Enhanced catheter navigation method and apparatus

Abstract

The invention is entitled "Enhanced catheter navigation method and apparatus". The invention provides methods, apparatus and systems for facilitating navigation of a catheter between a first location and a second location within a subject's body based on display of sequential images corresponding to the catheter's position at successive incremental times. Image generation includes sensing the catheter position to generate position data for each time increment. For each position P i , the corresponding position data is processed to correspondingly generate an image I i reflecting the catheter's position at time T i . Each image I i is continuously displayed at a time equal to T i +d, where d is an image processing visualization delay. In the event the catheter is displaced to a selected intermediate location between the first and second locations, processing of the position data is switched from execution by a first process associated with a first visualization delay to execution by a second process associated with a second, different visualization delay.

Description

Technical Field

[0001] This patent application provides systems, devices, and methods for improving medical procedures. Background Technology

[0002] Medical conditions such as cardiac arrhythmias (e.g., atrial fibrillation (AF)) are typically diagnosed and treated via in vivo procedures. For example, ablation is used to perform pulmonary vein electrical isolation (PVI) of the left atrium (LA) body for the treatment of AF. Pulmonary vein isolation and many other minimally invasive catheter insertion procedures require visualization and mapping of the in vivo surface.

[0003] Visualization of in vivo surfaces can be performed by mapping the propagation of excitation waves. Fluoroscopy, computed tomography (CT), magnetic resonance imaging (MRI), and other techniques may require more time or resources to provide visualization and mapping than desired. Furthermore, the graphical rendering used for visualizing in vivo surfaces may not include a sufficient amount of detail compared to other visualization modalities. Summary of the Invention

[0004] This document discloses methods, devices, and systems for medical procedures. In one example, a method is provided to facilitate navigation of the distal end of a catheter from the first position to the second position by referencing images reflecting the relative orientation of the distal end of the catheter as it is moved from a first position to a second position within the patient's body. The method includes displaying a series of images as the distal end of the catheter is moved from the first position to the second position based on selected time increments, each image corresponding to the orientation of the distal end of the catheter at consecutive time increments.

[0005] Image generation typically involves sensing the position of the distal end of the catheter at one or more selected frequencies to generate an image corresponding to the distal end of the catheter at time T for each time increment. i The position of time P i The location data of the conduit. For each orientation P i Processing corresponding to azimuth P i The location data is used to generate a corresponding reflection of the distal end of the catheter at time T. i Image of the orientation at time I i Each image I i equal to T i The time interval +d is displayed continuously, where d is the visualization delay, which includes processing corresponding to the azimuth P. i Location data to generate image I i The time spent. As described below, the exemplary processing mode is performed on a moving window of the data sample to produce image I. i This window includes time T i Samples at that time.

[0006] When the distal end of the catheter is displaced to a selected intermediate position between the first and second positions, the treatment corresponds to orientation P. i The location data is used to generate a corresponding result for each time increment, reflecting the distal end of the catheter at time T. i Image of the orientation at time I i The process switches from being executed by a first process to being executed by a second process, the first process being associated with a first visualization delay in generating a sequence image of catheter movement with a first feature, and the second process being associated with a second different visualization delay in generating a sequence image of catheter movement with a second different feature.

[0007] The different sequence image features generated by the first and second processes can be the degree of background motion (such as the motion of a beating heart) displayed in the sequence images reflecting the catheter orientation. An exemplary time increment of 16.7 ms is provided, allowing for the generation of images per second reflecting 60 orientations. i A series of 60 images, and the images can be displayed at 60 frames per second on a 60Hz monitor.

[0008] In cases where the intermediate and second positions are located within the subject's beating heart, one of the first and second processes can be selected, which is associated with a longer visualization delay in producing an image that removes heartbeat motion. This process may be referred to as the steady-state mode. In such cases, the other process of the first and second processes is associated with a shorter visualization delay in producing an image that reflects heartbeat motion. This process may be referred to as the triggered mode.

[0009] The method may include selecting a region including a second position, and subsequently sensing the entry orientation as an intermediate position when the distal end of the catheter enters the selected region, such that when the distal end of the catheter enters the selected region, the visualization process is automatically switched from being performed by a first process to being performed by a second process.

[0010] Alternatively, both the first and second processes can be implemented via a triggering mode, wherein one of the first and second processes is associated with a longer visualization delay in producing an image reflecting heartbeat motion, and the other of the first and second processes is associated with a shorter visualization delay in producing an image reflecting a larger amount of heartbeat motion produced by one of the processes.

[0011] Exemplary devices for performing such methods may include a monitor configured to display a series of images as the distal end of the catheter shifts from a first position to a second position based on selected time increments, each image corresponding to the orientation of the distal end of the catheter over a continuous period of time. A sensor is provided, configured to sense the position of the distal end of the catheter at one or more selected frequencies to generate, for each time increment, an image corresponding to the distal end of the catheter at time T as it shifts from the first position to the second position. i The position of time P i The duct position data. The processor is connected to the sensor and monitor and is configured to provide position data for each orientation P. i Processing corresponding to azimuth P i The location data is used to generate a corresponding reflection of the distal end of the catheter at time T. i Image of the orientation at time I i So that each image I i equal to T i +d seconds are displayed continuously, where d is the visualization delay, which includes processing corresponding to the azimuth P. i Location data to generate image I i The time spent.

[0012] To enable the display of different visualization modes, the processor is configured to switch the processing of location data from being performed by a first process to being performed by a second process, the first process being associated with a first visualization delay that produces a sequence of images of ductal movement with predetermined characteristics, and the second process being associated with a second different visualization delay that produces a sequence of images of ductal movement with different characteristics.

[0013] An exemplary processor configuration enables processing corresponding to orientation P when the distal end of the catheter is displaced to a selected intermediate position between a first position and a second position. i The location data is used to generate a corresponding reflection of the distal end of the catheter at time T. i Image of the orientation at time I i It is possible to switch from execution by the first process to execution by the second process associated with a second, different visualization delay.

[0014] The processor can be configured to execute different processes within the following processes according to a first process and a second process, such as a process associated with a relatively long visualization delay of generating an image with features de-identified from heartbeat motion when the first and second positions are located within the subject's beating heart, such as a stable mode as described herein; and a process associated with a relatively short visualization delay of generating an image with features reflecting heartbeat motion when the first and second positions are located within the subject's beating heart, such as a triggered mode as described herein.

[0015] A processor control can be provided, which is configured to allow the operator to manually select a specific visualization procedure, or to specify the anatomical region of the subject so that the processor automatically switches to the corresponding specific visualization procedure when the distal end of the catheter enters the specified anatomical region.

[0016] An exemplary sampling time increment of 16.7ms enables the processor to be configured to generate a series of 60 images per second reflecting 60 orientations, and an exemplary monitor is a 60Hz monitor configured to display images at 60 frames per second. Attached Figure Description

[0017] A more detailed understanding can be obtained by referring to the following description, which is given by way of example in conjunction with the accompanying drawings.

[0018] Figure 1 A diagram illustrating an exemplary system that can implement one or more features of the subject matter of this disclosure.

[0019] Figure 2 A flowchart for providing ultrasound slices based on catheter orientation.

[0020] Figure 3A Illustration of an ultrasonic transducer for collecting ultrasonic slices at various locations.

[0021] Figure 3B For located corresponding to Figure 3A A diagram showing the catheters at various locations in the direction of the [unclear].

[0022] Figure 4 This is a comparison graph of the simulation of Gaussian filtering versus the movement of a circular duct with fast (3Hz) noise periodicity.

[0023] Figure 5 This is a comparison graph of the simulation of rectangular filtering versus the movement of a circular duct with fast (3Hz) noise periodicity.

[0024] Figure 6 Comparison plots of simulations of Gaussian filtering with 27 coefficient windows relative to the upward shift of the noise duct. Detailed Implementation

[0025] According to specific embodiments of the subject matter disclosed in this invention, devices and methods are provided for visualizing catheters within a subject's body for medical procedures, diagnosis, mapping, or other purposes. Visualization includes sensing and collecting data, processing the data into images reflecting the catheter's orientation within the subject's body, and displaying a sequence of images on a video monitor, enabling a physician or other operator controlling the movement of the catheter to use the video images to assist in moving or otherwise manipulating the distal end of the catheter.

[0026] Because data processing into an image is not instantaneous, there is an inherent delay in generating an image of the catheter at orientation P within the subject's body at time T+d seconds, where d is the visualization delay, which includes the time spent processing data corresponding to the catheter's orientation P at time T. The smaller the visualization delay, the closer the image displayed to the catheter operator is to the real-time movement of the catheter within the subject's body performed by the operator.

[0027] According to the teachings of the present invention, more than one mode is employed to process the sensed data into images. In an exemplary embodiment, two types of catheter visualization modes are employed, which may be referred to as a stable mode and a triggered mode, respectively. Both modes are effective ways to navigate the tip of the catheter within the patient's body during medical procedures, provide orientation images, and accurately place the catheter.

[0028] In cases where catheter navigation will be performed, for example, within the beating heart of a patient to execute an ablation procedure, a stable processing mode can be employed to essentially generate an image of the distal end of the catheter within the patient's heart, where the heartbeat motion has been removed. This can be achieved by employing various filtering techniques to average the sensed data over a relatively large number of data samples, which in turn results in a relatively large visualization delay.

[0029] However, when navigating the catheter in certain anatomical regions or during challenging catheter manipulation, the catheter operator may desire a closer, real-time view of the catheter orientation, i.e., with a shorter visualization delay. Therefore, in the following exemplary implementation, three trigger modes for image processing are provided, wherein the associated visualization delay is shorter than that of the stable mode image processing. In each of the trigger modes, a sequence of images generated from the distal end of the catheter within the subject's beating heart will reflect some of the heartbeats according to the degree of data averaging, wherein the shortest averaging mode with the shortest visualization delay produces an image reflecting the largest amount of heartbeats, and the longest averaging mode with the longest visualization delay produces an image reflecting the smallest amount of heartbeats.

[0030] refer to Figures 1 to 3B The following paragraphs reflect examples of systems and methods for sensing and collecting anatomical and catheter orientation data and processing that data to construct images of both the subject's anatomy and the catheters positioned within it. Then, refer to... Figures 4 to 6 Various averaging patterns for filtering image data are discussed to provide the aforementioned different duct visualization patterns.

[0031] According to specific implementations of the disclosed subject matter, previously acquired ultrasound slices of a region of an organ can be displayed based on the current position of the catheter. Multiple ultrasound slices can be acquired and stored in memory. Multiple ultrasound slices can be acquired using an ultrasound transducer that is in multiple corresponding ultrasound transducer orientations, traversing different parts of the organ and acquiring multiple ultrasound slices. After acquiring and storing multiple ultrasound slices using the ultrasound transducer, a catheter can be inserted into the organ. The orientation of the catheter can be determined and may include catheter position and catheter orientation. Alternatively, if the catheter is an ultrasound transducer that collects ultrasound slices from the catheter orientation, the orientation of the catheter can be determined and may be based on voxels that can be occupied by ultrasound slices. For clarity, as disclosed herein, the current orientation of the catheter in real time can be determined based on catheter position and catheter orientation, or alternatively, based on the occupied voxels.

[0032] The orientation of the catheter can be compared with multiple ultrasound orientations corresponding to multiple ultrasound slices. A first ultrasound orientation corresponding to the catheter orientation can be determined, and a first ultrasound slice can be selected. The selected ultrasound slice can be provided for display. Notably, the selected ultrasound slice can display the region of the organ corresponding to the current orientation of the catheter, allowing healthcare professionals to visually view the region of the organ corresponding to the current orientation of the catheter by being provided with previously stored ultrasound slices.

[0033] Figure 1 This illustration shows an exemplary mapping system 20 that can implement one or more features of the subject matter of this disclosure. The mapping system 20 may include devices configured to obtain biometric data or ultrasound slices, such as catheter 40a and ultrasound transducer 40b, according to exemplary embodiments of the invention. The exemplary catheter 40a shown is a point catheter, but it should be understood that other catheters may be used to implement exemplary embodiments of the invention. The mapping system 20 includes a probe 21 having axes 22a and 22b that can be navigated by a medical professional 30 to body parts of a patient 28 lying on a bed 29, such as the heart 26. According to exemplary embodiments of the invention, multiple probes may be provided, such that a first probe is connected to catheter 40a and different probes are connected to ultrasound transducer 40b. However, for brevity, a single probe 21 is described herein, but it should be understood that probe 21 may represent multiple probes.

[0034] like Figure 1As shown, a medical professional 30 can insert shafts 22a and / or 22b through sheath 23 while manipulating the distal ends of shafts 22a and / or 22b using manipulators 32 near the proximal ends of catheters 40a and / or ultrasound transducers 40b and / or by flexing from sheath 23. As shown in illustration 25, catheters 40a and / or ultrasound transducers 40b can be fitted at the distal ends of shafts 22a and 22b, respectively. Catheters 40a and / or ultrasound transducers 40b can be inserted through sheath 23 in a collapsed state and can then be expanded within the heart 26.

[0035] According to an exemplary embodiment of the present invention, the ultrasound transducer 40b can be configured to obtain an ultrasound slice of the heart chambers of the heart 26. Illustration 45 shows the ultrasound transducer 40b within the heart chambers of the heart 26 in an enlarged view. As shown, the ultrasound transducer 40b can be attached to shaft 22b.

[0036] According to an exemplary embodiment of the invention, catheter 40a can be configured to obtain biometric data of the chambers of heart 26. Illustration 45 shows catheter 40a within the chambers of heart 26 in an enlarged view. As shown, catheter 40a may include a tip element 48 coupled to the body of the catheter. According to other exemplary embodiments of the invention, multiple elements may be connected via an elongation forming the shape of catheter 40a. Element 48 can be any element configured to obtain biometric data and can be an electrode, a transducer, or one or more other elements.

[0037] According to exemplary embodiments of the present invention, biometric data may include one or more of LAT, electrical activity, topology, bipolar mapping, dominant frequency, impedance, etc. Local excitation time can be a time point corresponding to the threshold activity of local excitation, calculated based on a normalized initial starting point. Electrical activity can be any applicable electrical signal that can be measured based on one or more thresholds and sensed and / or amplified based on signal-to-noise ratio and / or other filters. Topology can correspond to the physical structure of a body part or a portion of a body part, and can correspond to variations in the physical structure relative to different parts of the body part or relative to different body parts. Dominant frequency can be a frequency or frequency range that is prevalent in a part of a body part and can differ in different parts of the same body part. For example, the dominant frequency of the pulmonary veins of the heart can be different from the dominant frequency of the right atrium of the same heart. Impedance can be a resistance measurement at a given region of a body part.

[0038] like Figure 1As shown, probe 21, ultrasound transducer 40b, and catheter 40a can be connected to console 24. Console 24 may include processor 41 (such as a general-purpose computer) having suitable front-end and interface circuitry 38 for transmitting and receiving signals to and from catheter 40a and ultrasound transducer 40b, and for controlling other components of mapping system 20. In some exemplary embodiments of the invention, processor 41 may also be configured to receive biometric data and, based on the biometric data, generate rendering data of global and local views, as further disclosed herein. According to exemplary embodiments of the invention, the rendering data may be used to provide a medical professional 30 with renderings of one or more body parts (e.g., body part rendering 35) on display 27. According to exemplary embodiments of the invention, the processor may be located external to console 24 and may be located, for example, in a catheter, an external device, a mobile device, a cloud-based device, or may be a stand-alone processor. According to exemplary embodiments of the invention, ultrasound transducer 40b may provide ultrasound slices that can be stored in memory 42, as further disclosed herein. The ultrasonic transducer 40b can provide ultrasonic slices directly to the memory 42, or the ultrasonic slices can be provided to the processor 41 and the processor 41 can provide the ultrasonic slices to the memory 42.

[0039] As noted above, processor 41 may include a general-purpose computer that can be programmed with software to perform the functions described herein. The software may be downloaded to the general-purpose computer electronically, for example, via a network, or alternatively or additionally set and / or stored on a non-transitory tangible medium, such as magnetic storage, optical storage, or electronic storage. Figure 1 The exemplary configuration shown can be modified to implement exemplary embodiments of the present invention. Exemplary embodiments of the present invention can be applied similarly using other system components and settings. Additionally, the mapping system 20 may include additional components such as elements for sensing biometric patient data, wired or wireless connectors, processing and display devices, etc.

[0040] According to an exemplary embodiment of the invention, the display connected to the processor (e.g., processor 41) may be located in a remote location, such as a separate hospital or within a separate healthcare provider network. Additionally, the mapping system 20 may be part of a surgical system configured to acquire anatomical and electrical measurements of a patient's organs, such as the heart, and to perform cardiac ablation procedures. An example of such a surgical system is sold by Biosense Webster. system.

[0041] Mapping system 20 can also, and optionally, use ultrasound, computed tomography (CT), magnetic resonance imaging (MRI), or other medical imaging techniques known in the art to obtain biometric data, such as anatomical measurements of the patient's heart. Mapping system 20 can use catheters, electrocardiograms (EKG), or other sensors that measure the electrical properties of the heart to obtain electrical measurements. Figure 1 As shown, biometric data, including anatomical and electrophysiological measurements, can then be stored in the memory 42 of the mapping system 20. The biometric data can be transferred from the memory 42 to the processor 41. Alternatively or otherwise, a network 62 can be used to transfer the biometric data to a server 60, which may be local or remote. Similarly, a network 62 can be used to transfer ultrasound slices to a server 60, which may be local or remote.

[0042] Network 62 can be any network or system known in the art, such as an intranet, local area network (LAN), wide area network (WAN), metropolitan area network (MAN), direct connection or a series of connections, cellular telephone network, or any other network or medium capable of facilitating communication between the measurement system 20 and the server 60. Network 62 can be wired, wireless, or a combination thereof. Wired connections can be implemented using Ethernet, Universal Serial Bus (USB), RJ-11, or any other wired connection known in the art. Wireless connections can be implemented using Wi-Fi, WiMAX and Bluetooth, infrared, cellular networks, satellite, or any other wireless connection method known in the art. Additionally, several networks can operate independently or communicate with each other to facilitate communication within network 62.

[0043] In some cases, server 60 can be implemented as a physical server. In other cases, server 60 can be implemented as a public cloud computing provider (e.g., Amazon Web Services). () virtual server.

[0044] The console 24 can be connected to a body surface electrode 43 via cable 39, which may include an adhesive skin patch attached to the patient 28. The processor, in conjunction with a current tracking module, can determine the orientation coordinates of the catheter 40a and the ultrasound transducer 40b within a body part of the patient (e.g., the heart 26). The orientation coordinates may include the position and orientation of the catheter 40a and the ultrasound transducer 40b. The orientation coordinates may be based on impedance or electromagnetic field measured between the body surface electrode 43 and other electromagnetic components of the electrode 48 or catheter 40a. Similarly, the orientation coordinates may be based on impedance or electromagnetic field measured between the body surface electrode 43 and the ultrasound transducer 40b. Additionally or alternatively, a positioning pad may be located on the surface of the bed 29 and may be detachable from the bed 29. The orientation coordinates may be based on impedance or electromagnetic field measured between components of the electrode 48 and / or the ultrasound transducer 40b.

[0045] Processor 41 may include real-time noise reduction circuitry, typically configured as a field-programmable gate array (FPGA), followed by an analog-to-digital (A / D) ECG (electrocardiogram) or EMG (electromyography) signal conversion integrated circuit. Processor 41 may pass signals from the A / D ECG or EMG circuitry to another processor and / or may be programmed to perform one or more functions disclosed herein.

[0046] The console 24 may also include an input / output (I / O) communication interface that enables the console to transmit signals from electrode 48 and / or ultrasonic transducer 40b and electrode 43 or positioning pad, and / or to these components. Based on the signals received from electrode 48, ultrasonic transducer 40b, and / or electrode 43, processor 41 may generate rendering data (such as body part rendering 35) that enables a display (such as display 27) to render body parts.

[0047] During the procedure, processor 41 may facilitate the presentation of body part rendering 35 and / or ultrasound slice 37 to medical professional 30 on display 27 and store data representing body part rendering 35 and ultrasound slice 37 in memory 42. Memory 42 may include any suitable volatile and / or non-volatile memory, such as random access memory or hard disk drive. In some exemplary embodiments of the invention, medical professional 30 may use one or more input devices, such as touchpad, mouse, keyboard, gesture recognition device, etc., to manipulate body part rendering 35 and / or ultrasound slice 37. For example, the input device may be used to change the orientation of catheter 40a such that rendering 35 is updated and different ultrasound slices 37 are provided based on the updated orientation, as disclosed herein. In another exemplary embodiment of the invention, display 27 may include a touchscreen that may be configured to accept input from medical professional 30 in addition to presenting body part rendering 35 and ultrasound 37 (including global and local views).

[0048] According to an exemplary embodiment of the present invention, an ultrasound transducer can be configured to acquire ultrasound slices at various locations within an organ. The ultrasound transducer can be connected to... Figure 1 The ultrasound transducer 40b is the same as or similar to this one. Ultrasonic transducers can be inserted into internal organs, such as... Figure 1 The ultrasound transducer can be inserted into a chamber of an organ, such as the heart chamber of the heart 26. The ultrasound transducer can be configured to automatically acquire ultrasound slices at predetermined time intervals (e.g., one ultrasound slice per millisecond), or it can be configured to acquire ultrasound slices based on the orientation and / or movement of the ultrasound transducer. For example, the ultrasound transducer can be configured to acquire up to a given number of ultrasound slices (e.g., three ultrasound slices) based on each orientation of the ultrasound transducer. Thus, the ultrasound transducer can be configured to acquire multiple ultrasound slices for each ultrasound transducer orientation. According to an exemplary embodiment of the invention, the processor, such as... Figure 1 The processor 41 can be configured to select a single ultrasound slice from multiple ultrasound slices at the same ultrasound orientation. The processor can select a single ultrasound slice based on one or more factors, such as ultrasound slice quality, ultrasound transducer stability during ultrasound slice acquisition, signal-to-noise ratio, etc. For example, ultrasound slice quality can be determined based on the detection boundary of the organ within the slice (compared to the free space of the organ within the slice (e.g., blood pool)). Based on the selection and factors described herein, a second ultrasound slice at the same ultrasound orientation can replace the first ultrasound slice.

[0049] As used herein, ultrasound orientation may correspond to ultrasound transducer orientation or ultrasound slice orientation, as further described herein. Ultrasound transducer orientation may be the orientation of the ultrasound transducer when acquiring a given ultrasound slice. Ultrasound transducer orientation may include ultrasound transducer position (e.g., coordinates) and ultrasound transducer orientation (e.g., angle), as further disclosed herein. Ultrasound slice orientation may correspond to the area, volume, or voxel occupied by the ultrasound slice. As used herein, catheter orientation may correspond to catheter position (e.g., coordinates) and orientation (e.g., angle), or it may correspond to catheter slice orientation, as further disclosed herein.

[0050] According to an exemplary embodiment of the present invention, the orientation of an ultrasound transducer or catheter may include the location and orientation of the corresponding ultrasound transducer or catheter. The location (i.e., the orientation of the ultrasound transducer or catheter) may be stored as or include coordinates, which may be represented as Cartesian coordinates, polar coordinates, voxel coordinates, or any other applicable coordinates, or combinations thereof. The location may be relative to a reference point, which may be located inside the body, inside an internal organ, inside an internal organ cavity, or outside the body. The location may be based on information from the ultrasound transducer, catheter, or body surface electrodes (e.g., [insert reference here]). Figure 1 The location is determined by signals (e.g., electromagnetic signals) from body surface electrodes 43), positioning pads, or other location-based components.

[0051] Orientation can be based on a reference point (e.g., tip) of the ultrasound transducer or catheter, such that the orientation indicates the direction in which the reference point of the ultrasound transducer and / or catheter is facing. It should be understood that while reference points are specifically listed herein, a reference point can be a set of points, such as a line. A reference point can be any part of the ultrasound transducer or catheter, such as a distal point, a proximal point, or any other applicable point. Orientation can be stored as or include angles, phases, directions, axes, inclinations, or combinations thereof.

[0052] Figure 2 A flowchart 200 illustrates a process for providing previously stored ultrasound slices from multiple previously stored ultrasound slices based on catheter orientation.

[0053] exist Figure 2 At step 210 of the process shown, when the ultrasonic transducer is in the first ultrasonic transducer orientation, a first ultrasonic slice can be received from the ultrasonic transducer. The first ultrasonic slice acquired when the ultrasonic transducer is in the first orientation can be one of multiple slices acquired when the ultrasonic transducer is in the first orientation. As disclosed herein, the processor can designate a single ultrasonic slice from multiple ultrasonic slices as the first ultrasonic slice for a given ultrasonic orientation based on one or more of the following: ultrasonic slice quality, ultrasonic transducer stability during ultrasonic slice acquisition, signal-to-noise ratio, etc.

[0054] Figure 3A An example illustration of a cardiac chamber 300 with an ultrasound transducer 310 in multiple orientations 310a, 310b, and 310c is shown. Figure 3A As shown, and according to Figure 2 In step 210 of the process shown, when the ultrasonic transducer is in the first ultrasonic transducer orientation 310a, a first ultrasonic slice 321a can be received from the ultrasonic transducer 310. The first ultrasonic transducer orientation 310a can be represented by position (e.g., coordinates) and orientation (e.g., angle and tilt) such that the slice 321a is associated with the first ultrasonic transducer orientation 310a.

[0055] exist Figure 2 At step 220 of the process shown, the first ultrasonic slice and the orientation of the first ultrasonic transducer corresponding to the first ultrasonic slice can be stored in any suitable storage medium such as Figure 1 The first ultrasound slice can be stored in memory 42. It can be stored as an image file, a video file, or any other file that allows the first ultrasound slice to be rendered at some point after it has been acquired by the ultrasound transducer. The orientation of the first ultrasound transducer can be stored within the same file or filegroup containing the first ultrasound slice, or it can be stored in a separate storage location different from the first ultrasound slice, such that the stored orientation of the first ultrasound transducer and the first ultrasound slice are associated with each other by any applicable means such as pointers, lookup tables, etc. Figure 3A The example provided shows that the first ultrasonic slice 321a and the first ultrasonic transducer orientation 310a can be stored in memory.

[0056] exist Figure 2 At step 230 of the process shown, when the ultrasonic transducer is in the second ultrasonic transducer orientation, a second ultrasonic slice can be received from the ultrasonic transducer. The second ultrasonic slice acquired when the ultrasonic transducer is in the second orientation can be one of multiple slices acquired when the ultrasonic transducer is in the second orientation, as disclosed herein. A single slice obtained from multiple slices acquired when the ultrasonic transducer is in the second orientation can be designated as the second ultrasonic slice. For example... Figure 3A As shown, and according to Figure 2 In step 230 of the process shown, when the ultrasonic transducer is in the second ultrasonic transducer orientation 310b, a second ultrasonic slice 321b can be received from the ultrasonic transducer 310. The second ultrasonic transducer orientation 310b can be represented by position (e.g., coordinates) and orientation (e.g., angle and tilt) such that slice 321b is associated with the first ultrasonic transducer orientation 310b.

[0057] exist Figure 2At step 240 of the process shown, the second ultrasonic slice and the orientation of the second ultrasonic transducer corresponding to the second ultrasonic slice can be stored in any suitable storage medium, such as in a manner similar to that disclosed according to step 220. Figure 1 The first and second ultrasound slices are stored in memory 42. Although steps 210 to 240 disclose the first and second ultrasound slices for simplicity, it should be understood that one or more additional ultrasound slices can be acquired and stored. For example, as... Figure 3A As shown, ultrasonic slices 321c can be acquired when the ultrasonic transducer 310 is in ultrasonic transducer orientation 310c, and the corresponding data can be stored in the memory.

[0058] exist Figure 2 At step 250 of the process shown, the first catheter orientation corresponding to the internal catheter can be received. The internal catheter can be connected to... Figure 1 The catheter 40a is the same as or similar to the one used, and can be inserted into the body cavity when the ultrasound transducer is located in the body cavity or after the ultrasound transducer has been removed from the body cavity. The first catheter orientation can be received via any suitable means, including via electromagnetic signals between electrodes on the catheter and a positioning pad, electromagnetic signals between electrodes on the catheter and body electrodes, etc. The first catheter orientation can include position and orientation as disclosed herein. According to a specific implementation of this exemplary embodiment, the first catheter orientation can have the same characteristics as in... Figure 2 The ultrasonic transducer orientations stored at steps 220 and 240 are in the same format. According to another embodiment, the first catheter orientation may have a different format than the ultrasonic transducer orientations stored at steps 220 and 240, but can be converted so that they can be associated with the format of the ultrasonic transducer orientations stored at steps 220 and 240.

[0059] Figure 3B The diagram shows a catheter 311 in various orientations 311a, 311b, and 311c. Figure 3A Example illustration of a 300-cell heart chamber. Figure 3B As shown, and according to Figure 2 Step 250 of the process shown can receive the catheter's orientation when the catheter is in the first orientation 311a. The catheter's orientation can be updated at predetermined time intervals or based on the detection of catheter movement.

[0060] exist Figure 2At step 260 of the process shown, it can be determined that the first catheter orientation received at step 250 corresponds to the first ultrasonic transducer orientation received at step 210 and stored at step 220. Although for simplicity, the first catheter orientation received at step 250 is described as corresponding to the first ultrasonic transducer orientation received at step 210, it should be understood that the catheter orientation may correspond to any of the ultrasonic transducer orientations.

[0061] Determining that the first catheter orientation received at step 250 corresponds to the first ultrasound transducer orientation can be based on comparing the received catheter orientation (i.e., step 250) with stored ultrasound transducer orientations (i.e., steps 220 and 240). According to an exemplary embodiment of the invention, the catheter orientation can be received in the same format as the stored ultrasound transducer orientations. For example, the catheter orientation can include a catheter position that can be received as a set of coordinates, and can also include a catheter orientation that can be received as an angle and inclination. For example, the catheter orientation can include x, y, and z coordinates (4 mm, 8 mm, 1 mm) of its position relative to a coordinate reference point (such as an external patch or a region within an internal organ). The catheter orientation can include a 44-degree angle corresponding to the horizontal angle of the catheter reference point (e.g., the tip), and a 14-degree inclination corresponding to the vertical angle of the catheter reference point. According to this example, the catheter orientation can be represented as (4, 8, 1, 44, 14). At step 260, the catheter orientation can be compared with multiple ultrasound transducer orientations that can be in the same format. For example, the first ultrasonic transducer orientation stored in step 220 could be (5,8,1,44,14), and the second ultrasonic transducer orientation stored in step 240 could be (6,8,1,44,14). It is possible to calculate which of the stored ultrasonic transducer orientations is closest to the received catheter orientation. Continuing this example, since the catheter orientation (4,8,1,44,14) differs from the first ultrasonic transducer orientation (5,8,1,44,14) by only 1 mm, it can be determined that the first ultrasonic transducer orientation corresponds to the catheter orientation, because the second ultrasonic transducer orientation (6,8,1,44,14) differs from the catheter orientation by 2 mm.

[0062] According to an exemplary embodiment of the invention, the received catheter orientation may be in a different format than a plurality of stored ultrasound transducer orientations (e.g., polar coordinates instead of Cartesian coordinates). It should be understood that one or more of the different formats may be converted so that the two sets of orientations (catheter orientation and ultrasound transducer orientation) can be compared with each other to determine which of the plurality of ultrasound transducer orientations corresponds to the catheter orientation.

[0063] According to an exemplary embodiment of the invention, a correlation threshold can be provided such that if the difference between the catheter orientation and the orientations of all available ultrasound transducers is greater than the correlation threshold, it is determined that no ultrasound transducer orientation corresponds to the catheter orientation. Therefore, at step 270, as further disclosed herein, no ultrasound slice can be displayed. It is noteworthy that in this case, there may not be an ultrasound slice that would visually display the region corresponding to the current catheter orientation, and therefore no ultrasound slice can be provided at step 270.

[0064] exist Figure 2 At step 270 of the illustrated process, an ultrasound slice (e.g., a first ultrasound slice) can be provided, associated with the ultrasound transducer orientation (e.g., a first ultrasound transducer orientation) determined at step 260 to correspond to the catheter orientation. The ultrasound slice can be displayed via a display such as... Figure 1 The ultrasound slices are provided to a display 27. Alternatively, the ultrasound slices can be provided to an external display, such as via a network 62 and a server 60, so that the ultrasound slices can be displayed at a remote location.

[0065] To navigate the distal end of a catheter, such as catheter 40a, it is generally desirable to display a sequence of images of the catheter's orientation to the physician 30 on monitor 27. In cases where, for example, an ablation procedure will be performed, navigation involves moving the distal end of the catheter within the heart.

[0066] As described above, the exemplary system is configured such that operator 30 can select, via system console 24, any of several processing modes that processor 41 is configured to execute to generate sequential images of catheter orientation, these modes reflecting different degrees of cardiac activity. In this example, the selection controls in console 24 are configured such that operator 30 can manually select a specific mode upon selection, or can specify an anatomical region of the subject so that the processor automatically switches to the corresponding specific mode if the distal end of the catheter enters the specified anatomical region.

[0067] To implement different visualization modes, in this example, processor 41 is configured to average samples of the catheter's sensed orientation data using a selected filter. Each mode employs a different moving window for the sample orientation. Therefore, the mode using the smallest window has the shortest visualization delay and produces an image reflecting the largest amount of heartbeat motion. The mode using the largest window has the longest visualization delay and produces an image reflecting the smallest amount of heartbeat motion. The latter is a stable mode, where there is essentially no heartbeat motion reflected in the displayed sequence of images.

[0068] In an exemplary embodiment, processor 41 is configured to implement four different modes for generating the displayed sequence images of the duct orientation: a stable mode in which the heartbeat motion is substantially completely removed; and three triggered modes in which different degrees of heartbeat motion are reflected in the displayed sequence images. In all four modes, a sample size of the data accumulated over 16.7 ms (i.e., one-sixtieth of a second) is combined with Gaussian filtering.

[0069] For the stable mode, a Gaussian filter with 61 coefficients is used to generate a sequence of images that does not reflect heartbeat motion, with an associated visualization delay of approximately 500 ms. This Gaussian filter implements a 60-directional movement window, equivalent to a one-second window. For a triggered mode, Mode 1, a Gaussian filter with 27 coefficients is used to generate a sequence of images, with an associated visualization delay of approximately 216 ms. This Gaussian filter implements a 26-directional movement window, equivalent to a window of approximately 430 ms. For a second triggered mode, Mode 2, a Gaussian filter with 21 coefficients is used to generate a sequence of images, with an associated visualization delay of approximately 166 ms. This Gaussian filter implements a 20-directional movement window, equivalent to a window of approximately 330 ms. For a third triggered mode, Mode 3, a Gaussian filter with 13 coefficients is used to generate a sequence of images, with an associated visualization delay of approximately 100 ms. This Gaussian filter implements a 12-directional movement window, equivalent to a window of approximately 200 ms.

[0070] Although other filtering techniques can be used, Gaussian filtering is preferred. Figure 4 Comparison graphs are provided for simulations of four visualization modes using Gaussian filtering relative to the movement of a circular duct with fast (3Hz) noise periodicity. Figure 5 Comparison plots are provided for four corresponding visualization modes using rectangular filtering relative to the simulation of a fast (3Hz) noise periodic circular duct movement.

[0071] Rectangular filtering over-averages due to the equal weighting of different portions of the period that cancel each other out, especially in mode 2 filters (21 samples) that match the period of the moving period. Gaussian filtering is unaffected by this. The duct trace is shifted to allow for easy observation. The "stable" mode output is also significantly attenuated for this particular signal.

[0072] Figure 6 The relative smoothness of the sequence images produced by the mode 1 triggered processing is shown by providing a comparative plot of the simulation of the upward shift of the noise conduit with a mode 1 Gaussian filter having 27 coefficient windows.

[0073] While specific exemplary filtering modes have been described above, processor 41 can be configured to implement visualization modes with other features. In some systems, it may be desirable to vary the sampling frequency and / or size of the moving window filter to achieve a stable mode. Generally, for a filtering mode based on 16.7 ms sampling, it is preferable to provide a mode that includes applying a Gaussian filter with a moving window ranging from 12 to 60 azimuths, such that the visualization delay associated with the process is in the corresponding range of approximately 100 ms to approximately 500 ms.

[0074] For example, in the execution of a cardiac ablation procedure to be performed at a predetermined ablation site within the patient's heart, physician 30 navigates the distal end of the ablation catheter from its initial position to the ablation site to perform the ablation. For different segments of catheter movement, physician 30 can select a visualization mode for generating sequential images to assist physician 30 in guiding catheter movement.

[0075] For example, physician 30 may refer to the displayed sequence images of catheter movement generated by the stable visualization mode to select whether to move the catheter from an initial position within the patient's heart to an intermediate position. Physician 30 may then refer to the displayed sequence images of catheter movement generated by a selected mode in the trigger visualization mode to select whether to move the catheter further from the intermediate position to the ablation position.

[0076] Instead of moving the catheter directly from the intermediate position to the ablation site by referring to the displayed sequence images of catheter movement generated by the selected trigger visualization mode, the physician 30 may refer to the displayed sequence images of catheter movement generated by the selected trigger visualization mode to decide whether to move the catheter from the intermediate position only to a second intermediate position. The physician 30 may then refer to the displayed sequence images of catheter movement generated by a different or stable visualization mode in the trigger visualization mode to select whether to move the catheter further from the second intermediate position to the ablation site.

[0077] Generally, this process can be described as a method for facilitating the navigation of the distal end of the catheter from the first position to the second position by referring to images reflecting the relative orientation of the distal end of the catheter as it moves from a first position to a second position within the subject's body. The method includes displaying a series of images as the distal end of the catheter moves from the first position at time T0 to the second position at time T0+X seconds based on selected time increments, each image corresponding to the orientation of the distal end of the catheter at consecutive time increments.

[0078] Navigating the distal end of the catheter from the first position to the second position does not require continuous movement of the distal end of the catheter, but can instead include 30 cycles in which the physician does not move the catheter.

[0079] Image generation typically involves sensing the position of the distal tip of the catheter at one or more selected frequencies to generate an image corresponding to the distal tip of the catheter at time T for each time increment from T0 seconds to T0+X seconds. i The position of time P i The location data of the conduit. For each orientation P i Processing corresponding to azimuth P i The location data is used to generate a corresponding reflection of the distal end of the catheter at time T. i Image of the orientation at time I i Each image I i equal to T i The time interval +d is displayed continuously, where d is the visualization delay, which includes processing corresponding to the azimuth P. i Location data to generate image I i The time spent. As described above, processing by the exemplary processing mode is performed on the moving window of the data sample to produce image I. i This window includes time T i Samples at that time.

[0080] In the case where the distal end of the catheter shifts to a selected intermediate position between the first and second positions at time T0+(XY) seconds, for each T from T0 seconds to T0+(XY) seconds... i Processing corresponding to azimuth P i The location data is used to generate a corresponding reflection of the distal end of the catheter at time T. i Image of the orientation at time I i The process switches from execution by a first process to execution by a second process, the first process being associated with a first visualization delay for generating sequence images of catheter movement with a first characteristic, and the second process being associated with a second different visualization delay for generating sequence images of catheter movement with a second different characteristic, thereby for each T from T0+(XY) seconds to T0+X seconds. i The generation corresponds to the reflection of the distal end of the catheter at time T. i The orientation of the hour P i Image I i The different sequence image features produced by the first and second processes can be the degree of background motion (such as the motion of a beating heart) displayed in the sequence images in the catheter orientation.

[0081] As described above, the exemplary time increment is 16.7 ms, resulting in the generation of P values ​​reflecting 60 azimuths per second. i A series of 60 images, and the images can be displayed at 60 frames per second on a 60Hz monitor.

[0082] In cases where the intermediate and second positions are located within the subject's beating heart, one of the first and second processes can be selected, which is associated with a longer visualization delay in generating an image that removes heartbeat motion, such as the stable mode described above. In this case, the other process in the first and second processes is associated with a shorter visualization delay in generating an image that reflects heartbeat motion, such as one of the triggering modes described above.

[0083] In an exemplary implementation, when, for example, physician 30 observes that the distal end of the catheter is in the desired intermediate position, the physician can manually switch between the first and second procedures. Alternatively, physician 30 can select a region where the switching between the first and second procedures is automatic when the catheter is sensed to have entered the selected region. For example, physician 30 can select a specific region in the patient's heart that includes a difficult-to-reach ablation site. A stable mode procedure can be implemented when the catheter has shifted before reaching the entry point of the selected region. When the catheter is sensed to have entered the selected region, in this case, the visualization mode will automatically switch to a triggered mode procedure to provide physician 30 with a faster visualization of the catheter movement from that entry point to the difficult-to-reach ablation site.

[0084] Both the first and second processes can be implemented via a triggering mode, wherein one of the first and second processes is associated with a longer visualization delay in producing an image reflecting heartbeat motion, and the other of the first and second processes is associated with a shorter visualization delay in producing an image reflecting a larger amount of heartbeat motion produced by that one process.

[0085] Generally speaking, devices that perform such methods can include those described above. Figure 1 The monitor shown is configured to display a series of images as the distal end of the catheter shifts from a first position to a second position based on selected time increments, each image corresponding to the orientation of the distal end of the catheter over a continuous time period. A sensor, as described above, configured to sense the position of the distal end of the catheter at one or more selected frequencies, is provided to generate, for each time increment, an image corresponding to the distal end of the catheter at time T as it shifts from the first position to the second position. i The position of time P i The location data of the conduit. A processor, such as processor 41, is connected to the sensor and monitor and is configured for each orientation P. i Processing corresponding to azimuth P i The location data is used to generate a corresponding reflection of the distal end of the catheter at time T. i Image of the orientation at time I i So that each image I i equal to Ti +d seconds are displayed continuously, where d is the visualization delay, which includes processing corresponding to the azimuth P. i Location data to generate image I i The time spent.

[0086] To enable the display of different visualization modes, the processor is configured to switch the processing of location data from being performed by a first process to being performed by a second process, the first process being associated with a first visualization delay that produces a sequence of images of ductal movement with predetermined characteristics, and the second process being associated with a second different visualization delay that produces a sequence of images of ductal movement with different characteristics.

[0087] An exemplary processor configuration enables processing corresponding to orientation P when the distal end of the catheter is displaced to a selected intermediate position between a first position and a second position. i The location data is used to generate a corresponding reflection of the distal end of the catheter at time T. i Image of the orientation at time I i It is possible to switch from execution by the first process to execution by the second process associated with a second, different visualization delay.

[0088] The processor can be configured to execute different processes within the following processes according to a first process and a second process, the processes including: a process associated with a relatively long visualization delay for generating an image de-heartbeat motion when the first position and the second position are located within the subject's beating heart, such as the stable mode described above; and a process associated with a relatively short visualization delay for generating an image reflecting heartbeat motion when the first position and the second position are located within the subject's beating heart, such as the triggered mode described above.

[0089] The sampling time increment is preferably selected as 16.7ms, such that the processor is configured to generate a series of 60 images per second reflecting 60 directions, and the monitor is a 60Hz monitor configured to display images at 60 frames per second.

[0090] Any of the functions and methods described herein can be implemented in a general-purpose computer, processor, or processor core. By way of example, suitable processors include general-purpose processors, special-purpose processors, conventional processors, digital signal processors (DSPs), multiple microprocessors, one or more microprocessors associated with a DSP core, controllers, microcontrollers, application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), any other type of integrated circuit (IC), and / or state machines. Such processors can be manufactured by configuring the manufacturing process using the results of processing hardware description language (HDL) instructions and other intermediate data, including netlists (such instructions can be stored on a computer-readable medium). The result of this processing can be a maskwork, which is subsequently used in a semiconductor manufacturing process to manufacture processors implementing the features of this disclosure.

[0091] Any of the functions and methods described herein may be implemented in computer programs, software, or firmware incorporated into a non-transitory computer-readable storage medium for execution by a general-purpose computer or processor. Examples of non-transitory computer-readable storage media include read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media (e.g., internal hard disks and removable disks), magneto-optical media, and optical media (e.g., CD-ROMs and DVDs).

[0092] It should be understood that many variations are possible based on the disclosure herein. Although features and elements have been described above in specific combinations, each feature or element may be used alone without other features and elements, or in various combinations with or without other features and elements.

Claims

1. An apparatus for facilitating navigation of the distal catheter tip from the first position to the second position within the subject by referring to an image reflecting the relative orientation of the distal catheter tip when the distal catheter tip is displaced from a first position within the subject to a second position within the subject, the apparatus comprising: A monitor configured to display a series of images as the distal catheter tip moves from the first position to the second position based on a selected time increment, each image corresponding to the orientation of the distal catheter tip over a continuous time interval; A sensor, configured to sense the position of the distal end of the catheter at one or more selected rates, to generate a time increment corresponding to the distal end of the catheter at time T as the distal end of the catheter shifts from the first position to the second position. i The orientation P i The location data of the catheter; A processor, connected to the sensor and the monitor, and configured for each orientation P i Processing corresponding to the orientation P i The location data is used to generate a corresponding reflection of the distal catheter tip at time T. i Image I of the aforementioned orientation i So that each image I i equal to T i The display is continuous for +d seconds, where d is the visualization delay, which includes processing corresponding to the orientation P. i The location data is used to generate the image I. i The time spent; as well as The processor is configured to switch the processing of the corresponding location data from being performed by a first process to being performed by a second process, the first process being associated with a first visualization delay for generating a sequence of images of catheter movement with predetermined characteristics, and the second process being associated with a second, different visualization delay for generating a sequence of images of catheter movement with different characteristics, such that: In the case where the distal catheter tip is displaced to a selected intermediate position between the first and second positions, processing is performed corresponding to orientation P. i The location data is used to generate a corresponding reflection of the distal catheter tip at time T. i Image I of the aforementioned orientation i Capable of switching from execution by the first process to execution by the second process; and also includes A processor control configured to enable an operator to specify an anatomical region of a subject, wherein the processor automatically switches to the appropriate specific procedure when the distal end of the catheter enters the specified anatomical region.

2. The device of claim 1, wherein the processor is configured to perform different processes comprising the following processes according to the first process and the second process: The process associated with generating a relatively long visualization delay in which the image of the heartbeat motion is removed when the intermediate position and the second position are located within the beating heart of the subject; and The process associated with a relatively short visualization delay in generating an image reflecting heartbeat motion when the intermediate position and the second position are located within the subject's beating heart; and It also includes a user-operable switch configured to switch the processor's mode from executing one of the different processes to executing another of the different processes.

3. The device according to claim 2, wherein the time increment is selected as 16.7 ms, such that the processor is configured to generate 60 azimuth P responses per second. i A series of 60 images.

4. The device of claim 3, wherein the processor is configured to perform different processes comprising the following processes according to the first process and the second process: This includes the process of generating an image in which heartbeat motion is removed by applying a Gaussian filter with a moving window in 60 directions, such that the visualization delay associated with the process is 500ms; and This includes the process of applying a Gaussian filter with a moving window in the range of 12 to a maximum of 60 azimuths, such that the visualization delay associated with the corresponding process is in the range of 100 ms to a maximum of 500 ms, to generate an image reflecting heartbeat motion.

5. The device of claim 4, wherein the process of generating an image reflecting heartbeat motion comprises: This includes applying a Gaussian filter with a 12-position moving window to make the visualization delay associated with the process 100ms; This includes applying a Gaussian filter with a 20-position moving window to achieve a visualization delay of 166 ms associated with the process; and This includes applying a Gaussian filter with a 26-position moving window to achieve a visualization delay of 216 ms associated with the process.

6. The device of claim 3, wherein the monitor is a 60Hz monitor configured to display images at 60 frames per second.

Images