Systems and methods for imaging related to thermal ablation processing

Abstract

The ablation device includes a shaft and a radio frequency (RF) transmitter positioned in the shaft, the radio frequency (RF) transmitter delivering radio frequency (RF) energy to produce an ablation volume. The ablation device also includes an imaging sensor positioned within the tubular shaft, the imaging sensor configured to obtain imaging data of the ablation volume.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Patent Application No. 17 / 812,958, filed on July 15, 2022, which is incorporated herein by reference for all purposes as if fully set forth herein. Technical Field

[0003] The present disclosure relates to systems and methods for imaging associated with thermal ablation treatments. More specifically, the present disclosure relates to systems and methods that can use an ablation probe that performs both ablation and imaging functions. Background Art

[0004] Ablation is a procedure that uses extreme temperatures (heat) or microwaves or electrical currents to destroy (ablate) cancer cells and tumors. In some cases, such as when a patient is not a good candidate for tumor resection, thermal ablation may be considered as an alternative treatment method. Thermal ablation of cancerous tissue using radiofrequency (RF) or microwave (MW) energy is commonly used in the management of liver tumors and is becoming a real alternative for liver tumor resection.

[0005] RF and MW ablations are usually performed using one or more special needles or probes. The probe is inserted near or inside the target tissue (such as cancerous tissue), and the current sent through the probe heats the target tissue to a high temperature, which destroys the target tissue. The intention is that the treatment produces a limited or targeted heating zone so that the treatment generally does not affect surrounding healthy tissue and limits or minimizes damage to healthy tissue.

[0006] Ablation is usually preceded by a planning phase in which a medical professional (such as an interventional radiologist) predetermines the optimal probe path for the procedure. The procedure involves placing the ablation probe into the target tissue or tumor using computed tomography (CT) image guidance or other probe tracking and guidance techniques (such as a stereotactic camera). In general, planning and guidance can be performed by a medical professional.

[0007] There are various disadvantages to existing or conventional systems and methods. For example, once a medical professional begins ablation of a target tissue or tumor, there is no or limited real-time feedback about the actual volume of tissue being ablated. Anatomical factors can affect the ablation volume, and there is no simultaneous imaging technology that provides complete situational awareness during the procedure. For example, blood flow in nearby vessels can cool surrounding tissue and inhibit heating by thermal ablation. These factors lead to uncertainty about the actual ablation volume and exactly which tissue has been treated. Therefore, a reliable determination of the tumor ablation volume cannot be confirmed during the procedure. Typically, the first possibility to verify the ablation volume is provided by an imaging scan performed after the ablation procedure, in which the medical professional confirms the tumor status. Subsequent treatment may be required to re-ablate specific areas of the target tissue or tumor.

[0008] In addition, RF and MW ablations generate microbubbles in the ablation area due to the interaction of the high frequency current with the soft tissue. The microbubbles can interfere with imaging. These microbubbles appear as hyperechoic areas or clouds (areas that reflect many sound waves) with strong contrast in ultrasound images. The hyperechoic bubbles can affect ultrasound imaging outside of the microbubble cloud, resulting in a partial representation of the ablation volume when using existing equipment (such as handheld ultrasound probes). Therefore, there is a need for improved systems and methods for performing ablation treatments to allow for the collection of more information during treatment, such as imaging information describing the progress of the ablation treatment. Summary of the invention

[0009] In various embodiments of the present disclosure, systems and methods are provided that can obtain imaging information that describes the progress of an ablation treatment during a procedure. This information is an improvement over existing and conventional treatment methods by providing real-time feedback about the ablation of target tissue during treatment. This information can improve the effectiveness of the treatment and can reduce the likelihood of performing subsequent treatments. The systems and methods of the present disclosure allow medical professionals to determine whether all or a desired portion of the target tissue was destroyed during treatment. In addition, the systems and methods of the present disclosure can reduce and / or limit damage to healthy tissue that may be located near the target tissue.

[0010] In some embodiments of the present disclosure, systems and methods are provided that can achieve full imaging coverage (360°) of an ablation volume by placing multiple transducers around the ablation volume. In some examples, ultrasound imaging can be integrated into the ablation probe. In various examples, the ablation probe can facilitate full coverage of the ablation volume, which is not achievable with existing handheld or external imaging probes.

[0011] In some embodiments, the imaging sensor can be rotated to obtain imaging data from multiple directions, for example, the imaging sensor can be rotated about its axis within the probe to allow full coverage (e.g., 360°) of the ablation volume from the isocenter of the ablation volume and / or the center of the target tissue. In other examples, when the imaging sensor is configured as a phased array of imaging sensors positioned in the probe, rotation of the probe including an array (or multiple arrays) of imaging sensors can allow full coverage (e.g., 360°) of the ablation volume from the isocenter of the ablation volume and / or the center of the target tissue.

[0012] In addition, embodiments of the present disclosure can provide a miniaturized fiber-based design that eliminates interference between ultrasound and radio frequency / microwave (RF / MW) signals (decoupling imaging from therapy), facilitates optical tracking of ablation probes using computed tomography (CT) registration, and maps imaging overlays of shear wave elastography (SWE) and bubble clouds in one image for better tissue ablation assessment.

[0013] In some embodiments, the ablation device may include a shaft and may include a radio frequency (RF) transmitter positioned in the shaft, the radio frequency (RF) transmitter delivering radio frequency (RF) energy to produce an ablation volume. The ablation device may also include an imaging sensor positioned in the tubular shaft, the imaging sensor being configured to obtain imaging data of the ablation volume. The shaft of the ablation probe may be a needle adapted to be inserted into the target tissue.

[0014] In some embodiments, the probe may include more than one axis or conduit. One or more axes may be configured in various structures. For example, each of the first axis and the second axis may be a cylindrical structure or a tubular structure. In other examples, the first axis and the second axis may have a semicircular cross-sectional shape. In other examples, other shapes and structures may be used. In some examples, more than one axis may be joined together. Various appropriate joining methods and / or accessories may be used to join one or more axes together, for example, adhesives, riveting, welding or a joining process may be used to join one or more axes together. In yet other examples, the probe housing may be formed as a whole to have one or more axes. This structure enables the imaging sensor and the RF transmitter to be positioned on different axes. In this way, the imaging assembly and the RF assembly may be separated and / or insulated from each other.

[0015] In one aspect, the shaft includes a distal end that is positioned at or near the target tissue during an ablation procedure, and the RF transmitter is positioned closer to the distal end than the imaging sensor.

[0016] In another aspect, the RF transmitter comprises a microwave (MW) antenna.

[0017] In another aspect, the RF transmitter includes a radio frequency (RF) electrode.

[0018] In another aspect, an imaging sensor includes an ultrasound transducer.

[0019] In another aspect, an imaging sensor includes an all-optical ultrasound transducer.

[0020] In another aspect, the imaging sensor is separate from the axis.The imaging sensor may be a stereotactic imaging device.

[0021] In another aspect, the imaging sensor is configured to operate simultaneously with the RF transmitter during the ablation procedure. In another aspect, ablation and imaging are performed alternately.

[0022] In another aspect, the imaging sensor is a first imaging sensor, and the ablation device further comprises a second imaging sensor positioned in the shaft. The second imaging sensor may be positioned at any suitable location on the probe. Suitably, the second imaging sensor may be positioned at the distal end of the probe. Suitably, the first imaging sensor and the second imaging sensor are positioned on opposite sides of the target tissue.

[0023] In another aspect, the RF transmitter is positioned between the first imaging sensor and the second imaging sensor.

[0024] In another aspect, the imaging device is configured to operate in an imaging mode to collect imaging data and in a shear wave elastography (SWE) mode to collect elastography data from the ablation volume.

[0025] It is intended that any aspect of the ablation device of the present disclosure may be used in any combination with any other aspect or aspects of the ablation device.

[0026] In some embodiments, an ablation system is provided. The ablation system may include: a probe configured to deliver RF energy to a target tissue in a patient; and a first imaging sensor positioned to obtain first imaging data from a first direction relative to the target tissue. The ablation system may also include a second imaging sensor positioned to obtain second imaging data from a second direction relative to the target tissue. The first direction and the second direction are different, and when in use, the second imaging sensor may be located inside the patient. In some embodiments, the first imaging sensor may be separated from the probe and may be located on an outer surface of the patient's skin when in use. Suitably, the first imaging sensor and the second imaging sensor are positioned on opposite sides of the target tissue.

[0027] In one aspect, the second imaging sensor can be located in the probe. In some embodiments, the second imaging sensor can be rotatable to obtain imaging data from multiple directions, for example, the imaging sensor can be rotated about its axis within the probe. In other examples, where the imaging sensor is configured as a phased array of imaging sensors positioned in the probe, the probe can be rotatable when in use to form an array (or multiple arrays) of imaging. The combination of the first imaging sensor and the second imaging sensor can capture up to and including a full 360° view of the ablation volume to allow full coverage (e.g., 360°) of the ablation volume from the isocenter of the ablation volume and / or the center of the target tissue.

[0028] In another aspect, the second imaging sensor is configured to operate concurrently with operation of the probe.

[0029] In another aspect, both the first imaging sensor and the second imaging sensor are located in the probe.

[0030] In another aspect, the second imaging sensor is located in the probe and may include an all-optical ultrasound transducer.

[0031] In another aspect, the second imaging sensor includes a silicon photonics based ultrasound transducer.

[0032] On the other hand, the probe includes a marker located on a portion of the probe. The marker can be positioned at a predetermined position on the probe. Other tracking and imaging can be used to determine and / or track the position of the probe. For example, electromagnetic tracking can be used to determine the position of the probe. In yet another embodiment, other markers and / or imaging methods can be used to determine the position of the probe.

[0033] The ablation systems of the present disclosure may include one or more probes.

[0034] It is intended that any aspect of the ablation system of the present disclosure may be used in any combination with any other aspect or aspects of the ablation system.

[0035] In some embodiments, a method of performing radio frequency (RF) treatment is provided. The method may include: energizing an RF transmitter located at or near target tissue in a patient, and obtaining first imaging data from a first direction relative to the target tissue. The method may also include: obtaining second imaging data from a second direction relative to the target tissue, and combining the first imaging data and the second imaging data to create an image of the ablation volume.

[0036] In one aspect, the second direction corresponds to a direction from inside the patient.

[0037] In another aspect, the step of powering the RF transmitter is performed simultaneously with at least one of obtaining the first imaging data and obtaining the second imaging data.

[0038] In another aspect, the first direction and the second direction correspond to opposite sides of the target tissue.

[0039] In another aspect, the second imaging data is obtained from an all-optical ultrasound transducer.

[0040] It is intended that any aspect of the method of performing RF therapy of the present invention may be used in any combination with any other aspect or aspects of the method of performing RF therapy.

[0041] The above and other features, elements, characteristics, steps and advantages of the present invention will become more apparent from the following detailed description of preferred embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] The features and advantages of the present disclosure will be more fully disclosed or become apparent in the following detailed description of example embodiments. Figure 1 1 and 2, wherein like reference numerals refer to like parts, and wherein:

[0043] Figure 1 is a diagram illustrating an ablation system according to one embodiment of the present disclosure.

[0044] Figure 2 is a diagram illustrating another ablation system including a hybrid RF / MW probe according to another embodiment of the present disclosure.

[0045] Figure 3 is a diagram illustrating another ablation system including another hybrid RF / MW probe according to another embodiment of the present disclosure.

[0046] Figure 4 is a side view of an example ablation probe that may be used with one or more ablation systems of the present disclosure.

[0047] Figure 5 is a side view of another example ablation probe that may be used with one or more ablation systems of the present disclosure.

[0048] Figure 6 is a side view of another example ablation probe that may be used with one or more ablation systems of the present disclosure.

[0049] Figure 7 is a side view of another example ablation probe that may be used with one or more ablation systems of the present disclosure.

[0050] Figure 8is used in the alternative operating mode Figure 4 Side view of an example ablation probe.

[0051] Fig. 9 is an image showing an ablation probe and an elastography map with a superimposed bubble cloud that may be generated using one or more ablation systems of the present disclosure.

[0052] Fig.10 is a flow chart of an example method of performing an ablation treatment according to the present disclosure. DETAILED DESCRIPTION

[0053] The description of the preferred embodiments is intended to be read in conjunction with the accompanying drawings, which are considered part of the entire written description of these disclosures. Although the present disclosure is susceptible to various modifications and alternative forms, specific embodiments are shown by way of example in the accompanying drawings and will be described in detail herein. From the following detailed description of these exemplary embodiments in conjunction with the accompanying drawings, the objects and advantages of the claimed subject matter will become more apparent.

[0054] However, it should be understood that the present disclosure is not intended to be limited to the specific forms disclosed. On the contrary, the present disclosure covers all modifications, equivalents and alternatives that fall within the spirit and scope of these exemplary embodiments. The terms "coupled", "coupled", "operably coupled", "operably connected", etc. should be broadly understood to refer to connecting devices or components together mechanically, electrically, wired, wirelessly or otherwise, so that the connection allows the related devices or components to operate (e.g., communicate) with each other as expected by virtue of the relationship.

[0055] In the present disclosure, the singular forms "one", "an" and "the" include plural references, and references to a specific numerical value include at least the specific value unless the context clearly indicates otherwise. When a value is expressed as an approximation by using the antecedent "about", it should be understood that the specific value forms another embodiment. As used herein, "about X" (wherein X is a numerical value) preferably refers to ±10% of the listed value, including the end value. For example, the phrase "about 8" preferably refers to a value of 7.2 to 8.8, including 7.2 and 8.8. If present, all ranges are inclusive and combinable. For example, when the range "1 to 5" is narrated, the narrated range should be interpreted as including the range "1 to 4", "1 to 3", "1-2", "1-2 and 4-5", "1-3 and 5", "2-5", etc. In addition, when a list of alternatives is provided affirmatively, such a list can be interpreted as meaning that any alternative in the alternatives can be excluded, such as by negative limitations in the claims. For example, when reciting a range of "1 to 5", the scope of the recitation can be interpreted as including the case of negatively excluding any of 1, 2, 3, 4 or 5; thus, the recitation of "1 to 5" can be interpreted as "1 and 3-5, but not including 2", or simply understood as "wherein 2 is not included". It is intended that any component, element, attribute or step explicitly recited herein can be explicitly excluded from the claims, regardless of whether such component, element, attribute or step is listed as an alternative or whether they are recited separately.

[0056] The present disclosure relates to systems and methods for improving or increasing the imaging of target tissue during ablation procedures. Figure 1 , an example ablation system 2 is shown. The ablation system 2 may include an ablation probe 20, a first imaging sensor 40, and a second imaging sensor 70. The ablation system 2 may be used, for example, during an ablation treatment in which it is desired to destroy a target tissue 10. The target tissue 10 may be a tumor, a lesion, a cancer, or other abnormal tissue in a patient. During the treatment, the ablation probe 20 may be inserted into the patient's skin 50, wherein the distal end of the probe 20 is positioned at or near the target tissue 10. The probe 20 may be any suitable ablation probe, such as a radio frequency (RF) ablation probe or a microwave (MW) ablation probe, which may cause an area at or near the distal end of the probe 20 to be heated to a high temperature that destroys tissue. The high temperature of the ablation zone may cause a bubble cloud 30 to be generated. It is desirable to obtain images or other information about the position of the probe 20, the position and / or size of the bubble cloud 30, and / or the position of the heated ablation zone to determine whether the target tissue and the ablation zone overlap so as to destroy the target tissue during the treatment.

[0057] The first imaging sensor 40 and the second imaging sensor 70 can be used during processing to obtain imaging data, which can be used to generate images of the target tissue 10, the probe 20 and / or the bubble cloud 30. The first imaging sensor 40 and the second imaging sensor 70 can be various suitable sensors, transducers, etc. For example, the first imaging sensor 40 and the second imaging sensor 70 can be ultrasonic transducers. In various examples, the first imaging sensor 40 and the second imaging sensor 70 can be electronic ultrasonic transducers, all-optical ultrasonic transducers, piezoelectric transducers (PZT), capacitive micromechanical ultrasonic transducers (CMUT), silicon photonics-based ultrasonic transducers, or transducers based on piezoelectric polyvinylidene fluoride (PVDF). In other examples, other imaging sensors can be used.

[0058] In the example shown, the first imaging sensor 40 and the second imaging sensor are positioned on opposite sides of the target tissue 10. This arrangement allows a more complete image of the target tissue 10, the probe 20 and the bubble cloud 30 to be obtained, and allows information about their relative positions to be provided. During the ablation process, the second imaging sensor 70 can use intracavitary ultrasound sensing. Intracavitary ultrasound sensing involves inserting an ultrasound transducer or sensor located in a tube, catheter or hollow portion into a patient's body (such as a blood vessel, stomach or intestine). The inserted ultrasound transducer is used to generate imaging data from the body. In one example, the system 2 can use an intracavitary ultrasound sensor. In other examples (not shown), the system 2 can include multiple intracavitary ultrasound sensors.

[0059] In the example shown, the first sensor 40 can be positioned on the outer surface of the patient's skin 50, with the first imaging field 60 (represented by the dashed triangle) pointing to the target tissue 10. The first imaging sensor 40 can be a handheld or any other suitable transducer, as described previously. The second imaging sensor 70 can be located at a different location than the first imaging sensor 40 and can be positioned on the opposite side of the target tissue 10 from the first imaging sensor 40. The second imaging sensor 70 can be a second ultrasound transducer (e.g., intravascular or endoscopic), and can be an intracavitary ultrasound transducer, and is positioned to image the "back side" of the target tissue 10 (the "back side" is the opposite side of the target tissue 10 from the direction of the first ultrasound transducer). The combination of the first imaging sensor 40 and the second imaging sensor 70 can capture the ablation volume up to and including a full 360° view. The second imaging sensor 70 can have a second imaging field 80 (represented by the dashed triangle). The combination of the second imaging sensor 70 and the first imaging sensor 40 provides improved coverage of the bubble cloud 30 and a more accurate representation of damaged tissue during ablation compared to conventional procedures using only a single imaging sensor.

[0060] In other embodiments (not shown), the system 2 may include Figure 1 Variations of the structures and configurations shown in . For example, system 2 may include more than two imaging sensors. System 2 may include more than one intracavitary ultrasound sensor or other imaging sensor positioned within the patient. The system may also include more than one imaging sensor positioned on the patient's skin 50 or otherwise located outside the patient's body.

[0061] Reference now Figure 2 , another ablation system 4 is shown. In this example, the ablation system may include a first imaging sensor 40 and a hybrid probe 22. The first imaging sensor 40 may be similar to the first imaging sensor 40 described with respect to the ablation system 2 described above. The hybrid probe 22 may allow multiple functions to be performed during the ablation process, such as both ablation and imaging. For example, the hybrid probe 22 may include a radio frequency (RF) transmitter, such as one or more RF electrodes and / or a microwave (MW) antenna. The hybrid probe 22 may also include an imaging sensor 45, such as an ultrasonic transducer. Various ultrasonic transducers may be used, such as those described above with respect to the second imaging sensor 70.

[0062] like Figure 2 As shown in , the hybrid probe 22 can be positioned at or near the target tissue 10 in the patient. When the RF transmitter is powered on, the hybrid probe 22 can generate a bubble cloud 30 around the target tissue 10. Imaging data can be collected by a first imaging sensor 40 and a second imaging sensor 45. The first imaging sensor 40 can be located on the patient's skin 50 and collect imaging data using a first ultrasound field 60 (represented by a dashed triangle) directed at the target tissue 10. In this embodiment, the hybrid probe 22 can include a second imaging sensor 45 at or near the distal end of the probe 22, and the second imaging sensor 45 provides ultrasound detection of a second ultrasound field 90 of the ablation volume from the distal end of the probe 22. The distal end is the end of the probe 22, which can be inserted into the patient and is farthest from the end of the probe that can be connected to the energy generation and sensing electronics. The second imaging sensor 45 can be positioned at any suitable position on the probe 22.

[0063] Compared to conventional procedures using only a single imaging device (such as the first imaging sensor 40), the combination of data from both the first imaging sensor 40 and the second imaging sensor 45 provides greater imaging coverage of the bubble cloud 30 and provides a more accurate representation of the target tissue 10 and / or the ablation volume. The second imaging sensor 45 can be rotated to obtain imaging data from multiple directions of the distal end of the probe 22. The second imaging device 45 can be rotated about its axis within the needle 22. In other examples, the second imaging device 45 can be configured as a phased array of imaging sensors positioned in the probe 22. Rotation of the second imaging device 45 and / or the probe 22 (which includes an array (or multiple arrays) of imaging sensors) can allow complete coverage (e.g., 360°) of the ablation volume from the isocenter of the ablation volume and / or the center of the target tissue 10.

[0064] In an example probe 22 including a rotating imaging device, a second imaging device 45 may be mounted and / or otherwise positioned at the distal end of the probe 22 and connected to a drive motor at the proximal end of the probe 22. The drive motor may rotate the second imaging device within the probe 22 to obtain a 360° image. In other examples including a phased array, the second imaging device 45 may include a plurality of transducers positioned around the periphery or circumference of the second imaging device 45 in the probe 22. In some examples, 36 individual transducers may be positioned around the circumference of the second imaging device 45. In other examples, other numbers of transducers may be used. These transducers may be triggered individually to acquire a 360° image. Various examples may present different advantages. Phased array imaging devices may have fewer motion artifacts due to the fact that they do not move during imaging, and may provide faster imaging than rotating devices. In contrast, rotating devices may have higher resolution, but may also include non-uniform rotational distortion artifacts.

[0065] The ablation system 4 can provide both ablation and imaging functions. In some examples, it is not desirable to perform imaging and ablation simultaneously because the RF / MW radiation may interfere with nearby imaging sensors. In this case, ablation and imaging can be performed alternately, as discussed further below. In other examples, such as when the first imaging sensor or the second imaging sensor is configured as an all-optical ultrasound sensor, imaging and ablation functions can be performed simultaneously, given that there is no interference between the RF / MW energy and the all-optical ultrasound sensor operation.

[0066] During use of the ablation system 4, the second imaging sensor 45 can be located at the center of the ablation zone or in close proximity to it. This arrangement provides a variety of improvements over other arrangements in which the imaging sensor is positioned adjacent to or spaced apart from the ablation zone and / or target tissue 10. The positioning of the second imaging sensor 45 at the center of the ablation zone (permitted by its position in the probe 22) provides a reduced distance between the imaging sensor and the bubble cloud 30 compared to other arrangements. In addition, the positioning of the second imaging sensor 45 at the center of the ablation zone also results in improved imaging contrast compared to other arrangements. Further, the positioning of the second imaging sensor 45 at the center of the ablation zone improves imaging interference from tissue surrounding the ablation zone. The imaging data obtained is further improved compared to other arrangements because the ultrasound waves are minimally affected by surrounding structures (such as bone, dense tissue, and air), which typically obscure ultrasound imaging when other arrangements are used.

[0067] In some embodiments, the second imaging sensor 45 can be rigidly fixed to the probe 22. With this integration, the second imaging sensor 45 and the RF transmitter in the probe 22 are automatically physically aligned relative to each other, thereby allowing the ablation volume to be directly overlapped on the imaged ablation volume with minimal mismatch. The integration of the second imaging sensor 45 and the RF transmitter in the probe 22 does not require the second imaging sensor 45 to be individually positioned relative to the ablation volume. Because when the probe 22 is positioned at the target tissue 10, the ultrasound sensor 45 is simultaneously and automatically located in the immediate vicinity or center of the ablation volume, there is no need to have special requirements for the power and sensitivity of the second imaging sensor 45. The power, sensitivity and / or other operating parameters of the second imaging sensor 45 can be predetermined and easily configured. Therefore, the ablation system 4 and the hybrid probe 22 provide multiple improvements over existing systems and devices. For example, the hybrid probe 22 can allow for sensing / imaging and ablation at the same time. Integrating the imaging function into the probe 22 also allows cost-effective implementation and reduces the complexity of the ablation process. Further, due to the improved imaging data that can be collected, the ablation process can be performed more effectively. This may improve the likelihood that the target tissue 10 is ablated during a single treatment, and damage to surrounding and / or healthy tissue is minimized or reduced.

[0068] Reference now Figure 3, another example ablation system 6 is shown. In this example, the ablation system 6 may include a probe 24 and a stereotactic imaging device 100. In this example, the probe 24 may include an imaging sensor 47, which is positioned at or near the distal end of the probe 24. The probe 24 may be similar to the previously described probe 22, and include both an RF / MW transmitter and an imaging sensor to provide both ablation and imaging functions. In this example, the imaging sensor 47 may be configured as an all-optical ultrasound transducer that allows for simultaneous ablation and ultrasound imaging. An all-optical transducer uses pulsed or modulated light to generate ultrasound waves via the photoacoustic effect, and may be less sensitive to electromagnetic noise than a non-optical transducer that converts electrical energy into ultrasound energy.

[0069] During use of the ablation system 6, an RF transmitter at the distal end of the probe 24 can be positioned at the target tissue 10. The RF transmitter can be energized to create an ablation volume, and a bubble cloud 30 can be generated around the target tissue 10. As shown, the probe 24 can also include a marker 105 located on a portion of the probe 24. The marker 105 can be positioned at a predetermined location on the probe 24. A stereotactic imaging device 100 can be used to obtain imaging data that detects the location of the marker 105. The imaging data can be used in combination with imaging data collected prior to the ablation procedure to determine the location of the probe 24 relative to the target tissue 10. Optical tracking using the stereotactic imaging device 100 and the marker 105 of the probe 24 helps to align the imaging to the preoperative CT image. In this example ablation system 6, the ablation procedure may no longer require an additional ultrasound transducer or other imaging sensor as previously described (i.e., on the patient's skin 50 or inside the patient). The stereotactic imaging device 100 may be any suitable imaging device that allows the distal end of the probe 24 to be guided in three planes using coordinates provided by medical imaging in order to reach the target tissue 10 within the patient's body.

[0070] In other examples and embodiments, other tracking and imaging may be used to determine and / or track the position of probe 24. For example, electromagnetic tracking may be used to determine the position of probe 24. In still other examples, other marking and / or imaging methods may be used to determine the position of probe 24.

[0071] In the illustrated embodiment, the imaging sensor 47 of the probe 24 can be an internal all-optical ultrasound transceiver at the distal end, which allows ultrasound detection from the ultrasound field 95 of the ablation volume at the distal end of the probe 24. The probe 24 helps to achieve a fully integrated imaging and therapy solution in one device. In some examples, the imaging sensor 47 can rotate within the probe 24. In other examples, the imaging sensor 47 can be configured as an array of imaging sensors. The rotation of the imaging sensor 47 and / or the imaging sensor array can allow the ablation volume to be fully covered from the isocenter of the ablation area. A full 360° view can be obtained from the imaging sensor 47. With this arrangement, imaging and therapy can be performed simultaneously with one device without the need for additional ultrasound transducers. In other examples, as a supplement to the imaging sensor 47, additional imaging sensors similar to the imaging sensor 47 can be added or used. Such additional imaging sensors and transducers can also be tracked using the imaging device 100, and can provide additional information and images of the target tissue 10, the bubble cloud 30, the surrounding tissues and other body structures.

[0072] The ablation system 6 can provide simultaneous therapy and imaging. The all-optical ultrasound transducer can allow the RF transmitter and the imaging sensor to operate simultaneously. Due to electromagnetic interference, conventional piezoelectric transducers (PZT), capacitive micromachined ultrasound transducers (CMUT), and piezoelectric polyvinylidene fluoride (PVDF)-based sensors cannot provide data for visualizing the ablation area during therapy mode. Integrating the imaging sensor 47 as an all-optical ultrasound transducer and / or a silicon photonics-based ultrasound transducer in the probe 24 provides improved visualization of the ablation area compared to traditional or conventional treatments. The all-optical ultrasound transducer and / or the silicon photonics-based ultrasound transducer can allow electromagnetic interference-free detection of ultrasound during ablation treatment.

[0073] The ablation systems and probes of the present disclosure provide other advantages over conventional systems and devices. In some examples, the probes of the present disclosure can provide clear 360° boundary imaging of the bubble cloud registered with shear wave elastography (SWE) imaging, which provides further information about tissue vitality. The improved imaging of the bubble cloud allowed by the probes of the present disclosure can be used with elastic imaging and can be combined. The bubble cloud represents a high echo volume and produces excellent contrast with the surrounding tissue. For example, the image of the bubble cloud provided by the probe of the present disclosure can produce excellent contrast with soft liver tissue with clear boundaries. As will be further described below, the ablation system of the present disclosure can be used in various modes, including shear wave elastography (SWE) mode, to provide information about necrosis or other characteristics of the target tissue.

[0074] The ablation systems of the present disclosure may include one or more probes, including those described above. Figure 4-Figure 6Examples of probes that may be used and contemplated for use in the ablation system of the present disclosure are shown in FIG. Figure 4 , a first example probe 400 is shown. The probe 400 may include an imaging sensor 420 and a radio frequency (RF) transmitter 430. The RF transmitter 430 may be configured as a radio frequency electrode, a microwave (MW) antenna, etc. The probe 400 may include a tubular shaft 405. The tubular shaft may define an internal hole and may be cylindrical in shape. The tubular shaft 405 may extend axially and terminate at a distal end 408. Although not shown, in some examples the distal end 408 may be pointed. During an ablation treatment or other therapy, the probe 400 may be inserted into a patient at a target tissue. The RF transmitter 430 may be energized to produce an ablation volume 410. The imaging sensor 420 may also be operated to produce an imaging field 440 that may collect imaging data of the ablation volume 410 and the target tissue.

[0075] The imaging sensor 420 can be located in the shaft 405 and can be coupled to the imaging generator via a connector 425. In some examples, the imaging sensor 420 can be an all-optical ultrasound transducer and the connector 425 can be an optical fiber. In other examples, other imaging sensors, such as electronic ultrasound sensors, can be used. The RF transmitter 430 can be coupled to the RF generator via an appropriate cable (not shown), which can also extend from the RF transmitter through the shaft to the generator. As shown, the probe 400 can include both the imaging sensor 420 and the RF transmitter 430. The imaging sensor 420 and the RF transmitter 430 can be positioned adjacent to each other and / or spaced apart from each other at a predetermined distance. The position of the imaging sensor 420 relative to the RF transmitter allows the imaging field 440 to be located at the ablation volume 410. In this way, imaging data for the ablation volume can be collected without interference from surrounding tissue or other body structures, and there is no need to position the imaging sensor separately or independently relative to the RF transmitter and / or the ablation volume.

[0076] In some examples, the imaging sensor 420 emits an imaging field 440 and can be rotated within the axis 405 to allow up to 360° viewing and mapping of the ablation area 410. Imaging data can be collected, for example, in cross-sectional slices. The imaging sensor 420 can be coupled to a connector 425 (e.g., an optical fiber) using a fiber optic rotary joint (FORJ) and / or a mechanical clamp ring (SR), which can allow rotation of the imaging sensor 420. In other examples, a combined SR-FORJ arrangement can be used. Although not shown, the antenna 430 can be connected to a generator via a wire that can generate microwave energy or other signals to be emitted from the antenna 430. In some examples, the connector 425 can be rotated to rotate the sensor 420. In other examples, the sensor 430 can be configured as a phased array of transducers as described above. In such an example, the connector 425 can be stationary and non-rotating because such rotation is not required to obtain 360° imaging. In other examples, multiple wires or connectors 425 may be positioned in the shaft 405, with each wire coupling a transducer in the transducer array to an imaging generator, controller, or computing device.

[0077] As described, connectors 425 and cables connecting imaging sensor 420 and RF transmitter 430, respectively, to their corresponding generators may be routed through shaft 405. In other examples, one or the other or both of connector 425 and cable may be routed external to shaft 405, embedded in a wall of shaft 405, or routed along shaft 405. In still further examples, connector 425 and / or cable may be located in a separate conduit structure along shaft 405.

[0078] In some examples, the probe 400 can be operated to simultaneously power on the RF transmitter 430 and obtain imaging data via the imaging sensor 420. This operation is possible because the imaging sensor 420 can be configured as an all-optical ultrasound transducer, which is not affected by interference between the all-optical ultrasound transducer and the RF transmitter 430 (e.g., a microwave antenna) because the optical signal of the all-optical ultrasound transducer is not interfered by the electromagnetic noise caused by the RF transmitter 430. In other examples (such as embodiments using piezoelectric transducers or other transducers), ablation and imaging operations can be performed alternately to prevent electromagnetic interference. For example, an ablation cycle can be performed for 1 minute and then turned off for a period of 5 seconds, during which imaging can be performed using a piezoelectric transducer or other transducer. In other examples, other cycle times can be used.

[0079] In the illustrated example, the probe 400 is configured to provide imaging data from inside the ablation volume 410. In other examples, the imaging sensor 420 and the RF transmitter 430 can be positioned relative to each other, or other / additional imaging sensors can be positioned to obtain imaging data from areas outside the ablation volume 410. For example, the imaging sensor 420 can be positioned farther from the distal end 408 and / or the RF transmitter 430 so that the imaging field 440 captures imaging data outside the ablation volume 410. In still other examples, the positions of the RF transmitter 430 and the imaging sensor 420 can be reversed, whereby the imaging sensor 420 is positioned closer to the distal end 408 and the RF transmitter is positioned farther from the distal end 408. Figure 5 This configuration is shown in FIG. 4. The ablation probe 401 includes Figure 4 400. In other examples, the imaging sensor 420 may be configured to obtain forward-looking imaging information. In such an example, the imaging field may extend forward from the probe 400 in the overall axial direction of the probe 400 from the distal end 408. The sensor 420 may be positioned in other configurations to obtain imaging information in other directions relative to the axis of the probe 400. Such an imaging field 440 may be vertically aligned, tilted, or generally aligned or parallel to the axis of the probe 400. In yet other examples, other configurations may be used.

[0080] Figure 6 Another example probe 402 is shown in FIG. In this example, the probe 402 includes more than one imaging sensor. The probe 402 can be configured similarly to the probe 400 described previously, but can include more than one imaging sensor. As shown, the probe 402 can include a first imaging sensor 420A and a second imaging sensor 420B. Each of the imaging sensors 420A and 420B can be various suitable imaging sensors, such as an all-optical ultrasound transducer. Each of the imaging sensors 420A and 420B can be connected to an appropriate imaging generator via corresponding connectors 425A and 425B. In the example shown, the first imaging sensor 420A is positioned at a predetermined distance from the distal end 408 and is farther away from the distal end 408 than the RF transmitter 430. The second imaging sensor 420B can be positioned closer to the distal end 408 than the RF transmitter 430. In this arrangement, the RF transmitter can be positioned between the first imaging sensor 420A and the second imaging sensor 420B. In other examples, other arrangements can be used.

[0081] In other examples (not shown), the imaging sensors may be positioned such that one imaging sensor collects imaging data from inside the ablation volume 410 and a second imaging sensor collects imaging data from outside the ablation volume. In still other examples, more than two imaging sensors may be used. In other examples, multiple imaging sensors may be positioned farther from the distal end 408 than the RF transmitter 430 so that the multiple imaging sensors are positioned on the same axial / longitudinal side of the RF transmitter. In such an example, two or more imaging sensors may be positioned adjacent to each other without an RF transmitter in between. In still other examples, other configurations and arrays of imaging sensors may be used.

[0082] Figure 7 Another example probe 403 is shown in FIG. In this example, the probe 403 may include more than one shaft or conduit. In this example, the probe 403 may include a first shaft 407 and a second shaft 409. The first shaft 407 and the second shaft 409 may be configured as various structures. In some examples, each of the first shaft 407 and the second shaft 409 may be a cylindrical or tubular structure. In other examples, the first shaft 407 and the second shaft 409 may have a semicircular cross-sectional shape. In this example, the first shaft 407 and the second shaft 409 may be joined together to form a probe 403 having a circular outer contour. In other examples, other shapes and structures may be used.

[0083] The first shaft 407 and the second shaft 409 can be joined together using various suitable joining methods and / or accessories. In some examples, the first shaft 407 and the second shaft 409 can be joined together using adhesives, riveting, welding or a joining process. In yet other examples, the probe housing can be formed as a single piece to have the first shaft 407 and the second shaft 409.

[0084] In the example shown, imaging sensor 420 and connector 425 are positioned in first axis 407, and RF transmitter and cable 435 can be positioned in second axis 409. In this way, imaging components and RF components can be separated and / or insulated from each other. In other examples, probe 403 can include more than two axes. For example, such an embodiment can be used in the case where probe 403 includes more than one imaging sensor. In such an example, each imaging sensor and corresponding connector in the imaging sensor can be located in a separate axis or conduit.

[0085] Reference now Figure 8, another mode of operation of the probe 400 is shown. As shown, the probe of the present disclosure can be operated in a shear wave elastography (SWE) mode. This mode of operation can be performed in addition to the previously described up to 360° volume imaging mode of operation. In this example mode of operation, the probe 400 can be used. The probe 400 shown can be configured as previously described. In addition, other configurations, variations, and example probes can also be operated in a similar manner.

[0086] As shown, the probe 400 can be operated to energize the RF transmitter 430 to produce an ablation volume 410. This high temperature area around the distal end of the probe 400 can cause destruction of the target tissue. In addition, a coagulation necrosis zone 550 can be produced. The imaging field 440 of the imaging sensor 420 can be used in a shear wave elastography (SWE) mode to collect elastic imaging data. Such data can measure the elasticity and / or stiffness of the tissue in the imaging field. The coagulation necrosis zone 550 can have elastic imaging properties that are different from those of the surrounding tissue. The imaging sensor 420 can be used to collect such information to characterize the properties of the tissue and prepare an elastic imaging map that can be superimposed on an image of the tissue. This can allow more information to be conveyed to medical professionals to determine the performance of the ablation treatment and to determine what actions (if any) should be taken during the ablation procedure. This information and the SWE mode of operation can be performed during the ablation treatment and / or simultaneously with the ablation of the target tissue.

[0087] When operating in the SWE mode of operation, the probe 400 allows volumetric imaging of the ablation zone 410 using pulse echo ultrasound and simultaneously allows visualization of the coagulation necrosis 550 based on shear wave elastography. In this mode of operation, the transceiver 430 can use acoustic radio frequency force pulses to collect information about the elasticity of the surrounding tissue. Information about the elasticity of the tissue in the necrotic zone 550 in the ablation zone 410 can be used to determine the characteristics of the ablation treatment. The information collected during the SWE mode of operation can be used, for example, to create an elastography map 620, such as Fig. 9 As shown in Figure 900( Fig. 9 ), an elastic imaging map 620 can be superimposed on an ultrasound (or other) image. The elastic imaging map 620 can provide information about the size, location, and elasticity of tissue in the ablation area. This information can be used in conjunction with other imaging and information to provide feedback about the ablation process. The combination of elastic imaging data collected by the probe 400 can be used to generate an image 800 that shows the location of the probe 600, the bubble cloud 610, and the elastic imaging map 620.

[0088] In other ablation systems and methods of the present disclosure, more than one probe may be used in an ablation procedure. In such a configuration, any of the various probes previously described may be used, and each of the probes may have the same configuration or be different from one another. The operation of more than one probe may be multiplexed. For example, if multiplexed, the operation of the RF transmitters in the multiple probes may be pulsed individually.

[0089] The probes of the present disclosure (including the examples previously described) can be single-use and / or disposable. In other examples, the probes can be reusable. The probes can also be user-configurable to arrange the type, location, and relative positioning of the RF / MW antenna / electrodes, imaging sensors, and / or markers relative to the axis. The ability to flexibly configure the probe enables the user to adjust the probe to a specific patient and ablation situation.

[0090] Reference now Fig.10 , an example method 1000 for performing ablation or RF therapy is shown. The example method 1000 can be performed using one of the ablation systems previously described, which can include one or more of the probes detailed above. Although the method 1000 is described below using one or more example ablation systems and / or probes, it should be understood that the method 1000 is not limited to the specific examples detailed below, and other alternative embodiments and examples of the ablation systems and probes disclosed herein can also be used.

[0091] Method 1000 can start at step 1002, where the RF transmitter is powered on. Although not shown, before performing step 1002, the probe of the ablation system can be positioned at or near the target tissue that requires RF treatment. For example, the distal end of the probe can be inserted into the patient and inserted into the target tissue. The RF transmitter can be located inside the probe or integrated into the probe, such as the probe described for example probes 20, 22, 24, 400, 401, 402. The RF transmitter (such as an RF electrode or MW antenna) can be powered by supplying power to the RF transmitter from an RF generator. This can be automatically caused by a computer, controller or other processing device, or can be started by a medical professional operating the ablation system. After the RF transmitter is powered on, the RF energy can generate an ablation volume at or around the target tissue, as previously described.

[0092] At step 1004, first imaging data may be obtained. The first imaging data may be obtained from a first direction relative to the target tissue. The first imaging data may be obtained from a first imaging sensor. The first imaging sensor may be located on the probe and may obtain imaging data from a location inside the patient and / or inside the ablation volume. In other examples, the first imaging data may be obtained from a location outside the patient, such as by an external ultrasound transducer or from a stereotactic imaging device. The first imaging data may provide imaging information of one side of the target tissue or from an angle.

[0093] At step 1006, second imaging data may be obtained. The second imaging data may be obtained from a second direction relative to the target tissue. The second direction may be different from the first direction of step 1004. The imaging data from the second direction may provide imaging information of a side of the ablation volume that is different from the first direction. The second imaging data may provide a more complete and / or more comprehensive view of the ablation volume and the target tissue. The second imaging data may be obtained from any suitable imaging sensor as described above. In some examples, the second imaging data may be obtained from an imaging sensor positioned on a probe that also includes an RF transmitter powered on at step 1002. In other examples, both the first imaging sensor that provides the first imaging data at step 1004 and the second imaging sensor that provides the second imaging data at step 1006 are positioned on a probe that includes an RF transmitter powered on at step 1002. In yet other examples, the first imaging data and the second imaging data are obtained from imaging sensors located on different components of the ablation system.

[0094] At step 1008, the first imaging data and the second imaging data are combined. Since the first imaging data and the second imaging data are obtained from the first direction and the second direction, respectively, a more complete image of the target tissue and / or ablation volume can be obtained than using conventional imaging or ablation methods. The first imaging data and the second imaging data can be executed by an imaging engine, which can be operated to receive the first imaging data and the second imaging data. The imaging engine can be a component of an appropriate workstation, server, computer or other processing device. Although not shown, the imaging engine can also display a combined image of the target tissue and / or ablation volume to a medical professional. The combined image can generate up to 360° images of the target tissue and / or ablation volume to the medical professional in real time.

[0095] Method 1000 may be performed at least in part using a probe that includes an all-optical ultrasound transducer as an imaging sensor. In such an example, step 1002 may be performed simultaneously with at least one of step 1004 and / or step 1006. The all-optical ultrasound transducer may acquire imaging data while the RF transmitter is powered on.

[0096] It should be understood that the foregoing description is merely an illustration of the present invention. Those skilled in the art may devise various alternatives and modifications without departing from the present invention. Therefore, the present invention is intended to encompass all such alternatives, modifications and variations that fall within the scope of the appended claims.

Claims

1. An ablation device, comprising: axis; a radio frequency (RF) transmitter positioned in the shaft to deliver radio frequency (RF) energy to create an ablation volume; as well as An imaging sensor, positioned in the shaft, is configured to obtain imaging data of the ablation volume.

2. The ablation device according to claim 1, wherein: The shaft includes a distal end that is positioned at or near target tissue during an ablation procedure; and The RF transmitter is positioned closer to the distal end than the imaging sensor.

3. An ablation device according to claim 1 or 2, wherein the RF transmitter comprises a microwave (MW) antenna.

4. The ablation device of claim 1 or 2, wherein the RF transmitter comprises a radio frequency (RF) electrode.

5. The ablation device of any preceding claim, wherein the imaging sensor comprises an ultrasound transducer.

6. The ablation device of any preceding claim, wherein the imaging sensor comprises an all-optical ultrasound transducer.

7. An ablation device according to any one of the preceding claims, wherein the imaging device is configured to operate simultaneously with the RF transmitter during an ablation procedure.

8. The ablation device of any of the preceding claims, wherein the imaging sensor is a first imaging sensor and the ablation device further comprises a second imaging sensor positioned in the shaft.

9. The ablation device of claim 8, wherein the RF transmitter is positioned between the first imaging sensor and the second imaging sensor.

10. An ablation device according to any of the preceding claims, wherein the imaging device is configured to operate in an imaging mode to collect imaging data and in a shear wave elastography (SWE) mode to collect elastography data from the ablation volume.

11. An ablation system, comprising: a probe configured to deliver RF energy to a target tissue in a patient; a first imaging sensor positioned to obtain first imaging data from a first direction relative to the target tissue; as well as a second imaging sensor positioned to obtain second imaging data from a second direction relative to the target tissue; The first direction and the second direction are different, and the second imaging sensor is located inside the patient.

12. The ablation system of claim 11, wherein the second imaging sensor is located in the probe.

13. The ablation system of claim 11 or 12, wherein the second imaging sensor is configured to operate simultaneously with operation of the probe.

14. The ablation system of claim 11, 12 or 13, wherein both the first imaging sensor and the second imaging sensor are located in the probe.

15. The ablation system of any one of claims 11 to 14, wherein the second imaging sensor is located in the probe and comprises an all-optical ultrasound transducer.

16. A method of performing radiofrequency (RF) ablation, comprising: energizing an RF transmitter located at or near target tissue in a patient; obtaining first imaging data from a first direction relative to the target tissue; obtaining second imaging data from a second direction relative to the target tissue, and The first imaging data and the second imaging data are combined to create an image of the ablation volume. The method of claim 16 , wherein the second direction corresponds to a direction from inside the patient.

18. The method of claim 16 or 17, wherein the step of energizing the RF transmitter is performed simultaneously with at least one of obtaining the first imaging data and obtaining the second imaging data.

19. The method of claim 16, 17 or 18, wherein the first direction and the second direction correspond to opposite sides of the target tissue.

20. The method of any one of claims 16 to 19, wherein the second imaging data is obtained from an all-optical ultrasound transducer.

21. A method according to any one of claims 16 to 20, comprising performing a method of radio frequency (RF) therapy.

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