Systems and methods for organizational analysis and visualization

Abstract

The present invention relates to methods, systems, and devices for providing tissue analysis and visualization using contrast-enhanced ultrasound. An aspect of the present invention includes a system for providing tissue analysis and visualization, comprising an imaging device and a console operably associated therewith. In particular, the imaging device comprises a console comprising a hardware processor coupled to non-transient computer-readable memory containing instructions, the instructions being executable by the processor to cause the console to receive three-dimensional (3D) ultrasound image data from the imaging device and to dynamically reconstruct multiple images from the 3D image data.

Description

Technical Field

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[0001] (Cross - Reference to Related Applications) This application claims the priority and benefit of U.S. Provisional Application No. 63 / 525,262, filed on July 6, 2023, the content of which is incorporated herein by reference in its entirety.

[0002] (Field of the Invention) The present invention generally relates to ultrasonic imaging, and more specifically, to systems and devices for providing tissue analysis and visualization using contrast - enhanced ultrasound.

Background Art

[0003] (Background) Ultrasonic imaging is a medical imaging technique for imaging organs and soft tissues within the human body. Ultrasonic images are produced based on the reflection of high - frequency sound waves from body structures. The intensity (amplitude) of the sound signal, combined with the time it takes for the wave to travel through the body, provides the information necessary to produce an image.

[0004] Ultrasonic imaging can be useful for physicians to evaluate, diagnose, and treat various medical conditions. When making a diagnosis based on an ultrasound examination, the physician must rely on proper image quality, access to appropriate views, and sufficient quantification of all relevant structures and flows.

[0005] For example, catheter-based intravascular ultrasound imaging techniques used within blood vessels (e.g., intravascular ultrasound (IVUS) or intracardiac echocardiography (ICE)) are generally performed using two-dimensional (2D) ultrasound imaging. In an IVUS / ICE imaging system, an ultrasound transducer assembly is attached to the distal end of a catheter. The catheter is carefully maneuvered through the patient's body to the area of ​​interest, such as within the coronary arteries (in the case of IVUS) or the right atrium (in the case of ICE). The transducer assembly transmits ultrasound waves and receives echoes from those waves. The received echoes are then converted into electrical signals and transmitted to a processing device, where the resulting ultrasound image of the area of ​​interest may be displayed.

[0006] In typical ultrasound systems configured to visualize internal body regions, dynamic forces are often employed, resulting in dynamic movement of the body region over time. These dynamic forces and movement make it difficult to stabilize the internal imaging device and generate consistent and accurate images, especially when imaging of structures cannot be enabled in real time (e.g., >20 Hz). As a result, captured images often lack the necessary quality required to prescribe appropriate treatment or therapy. Due to the dynamic forces and movement at play, internal real-time imaging is limited to small two-dimensional areas or confined three-dimensional volume regions, respectively.

[0007] For certain treatments such as catheter ablation, accurately capturing the visual representation of the anatomical structure of interest is paramount to the success of the procedure. Catheter ablation is a treatment in which energy is applied to cardiac tissue to create scars or ablation lesions that prevent or interrupt the transmission of abnormal electrical signals. Catheter ablation forms an integral part of the management of cardiac arrhythmias, including supraventricular tachycardia (SVT), atrial flutter (AFL), atrial fibrillation (AF), and ventricular tachycardia (VT). The relatively low efficacy of AF treatment is likely due to limitations in mapping, an incomplete understanding of the driving mechanisms of arrhythmias, and, most importantly, the inability to create transmural and durable ablation lesions.

[0008] The success of catheter ablation requires not only the precise localization of the arrhythmogenic substrate but also its complete and permanent elimination without causing associated injury. The ablation effect depends on several factors, including the applied power, the quality of electrical contact, local tissue properties, the presence of blood flow adjacent to the tissue surface, and the effect of irrigation. Due to the variability of these parameters, obtaining consistent results and understanding the ablation effect in tissue can be challenging using current systems and methods for ablation. Consequently, current ablation systems may be limited due to difficulties and challenges in pre- and post-ablation tissue analysis and imaging. [Overview of the Initiative] [Means for solving the problem]

[0009] (summary) The present invention recognizes the limitations of current tissue analysis and visualization using ultrasound technology, namely, the inability to image and analyze the transmurality and continuity of ablation pathways.

[0010] In particular, the present invention provides a system and method for real-time contrast-enhanced ultrasound imaging of an anatomical region of interest that provides improved tissue imaging by utilizing data related to changes in microvessels. More specifically, the present invention facilitates the detection and visualization of the full range of ablation performed on an anatomical structure by utilizing three-dimensional (3D) and / or four-dimensional (4D) ultrasound images of an anatomical structure of interest, in contrast to 2D ultrasound imaging, and leveraging the associated changes in microvessel characteristics, specifically, by utilizing changes in ultrasound data related to tissue perfusion, to indicate / detect and visualize ablation foci.

[0011] For example, the system and method of the present invention may generally receive ultrasound image data (i.e., 3D and / or 4D images) from an imaging device such as a US imaging machine. The ultrasound image data is generally associated with an anatomical region of interest, including a targeted tissue site such as a specific site to be ablated (i.e., cardiac tissue or equivalent). The ultrasound image data is further associated with the perfusion of contrast agent to the targeted tissue site before, during, and / or after the ablation procedure is performed thereon. Depending on the analysis of the perfusion of contrast agent to the blood vessels associated with the targeted tissue site, multiple images from the ultrasound image data are dynamically reconstructed to provide a 3D visualization of the anatomical region of interest and the targeted tissue site, including, in particular, the visualization of ablation lesion formation in the targeted tissue site.

[0012] Analysis of contrast agent perfusion involves identifying perfusion characteristics in the microvessels of the targeted tissue site, and a given ablation lesion is identified based on such perfusion characteristics. For example, unhindered propagation and accumulation of contrast agent in a given location of microvessels may generally indicate unaffected and otherwise healthy microvessels, while a lack of propagation and accumulation of contrast agent in a given location indicates damaged microvessels. Therefore, the system and method of the present invention can effectively identify and characterize ablation lesions based at least in part on the correlation between perfusion characteristics and physical characteristics of a given location of microvessels. Consequently, visualization of a given ablation lesion may include the extent of the ablation lesion, the transmural nature of the ablation lesion, and the continuity of the ablation pathway associated with the ablation lesion.

[0013] Therefore, the present invention provides, in particular, improved analysis of ablated lesions for catheter-induced ablation procedures. Current imaging techniques lack the ability to measure the extent, transmurality, and continuity of the ablation pathway induced by the ablation catheter during an ablation procedure. Each of these attributes correlates with the success of long-term isolation in the treatment of cardiac arrhythmias. The present invention recognizes that tissue perfusion can be used in the identification and / or detection of ablated areas. Accordingly, the present invention makes it possible to utilize tissue perfusion, i.e., real-time contrast-enhanced ultrasound imaging, to identify microvascular changes in the tissue of interest and provide visual evidence of the extent of the ablated lesion identified during and after surgery, thereby enabling improved ablation pathway planning and execution, and improved patient outcomes.

[0014] An aspect of the present invention includes a system for providing tissue analysis and visualization, comprising an imaging device and a console operably associated therewith. In particular, the imaging device comprises a console comprising a hardware processor coupled to non-transient computer-readable memory containing instructions, the instructions being executable by the processor to cause the console to receive three-dimensional (3D) ultrasound image data from the imaging device and to dynamically reconstruct multiple images from the 3D image data. The 3D image data is associated with an anatomical region of interest, including a target tissue site, and the perfusion of contrast agent to the target tissue site before, during, and / or after an ablation procedure is performed on the tissue. The dynamically reconstructed images provide 3D visualization of the anatomical region of interest and the target tissue site, at least in part, based on an analysis of the perfusion of contrast agent to blood vessels associated with at least the target tissue site.

[0015] In some embodiments of this system, the 3D ultrasound image data is real-time 3D ultrasound data. In some embodiments, 3D visualization includes visualization of ablation lesion formation in the targeted tissue site.

[0016] In certain embodiments, the tissue includes microvessels associated with the targeted tissue site. For example, the analysis may include identifying perfusion characteristics in the microvessels. Furthermore, in some embodiments, ablation focus formation is identified based on the perfusion characteristics. In some embodiments of the system, the console is configured to correlate the perfusion characteristics of microvessels within a given location with the physical characteristics of the microvessels at that location. In specific embodiments, the perfusion characteristics include a series of gradual transitions of contrast agent propagation and accumulation within the microvessels at a given location.

[0017] For example, in some embodiments, the unhindered propagation and accumulation of contrast agent within a given location of a microvessel indicates an unaffected and otherwise healthy microvessel, while the absence of propagation and accumulation of contrast agent within a given location indicates a damaged microvessel. Specifically, in certain embodiments, a damaged microvessel is a result of ablation, and the absence of propagation and accumulation of contrast agent within a given location indicates part of the ablation lesion formation. Therefore, in some embodiments of the system, the console is configured to characterize the ablation lesion formation, at least in part, based on a correlation between the perfusion characteristics and physical characteristics of a given location of a microvessel.

[0018] These physical properties may, in some embodiments, be one or more of flowability, microflowability, and rigidity. In specific embodiments of the system of the present invention, characterization includes providing a visual indication of at least one of the extent of cauterization cavity formation, the transmurality of cauterization cavity formation, and the continuity of the ablation pathway associated with cauterization cavity formation.

[0019] Furthermore, in some embodiments of the system, the console is configured to segment a given ablation lesion into at least three distinct regions, comprising a core region, a boundary region directly adjacent to and surrounding the core region, and a peripheral region directly adjacent to and surrounding the boundary region. For example, in certain embodiments, the core region of the ablation lesion is associated with a complete or near-complete absence of contrast agent propagation and accumulation in a given location of microvessels and appears normal in the 3D ultrasound image. The boundary region of the ablation lesion is associated with some degree of contrast agent propagation and accumulation in a given location of microvessels and presents a stronger backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the core region. Furthermore, the peripheral region of the ablation lesion is, in some embodiments, associated with a substantially unhindered absence of contrast agent propagation and accumulation in a given location of microvessels and presents a weaker backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the boundary region in a short time after injection.

[0020] In some embodiments of the system of the present invention, the console performs segmentation of a given cauterization lesion formation based at least in part on a segmentation algorithm. For example, in a specific embodiment, the segmentation algorithm comprises at least one of automatic thresholding, connected component analysis, and neural network-based segmentation.

[0021] In some embodiments, a contrast agent may be injected into the blood vessel before and / or after performing one or more ablation procedures. Specifically, in some embodiments, the system of the present invention further comprises a catheter-based ultrasound imaging device operably coupled to a console, the catheter-based ultrasound imaging device configured to transmit ultrasound pulses into intravascular and / or intracardiac tissue and then receive echoes of the ultrasound pulses.

[0022] For example, in some embodiments, the ultrasound imaging device may comprise a four-dimensional (4D) catheter-based ultrasound imaging device. Thus, the console may be configured to receive at least 3D circumferential image data from the ultrasound imaging device in real or near real time, and the console may be configured to reconstruct multiple images in real or near real time, at least in part, based on user input and / or a predefined protocol. In specific embodiments, the console may be configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during an ablation procedure being performed on the targeted tissue site.

[0023] In a specific embodiment of the system of the present invention, the anatomical region of interest and the targeted tissue site are associated with myocardial tissue.

[0024] In a further aspect, the present invention discloses a method for providing ablation lesion analysis and visualization. In some embodiments, the method includes providing a console configured to be operably coupled to, communicate with, and exchange data with an imaging device; receiving three-dimensional (3D) ultrasound image data from the imaging device via the console; and dynamically reconstructing multiple images from the 3D image data via the console to provide 3D visualization of an anatomical region of interest and a targeted tissue site. The 3D image data is associated with an anatomical region of interest including a targeted tissue site and with the perfusion of contrast agent to the targeted tissue site before, during, and / or after an ablation procedure is performed on the targeted tissue site. The 3D visualization comprises visualization of any detected ablation lesion formation at the targeted tissue site, at least in part, based on an analysis of the perfusion of contrast agent to blood vessels associated with at least the targeted tissue site.

[0025] In some embodiments of this method, the 3D ultrasound image data is real-time 3D ultrasound data. In some embodiments, 3D visualization includes visualization of ablation lesion formation in the targeted tissue site.

[0026] In certain embodiments of the method, the tissue includes microvasculature associated with the targeted tissue site. For example, the analysis may include identifying perfusion characteristics in the microvasculature. Further, ablation foci formation is, in some embodiments, identified based on perfusion characteristics.

[0027] In some embodiments of the method, the console is configured to correlate perfusion characteristics within a given location of the microvasculature with the physical characteristics of the microvasculature at that given location. In a specific embodiment, the perfusion characteristics include a plurality of gradual transitions of the propagation and accumulation of a contrast agent into a given location of the microvasculature.

[0028] For example, in some embodiments of the method, unimpeded propagation and accumulation of a contrast agent into a given location of the microvasculature indicates a microvasculature that is otherwise healthy and unaffected, and the absence of propagation and accumulation of a contrast agent into a given location indicates a damaged microvasculature. Specifically, the damaged microvasculature is, in certain embodiments, the result of ablation, and the absence of propagation and accumulation of a contrast agent into a given location indicates a part of ablation foci formation. Thus, in some embodiments of the method, the console is configured to characterize ablation foci formation, at least in part, based on the correlation between the perfusion characteristics and the physical characteristics of a given location of the microvasculature.

[0029] These physical characteristics may be one or more of flow, microflow, and stiffness in some embodiments of the method. In a specific embodiment of the method of the present invention, the characterization includes providing at least one visual indication of the extent of ablation foci formation, the transmurality of ablation foci formation, and the continuity of the ablation path associated with ablation foci formation.

[0030] Furthermore, in some embodiments of the present method, the console is configured to segment a given ablation lesion into at least three distinct regions, comprising a core region, a boundary region directly adjacent to and surrounding the core region, and a peripheral region directly adjacent to and surrounding the boundary region. For example, in certain embodiments, the core region of the ablation lesion is associated with a complete or near-complete absence of contrast agent propagation and accumulation in a given location of microvessels and appears normal in the 3D ultrasound image. The boundary region of the ablation lesion is associated with some degree of contrast agent propagation and accumulation in a given location of microvessels and presents a stronger backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the core region. Furthermore, in some embodiments, the peripheral region of the ablation lesion is associated with a substantially unhindered absence of contrast agent propagation and accumulation in a given location of microvessels and presents a weaker backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the boundary region in a short time after injection.

[0031] In some embodiments of the method of the present invention, the console performs segmentation of a given cauterization lesion based at least in part on a segmentation algorithm. Specifically, in some embodiments, the segmentation algorithm comprises at least one of automated thresholding, connected component analysis, and neural network-based segmentation.

[0032] In a specific representation of this method, the contrast agent may be injected into the blood vessel before and / or after performing one or more ablation procedures. For example, in some embodiments, the system of the present invention further comprises a catheter-based ultrasound imaging device operably coupled to a console, which is configured to transmit ultrasound pulses into intravascular and / or intracardiac tissue and to receive echoes of the ultrasound pulses therefrom. Specifically, in some embodiments, the ultrasound imaging device may comprise a four-dimensional (4D) catheter-based ultrasound imaging device. Thus, the console may be configured to receive at least 3D circumferential image data from the ultrasound imaging device in real or near real time, and the console may be configured to reconstruct multiple images in real or near real time, at least in part, based on user input and / or a predefined protocol. In specific embodiments, the console may be configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during the ablation procedure being performed on the targeted tissue site.

[0033] In specific embodiments of the method of the present invention, the anatomical region of interest and the targeted tissue site are associated with myocardial tissue.

[0034] In another aspect, the present invention provides a method for contrast-enhanced imaging, comprising the steps of injecting a contrast agent, receiving 3D image data, dynamically reconstructing the image data, providing 3D visualization of an anatomical region of interest, and monitoring the perfusion of the contrast agent. In some embodiments, the contrast agent is injected directly into the heart. In other embodiments, the contrast agent is injected indirectly through a vein or artery. In some embodiments, the injection of the contrast agent may occur one or more times, for example, when it relates to imaging an anatomical region of interest and / or to suit the needs of the procedure being performed. The perfusion of the contrast agent is monitored via ultrasound imaging. In some embodiments, monitoring may include monitoring the flushing, perfusion, and / or dispersion of the contrast agent.

[0035] Furthermore, in some embodiments, monitoring via ultrasound imaging may be performed at any point, for example, during contrast agent injection, before and / or during the procedure, and during post-procedure follow-up. In some embodiments, monitoring may include displaying changes in contrast agent perfusion. In some embodiments, reconstruction may include reconstructing multiple images from 3D data to provide 3D visualization of anatomical regions of interest and targeted tissue sites. Thus, in some embodiments, reconstruction may include algorithmically relating changes in contrast agent perfusion to tissue properties.

[0036] In another aspect, the present invention provides a method for contrast-enhanced imaging, comprising the steps of injecting a contrast agent, receiving 3D image data, segmenting an anatomical region of interest, displaying a visualization of changes in contrast agent perfusion, and relating changes in contrast agent perfusion to tissue properties. [Brief explanation of the drawing]

[0037] [Figure 1]Figures 1A and 1B are schematic illustrations of an exemplary ultrasound system for providing visualization and characterization of blood vessels within a patient, which may be used in combination with the device of the present invention.

[0038] [Figure 2] Figure 2 is a perspective view of an imaging catheter to which the device of the present invention may be attached.

[0039] [Figure 3] Figure 3 illustrates an embodiment of the system of the present invention in which the console actively communicates with a computing system that includes algorithms for assessing, visualizing, and / or evaluating targeted tissue sites.

[0040] [Figure 4] Figure 4 is a block diagram of a method for providing cauterization lesion analysis and visualization according to one embodiment of the present invention.

[0041] [Figure 5] Figure 5 is a block diagram of a method for contrast-enhanced imaging according to one embodiment of the present invention.

[0042] [Figure 6] Figure 6 is a block diagram of a method for contrast-enhanced imaging according to one embodiment of the present invention. [Modes for carrying out the invention]

[0043] (Detailed explanation) This invention recognizes the limitations of current tissue analysis and visualization using ultrasound technology, namely the inability to image and analyze the transmurality and continuity of ablation pathways. In particular, this invention provides a novel system and method for real-time contrast-enhanced ultrasound imaging of an anatomical region of interest. Specifically, changes in the characteristics of ultrasound data related to changes in blood vessels or microvessels are utilized to provide improved tissue imaging. In certain embodiments, this invention provides a novel system and method for imaging ablative lesions, however, it should be understood that the system and method of this invention generally provides improved tissue imaging.

[0044] For example, the novel systems and methods of the present invention provide the measurement of the extent, transmurality, and continuity of the ablation pathway induced by the ablation catheter during an ablation procedure, which is not currently possible with modern systems. Each of these attributes correlates with the success of long-term isolation in the treatment of cardiac arrhythmias. Thus, the present invention provides real-time visual information regarding the extent of the ablation lesion, thereby enabling better ablation lesion pathway planning and execution, and improved patient outcomes.

[0045] The present invention provides a system and method for visualizing tissue quality through changes in perfusion in the tissue being evaluated, using an ultrasound contrast agent. In a specific embodiment, the present invention discloses the visualization of the ablation area through changes in perfusion to tissue such as myocardial tissue before, during, and / or after an ablation procedure.

[0046] Aspects of the present invention disclose a system for providing tissue analysis and visualization. The system may include a console with a hardware processor coupled to non-transient computer-readable memory containing instructions executable by the processor. Instructions may cause the console to receive three-dimensional (3D) ultrasound image data from an imaging device and to dynamically reconstruct multiple images from the 3D image data to provide 3D visualization of anatomical regions of interest and targeted tissue sites. The 3D image data may be associated with anatomical regions of interest, including targeted tissue sites. Targeted tissue sites may have associated levels of perfusion when applied, for example, before, during, and / or after an ablation procedure is performed on the tissue. The reconstructed images may be at least partially based on an analysis of the level of contrast agent perfusion to blood vessels associated with at least the targeted tissue sites.

[0047] (Ultrasound imaging system) In general, as is commonly understood, ultrasound imaging (echocardiography) uses high-frequency sound waves to visualize the inside of the body. Because ultrasound images are captured in real time, these images can also show the movement of internal organs as well as fluid flow (e.g., blood flowing through blood vessels). In ultrasound imaging, the imaging device (i.e., transducer, probe, or transducer probe) is placed directly on the skin or inside a body opening (e.g., intravascular ultrasound, intravascular sonication, intracardiac echocardiography). The final quality of the image acquired through ultrasound scanning is limited by the technical specifications of the equipment, the propagation of ultrasound through the tissue being analyzed, and the method used to reconstruct the image.

[0048] The system of the present invention may be operably connected to an ultrasound system, including certain hardware and software for providing image reconstruction and imaging assembly control, as described, for example, in Hennersperger et al.'s International PCT Application No. PCT / IB2019 / 000963 (published as WO2020 / 044117), Hennersperger et al.'s U.S. Application Publication No. US2022-0287679A1, and Hennersperger et al.'s U.S. Patent No. 11,382,599 (the contents of which are incorporated herein by reference). The data may be processed using imaging protocols for extracting anatomical and functional information and tissue characteristics, as disclosed in Hennersperger et al.'s International PCT Application No. PCT / IB2019 / 000963 (published as No. WO2020 / 044117), Hennersperger et al.'s U.S. Application Publication No. US2022-0287679A1, and Hennersperger et al.'s U.S. Patent No. 11,382,599 (the contents of which are incorporated herein by reference).

[0049] The system of the present invention is configured to receive three-dimensional (3D) ultrasound image data from an imaging device. In some embodiments, the present invention provides three-dimensional visualization and tissue characterization for use in minimally invasive intravascular procedures. Therefore, ultrafast ultrasound imaging techniques such as plane wave or divergent wave imaging may be required to enable imaging, particularly within the constraints of applications for intravascular and / or intracardiac tissue assessment and analysis. These constraints may be imposed due to high time update rates required for the effects observed in visualization and tissue characterization, and planar and divergent wave methods, generally also referred to as ultrafast imaging approaches, enable high imaging rates. The system and method of the present invention enable the direct use of all inherent ultrafast imaging techniques.

[0050] For example, in the context of intracardiac imaging, plane wave imaging may refer to an ultrasound imaging modality in which a plane wavefront can traverse tissue and be partially scattered back to the transducer through the flat transmission of all transducer elements (at different angles) from an angular imaging aperture. From the received radio frequency (RF) (i.e., channel) data, the overall image can be reconstructed simultaneously and in parallel by dynamically beamforming the RF data received for each target location.

[0051] Ultrafast ultrasound methods result in imaging at thousands of frames per second, limited only by the physical propagation speed of sound waves within tissue, enabling ultra-high-sensitivity blood flow tracking, shear wave imaging, super-resolution imaging, and other applications. For example, achieving optimal spatial resolution while enabling artifact-free imaging of dynamic cardiac structures requires a careful balance between spatial sampling and volume update rate, which can only be achieved using ultrafast imaging techniques. Therefore, the 3D ultrasound image data received by the system of the present invention may be real-time 3D ultrasound data. For example, the data may be 3D image data. Specifically, 3D visualization may be visualization of ablation lesion formation in the targeted tissue site.

[0052] The system of the present invention may include a catheter-based ultrasound imaging device operably coupled to a console, which is configured to transmit ultrasound pulses into intravascular and / or intracardiac tissue and to receive echoes of the ultrasound pulses.

[0053] Figures 1A and 1B are schematic illustrations of an exemplary system 100 for providing visualization and characterization of tissues and / or blood vessels / microvessels within a patient 12. The system 100 may include an imaging device 101 equipped with an imaging assembly 104 and a console 106 to which the imaging device 101 should be connected. The imaging device may also be an imaging catheter 102. Thus, the systems and methods for tissue analysis / assessment disclosed herein may use a 4D intracardiac echocardiography (ICE) system to capture an anatomical structure of interest. ICE is a catheter-based form of echocardiography that collects images from within the heart, rather than by collecting images of the heart by transmitting sound waves through the chest wall. In specific embodiments of the system, the ultrasound imaging device comprises a four-dimensional (4D) catheter-based ultrasound imaging device.

[0054] Figure 2 is a perspective view of an imaging catheter 102, which may be coupled with the system of the present invention. The catheter 102 may include a catheter body 108, which includes proximal and distal portions. An imaging assembly 104 may be provided, for example, in the distal portion, defining the distal end of the imaging catheter. A handle 110 is operably associated with the catheter body 108, allowing an operator (i.e., a surgeon or other medical professional) to manipulate and advance the imaging assembly 104 and the catheter body 108 to a desired target site in the patient's blood vessel. The handle 110 may include user-operable inputs for controlling various features and functions of the imaging assembly 104. An interface member 112 may be provided in the distal portion of the catheter body 108. The interface member 112 generally provides a connection between the imaging catheter 102, including the imaging assembly 104 and the handle 110, and a console 106 for the transmission of signals between them. The connection may include, for example, at least one of wired and wireless connections.

[0055] In one embodiment of this system, the console is configured to receive at least 3D circumferential image data from an ultrasound imaging device in real or near real time. Thus, the console is configured, at least partially, to reconstruct multiple images in real or near real time based on user input and / or a predefined protocol. As described in more detail herein, in some embodiments, the console is configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during an ablation procedure being performed on the targeted tissue site.

[0056] The console may be operably coupled to the imaging device and may generally control the operation of the transducer probe, i.e., the transmission of sound waves from the probe. The console may generally include one or more processors (e.g., a central processing unit (CPU), a graphics processing unit (GPU), or both) and a storage device such as main memory, static memory, or a combination of both, which communicate with each other via a bus or equivalent. The memory according to embodiments of the present invention may include a machine-readable medium on which one or more sets of instructions (e.g., software) embodying one or more of the methodologies or functions described herein are stored. The software may also reside in the main memory and / or processor, all or at least partially, during its execution by the computer system, and the main memory and processor also constitute the machine-readable medium. The software may further be transmitted or received over a network and via a network interface device.

[0057] Figure 3 illustrates one embodiment of the system 100 of the present invention. For example, in an exemplary embodiment, the system 100 may include a console 200 that actively communicates with a computing system 203 configured to communicate across a network. The computing system 203 or computing device may include one or more processors and memory, as well as input / output mechanisms (i.e., a keyboard, knobs, scroll wheels, or equivalent), which an operator can use to operate the machine, including performing other tasks described herein, such as adjusting the transmission characteristics of the probe, saving images, and selecting specific areas of interest for subsequent reconstruction into 2D and / or 3D images.

[0058] During operation, the CPU and / or GPU may control the transmission and reception of current, subsequently resulting in the emission and reception of sound waves from the probe. The CPU and / or GPU may also analyze the electrical pulses generated by the probe in response to the reflected waves returning, and then convert this data into an image (i.e., an ultrasound image), which can then be viewed on a display, which may be an integrated monitor. Such an image may also be stored in memory and / or printed via a printer. The console may further provide control over the imaging assembly, including control over the emission of ultrasound pulses therefrom (intensity, frequency, duration, etc.) and control over the movement of the ultrasound transducer unit.

[0059] The computing system 203 may include a computer program comprising an algorithm 204 for assessing and analyzing target tissue sites. For example, the algorithm 204 may be part of a computer program that is executable by the computing system 203 and communicates with the console of system 100. The system may communicate with the imaging device 101 and receive 3D ultrasound image data from the imaging device 101.

[0060] Imaging protocols and algorithms may be used to reconstruct the properties of the targeted tissue site. As will be discussed in more detail herein, the system may include one or more algorithms for dynamically reconstructing multiple images from 3D image data to provide 3D visualization of anatomical regions of interest and targeted tissue sites. For example, using a defined algorithm, the system may be configured to generate 3D visualization at least in part based on an analysis of contrast agent perfusion to blood vessels and / or microvessels associated with at least the targeted tissue site.

[0061] The evaluation of vascular / microvascular and tissue characteristics using the system of the present invention may include both an anatomical description of the vascular / microvascular system and information about the pathway and depth of the ablation lesion during cardiac interventions such as ablation. Specifically, data related to perfusion characteristics may be used and analyzed for visualization of anatomical regions of interest. Tissue reconstruction may also be performed by capturing data related to perfusion, rigidity, strain, anisotropy, coherence, specific statistical distribution within the tissue (Rayleigh, Nakagami), spectral parameters of the tissue (frequency power spectrum), and extraction of other parameters. This data may be captured using a rotating three-dimensional multi-element ultrasound transducer array. The data may be captured at a single point in time or at different stages, for example, before, during, or after the ablation procedure.

[0062] Tissue state mapping or functional imaging may be performed by integrating tissue data with appropriate imaging protocols and reconstruction algorithms, as described above. These individual protocols and algorithms may be integrated to evaluate and extract information from the data regarding, for example, rigidity, microvascularity, elasticity, perfusion, flow, shear wave velocity, and other information indicating tissue state.

[0063] (Tissue assessment using perfusion characteristics) As described above, the system of the present invention dynamically reconstructs multiple images from 3D image data to provide 3D visualization of anatomical regions of interest and targeted tissue sites. The 3D visualization provides means for assessing and analyzing anatomical regions of interest and targeted tissue sites. The assessment is at least in part based on the analysis of contrast agent perfusion to blood vessels or microvessels associated with at least the targeted tissue site. Specifically, the present invention provides automated ablation lesion segmentation using 3D / 4D data acquisition of anatomical structures of interest, thereby facilitating the detection and visualization of the entire range of ablation lesions in anatomical structures.

[0064] Conventional approaches to imaging ablated lesions have largely failed to characterize changes in ultrasound data related to changes in tissue properties such as rigidity and echogenicity. This invention discloses a novel approach to imaging tissue scarring and / or necrosis by utilizing changes in the characteristics of microvessels. Specifically, the system and method of the present invention use tissue perfusion imaging to indicate and / or detect areas of scarring and / or necrosis.

[0065] As disclosed, the 3D ultrasound image data may be real-time 3D ultrasound data, and the 3D visualization may include visualization of ablation lesion formation in the targeted tissue site. Accordingly, the tissue assessment system and method of the present invention may use a 4D ICE system that captures the anatomical structure of interest using ultrasound imaging. Specifically, an ultrasound contrast agent is used to visualize the targeted tissue site through changes in tissue perfusion.

[0066] Ultrasonographic contrast agents consist of small echogenic bubbles the size of red blood cells, as described in Greis, 2011, “Quantitative evaluation of microvascular blood flow by contrast-enhanced ultrasound (CEUS),” Clinical hemorheology and microcirculation 49.1-4:137-149 (which is incorporated herein in whole). Generally, ultrasonographic contrast agents consist of tiny gas-filled microbubbles the size of red blood cells. As is known to those skilled in the art, due to their size distribution, they are pure intravascular tracers that do not leach into the interstitial fluid and can therefore be used to image blood distribution and flow. Thus, contrast agents can effectively propagate into both larger blood vessels and microvascular vessels. More generally, contrast agents can propagate into any blood vessel in which red blood cells may be present.

[0067] Ultrasound contrast agents, for example, dramatically increase backscatter signals and, when sound pressure is applied, modify the reflection pattern by resonating in a linear manner. Increasing the sound pressure reveals nonlinear vibration patterns. Specifically, microbubbles, when compressed by the positive pressure effect generated by ultrasound, oscillate and expand in the negative pressure phase. The compression of the gas outweighs the expansion, generating a nonlinear response (echo). This greatly affects ultrasound backscattering and increases vascular contrast.

[0068] This invention leverages these properties to provide a novel system and method for detecting areas of scarring or necrosis in tissue using tissue perfusion, for example, blood flow in an anatomically important area. Specifically, an ultrasound contrast agent is used to visualize tissue properties through changes in tissue perfusion. Differences in perfusion within microvessels are utilized for novel tissue analysis and visualization.

[0069] As disclosed herein, the present invention provides a system for receiving three-dimensional (3D) ultrasound image data from an imaging device. The console may be configured to receive at least 3D circumferential image data from the ultrasound imaging device in real or near real time. Furthermore, the console may be configured to reconstruct multiple images in real or near real time, at least in part, based on user input and / or a predefined protocol.

[0070] This system provides dynamic reconstruction of multiple images from 3D image data to provide 3D visualization of anatomical regions of interest and targeted tissue sites. The 3D image data may be associated with the perfusion of contrast agent within the anatomical regions of interest and targeted tissue sites, including the targeted tissue sites. Therefore, in some embodiments, the 3D visualization includes visualization of ablation lesion formation in the targeted tissue. For example, the tissue may be microvessels associated with the targeted tissue site.

[0071] The console may be configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during the ablation procedure being performed on the targeted tissue site. While specific embodiments of the system of the present invention relate to the analysis and assessment of ablated areas of myocardium, it is important to note that the targeted tissue may be any tissue in which the perfusion properties of the contrast agent can be evaluated. As described in detail herein, the distribution and / or absence of microvascular perfusion may be assessed as markers for tissue, including, but not limited to, imaging of the ablated area.

[0072] Specifically, following the propagation of contrast agent microbubbles in the tissue, the area of ​​scarring and / or necrosis, i.e., the ablation lesion, referred to as the core, will not contain a significant amount of contrast agent (microbubbles) and will appear normal on the ultrasound image. A second area adjacent to the core, referred to as the boundary region, will be characterized by some thermal damage and rupture in microvessels where the contrast agent accumulates within the tissue, and therefore may generate a stronger backscatter signal on the ultrasound image. The system of the present invention captures changes in contrast agent perfusion and algorithmically relates these changes to tissue properties. Thus, in some embodiments, the analysis includes identifying perfusion characteristics in microvessels.

[0073] In specific embodiments, the system algorithmically segments the ablated lesion into different segments, for example, three or more segments. The segments may be, for example, a core, a boundary region, and a periphery. The core may be demarcated from the boundary region, which appears brighter, and from the unaffected healthy area around the ablated lesion. Reconstructed images of these three regions may be identified using the system of the present invention, for example, using a 3D / 4D ultrasound system combined with a contrast agent. Thus, the contrast agent in intact blood vessels disappears rapidly, while particles exiting through ruptured blood vessels remain long enough for imaging.

[0074] Segmentation may be performed by vision algorithms such as thresholding, connected component analysis, and neural network-based segmentation.

[0075] The ablated area may be visualized in real time. For example, a contrast agent may be injected when the catheter is positioned to visualize the anatomical structure of interest. Thus, the anatomical structure of interest may be visualized while the contrast agent is injected. Therefore, it is conceivable to create a 3D anatomical map showing the tissue before and after the ablation procedure. This allows for a comparative view. In this application, ultrasound data may be gated using electrocardiogram (ECG) signals, and the 3D map may be calculated before and after ablation of the anatomical structure of interest.

[0076] Regarding the injection of contrast agents into the bloodstream, direct injection of contrast agents into the heart or coronary arteries may be performed. Direct injection into the coronary arteries allows for the rapid and efficient distribution of specific contrast agents into the myocardium. Alternatively, the contrast agent may be introduced into the left atrium. This allows for the propagation of contrast agents from the left atrium (LA) (enabling propagation from the LA to the left ventricle (LV), into the aorta, and from the aorta into the myocardium), directly into the aorta, or from other anatomical sites that facilitate the transition of microbubbles into the myocardium, as described in Greis, 2011, "Quantitative evaluation of microvascular blood flow by contrast-enhanced ultrasound (CEUS)," Clinical hemorheology and microcirculation 49.1-4 (2011): 137-149 (incorporated herein by reference).

[0077] Analysis of the reconstructed images may also be based at least in part on an analysis of contrast agent perfusion to blood vessels and / or microvessels associated with at least the targeted tissue site. For example, the analysis may include identifying perfusion characteristics in microvessels so that ablation focus formation is identified based on perfusion characteristics.

[0078] In some embodiments, the console is configured to correlate the perfusion characteristics of microvessels within a given location with the physical characteristics of the microvessels at that location. In non-limiting embodiments, the characteristics analyzed may also include physical characteristics of both the contrast agent and the tissue of interest, such as flow, microflow, and rigidity. In some embodiments, the distribution and structure of microvessels are also used as tissue markers.

[0079] For example, perfusion characteristics may include multiple gradual transitions of contrast agent propagation and accumulation within a given location of microvessels. Therefore, unhindered propagation and accumulation of contrast agent within a given location of microvessels may indicate unaffected and otherwise healthy microvessels. Similarly, the absence of propagation and accumulation of contrast agent within a given location indicates damaged microvessels. Damaged microvessels may be, for example, the result of ablation. Therefore, the absence of propagation and accumulation of contrast agent within a given location may indicate a portion of ablation lesion formation. Thus, the console may be configured to characterize ablation lesion formation, at least in part, based on a correlation between perfusion characteristics and physical characteristics of a given location of microvessels.

[0080] As disclosed herein, in non-limiting embodiments, the physical properties may be one or more of flowability, microflowability, and rigidity. Furthermore, the characterization may include providing a visual indication of at least one of the extent of cauterization cavity formation, the transmurality of cauterization cavity formation, and the continuity of the ablation pathway associated with cauterization cavity formation.

[0081] As disclosed herein, the console may be configured to segment a given ablation lesion into at least three distinct regions, comprising a core region, a boundary region directly adjacent to and surrounding the core region, and a peripheral region directly adjacent to and surrounding the boundary region. The core region of the ablation lesion may be associated with a complete or near-complete absence of contrast agent propagation and accumulation in a given location of microvessels and may appear normal in the 3D ultrasound image. The boundary region of the ablation lesion may be associated with some degree of contrast agent propagation and accumulation in a given location of microvessels and presents a stronger backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the core region. The peripheral region of the ablation lesion may be associated with a substantially unhindered absence of contrast agent propagation and accumulation in a given location of microvessels and presents a weaker backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the boundary region in a short time after injection.

[0082] The segmentation performed by the console of a given cauterization lesion formation may be based, at least in part, on a segmentation algorithm. The segmentation algorithm may include at least one of automated thresholding, connected component analysis, and neural networks.

[0083] As disclosed herein, the tissue assessment systems and methods of the present invention may be used in conjunction with a 4D ICE system to capture anatomical structures of interest using ultrasound imaging. In specific embodiments, the present invention provides a system for imaging, assessing, and analyzing ablated areas, using blood flow in myocardial microvessels to indicate and detect ablated regions. The anatomical regions of interest and targeted tissue sites may therefore be associated with myocardial tissue. Thus, the extent of ablated areas before, during, and / or after the ablation procedure may be analyzed based on rupture / perfusion within the microvessels.

[0084] As described, the system and method described are general and applicable in the treatment of vascular problems, but are particularly useful in the treatment of atrial fibrillation (AF) and other heart diseases, as well as in endovascular procedures. AF is an irregular heartbeat caused by electrical signals originating from the atrioventricular ventricles of the heart, which disrupt the regular rhythm of the beating heart. AF is treated by isolating the origin of these electrical signals and limiting their transmission by ablation of the cells that surround the origin and conduct the electrical impulses. The system and method of the present invention may be used for general ablation foci monitoring and / or tissue assessment and analysis in ventricular tachycardia and renal artery denervation, etc.

[0085] In specific embodiments, the system uses the perfusion of a contrast agent to indicate and / or detect the ablated area. Taking advantage of the properties of ultrasound contrast agents, a contrast agent for ultrasound imaging, such as SonoVue, is injected into the coronary artery before, during, and / or after performing one or more ablations.

[0086] Cardiac ablation uses energy to create a cauterized lesion, i.e., a scar, blocking irregular electrical signals and restoring a typical heartbeat. Ablation performed as part of cardiac ablation causes alterations to the microvessels within the myocardium, resulting in an area of ​​myocardium that is no longer properly perfused and therefore not supplied with blood, e.g., the ablation core. These differences in blood flow within the microvessels of the myocardium are utilized for cauterized lesion detection and visualized from reconstructed 3D image data. The reconstructed images may also be analyzed, at least in part, from the level of contrast agent perfusion to vessels and / or microvessels associated with at least the targeted tissue site. Thus, the present invention provides real-time visual evidence of the extent of the cauterized lesion during surgery, thereby enabling improved cauterized lesion route planning and execution, and improved patient outcomes.

[0087] Following the propagation of contrast agent microbubbles in the myocardium, the ablation core will not contain a significant amount of contrast agent (microbubbles) and will appear normal on the ultrasound image. A second area adjacent to the ablation core, referred to as the boundary region, is characterized by some thermal damage and rupture in microvessels where contrast agent accumulates within the tissue, and therefore may generate a stronger backscatter signal on the ultrasound image.

[0088] The system of the present invention may capture changes before, during, and after catheter ablation. For example, the system may include a catheter-based ultrasound imaging device operably coupled to a console, which is configured to transmit ultrasound pulses into intravascular and / or intracardiac tissue and then receive echoes of the ultrasound pulses.

[0089] The ultrasound imaging device may be a four-dimensional (4D) catheter-based ultrasound imaging device. The console may be configured to receive at least 3D circumferential image data from the ultrasound imaging device in real or near real time. Furthermore, the console may be configured to reconstruct multiple images in real or near real time, at least in part, based on user input and / or a predefined protocol.

[0090] In some embodiments, the console is configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during the ablation procedure being performed on the targeted tissue site.

[0091] As described above, the system may algorithmically segment the ablation lesion into, for example, three or more segments. The segments may be, for example, an ablation core, a boundary region, and a periphery. The ablation core may be delineated from the boundary region, which appears brighter, and from the unaffected healthy area around the ablation lesion. Reconstructed images of these three regions may be identified using the system of the present invention, for example, using a 3D / 4D ultrasound system combined with a contrast agent, in combination with tissue edema as an immediate response to RF ablation.

[0092] Regarding the injection of contrast agents into the bloodstream, it should be understood that injection into the coronary arteries will allow for the rapid and efficient distribution of specific contrast agents into the myocardium. Alternatively, the contrast agent may also be introduced into the left atrium (allowing propagation from the LA to the LV, into the aorta, and from the aorta into the myocardium), directly into the aorta, or into other anatomical sites that facilitate the transition of microbubbles into the myocardium. In specific embodiments, the contrast agent may be injected into the blood vessels before and / or after performing one or more ablation procedures.

[0093] (Method for providing analysis and visualization of cauterized lesions) One aspect of the present invention discloses a method for providing analysis and visualization of cauterized lesions.

[0094] Figure 4 illustrates one embodiment of a method 400 for providing ablation lesion analysis and visualization. The method includes providing a console 401 which is operably coupled to an imaging device and configured to communicate with the imaging device and exchange data. Furthermore, the method includes receiving three-dimensional (3D) ultrasound image data from the imaging device via the console 403. The 3D image data is associated with an anatomical region of focus including a target tissue site and the perfusion of contrast agent to the target tissue site before, during, and / or after an ablation procedure is performed on the anatomical region of focus. The method includes dynamically reconstructing multiple images from the 3D image data via the console 405 and providing 3D visualization of the anatomical region of focus and the target tissue site 407. The 3D visualization includes visualization of any detected ablation lesion formation at the target tissue site, at least in part, based on an analysis of the perfusion of contrast agent to blood vessels and / or microvessels associated with at least the target tissue site.

[0095] The system used in the method of the present invention is configured to receive three-dimensional (3D) ultrasound image data from an imaging device.

[0096] In some embodiments, the present invention provides three-dimensional visualization and tissue characterization for use in minimally invasive intravascular procedures. For example, the tissue may be microvascular vessels associated with a targeted tissue site. Therefore, ultrafast ultrasound imaging techniques, such as plane wave or divergent wave imaging, may be required, in particular, to enable imaging within the constraints of applications for intravascular and / or intracardiac tissue assessment and analysis. The systems and methods of the present invention enable the direct use of all intrinsic ultrafast imaging techniques.

[0097] For example, in the context of intracardiac imaging, plane wave imaging may refer to an ultrasound imaging modality in which a plane wavefront can traverse tissue and be partially scattered back to the transducer through the flat transmission of all transducer elements (at different angles) from an angular imaging aperture. From the received radio frequency (RF) (i.e., channel) data, the overall image can be reconstructed simultaneously and in parallel by dynamically beamforming the RF data received for each target location.

[0098] Ultrafast ultrasound methods result in imaging at thousands of frames per second, limited only by the physical propagation speed of sound waves within tissue, enabling ultra-high-sensitivity blood flow tracking, shear wave imaging, super-resolution imaging, and other applications. For example, achieving optimal spatial resolution while enabling artifact-free imaging of dynamic cardiac structures requires a careful balance between spatial sampling and volume update rate, which can only be achieved using ultrafast imaging techniques. Therefore, the 3D ultrasound image data received by the system of the present invention may be real-time 3D ultrasound data. For example, the data may be 3D image data. Specifically, 3D visualization may be visualization of ablation lesion formation in the targeted tissue site.

[0099] As disclosed herein, the method of the present invention may include a catheter-based ultrasound imaging device operably coupled to a console, the catheter-based ultrasound imaging device configured to transmit ultrasound pulses into intravascular and / or intracardiac tissue and thereafter receive echoes of the ultrasound pulses.

[0100] In one embodiment of this method, the console is configured to receive at least circumferential 3D image data from an ultrasound imaging device in real or near real time. Thus, the console is configured to reconstruct multiple images in real or near real time, at least in part, based on user input and / or a predefined protocol. The console is configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during the ablation procedure being performed on the targeted tissue site.

[0101] The console may be operably coupled to the imaging device and may generally control the operation of the transducer probe, i.e., the transmission of sound waves from the probe. The console may generally include one or more processors (e.g., a central processing unit (CPU), a graphics processing unit (GPU), or both) and a storage device such as main memory, static memory, or a combination of both, which communicate with each other via a bus or equivalent. The memory according to embodiments of the present invention may include a machine-readable medium on which one or more sets of instructions (e.g., software) embodying one or more of the methodologies or functions described herein are stored. The software may also reside in the main memory and / or processor, all or at least partially, during its execution by the computer system, and the main memory and processor also constitute the machine-readable medium. The software may further be transmitted or received over a network and via a network interface device.

[0102] The method of the present invention may include a console that actively communicates with a computing system configured to communicate across a network. The computing system or computing device may include one or more processors and memory, as well as input / output mechanisms (i.e., a keyboard, knobs, scroll wheel, or equivalent), which an operator can interact with to operate the machine, including performing other tasks described herein, including adjusting the transmission characteristics of the probe, saving images, and selecting specific areas of interest for subsequent reconstruction into 2D and / or 3D images. During operation, the CPU and / or GPU may control the transmission and reception of current, subsequently resulting in the emission and reception of sound waves from the probe. The CPU and / or GPU may also analyze electrical pulses generated by the probe in response to the reflected waves returning, and then convert this data into an image (i.e., an ultrasonic image), which can then be viewed on a display, which may be an integrated monitor. Such images may also be stored in memory and / or printed via a printer. The console may further provide control over the imaging assembly, including control over the emission of ultrasonic pulses therefrom (intensity, frequency, duration, etc.) and control over the movement of the ultrasonic transducer unit.

[0103] The computing system may include a computer program that comprises algorithms for assessing and analyzing target tissue sites. For example, the algorithm may be part of a computer program that is executable by the computing system and communicates with the system's console. The system may communicate with an imaging device and receive 3D ultrasound image data from the imaging device.

[0104] The imaging protocol and algorithms may be used to reconstruct the properties of the targeted tissue site. The method may include one or more algorithms for dynamically reconstructing multiple images from 3D image data to provide 3D visualization of the anatomical region of interest and the targeted tissue site. For example, using a defined algorithm, the system of the method may be configured to generate 3D visualization at least in part based on an analysis of contrast agent perfusion to blood vessels and / or microvessels associated with at least the targeted tissue site.

[0105] The evaluation of vascular / microvascular, perfusion characteristics, and tissue characteristics using this method may include both an anatomical description of the vascular / microvascular, as well as information about the pathway and depth of the ablation lesion during cardiac interventions such as ablation. Specifically, data related to perfusion characteristics may be used and analyzed for visualization of anatomical regions of interest. The method of the present invention provides analysis of perfusion characteristics within a given location of microvasculars and identification of any ablation lesion formation based on the perfusion characteristics. Furthermore, the perfusion characteristics may include multiple gradual transitions of contrast agent propagation and accumulation within a given location of microvasculars. As disclosed herein, unhindered propagation and accumulation of contrast agent within a given location of microvasculars may indicate unaffected and otherwise healthy microvasculars. The absence of propagation and accumulation of contrast agent within a given location may indicate damaged microvasculars as a result of ablation, and thereby indicate part of the ablation lesion formation.

[0106] The characterization of ablation lesion formation may, at least in part, be based on the correlation between the perfusion and physical properties of a given location of microvessels. Therefore, tissue reconstruction may also be performed by capturing data related to perfusion, rigidity, strain, anisotropy, coherence, specific statistical distribution within the tissue (Rayleigh, Nakagami), spectral parameters of the tissue (frequency power spectrum), and the extraction of other parameters. This data can be captured using a rotating three-dimensional multi-element ultrasound transducer array. The data may be captured at a single point in time or at different stages, for example, before, during, or after the ablation procedure.

[0107] The method of the present invention may also use tissue state mapping or functional imaging, which is carried out by integrating tissue data with appropriate imaging protocols and reconstruction algorithms, as described above. These individual protocols and algorithms may be integrated to evaluate and extract information from the data regarding, for example, rigidity, microvascularity, elasticity, perfusion, flow, shear wave velocity, and other information indicating tissue state.

[0108] The method of the present invention dynamically reconstructs multiple images from 3D image data to provide 3D visualization of anatomical regions of interest and targeted tissue sites. The 3D visualization provides means for assessing and analyzing anatomical regions of interest and targeted tissue sites. The assessment is at least in part based on the analysis of contrast agent perfusion to blood vessels or microvessels associated with at least the targeted tissue site. In specific embodiments, the method of the present invention provides automated ablation lesion segmentation using 3D / 4D data acquisition of anatomical structures of interest, thereby facilitating the detection and visualization of the entire extent of ablation lesions in anatomical structures.

[0109] As disclosed herein, conventional approaches to imaging ablation sites have largely failed to characterize changes in ultrasound data related to changes in tissue properties such as rigidity and echogenicity. The present invention discloses a novel method for imaging tissue scarring and / or necrosis by utilizing changes in the characteristics of microvessels. Specifically, the method uses tissue perfusion imaging to indicate and / or detect areas of scarring and / or necrosis.

[0110] As disclosed, the 3D ultrasound image data may be real-time 3D ultrasound data, and the 3D visualization may include visualization of ablation lesion formation in the targeted tissue site. Accordingly, the tissue assessment system and method of the present invention may use a 4D ICE system that captures the anatomical structure of interest using ultrasound imaging. Specifically, an ultrasound contrast agent may be used to visualize the targeted tissue site through changes in tissue perfusion.

[0111] Ultrasonographic contrast agents consist of small echogenic bubbles the size of red blood cells, as described in Greis, 2011, “Quantitative evaluation of microvascular blood flow by contrast-enhanced ultrasound (CEUS),” Clinical hemorheology and microcirculation 49.1-4:137-149 (which is incorporated herein in whole). Generally, ultrasonographic contrast agents consist of tiny gas-filled microbubbles the size of red blood cells. As is known to those skilled in the art, due to their size distribution, they are pure intravascular tracers that can be used to image blood distribution and flow. Thus, contrast agents can effectively propagate into both larger blood vessels and microvascular vessels. More generally, contrast agents can propagate into any blood vessel in which red blood cells may be present.

[0112] Ultrasound contrast agents, for example, dramatically increase backscatter signals and, when sound pressure is applied, modify the reflection pattern by resonating in a linear manner. Increasing the sound pressure reveals nonlinear vibration patterns. Specifically, microbubbles, when compressed by the positive pressure effect generated by ultrasound, oscillate and expand in the negative pressure phase. The compression of the gas outweighs the expansion, generating a nonlinear response (echo). This greatly affects ultrasound backscattering and increases vascular contrast.

[0113] This invention leverages these properties to provide a novel method for detecting areas of scarring or necrosis in tissue using tissue perfusion, for example, blood flow in an anatomically important area. Specifically, an ultrasound contrast agent is used to visualize tissue properties through changes in tissue perfusion. Differences in perfusion within microvessels are utilized for novel tissue analysis and visualization.

[0114] Figure 5 is a block diagram of a method 500 for contrast-enhanced imaging according to one embodiment of the present invention. Method 500 includes injecting a contrast agent 501, receiving 3D image data 503, dynamically reconstructing the image data 505, providing 3D visualization of an anatomical region of interest 507, and monitoring the perfusion of the contrast agent 509. As will be discussed in more detail herein, the contrast agent may be injected directly into the heart or indirectly through an artery or vein. The injection of the contrast agent may occur one or more times, for example, when it relates to imaging of an anatomical region of interest and / or to suit the needs of the procedure being performed. The contrast agent is monitored via ultrasound imaging. Monitoring may include monitoring the flushing, perfusion, and / or dispersion of the contrast agent. Monitoring via ultrasound imaging may be performed at any time, for example, at the time of contrast agent injection, before and / or during the procedure, and in post-procedure follow-up. Monitoring may include displaying changes in contrast agent perfusion. Reconstruction may include reconstructing multiple images from 3D data to provide 3D visualizations of anatomical regions of interest and targeted tissue sites. Therefore, reconstruction may include algorithmically relating changes in contrast agent perfusion to tissue properties.

[0115] In some embodiments, the method includes analysis of reconstructed images. For example, the analysis of reconstructed images may be at least in part an analysis of the perfusion of contrast agent to blood vessels or microvessels associated with at least the targeted tissue site. For example, the analysis may include identifying perfusion characteristics in microvessels so that ablation focus formation is identified based on perfusion characteristics.

[0116] The ablated area may be visualized in real time. For example, a contrast agent may be injected when the catheter is positioned to visualize the anatomical structure of interest. Thus, the anatomical structure of interest may be visualized while the contrast agent is injected. Therefore, it is possible to create a 3D anatomical map showing the tissue before and after the procedure, such as the ablation procedure, in order to enable a comparative view. In this application, ultrasound data may be gated using electrocardiogram (ECG) signals, and the 3D map may be calculated before and after ablation of the anatomical structure of interest.

[0117] As disclosed herein, the present invention provides a system for receiving three-dimensional (3D) ultrasound image data from an imaging device. The console may be configured to receive at least 3D circumferential image data from the ultrasound imaging device in real or near real time. Furthermore, the console may be configured to reconstruct multiple images in real or near real time, at least in part, based on user input and / or a predefined protocol.

[0118] This system provides dynamic reconstruction of multiple images from 3D image data in order to offer 3D visualization of anatomical regions of interest and targeted tissue sites.

[0119] Figure 6 is a block diagram of a method 600 for contrast-enhanced imaging according to one embodiment of the present invention. As will be described in more detail below, the method may generally include injecting a contrast agent 601, receiving 3D image data 603, segmenting a region of interest 605, displaying a visualization of changes in contrast agent perfusion 607, and relating changes in contrast agent perfusion to tissue properties 609.

[0120] As described herein, 3D image data may generally include circumferential 3D image data, specifically 3D volumetric data, captured by an imaging device during an ultrasound procedure. The 3D image data may be associated with an anatomical region of interest, including the targeted tissue site, and with the perfusion of contrast agent within the targeted tissue site. Thus, in some embodiments, 3D visualization includes visualization of ablation lesion formation in the targeted tissue. For example, the tissue may be microvessels associated with the targeted tissue site.

[0121] In specific embodiments, the method may algorithmically segment an anatomical area of ​​interest, such as a cauterized lesion, into, for example, three or more segments. The segments may include, for example, a core, a boundary region, and a periphery. The core can be demarcated from the brighter-looking boundary region and the unaffected, healthy area surrounding the cauterized lesion. Reconstructed images of these three regions are identified using the system of the present invention, for example, using a 3D / 4D ultrasound system combined with a contrast agent. Segmentation may be performed by vision algorithms such as thresholding, connected component analysis, or neural network-based segmentation. Contrast agents in intact blood vessels disappear rapidly, but particles exiting through ruptured blood vessels remain long enough for imaging.

[0122] The console may be configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during the ablation procedure being performed on the targeted tissue site. While specific embodiments of the system of the present invention relate to the analysis and assessment of ablated areas of myocardium, it is important to note that the targeted tissue may be any tissue in which the perfusion properties of the contrast agent can be evaluated. As described in detail herein, the distribution and / or absence of microvascular perfusion may be assessed as markers for tissue, including, but not limited to, imaging of the ablated area.

[0123] Specifically, following the propagation of contrast agent microbubbles in the tissue, the area of ​​scarring and / or necrosis, i.e., the ablation lesion, referred to as the core, will not contain a significant amount of contrast agent (microbubbles) and will appear normal on the ultrasound image. A second area adjacent to the core, referred to as the boundary region, will be characterized by some thermal damage and rupture in microvessels where the contrast agent accumulates within the tissue, and therefore may generate a stronger backscatter signal on the ultrasound image. The system of the present invention captures changes in contrast agent perfusion and algorithmically relates these changes to tissue properties. Thus, in some embodiments, the analysis includes identifying perfusion characteristics in microvessels.

[0124] In specific embodiments, the method may algorithmically segment the ablated lesion into, for example, three or more segments. The segments may include, for example, a core, a boundary region, and a periphery. The core may be demarcated from the boundary region, which appears brighter, and from the unaffected healthy area around the ablated lesion. Reconstructed images of these three regions are identified using the system of the present invention, for example, using a 3D / 4D ultrasound system combined with a contrast agent. Segmentation may be performed by vision algorithms such as thresholding, connected component analysis, or neural network-based segmentation. Contrast agents in intact blood vessels disappear rapidly, but particles exiting through ruptured blood vessels remain long enough for imaging.

[0125] The ablated area may be visualized in real time. For example, a contrast agent may be injected when the catheter is positioned to visualize the anatomical structure of interest. Thus, the anatomical structure of interest may be visualized while the contrast agent is injected. Therefore, it is conceivable to create a 3D anatomical map showing the tissue before and after the ablation procedure. This allows for a comparative view. In this application, ultrasound data may be gated using electrocardiogram (ECG) signals, and the 3D map may be calculated before and after ablation of the anatomical structure of interest.

[0126] Regarding the injection of contrast agents into the bloodstream, direct injection of contrast agents into the heart or coronary arteries may be performed. Direct injection into the coronary arteries allows for the rapid and efficient distribution of specific contrast agents into the myocardium. Alternatively, the contrast agent may be introduced into the left atrium. This allows for the propagation of contrast agents from the left atrium (LA) (enabling propagation from the LA to the left ventricle (LV), into the aorta, and from the aorta into the myocardium), directly into the aorta, or from other anatomical sites that facilitate the transition of microbubbles into the myocardium, as described in Greis, 2011, "Quantitative evaluation of microvascular blood flow by contrast-enhanced ultrasound (CEUS)," Clinical hemorheology and microcirculation 49.1-4 (2011): 137-149 (incorporated herein by reference).

[0127] Analysis of the reconstructed images is based at least in part on an analysis of contrast agent perfusion to blood vessels or microvessels associated with at least the targeted tissue site. For example, the analysis may include identifying perfusion characteristics in microvessels so that ablation focus formation is identified based on perfusion characteristics.

[0128] In some embodiments, the console is configured to correlate the perfusion characteristics of microvessels within a given location with the physical characteristics of the microvessels at that location. In non-limiting embodiments, the characteristics analyzed may also include physical characteristics of both the contrast agent and the tissue of interest, such as flow, microflow, and rigidity. In some embodiments, the distribution and structure of microvessels are also used as tissue markers.

[0129] For example, perfusion characteristics may include multiple gradual transitions of contrast agent propagation and accumulation within a given location of microvessels. Thus, unhindered propagation and accumulation of contrast agent within a given location of microvessels indicates unaffected and otherwise healthy microvessels. Similarly, the absence of propagation and accumulation of contrast agent within a given location indicates damaged microvessels. Damaged microvessels may, for example, be the result of ablation. Thus, the absence of propagation and accumulation of contrast agent within a given location may indicate a portion of ablation lesion formation. Therefore, the console may be configured to characterize ablation lesion formation, at least in part, based on a correlation between perfusion characteristics and physical characteristics of a given location of microvessels. In non-limiting embodiments as disclosed herein, the physical characteristics may be one or more of flow, microflow, and rigidity. Furthermore, the characterization may include providing a visual indication of at least one of the following: the extent of ablation lesion formation, the transmural nature of ablation lesion formation, and the continuity of the ablation pathway associated with ablation lesion formation.

[0130] The console may be configured to segment a given ablation lesion into at least three distinct regions, comprising a core region, a boundary region directly adjacent to and surrounding the core region, and a peripheral region directly adjacent to and surrounding the boundary region. The core region of the ablation lesion may be associated with a complete or near-complete absence of contrast agent propagation and accumulation in a given location of microvessels and may appear normal in the 3D ultrasound image. The boundary region of the ablation lesion may be associated with some degree of contrast agent propagation and accumulation in a given location of microvessels and presents a stronger backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the core region. The peripheral region of the ablation lesion may be associated with a substantially unhindered absence of contrast agent propagation and accumulation in a given location of microvessels and presents a weaker backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the boundary region in a short time after injection.

[0131] The segmentation performed by the console of a given cauterization lesion formation may be based, at least in part, on a segmentation algorithm. The segmentation algorithm may include at least one of automated thresholding, connected component analysis, and neural networks.

[0132] As disclosed herein, the tissue assessment method of the present invention may be used in conjunction with a 4D ICE system to capture anatomical structures of interest using ultrasound imaging. In specific embodiments, the present invention provides a system for imaging, assessing, and analyzing ablated areas, using blood flow in myocardial microvessels to indicate and detect the ablated area. The anatomical area of ​​interest and targeted tissue site may therefore be associated with myocardial tissue. Thus, the extent of ablated areas before, during, and / or after the ablation procedure may be analyzed based on rupture / perfusion within the microvessels.

[0133] As described herein, the method is general and applicable in the treatment of vascular problems, but it is particularly useful in the treatment of atrial fibrillation (AF) and other heart diseases, as well as in endovascular procedures. AF is an irregular heartbeat caused by electrical signals originating from the atrioventricular ventricles of the heart, which disrupt the regular rhythm of the beating heart. AF is treated by isolating the origin of these electrical signals and limiting their transmission by ablation of the cells that surround the origin and conduct the electrical impulses. The system and method of the present invention may be used for general ablation foci monitoring and / or tissue assessment and analysis in ventricular tachycardia and renal artery denervation, etc.

[0134] In specific embodiments, the method uses contrast agent perfusion to indicate and / or detect ablated areas. Taking advantage of the properties of ultrasound contrast agents, a contrast agent for ultrasound imaging, such as SonoVue, is injected into the coronary arteries before, during, and / or after performing one or more ablations. Cardiac ablation uses energy to create a cauterized lesion, i.e., a scar, blocking irregular electrical signals and restoring a typical heartbeat. Ablation performed as part of cardiac ablation causes alterations to the microvessels within the myocardium, resulting in an area of ​​myocardium that is no longer properly perfused and therefore not supplied with blood, e.g., an ablation core. These differences in blood flow within the microvessels of the myocardium are utilized for cauterized lesion detection and visualized from reconstructed 3D image data. The reconstructed images may also be at least partially based on an analysis of the level of contrast agent perfusion to the vessels and / or microvessels associated with at least the targeted tissue site. Therefore, the present invention provides real-time visual evidence of the extent of the ablation lesion during surgical procedures, thereby enabling improved ablation pathway planning and execution, and improved patient outcomes.

[0135] Following the propagation of contrast agent microbubbles in the myocardium, the ablation core will not contain a significant amount of contrast agent (microbubbles) and will appear normal on the ultrasound image. A second area adjacent to the ablation core, referred to as the boundary region, is characterized by some thermal damage and rupture in microvessels where contrast agent accumulates within the tissue, and therefore may generate a stronger backscatter signal on the ultrasound image.

[0136] The method of the present invention may capture changes before, during, and after catheter ablation. For example, the system may include a catheter-based ultrasound imaging device operably coupled to a console, which is configured to transmit ultrasound pulses into intravascular and / or intracardiac tissue and then receive echoes of the ultrasound pulses.

[0137] The ultrasound imaging device may be a four-dimensional (4D) catheter-based ultrasound imaging device. The console may be configured to receive at least 3D circumferential image data from the ultrasound imaging device in real or near real time. Furthermore, the console may be configured to reconstruct multiple images in real or near real time, at least in part, based on user input and / or a predefined protocol.

[0138] In some embodiments, the console is configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during the ablation procedure being performed on the targeted tissue site.

[0139] As described above, the system may algorithmically segment the ablation lesion into, for example, three or more segments. The segments may be, for example, an ablation core, a boundary region, and a periphery. The ablation core may be demarcated from the boundary region, which appears brighter, and from the unaffected healthy area around the ablation lesion. Reconstructed images of these three regions, combined with tissue edema as an immediate response to RF ablation, are identified using the system of the present invention, for example, using a 3D / 4D ultrasound system combined with a contrast agent.

[0140] Regarding the injection of contrast agents into the bloodstream, it should be understood that injection into the coronary arteries will allow for the rapid and efficient distribution of specific contrast agents into the myocardium. Alternatively, the contrast agent may also be introduced into the left atrium (allowing propagation from the LA to the LV, into the aorta, and from the aorta into the myocardium), directly into the aorta, or into other anatomical sites that facilitate the transition of microbubbles into the myocardium. In specific embodiments, the contrast agent may be injected into the blood vessels before and / or after performing one or more ablation procedures.

[0141] As used in any embodiment of this specification, the term “module” may mean software, firmware, and / or a circuit configured to perform any of the operations described herein. Software may be embodied as software packages, code, instructions, instruction sets, and / or data recorded on a non-transient computer-readable storage medium. Firmware may be embodied as code, instructions, or instruction sets, and / or data hardcoded (e.g., non-volatile) within a memory device. “Circuitry” may, as used in any embodiment of this specification, include, for example, a wired network, a programmable network such as a computer processor comprising one or more individual instruction processing cores, a state-machine network, and / or firmware that stores instructions executed by a programmable network, either alone or in any combination. Modules may be embodied as a network that forms part of a larger system, collectively or individually, such as an integrated circuit (IC), a system-on-a-chip (SoC), a desktop computer, a laptop computer, a tablet computer, a server, a smartphone, and the like.

[0142] Any of the operations described herein may be implemented in a system including one or more storage media having instructions for performing the method, which are executed individually or in combination by one or more processors stored thereon. Here, the processors may include, for example, a server CPU, a mobile device CPU, and / or other programmable circuits.

[0143] Furthermore, it is intended that the operations described herein may be distributed across multiple physical devices, such as processing structures, in more than one different physical locations. The storage medium may include any type of tangible medium, such as any type of disk, including hard disks, floppy disks, optical disks, compact disk read-only memory (CD-ROM), rewritable compact disks (CD-RW), and magneto-optical disks; semiconductor devices such as read-only memory (ROM), random access memory (RAM) such as dynamic and static RAM, erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), flash memory, solid-state disks (SSDs); magnetic or optical cards; or any type of medium suitable for storing electronic instructions. Other embodiments may be implemented as software modules executed by a programmable control device. The storage medium may be non-transient.

[0144] As described herein, various embodiments may be implemented using hardware elements, software elements, or any combination thereof. Examples of hardware elements may include processors, microprocessors, circuits, circuit elements (e.g., transistors, resistors, capacitors, inductors, etc.), integrated circuits, application-specific integrated circuits (ASICs), programmable logic devices (PLDs), digital signal processors (DSPs), field-programmable gate arrays (FPGAs), logic gates, registers, semiconductor devices, chips, microchips, chipsets, etc.

[0145] Throughout this specification, any reference to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in relation to an embodiment is included in at least one embodiment. Therefore, the expressions “in one embodiment” or “in an embodiment” in various places throughout this specification do not necessarily all refer to the same embodiment. Furthermore, certain features, structures, or characteristics may be combined in any preferred manner in one or more embodiments.

[0146] The term "non-transitory" is understood to exclude only the transient signals themselves from the scope of the claims, and not to waive rights to all standard computer-readable media other than the transient signals themselves. In other words, the terms "non-transitory computer-readable medium" and "non-transitory computer-readable storage medium" should be interpreted as excluding only those types of transient computer-readable media that were found to fall outside the scope of patentable subject matter under Section 101 of the U.S. Patent Act in the In Re Nuijten case.

[0147] The terms and expressions used herein are for illustrative purposes only, not limitation, and in using such terms and expressions, there is no intention to exclude any equivalents of the features (or parts thereof) shown and described, and it should be recognized that various modifications are possible within the scope of the claims. Therefore, the claims are intended to encompass all such equivalents.

[0148] (Integrated by reference) References and citations to other documents, such as patents, patent applications, patent publications, journals, books, articles, and web content, are made throughout this disclosure. All such documents are incorporated herein by reference to this specification for any purpose.

[0149] (Equal portions) Various modifications of the present invention and many further embodiments thereof will be apparent to those skilled in the art from the entirety of this document, including, in addition to those shown and described herein, references to scientific and patent documents cited herein. The subject matter of this specification contains important information, examples, and guidance that may be adapted to the practice of the present invention in its various embodiments and equivalents thereof.

Claims

1. A system for providing organizational analysis and visualization, wherein the system is A console comprising a hardware processor coupled to non-transient computer-readable memory containing instructions, The aforementioned command is sent to the console, The method involves receiving three-dimensional (3D) ultrasound image data from an imaging device, wherein the 3D image data is associated with an anatomical region of interest including the target tissue site, and with the perfusion of contrast agent to the target tissue site before, during, and / or after the ablation procedure is performed on the target tissue site. To provide 3D visualization of the anatomical region of interest and the targeted tissue site, multiple images are dynamically reconstructed from the 3D image data, based at least in part on an analysis of the perfusion of the contrast agent to blood vessels associated with the targeted tissue site. A system that is executable by the processor to perform the following actions.

2. The system according to claim 1, wherein the 3D ultrasound image data is real-time 3D ultrasound data.

3. The system according to claim 1, wherein the 3D visualization includes visualization of the formation of a cauterization lesion in the targeted tissue area.

4. The system according to claim 1, wherein the tissue comprises microvessels associated with the targeted tissue site.

5. The system according to claim 4, wherein the analysis includes identifying the perfusion characteristics in the microvessels.

6. The system according to claim 5, wherein cauterization foci are identified based on the perfusion characteristics.

7. The system according to claim 5, wherein the console is configured to correlate the perfusion characteristics of the microvessels in a given location with the physical characteristics of the microvessels in the given location.

8. The system according to claim 5, wherein the perfusion characteristics comprise a plurality of gradual transitions of the propagation and accumulation of contrast agent into a given location in a microvessel.

9. The unimpeded propagation and accumulation of contrast agent within a given location of microvessels indicates unaffected and otherwise healthy microvessels. The system according to claim 8, wherein the absence of propagation and accumulation of contrast agent within a given location indicates damaged microvessels.

10. The system according to claim 9, wherein the damaged microvessels are a result of ablation, and the lack of propagation and accumulation of contrast agent in the given location indicates part of the formation of a cauterized lesion.

11. The system according to claim 10, wherein the console is configured, at least in part, to characterize the formation of a cauterized lesion based on the correlation between the perfusion characteristics and physical characteristics of the microvessels at a given location.

12. The system according to claim 11, wherein the physical property is one or more of flow, microflow, and rigidity.

13. The system according to claim 11, wherein the characterization includes providing a visual indication of at least one of the extent of the cauterization cavity formation, the transmurality of the cauterization cavity formation, and the continuity of the ablation pathway associated with the cauterization cavity formation.

14. The system according to claim 11, wherein the console is configured to segment a given cauterized cavity formation into at least three distinct regions, each comprising a core region, a boundary region directly adjacent to and surrounding the core region, and a peripheral region directly adjacent to and surrounding the boundary region.

15. The system according to claim 14, wherein the core region of the cauterized lesion formation is associated with the complete or near-complete absence of contrast agent propagation and accumulation in a given location of the microvessels and appears normal in a 3D ultrasound image.

16. The system according to claim 14, wherein the boundary region of the cauterized lesion formation is associated with some degree of propagation and accumulation of contrast agent into the given location of the microvessels, and presents a stronger backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the core region.

17. The system according to claim 14, wherein the peripheral region of the ablation lesion formation is associated with substantially unhindered propagation and lack of accumulation of contrast agent into a given location of microvessels, and shortly after injection, presents a weaker backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the boundary region.

18. The system according to claim 17, wherein the console performs segmentation of a given cauterization lesion formation based at least partially on a segmentation algorithm.

19. The system according to claim 18, wherein the segmentation algorithm comprises at least one of automatic thresholding, connected component analysis, and neural network-based segmentation.

20. The system according to claim 1, wherein the contrast agent is injected into the blood vessel before and / or after performing one or more ablation procedures.

21. The system according to claim 1, further comprising a catheter-based ultrasound imaging device operably coupled to the console, wherein the catheter-based ultrasound imaging device is configured to transmit ultrasound pulses into intravascular and / or intracardiac tissue and to receive echoes of the ultrasound pulses from intravascular and / or intracardiac tissue.

22. The system according to claim 21, wherein the ultrasound imaging device comprises a four-dimensional (4D) catheter-based ultrasound imaging device.

23. The system according to claim 21, wherein the console is configured to receive at least 3D circumferential image data from the ultrasound imaging device in real or near real time, and the console is configured to reconstruct a plurality of images in real or near real time, at least in part, based on user input and / or a predefined protocol.

24. The system according to claim 23, wherein the console is configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during an ablation procedure being performed on the targeted tissue site.

25. The system according to claim 1, wherein the anatomical region of interest and the targeted tissue site are associated with myocardial tissue.

26. A method for providing analysis and visualization of cauterized lesions, wherein the method is To provide a console configured to be operablely coupled to an imaging device, communicate with it, and exchange data with it, The process involves receiving three-dimensional (3D) ultrasound image data from the imaging device via the console, wherein the 3D image data is associated with an anatomical region of interest including the target tissue site, and with the perfusion of contrast agent to the target tissue site before, during, and / or after the ablation procedure is performed on the target tissue site. To provide a 3D visualization of the anatomical region of interest and the targeted tissue site via the console, a plurality of images are dynamically reconstructed from the 3D image data, wherein the 3D visualization comprises visualization of any detected ablation lesion formation in the targeted tissue site, at least in part, based on an analysis of contrast agent perfusion to blood vessels associated with at least the targeted tissue site. Methods that include...

27. The method according to claim 26, wherein the 3D ultrasound image data is real-time 3D ultrasound data.

28. The method according to claim 26, wherein the tissue comprises microvessels associated with the targeted tissue site.

29. The method according to claim 28, wherein the analysis includes identifying perfusion characteristics in the microvessels, and subsequently identifying arbitrary cauterization lesion formation based on the perfusion characteristics.

30. The method according to claim 29, further comprising correlating the perfusion characteristics of the microvessels at a given location with the physical characteristics of the microvessels at the given location via the console.

31. The method according to claim 30, wherein the perfusion characteristics comprise a plurality of gradual transitions of the propagation and accumulation of the contrast agent into a given location in the microvessels.

32. The unimpeded propagation and accumulation of contrast agent within a given location of microvessels indicates unaffected and otherwise healthy microvessels. The method according to claim 31, wherein the absence of propagation and accumulation of contrast agent within a given location indicates damaged microvessels as a result of ablation, thereby indicating a portion of the formation of a cauterized lesion.

33. The method according to claim 32, further comprising characterizing the formation of a cauterized lesion based at least in part on a correlation between the perfusion characteristics and physical characteristics of the microvessels at a given location.

34. The method according to claim 33, wherein the characterization includes providing a visual indication of at least one of the extent of the cauterization cavity formation, the transmurality of the cauterization cavity formation, and the continuity of the ablation pathway associated with the cauterization cavity formation.

35. The method according to claim 33, further comprising segmenting a given cauterized cavity formation into at least three distinct regions, each comprising a core region, a boundary region directly adjacent to and surrounding the core region, and a peripheral region directly adjacent to and surrounding the boundary region, via the console.

36. The method according to claim 35, wherein the core region of the cauterized lesion formation is associated with the complete or near-complete absence of the propagation and accumulation of contrast agent in a given location of the microvessels and appears normal in a 3D ultrasound image.

37. The method according to claim 35, wherein the boundary region of the cauterized lesion formation is associated with some degree of propagation and accumulation of contrast agent into the given location of the microvessels, and presents a stronger backscatter signal in the 3D ultrasound image compared to the backscatter signal associated with the core region and the peripheral region.

38. The method according to claim 35, wherein the peripheral region of the cauterization lesion is associated with substantially unhindered propagation and accumulation of contrast agent into a given location of microvessels, and the difference in backscatter signals in a 3D ultrasound image is presented compared to the backscatter signals associated with the boundary region.

39. The method according to claim 35, wherein the console performs segmentation of a given cauterization lesion formation based at least in part on a segmentation algorithm.

40. The method according to claim 39, wherein the segmentation algorithm comprises at least one of automatic thresholding, connected component analysis, and neural network-based segmentation.

41. The method according to claim 26, wherein the contrast agent is injected into a blood vessel before and / or after performing one or more ablation procedures.

42. The method according to claim 26, further comprising providing a catheter-based ultrasound imaging device operably coupled to the console, wherein the catheter-based ultrasound imaging device is configured to transmit ultrasound pulses into intravascular and / or intracardiac tissue and to receive echoes of the ultrasound pulses from intravascular and / or intracardiac tissue.

43. The method according to claim 42, wherein the ultrasound imaging device comprises a four-dimensional (4D) catheter-based ultrasound imaging device.

44. The method according to claim 42, wherein the console is configured to receive at least 3D circumferential image data from the ultrasound imaging device in real or near real time, and the console is configured to reconstruct a plurality of images in real or near real time, at least in part, based on user input and / or a predefined protocol.

45. The method according to claim 44, wherein the console is configured to provide 3D visualization of the anatomical region of interest and the targeted tissue site during an ablation procedure being performed on the targeted tissue site.

46. The method according to claim 26, wherein the anatomical region of interest and the targeted tissue site are associated with myocardial tissue.

Images