.

[0050] Now for reference Figure 2 The image is Figure 1 A schematic diagram of a computer system 122 configured to implement including Figure 2 The method disclosed herein is a method of the present invention. Computer system 122 may include a workstation. In some aspects, computer system 122 may be coupled directly or indirectly to an imaging system, for example, via wireless communication. Computer system 122 may include memory 202, processor 204, display 206, and input device 210. Processor 204 may include one or more hardware processors. Computer system 122 may optionally include output module 212 and network interface 208. Memory 202 may store application program 218 and sensor data 214, including data from one or more EM sensors located at the distal portion of the duct and the EM sensor of PST 118. Application program 218 may include functions executable by processor 204 for performing operations including... Figure 3-5 The instructions of this disclosure are for the method of the method.

[0051] Application 218 may further include user interface 216. Image data may include preoperative CT image data, intraoperative 3D fluorescence fluoroscopy image data, preoperative or intraoperative 3D CBCT image data and / or 3D reconstruction data. Processor 204 may be coupled to memory 202, display 206, input device 210, output module 212, network interface 208 and imaging system. Computer system 122 may be a fixed computer system such as a personal computer or a portable computer system such as a tablet computer. Computer system 122 may embed multiple computers.

[0052] Memory 202 may include any non-transitory computer-readable storage medium for storing data and / or software, including instructions executable by processor 204, that control the operation of computer system 122, process data from one or more EM sensors disposed in or on the sEWC (e.g., at the distal portion of the sEWC) to track the position of the sEWC and calculate or project the position of the distal portion of a medical instrument located at a fixed position within the sEWC, and in some aspects, may also control the operation of an imaging system. The imaging system may be used to capture a series of preoperative CT images of a part of the patient's body (e.g., the lungs) as a part of the patient's body moves (e.g., as the lungs move during respiratory circulation). Optionally, the imaging system may include a 3D CBCT imaging system or a 3D fluorescence fluoroscopy imaging system that captures a series of images, generates a 3D reconstruction based on the series of images, and / or captures real-time 2D views to confirm the placement of the sEWC and / or medical instrument. In one aspect, memory 202 may include one or more storage devices, such as solid-state storage devices, e.g., flash memory chips. Alternatively, or in addition to one or more solid-state storage devices, memory 202 may include one or more mass storage devices connected to processor 204 via a mass storage controller (not shown) and a communication bus (not shown).

[0053] Although the description of computer-readable media contained herein refers to solid-state storage devices, those skilled in the art will understand that computer-readable storage media can be any available medium accessible to processor 204. That is, computer-readable storage media can include non-transitory, volatile and non-volatile, removable and non-removable media implemented using any method or technique for storing information such as computer-readable instructions, data structures, program modules, or other data. For example, computer-readable storage media can include RAM, ROM, EPROM, EEPROM, flash memory or other solid-state memory technologies, CD-ROM, DVD, Blu-ray or other optical storage devices, magnetic cassettes, magnetic tapes, disk storage devices or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible by computer system 122.

[0054] When executed by processor 204, application 218 can cause display 206 to present user interface 216. User interface 216 can be configured to present a single screen to the user, including a 3D view of a three-dimensional (3D) model of the target from the perspective of the tip of the medical tool, a real-time two-dimensional (2D) view of the medical tool, and a target marker corresponding to the 3D model of the target overlaid on the real-time 2D view. User interface 216 can be further configured to display the target marker in different colors depending on whether the tip of the medical tool is aligned with the target in three dimensions.

[0055] Network interface 208 can be configured to connect to a network, such as a local area network (LAN), wide area network (WAN), wireless mobile network, Bluetooth network, and / or the Internet, consisting of wired and / or wireless networks. Network interface 208 can be used to establish a connection between computer system 122 and imaging system 515. Network interface 208 can also be used to receive sensor data 214. Input device 210 can be any device that a user can use to interact with computer system 122, such as a mouse, keyboard, foot pedal, touchscreen, and / or voice interface. Output module 212 can include any connection port or bus, such as a parallel port, serial port, universal serial bus (USB), or any other similar connection port known to those skilled in the art. Based on the foregoing and with reference to the various accompanying drawings, those skilled in the art will understand that certain modifications can be made to this disclosure without departing from the scope of this disclosure.

[0056] In all aspects, target organization movement modeling can be performed and used according to Figure 3 The illustrated method 300, in whole or in part, updates body coordinates near the target tissue. Method 300 or other similar methods disclosed herein can be divided into a setup phase and a usage phase. During the setup phase, the catheter is navigated to the vicinity of the target, catheter sensor and / or PST data is acquired and processed, and a respiratory model is generated based on the processed catheter sensor and / or PST data. During the usage phase, real-time PST data is acquired and used to predict the current respiratory cycle phase, target displacement is predicted based on the current respiratory cycle phase, and local body coordinates near the target are updated based on the predicted target displacement. This effectively compensates for respiration and / or heartbeat. Respiration causes continuous periodic movement, thus forming a respiratory cycle. A respiratory cycle can be decomposed into an inspiratory phase and an expiratory phase. In various aspects, PST signals can be sampled at a larger granularity to obtain a larger granularity of respiratory cycle phases. For example, if the respiratory cycle period is 6 seconds, the respiratory cycle phase can include integer phase values ​​ranging from 0 to 6.

[0057] The aspects of this disclosure can be combined with heartbeat information. Target movement caused by heartbeat is influenced by the proximity of the target to the heart. Otherwise, target movement caused by respiration can be the dominant movement, and target movement caused by heartbeat can be considered noise or ignored. In all aspects, only the PST positioning signal can be used to deduce the respiratory phase. Therefore, after recording the PST positioning signal, the PST positioning signal can be "cleaned up" by filtering out frequencies that are not close to the normal respiratory rate.

[0058] exist Figure 3 Prior to block 302, a clinician uses a catheter with an EM sensor at or near the tip to navigate to a target vicinity. In various aspects, method 300 may include displaying a message to a user (e.g., a clinician) indicating that the catheter is being navigated to a target vicinity using EM navigation. Method 300 may include displaying a message to the user indicating that the catheter is not being moved, allowing it to move only due to movement of lung tissue. Method 300 may include, for example, presenting an estimated movement or amplitude of breathing or a respiratory cycle via a display, allowing the user to know how important breathing is in the vicinity of the target. At block 302, first position data is received from a first EM sensor located at the distal portion of the catheter positioned near the target lung tissue in the patient. The first position data may be recorded for at least one complete respiratory cycle.

[0059] In various aspects, during the setup phase, breathing correction can be performed either consistently when the catheter is near the target or only when the catheter movement exceeds a threshold. Therefore, as an option, at box 303, method 300 determines whether first location data indicates catheter movement greater than a threshold. The threshold can be determined based on maximum catheter movement determined from medical data from one or more patients. If method 300 determines the catheter movement is greater than the threshold, method 300 terminates at box 318 until the next location data acquisition cycle begins. If method 300 determines the catheter movement is not greater than the threshold, method 300 proceeds to setup box 304. Alternatively or additionally, antenna-to-body registration can be performed only if significant lung tissue movement is present during the setup phase. In various aspects, an assessment of lung tissue movement can be performed between boxes 304 and 306 to determine whether antenna-to-body registration should be performed.

[0060] At box 304, second position data is received from a second EM sensor (e.g., PST 118) positioned on the patient's chest. The second position data can be recorded for at least one complete respiratory cycle. Furthermore, the second position data can be recorded simultaneously with the first position data. To ensure that the catheter is moved only by lung tissue, method 300 may include displaying a message warning the clinician not to move the catheter during the recording of both the first and second position data.

[0061] Secondary position data (e.g., PST position data) can be used solely to deduce the respiratory phase. Therefore, after recording secondary position data, it can be "cleaned" by filtering out frequencies that are not close to the normal respiratory rate range. The normal respiratory rate range can be predetermined based on an individual's age. For example, the normal respiratory rate range can be defined as follows: newborns (0-1 month): 30-60 breaths / minute (bpm); infants (1-12 months): 30-40 bpm; toddlers (1-2 years): 24-40 bpm; preschool children (3-5 years): 22-34 bpm; school-aged children (6-12 years): 18-30 bpm; adolescents (13-18 years): 12-20 bpm; adults (18 years and older): 12-20 bpm; and the elderly: 12-22 bpm.

[0062] Filtering can be performed by any filter suitable for filtering out frequencies other than the normal respiratory rate. The filter can be a digital filter configured as a low-pass, high-pass, or band-pass filter. The digital filter can be a finite impulse response (FIR) filter or an infinite impulse response (IIR) filter. Specifically, the digital filter can be a Butterworth filter, a Chebyshev filter, an elliptic (Caull) filter, a Bessel filter, a Parks-McClellan filter, or a window filter. The normal respiratory rate can be determined patient-by-patient based on patient data related to respiratory rate (e.g., age, anatomy, and medical history).

[0063] While target area movement can also be influenced by heartbeat, the method of this disclosure derives the respiratory phase from a PST designed to sense target area movement caused by respiration. In other words, if target area movement is due to heartbeat, the method of this disclosure may not adequately compensate for the target area movement. Therefore, method 300 can separate heartbeat-related movement from respiratory-related movement by: analyzing second position data based on frequency, separating second position data based on frequency, and generating a separate target movement model based on the separated second position data. Separating second position data based on frequency may include identifying a first frequency range associated with respiratory-related movement and a second frequency range associated with heartbeat-related movement, and determining a first component of the second position data within the first frequency range and a second component of the second position data within the second frequency range.

[0064] The method disclosed herein can generate respiratory-related movement models and heart-related movement models, which can be applied independently. As described herein, the respiratory-related movement model can be based on respiratory phases derived from the PST. For the heart-related movement model, the current heartbeat phase can be estimated using a heartbeat sensor, or it can be derived from catheter localization by identifying the periodic components of catheter movement within the heartbeat frequency range.

[0065] At box 306, a lung breathing model is generated based on the first and second position data according to the breathing stage. The breathing model can be a dynamic three-dimensional (3D) model of the entire respiratory cycle. The breathing model can also be called a four-dimensional (4D) model because time is the fourth dimension of a 4D model. The breathing model can be generated based on a combination of a chest movement model according to the breathing stage and a target movement model according to the current breathing stage.

[0066] The target movement model can be generated based on 4D positioning signals from sensors at the tip of the catheter. The target movement model is a 3D periodic function over time. The input to the target movement model is the current respiratory stage, and the output is a 3D displacement vector. The current respiratory stage can be derived by comparing the current PST position relative to the chest movement model, and we can deduce at which stage we expect to see this PST positioning. In all respects, the respiratory model can be based on... Figure 4 Method 400 is used to generate it.

[0067] Figure 4 A method 400 for generating a respiratory model is illustrated. In box 401, first position data is received from a first EM sensor located at the distal portion of a catheter positioned near target lung tissue in the patient during a respiratory cycle. In box 402, a lung tissue movement model is generated based on the first position data according to the respiratory phase. In box 403, second position data is received from a second EM sensor positioned on the patient's chest during a respiratory cycle. In box 404, a chest movement model is generated based on the second position data according to the respiratory phase. Figure 4 As shown, boxes 401 and 402 can be executed in parallel with boxes 403 and 404. In each aspect, then, before ending at box 408, a lung breathing model is generated at box 406 based on the target tissue movement model and the chest movement model.

[0068] In various aspects, when lung tissue movement models and chest movement models are used to generate breathing models, the movement models can be weighted, for example, based on their accuracy. For instance, the weight of the lung tissue movement model can be greater than that of the chest movement model. The chest movement model can be used to derive the current breathing stage, and the breathing model can be used to derive the target displacement for a given breathing stage.

[0069] Refer again Figure 3 At box 308, current position data is received from the second EM sensor. The current position data can also be filtered in various ways as described herein. At box 310, the current respiratory cycle stage is estimated based on the respiratory model and the current position data. The current respiratory cycle stage can be any real number between zero and the respiratory cycle length. At box 312, the displacement of the target tissue is predicted based on the respiratory model and the current respiratory stage. Next, at box 316, the body coordinates near the target tissue are updated based on the displacement of the target tissue determined at box 312. Then, method 300 ends at box 318.

[0070] Figure 5 Another method 500 is demonstrated, using a respiratory model to update the position of the target and the catheter based on positional data from EM sensors positioned on the catheter and PST. At box 502, at the start of the setup phase, movement of the catheter positioned in the lungs is determined during at least one respiratory cycle of the patient. This movement can be determined based on positional data received from one or more EM sensors positioned at the distal portion of the catheter. At box 504, a movement model of the target is generated based on the catheter's movement. Box 504 may involve generating an initial 3D model of the target and surrounding tissue based on preoperative or intraoperative imaging, and a dynamic 3D model of the target based on the catheter's movement within the surrounding tissue.

[0071] At box 506, movement of at least one PST is determined during at least one respiratory cycle of the patient. The movement of the at least one PST can be determined based on positional data received from at least one PST positioned at the patient's chest. At box 508, a movement model of the patient's chest is generated based on the movement of the at least one PST. The movement model of the patient's chest can be a dynamic 3D model of all or part of the chest between the patient's neck and abdomen.

[0072] At box 510, where the usage phase begins, a real-time signal is received from at least one PST. The real-time signal can be filtered before use. At box 512, the respiratory phase is estimated based on the chest movement model and the real-time PST signal. At box 514, the target's movement compatible with the target's movement model is estimated based on the respiratory phase. Before ending at box 520, the positions of the target and catheter are updated at box 518 based on the target's compatible movement.

[0073] It should be understood that the various aspects disclosed herein can be combined in ways different from those specifically presented in the specification and drawings. It should also be understood that, by way of example, certain actions or events of any process or method described herein may be performed in a different order, may be added, combined, or omitted entirely (e.g., not all described actions or events may be necessary for implementing these techniques). Furthermore, although some aspects of this disclosure are described for clarity as being performed by a single module or unit, it should be understood that the techniques of this disclosure can be performed by a combination of units or modules associated with, for example, a medical device.

[0074] In one or more examples, the described techniques may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, these functions may be stored as one or more instructions or code on a computer-readable medium and executed by a hardware-based processing unit. Computer-readable media may include non-transitory computer-readable media, which corresponds to tangible media such as data storage media (e.g., RAM, ROM, EEPROM, flash memory, or any other medium that can be used to store desired program code in the form of instructions or data structures and that can be accessed by a computer).

[0075] Instructions can be executed by one or more processors, such as one or more digital signal processors (DSPs), general-purpose microprocessors, application-specific integrated circuits (ASICs), field-programmable arrays (FPGAs), or other equivalent integrated or discrete logic circuits. Accordingly, the term "processor" as used herein can refer to any of the above-described structures or any other physical structures suitable for implementing the described techniques. Furthermore, these techniques can be fully implemented in one or more circuit or logic elements.

[0076] The invention can be further described by referring to the following numbered paragraphs: 1. A method comprising: determining movement of a catheter disposed in a lung during at least one respiratory cycle of a patient; generating a movement model of a target based on the movement of the catheter; determining movement of at least one pulse head (PST) during at least one respiratory cycle of the patient; generating a movement model of the patient's chest based on the movement of the at least one PST; receiving a real-time PST signal from the at least one PST; estimating a respiratory phase based on the chest movement model and the real-time PST signal; estimating a movement of the target compatible with the movement model of the target based on the respiratory phase, thereby generating a compatible movement of the target; and updating the position of the target based on the compatible movement of the target. 2. The method according to paragraph 1, wherein the position of the target is updated in the coordinates of the patient's body. 3. The method according to paragraph 1 further includes updating the position of the catheter based on the updated position of the target. 4. The method described in paragraph 1 further includes updating the position of the target based on the breathing phase. 5. The method described in paragraph 1 further includes filtering the real-time PST signal to remove frequencies outside the normal respiratory rate range. 6. The method according to paragraph 1, wherein determining the movement of the catheter comprises: receiving position data from at least one EM sensor disposed at an end portion of the catheter during at least one respiratory cycle of the patient; and filtering the position data to remove position values ​​outside a predetermined range of position values. 7. The method according to paragraph 1, further comprising: determining that the amplitude of the catheter position data is greater than a threshold during a respiratory cycle; and not updating the position of the target in response to determining that the amplitude of the catheter position data is greater than the threshold during the respiratory cycle. 8. A method comprising: generating a lung breathing model based on a breathing phase using position data from a first electromagnetic (EM) sensor disposed at a distal portion of a catheter disposed in a patient's lung and from at least one second EM sensor disposed on the chest of the patient; receiving current position data from the at least one second EM sensor; estimating a current breathing phase based on the breathing model and the current position data; predicting a displacement of an average position of a target relative to the target based on the breathing model and the current breathing phase; and updating body coordinates near the target based on the displacement of the target. 9. The method according to paragraph 8, wherein the at least one second EM sensor is at least one PST. 10. The method according to paragraph 8, wherein generating the lung breathing model comprises: generating a chest movement model based on the location data from the first EM sensor according to the breathing stage; generating a target movement model based on the location data from the at least one second EM sensor according to the breathing stage; and combining the chest movement model with the target movement model to obtain the lung breathing model. 11. The method according to paragraph 8, wherein receiving the current location data, estimating the current breathing stage, predicting the displacement of the target, and updating the body coordinates are performed during a navigation procedure, a biopsy procedure, or an ablation procedure. 12. The method according to paragraph 8 further includes displaying a message to the user directing the conduit to the vicinity of the target. 13. The method according to paragraph 12 further includes displaying a message to the user that the conduit will not be moved. 14. The method according to paragraph 8 further includes simultaneously recording the location data from the first EM sensor and from the at least one second EM sensor during at least one respiratory cycle of the patient. 15. A system comprising: a catheter configured to be placed near target tissue in a patient's lung; a first electromagnetic (EM) sensor disposed at a distal portion of the catheter; at least one second EM sensor disposed on the patient's chest; a processor; and a memory storing instructions that, when executed by the processor, cause the system to: receive first position data from the first EM sensor; receive second position data from the at least one second EM sensor; generate a lung breathing model based on the first position data and the second position data according to a breathing phase; receive current position data from the at least one second EM sensor; estimate a current breathing phase based on the breathing model and the current position data; predict displacement of the target tissue based on the breathing model and the current breathing phase; and update body coordinates near the target tissue based on the displacement of the target tissue. 16. The system according to paragraph 15, wherein the instructions, when executed by the processor, further cause the system to perform the following operations: generate a lung tissue movement model based on the location data from the first EM sensor according to the respiratory phase; generate a chest movement model based on the location data from the at least one second EM sensor according to the respiratory phase; and generate the lung breathing model based on the target tissue movement model and the chest movement model. 17. The system according to paragraph 15, wherein the instructions, when executed by the processor, further cause the system to receive the current location data, estimate the current respiratory stage, predict the displacement of the target tissue, and update the body coordinates during a navigation procedure, biopsy procedure, or ablation procedure. 18. The system according to paragraph 15 further includes a display, wherein the instructions, when executed by the processor, further cause the display to show a message to a user that the catheter is navigated to the vicinity of the target tissue. 19. The system according to paragraph 15, wherein the instructions, when executed by the processor, further cause the system to simultaneously record the first location data and the second location data during at least one respiratory cycle of the patient. 20. The system according to paragraph 15, wherein the instructions, when executed by the processor, further cause the system to: register the coordinates of the at least one second EM sensor with the coordinates of the patient's body to generate sensor-body registration; determine that the movement of lung tissue is less than a threshold; and correct the sensor-body registration in response to determining that the movement of lung tissue is less than the threshold.

Claims

1. A method, comprising Determine the movement of the catheter placed in the lungs during at least one respiratory cycle of the patient; A movement model of the target is generated based on the movement of the catheter; Determine the movement of at least one PST during at least one respiratory cycle of the patient; A movement model of the patient's chest is generated based on the movement of at least one PST; Receive real-time PST signals from at least one PST; The respiratory phase is estimated based on the chest movement model and the real-time PST signal; Based on the breathing phase, a movement of the target compatible with the target's movement model is estimated, thereby generating a compatible movement of the target; as well as The target's position is updated based on the target's compatibility movement.

2. The method of claim 1, further comprising updating the position of the catheter based on the updated position of the target.

3. The method according to any one of the preceding claims, further comprising updating the position of the target based on the breathing phase.

4. The method according to any one of the preceding claims further includes filtering the real-time PST signal to remove frequencies outside the normal respiratory rate range.

5. The method according to any one of the preceding claims, wherein, Determining the movement of the catheter includes: Position data is received from at least one EM sensor located at the end portion of the catheter during at least one respiratory cycle of the patient; and The location data is filtered to remove location values ​​outside a predetermined range.

6. The method according to any one of the preceding claims further comprises: The amplitude of the catheter position data during the respiratory cycle is determined to be greater than a threshold; as well as The position of the target is not updated in response to determining that the amplitude of the catheter position data during the respiratory cycle is greater than a threshold.

7. A method, comprising A lung breathing model is generated based on position data from a first electromagnetic (EM) sensor located at the distal portion of a catheter placed in the patient's lungs and from at least one second EM sensor located on the patient's chest, according to the breathing phase. Receive current location data from the at least one second EM sensor; The current breathing stage is estimated based on the breathing model and the current location data; The displacement of the target's average position relative to the target is predicted based on the breathing model and the current breathing stage; as well as The body coordinates near the target are updated based on the target's displacement.

8. The method according to claim 7, wherein, Generating the lung breathing model includes: A chest movement model is generated based on the location data from the first EM sensor according to the breathing phase; A target movement model is generated based on the location data from the at least one second EM sensor according to the respiratory phase; and The chest movement model is combined with the target movement model to obtain the lung breathing model.

9. The method according to any one of the preceding claims, wherein, Receiving the current location data, estimating the current breathing stage, predicting the target's displacement, and updating the body coordinates are performed during the navigation procedure, biopsy procedure, or ablation procedure.

10. The method according to any one of the preceding claims further comprises simultaneously recording the location data from the first EM sensor and from the at least one second EM sensor during at least one respiratory cycle of the patient.

11. A system comprising A catheter, configured to be placed near target tissue in a patient's lung; A first electromagnetic (EM) sensor is disposed at the distal portion of the duct. At least one second EM sensor, said at least one second EM sensor being disposed on the patient's chest; processor; as well as A memory storing instructions that, when executed by the processor, cause the system to perform the following operations: Receive first location data from the first EM sensor; Receive second position data from the at least one second EM sensor; A lung breathing model is generated based on the first location data and the second location data according to the breathing stage; Receive current location data from the at least one second EM sensor; The current breathing stage is estimated based on the breathing model and the current location data; The displacement of the target tissue is predicted based on the respiratory model and the current respiratory stage. as well as The body coordinates near the target tissue are updated based on the displacement of the target tissue.

12. The system according to claim 11, wherein, When executed by the processor, the instructions further cause the system to perform the following operations: A lung tissue movement model is generated based on the location data from the first EM sensor according to the breathing stage; A chest movement model is generated based on the position data from the at least one second EM sensor according to the breathing phase; as well as The lung breathing model is generated based on the target tissue movement model and the chest movement model.

13. The system according to any one of the preceding claims, wherein, When executed by the processor, the instructions further enable the system to receive the current location data, estimate the current respiratory stage, predict the displacement of the target tissue, and update the body coordinates during navigation, biopsy, or ablation procedures.

14. The system according to any one of the preceding claims, wherein, When executed by the processor, the instructions further cause the system to simultaneously record the first location data and the second location data during at least one respiratory cycle of the patient.

15. The system according to any one of the preceding claims, wherein, When executed by the processor, the instructions further cause the system to perform the following operations: The coordinates of the at least one second EM sensor are registered with the coordinates of the patient's body, thereby generating sensor-body registration. Determine that the movement of lung tissue is less than a threshold; as well as The sensor is corrected for registration with the body in response to determining that the movement of lung tissue is less than the threshold.

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