Directional cryoablation system

Abstract

A cryoablation system capable of assuming a directionally active state and including a cryoablation probe and a controller is provided. [Solution] The cryoablation probe has an active area including a cooling chamber and a heating chamber facing the cooling chamber, the cooling chamber and the heating chamber being insulated from each other to minimize energy loss between them, thereby selectively and directionally forming ice at a target site. The cooling chamber can include a temperature sensor and an exhaust tube passing through the probe to direct a fluid or gas exhibiting a Joule-Thomson cooling effect. The heating chamber can include a temperature sensor and a heating core having a heating zone. A controller of the cryoablation system processes temperature measurement data from the sensors in the heating chamber and the cooling chamber, and adjusts the heating zone based on the processed temperature measurement data to maintain a sufficiently constant temperature, thereby mitigating or preventing ice formation on the heating chamber.

Description

Related Application

[0001] This application claims the priority of U.S. Patent Application No.17 / 979,963, filed on November 3, 2022, entitled "Directional Cryoablation System". The entire content of this application is incorporated herein by reference. Technical Field

[0002] The present application generally relates to directional cryoablation systems. Background Art

[0003] Cryoablation is a surgical procedure that uses liquid or gas to freeze and destroy abnormal tissue. Cryoneurolysis is the intentional freezing of a nerve so as to induce reversible ablation of the nerve and reduce subsequent nerve regeneration. Recently, the combination of cryoneurolysis science and imaging guidance (e.g., computed tomography scan, fluoroscopy, ultrasound, etc.) has resulted in countless targets for systemic nerves for pain management, such as minimally invasive surgery that does not require opioid drugs or high-risk surgery. Currently, practitioners interested in cryoneurolysis use tumor cryoablation probes, which are small metal needles with a diameter of less than about 2.4 millimeters (mm), have symmetrically arranged internal components and energy that flows linearly through the needle, so as to maximize the area of ablated tissue. These needle probes are designed to destroy tumor cells and need to reach temperatures lower than about -40°C. The probe can be inserted into the tumor, and high-pressure gas (e.g., argon gas, etc.) can flow through the needle. When argon gas expands, the surrounding volume is cooled (Joule-Thomson (JT) effect), which results in an elliptical ablation zone where the tumor is engulfed by ice at approximately -140°C. The airflow is opened and closed to induce osmotic gradient shifts that lead to cell lysis and tumor rupture. This effect is highly reliable in tumor cryoablation because the probe is inserted into the tissue and the damage is non-discrete and extensive.

[0004] Unlike cryo-thawing, this method does not allow for the insertion of a probe into the nerve, as the probe could cause unnecessary mechanical damage and pain. Furthermore, the ideal temperature for inducing ice crystallite formation within the nerve membrane is approximately -20°C, typically maintained for at least 10 minutes. When performing cryo-thawing, the probe is usually positioned parallel to the target nerve, which presents various challenges to the use of conventional probes, including non-target damage, inaccuracy in the ablation zone of the target nerve, and unpredictable and unknown in-body target tissue temperatures. This can lead to serious adverse consequences, including postoperative pain, organ damage, and even death.

[0005] The success of cryothrolysis surgery is closely related to exposing the target nerve to the correct amount of cooling temperature and maintaining the correct duration. If the temperature is too low and the duration is too long, irreversible nerve ablation can occur, potentially resulting in permanent nerve loss for the patient. If the temperature is too low and the duration is too short, partial ablation may occur, leading to reduced or absent treatment effectiveness.

[0006] Currently, when measuring the temperature of the target tissue during ablation surgery, the operator typically inserts a second probe near the target tissue. However, due to the difficulty in correctly positioning the second probe, the increased surgical time, and the increased risk of patient injury, the insertion of this second probe is quite difficult. Alternatives to inserting the second probe are estimated by calculations based on temperature data from gels, etc., from bench tests or core probe temperatures. These methods assume ideal conditions and have been shown to differ from the actual temperature obtained from the patient. Therefore, when performing cryoablation surgery, it is necessary to obtain an actual temperature measurement of the target tissue.

[0007] Furthermore, a key obstacle to achieving the necessary low-temperature exposure is considering differences in body weight index and composition among patients. A higher body weight index results in a greater heat load on the device within the patient's body. This leads to unpredictable and variable ablation zones and treatment outcomes. Therefore, when performing cryoablation surgery, it is necessary to control the temperature of the ablation zone.

[0008] Furthermore, the objective of cryoneurolysis is to ablate the target nerve while preserving the surrounding structure. This is difficult to achieve with current tumor ablation devices, which create a large elliptical freezing zone (e.g., area of ​​freezing), and these devices ablate all nearby target (e.g., nerves) and non-target (e.g., organs, bones, muscles) structures. Damage to non-target structures is common and has been shown to lead to additional postoperative pain and even death. Protective techniques such as water separation, carbon dioxide pneumoperitoneum separation, and balloon spacer techniques can be used. In particular, current clinical practice to reduce non-target damage involves injecting air or saline solution into the site to separate the non-target structure from the target tissue. However, such methods are cumbersome and require continuous monitoring and repositioning because the injected gas or fluid diffuses. Also, significant probe movement necessitates re-imaging to evaluate the probe's position. All of the above techniques increase surgical time, radiation exposure, and can affect probe performance. Therefore, when performing cryoablation surgery, alternatives are needed to avoid non-target damage. [Overview of the Initiative]

[0009] The present invention provides a cryoablation system capable of exhibiting directional active and non-directional active states. The cryoablation system may include a cryoablation probe (also referred to herein as the “probe”) and a controller. The cryoablation probe is positioned at the ablation target site and includes a shaft, which may have an outer surface, an inner surface, a distal portion, a proximal portion, a first side, and a second side opposite the first side. The probe may include an active region located at the distal portion of the shaft. The active region may include a cooling chamber located at the first side of the shaft and a heating chamber located at the second side of the shaft. The cooling chamber and the heating chamber are insulated from each other to minimize energy loss between them, so that ice is selectively formed at the target site in the directional active state of the cryoablation system. The cooling chamber may include an exhaust pipe with a capillary inside, which is arranged to guide a fluid or gas exhibiting a Joule-Thomson cooling effect through the shaft. The heat exchanger coil may be installed above the capillary. The cooling chamber may further include at least one temperature sensor installed adjacent to the exhaust pipe. The heating chamber may include a heating plate, at least one temperature sensor installed adjacent to the heating plate, and a heating core located between the exhaust pipe and the heating plate. The heating core may include heating zones. The cryoablation system may further include a controller operably connected to the cryoablation probe. The controller may include a processor and memory.The memory may have computer-executable commands stored therein, which, when executed by the processor, cause the controller to process temperature measurement data from at least one sensor in the heating chamber and at least one sensor in the cooling chamber, and to adjust the heating area of ​​the heating core based on the processing of the temperature measurement data, thereby mitigating or preventing ice formation in the heating chamber during the directional active state of the cryoablation system by maintaining a sufficiently constant temperature. [Brief explanation of the drawing]

[0010] [Figure 1] This is a plan view of a cryoablation probe according to one aspect of the present disclosure. [Figure 2] This is a side view of the active region of a cryoablation probe according to one aspect of the present disclosure. [Figure 3] This is a perspective view of the active region of a cryoablation probe according to one aspect of the present disclosure, showing the internal components of the active region of the cryoablation probe. [Figure 4] This is a cross-sectional view of the active region of a cryoablation probe according to one aspect of the present disclosure. [Figure 5] This is a plan view of a cryoablation probe according to one aspect of the present disclosure, showing the window of the cooling chamber of the cryoablation probe. [Figure 6] This is a perspective view of the active region of a cryoablation probe according to one aspect of the present disclosure, showing the internal components of the working region of the cryoablation probe. [Figure 7] This is a plan view of the heating core of the heating chamber of a cryoablation probe according to one aspect of the present disclosure. [Figure 8] This is a side view of the heating chamber of a cryoablation probe according to one aspect of the present disclosure. [Figure 9] Figure 8 is a magnified view of the thermocouple wires near the heating chamber. [Figure 10] Figure 8 is an enlarged view of the distal thermocouple wire in the heating chamber. [Figure 11] This is a block diagram illustrating an exemplary component of a controller for a cryoablation system according to one aspect of the present disclosure. [Figure 12] This is a schematic diagram showing the formation of directional ice after activating a cryoablation probe. [Figure 13] This is a schematic diagram illustrating the circumferential ice formation after activating a cryoablation probe. [Modes for carrying out the invention]

[0011] This disclosure relates to cryoablation probes and cryoablation systems, including cryoablation probes and systems. Where used in reference to the elements described herein, unless otherwise specified, the terms “one / one type” and “the said” include at least one or more of the said elements, including combinations thereof. Also, unless otherwise specified, the terms “or” and “and” mean “and / or” and combinations thereof. “Basically” means that the distance, shape or arrangement of the said elements does not need to have the mathematically precise distance, shape or arrangement of the said elements, but may have the distance, shape or arrangement that a person skilled in the art would normally or approximately recognize as having the said distance, shape or arrangement of the said elements. Accordingly, “basically” means the degree of completeness or near-completeness of the characteristic, property, state or structure. The degree of exact tolerance deviation from the characteristic, property, state or structure has the same overall result as when an absolute characteristic, property, state or structure is obtained. Unless otherwise specified, the terms “first,” “second,” etc. are used to distinguish one element from another and are not used quantitatively. Therefore, the “first” element described below will also be referred to as the “second” element. Members “connected to,” “operably connected to,” “installed adjacent to,” “installed between,” “installed in,” and “located between” other members can be interposed between members, as long as the cryoablation system can perform the aforementioned objectives. Unless otherwise specified, the order of operations (or steps) is not limited to the order shown in the claims or drawings. As used herein, “patient” includes mammals such as humans. While the drawings show combinations of several elements of the cryoablation system and cryoablation probe, it should be noted that such elements may be included in other embodiments or aspects shown in other drawings. That is, each aspect and embodiment of this disclosure may be considered independently or in combination with other aspects and embodiments of this disclosure.

[0012] This specification provides cryoablation systems that can be used to freeze and destroy diseased tissue, including nerve ablation. For example, cryoablation systems have solved important problems related to monitoring the temperature of the ablation zone and minimizing non-target damage. In particular, cryoablation systems such as those disclosed herein can provide measurement of the actual target tissue temperature from the cryoablation probe itself, can control the temperature and duration of the cold energy delivered when insertion of a second needle is not required, can control the temperature of the ablation zone using an integrated tissue temperature measurement system and also using real-time temperature-based feedback, can generate a directional cryozone when it does not affect the surrounding tissue, can generate specific ablation zone shapes and sizes for various indications regardless of the ablation energy mode, can prevent or mitigate bridging, and / or can control the rate and flow rate of energy to maximize energy transfer into the target tissue and minimize non-target damage. Note that "bridging" usually refers to bridging through tissue or bridging through the probe. When ice generated from both edges of the cooling chamber extends into the tissue and connects with each other, bridging occurs through the tissue, positioning the ice radially outward from the heater cell. This causes the ice to surround the heating chamber (but not necessarily form on top of the heating chamber). Temperature measurements detected by the heating chamber sensor (discussed later) can have characteristic curves that can be used to detect bridging. For example, a gradual decrease in temperature as detected by the sensor indicates that bridging is occurring through the tissue, and the cooling energy of the cooling chamber suppresses the heating core, triggering a process in which directional freezing near the cooling chamber recovers. Bridging through the probe occurs when the cooling chamber suppresses the heating core, conducts cooling energy through the outer surface of the probe, and ice forms directly on the surface of the probe. Temperature measurements by the heating chamber sensor (discussed later) can have characteristic curves that can be used to detect bridging.For example, if the sensor shows a rapid drop in temperature, it indicates that bridging is occurring via the probe, and the cooling energy from the cooling chamber can suppress the heating core and trigger a process in which directional freezing recovers.

[0013] Generally, a cryoablation system may include a handle that an operator can grip to operate the cryoablation probe, a vacuum tube to prevent freezing of inactive areas of the cryoablation probe, an exhaust pipe for recirculating a fluid or gas that can exhibit a Joule-Thomson cooling effect from the cryoablation probe, an electromagnetic sensor located within the cryoablation probe to track its position, a copper coil array as a heat exchanger to increase the cooling power of the cryoablation probe, a heating core and heating plate for generating and supplying heat to create a directional thermal gradient, a thermocouple or other thermal sensor to measure the temperature at a specific point to ensure a successful directional ablation zone, a gas connector for flowing pressurized gas to the cryoablation probe, and an electrical connector for matching the cryoablation probe to an electronic device on a console and for programming and identifying the probe placement.

[0014] Referring particularly to Figures 1 and 2, the cryoablation system 10 may include a probe 12, a handle 14, a connector 16, and a controller (not shown). The probe 12 may include a shaft 18, the shaft 18 having a distal portion 20, a proximal portion 22, a first side 24, and a second side 26 opposite the first side 24. The probe may be a needle with a diameter of approximately 1.5 mm to approximately 3.5 mm. Other diameters are also possible. The distal portion 20 may include an active area 28 that can generate a cryoablation zone in patient tissue when activated. The active area may include a heating chamber and a cooling chamber of mixture that can generate a directional and positionable cryoablation zone (for example, one side of the probe may reach the cryoablation temperature, while the other side may be kept at a temperature close to body temperature). Referring particularly to Figures 2 and 3, the active area 28 may include a cooling chamber 30 located on the first side 24 of the shaft 18 and a heating chamber 32 located on the second side 26. Referring further to Figure 12, in the directional active state of the cryoablation system, ice forms on the first side 24 of the active region 28 of the shaft 18 or in its vicinity, rather than on the second side 26 of the active region 28 of the shaft 18 or its vicinity (e.g., cryogenic zone 25). The directional cryogenic zone can extend laterally from the center of the probe by about 1.5 cm to about 2.0 cm. These values ​​are illustrative only, and the directional cryogenic zone can extend to other distances. Referring to Figure 13, in the non-directional active state of the cryoablation system, the heating chamber is not active, and the formation of ice 27 is not limited to the first side 24 of the active region 28 of the shaft 18 or its vicinity, but may also form circumferentially, for example, in or near the active region of the probe. Referring to Figures 3 and 4, the cooling chamber 30 and the heating chamber 32 may be separated by a distance D. The heating chamber and the cooling chamber are insulated from each other to minimize energy loss between them, and ice is selectively formed at the target site in the directional active state of the cryoablation system. The heating chamber can be installed extending radially outward from the central axis CA through the shaft.The cooling chamber and heating chamber can be insulated from each other to minimize energy loss, thereby causing the freezing temperature around the cryoablation probe to be less than 360° in the directional active state of the cryoablation system.

[0015] Referring to Figure 3, the cooling chamber 30 may include an exhaust pipe 34 arranged to guide a fluid or gas exhibiting the Joule-Thomson cooling effect into the shaft 18. The fluid or gas may be any suitable fluid or gas capable of exhibiting the Joule-Thomson cooling effect, such as argon, nitrogen, or oxygen. The exhaust pipe may have a closed distal end to include all the airflow within it. In particular, referring to Figure 6, an open-end capillary 44 may be installed inside the exhaust pipe 34. The heat exchanger coil may be installed above the capillary tube. A pressurized cryogenic gas or fluid can flow from a console (connected to a cryogenic gas or fluid source) and enter the probe shaft via the capillary 44. As the gas or fluid leaves the capillary, the pressurized gas or fluid expands and the pressure of the gas or fluid decreases. The gas or fluid then passes through the inner chamber of the exhaust pipe back to the console and is discharged into the ambient environment. This pressure drop results in a change of kinetic energy and is explained by the Joule-Thomson effect. As the gas expands, the pressure of the gas or fluid decreases, causing a rapid drop in the surrounding area (inside and outside the probe). This cooling causes the moisture in nearby tissues to freeze, leading to ice formation.

[0016] Referring to Figures 2, 4, and 5, the shaft on the first side of the active region of the cryoablation probe can be limited to an opening window 38 and an exhaust pipe 34 installed within the opening window 38. This allows the exhaust pipe to be directly exposed to the target tissue site. The window can extend less than 180°, enclosing the active region of the shaft of the cryoablation probe, in order to control and limit the "range" of freezing. As shown in Figures 3, 4, and 6, the exhaust pipe 34 can include a basic elliptical cross-sectional shape. An elliptical exhaust pipe 34 can reduce the diameter of the exhaust lumen 40 when connected to the copper coil 42, and can be used for fluid or gas heat transfer by ensuring sufficient contact between the copper coil 42 (which serves as a heat exchanger to increase the cooling power of the cooling chamber), the capillary 44, and the exhaust pipe 34. Additionally, an elliptical exhaust pipe can create sufficient space for sensors (as described below) installed on the surface of the exhaust pipe. The exhaust pipe may have other shapes.

[0017] Returning to FIG. 3, the heating chamber 32 can include a heating plate 46 and a heating core 48. The heating core 48 can be positioned between the exhaust pipe 34 and the heating plate 46. The heating core can include heating zones. Referring to FIG. 7, the heating core 48 can include at least two independently controlled heating zones 50 and 52, wherein the heating zones 50 and 52 can generate a specific amount of thermal energy to reduce or prevent ice formation in or around the heating chamber. The heating zone 50 may be positioned at a distal portion of the heating core, and the heating zone 52 may be positioned at a proximal portion of the heating core. Preferably, two or more zones are positioned longitudinally adjacent to each other such that there is only no or minimal "unheated" area of the heating core. At least two zones are required due to different temperature gradients along the longitudinal axis of the probe generated by the Joule-Thomson effect. This allows the heating chamber to apply a minimal amount of heat to prevent bridging, while at the same time not interrupting the probe regeneration cycle by heating the exhausted gas or fluid. Alternatively, the heating core can include a single heating zone with a variable width trace, thereby achieving the effect of two zones. In other words, the heater trace can be arranged to have a smaller / larger width to provide a similar effect to that obtained with two zones. A smaller / thinner trace results in more heating. A wider / thicker trace results in less heating. This allows the trace width / thickness to be modulated to simulate variable resistance, and thus variable heating can be generated in a single zone.

[0018] The heating core can have a basic concave arrangement. A concave arrangement means that the heater is positioned as far away from the exhaust pipe as possible using a conical needle. The heating core may have other arrangements. The heating plate can provide a rigid, smooth, and non-invasive outer surface to the heating core and sensors (as described below). It can also function as a heat sink to equalize the temperature of at least two independently controlled zones. For example, the heating plate can be made of stainless steel. Other materials are also possible. The heating core can contain constantan laminated between polyamide sheets, but other materials are also possible.

[0019] The insulating material can isolate the heating chamber from the cooling chamber and minimize the amount of cooling energy that can flow into the heating chamber. The insulating material can bias the cooling gradient towards the first side of the probe's working area and maximize ice deposition at the target tissue site. In particular, referring to Figure 4, in one embodiment, a layer 66 of a material with high thermal conductivity and low conductivity can be provided between the heating core 48 and the heating plate 46 (for example, it can be laminated on the inner surface of the heating plate), and a layer 68 of a material with low thermal conductivity and low conductivity can be installed between the heating core 48 and the exhaust pipe 34 (for example, it can be laminated on the inner surface of the heating plate). The material may be an epoxy resin material for adhesion to the member. As described above, by making the high thermal conductivity and low conductivity material installed between the heating core and the heating plate adhere to the heating plate, the thermal gradient of the heating core can be biased towards the outside of the heating plate, and the heat flow from the heating chamber to the cooling chamber can be minimized. In other words, such high thermal conductivity and low conductivity materials can maximize the heating gradient toward the outside of the tissue, thereby minimizing the adverse effect of the heating core on freezing. Excessive heat transfer from the heating core to the exhaust pipe can adversely affect the size of the target ablation zone. Furthermore, such high thermal conductivity and low conductivity materials can ensure sufficient heating of the heating chamber, preventing or mitigating freezing or heat energy transfer within the heating chamber. A layer of low thermal conductivity and low conductivity material placed between the heating core and the exhaust pipe can limit the transfer of heat / cold gradients within the probe. This material can be filled into the space between the heating core and the exhaust pipe. Such materials promote the directional freezing zone (i.e., freezing) between the heating chamber and the cooling chamber. Without such materials, the cooling power of the cooling chamber may suppress the heating core, preventing the directional freezing zone from being achieved. The heating chamber should only become unsafe when clinically necessary, and the low thermal conductivity and low conductivity material helps ensure this property.

[0020] Referring to Figures 3 and 8-10, the cooling chamber 30 includes at least one temperature sensor, for example, a proximal temperature sensor. The cooling chamber may optionally include at least two temperature sensors 54a and 54b located near the exhaust pipe 34. The heating chamber may include at least one temperature sensor, for example, a proximal temperature sensor. The heating chamber 32 may optionally include at least two temperature sensors 56a and 56b, which may be installed adjacent to the heating plate 46. The at least two temperature sensors 54a and 54b of the cooling chamber 30 may be located in the proximal portion 58 and the distal portion 60 of the cooling chamber 30, respectively, and the at least two temperature sensors 56a and 56b of the heating chamber 32 may be located in the proximal portion 62 and the distal portion 64 of the heating chamber 32, respectively. As shown in Figures 9 and 10, the temperature sensors may be thermocouple wires. In particular, for the cooling chamber, a distal sensor is installed on the outer surface of the exhaust pipe to measure the temperature between the cooling chamber and the heating chamber near the capillary opening. This temperature can be used to verify whether maximum performance has been reached by detecting the temperature cooling rate, and to adjust heating and cooling to achieve the formation of a directional refrigeration zone. A proximal sensor may be installed on the outer surface of the exhaust pipe between the cooling chamber and the heating chamber, and can be used to measure the temperature near the edge of the target ablation site before the gas is discharged from the active region of the probe. This temperature measurement can also be used to verify whether maximum performance has been reached by detecting the temperature cooling rate, and to adjust heating and cooling to achieve the formation of a directional refrigeration zone. For the heating chamber, the distal sensor may be mounted between the heating plate and the heating core within the epoxy resin layer. This distal sensor can be used to measure the temperature of the distal portion of the heating chamber. The trend in the heating curve can be used to detect ice formation (i.e., bridging) outside the target ablation site, adjust the heating power, and ensure heating at a safe temperature.The proximal sensor can be used to measure the temperature of the proximal portion of the heating chamber, and can also be used to monitor trends in the heating curve, detect ice formation outside the target ablation site (i.e., bridging), adjust heating power, and ensure heating at a safe temperature.

[0021] The cryoablation system may further comprise a distal inactive region distal to the heating core of the cryoablation probe, and the cryoablation probe comprises an insulating sleeve arranged to prevent or minimize freezing around the inactive region of the cryoablation probe. A portion of the exhaust pipe adjacent to the active region may be provided on the insulating sleeve.

[0022] Referring to Figure 11, the cryoablation system may include a controller 70 operably connected to the cryoablation probe and including a processor 72 and memory 74. The memory 74 may have computer-executable commands 76 stored therein, which, when executed by the processor 72, cause the controller 70 to process temperature measurement data from at least one sensor in the heating chamber and at least one sensor in the cooling chamber. The commands may also cause the controller 70 to adjust the heating zones of the heating core (or at least two independently controlled zones 50, zone 52 of the heating core 48 in some embodiments) based on the processing of the temperature measurement data to maintain a sufficiently constant temperature, thereby mitigating or preventing freezing in the heating chamber in the directionally active state of the cryoablation system. In particular, the heating core may be controlled by the controller to maintain a constant temperature on the probe surface. Thermocouples or other thermal sensors may be strategically positioned, and the controller receiving temperature measurement data from the sensors may prevent bridging and ensure that the probe does not overheat to unintended tissue burns. Embodiments having at least two zones of a heating core regulated by a controller are advantageous because the cooling energy generates an energy gradient along the axis of the probe, typically becoming colder at the distal end. The distal heating core typically consumes twice the power of the proximal heating core. With at least two heating zones, the controller can also adjust the introduction of the minimum amount of heat to prevent bridging, thereby reducing interference with the low-temperature cooling cycle.

[0023] The controller may be a proportional-integral-derivative (PID) controller. A sensor can be used to determine tissue temperature measurements in real time and transmit them to the PID controller. The PID controller can adjust the gas / fluid flow duty cycle and heating array temperature to achieve the desired shape, size, and temperature of the freezing zone. In particular, as a supplement or alternative to the above commands, the controller may have computer-executable commands stored in memory, which, when executed by the processor, cause the controller to perform other steps. For example, such commands may include: processing based on temperature measurement data to monitor ice bridging around or on the cryoablation probe; processing based on temperature measurement data to confirm the timing of gas or fluid transport from the exhaust pipe; processing based on temperature measurement data to confirm the timing of heating the heating chamber; processing based on temperature measurement data to stop heating the heating chamber or fluid or gas when a critical value is reached; monitoring the cooling rate of the cooling chamber and adjusting the cooling rate based on temperature measurement data obtained from the proximal and distal temperature sensors of the cooling chamber; monitoring the heating rate of the heating chamber and adjusting the heating rate based on temperature measurement data obtained from the proximal and distal temperature sensors of the heating chamber; adjusting the flow rate of fluid or gas passing through the exhaust pipe based on processing of temperature measurement data; adjusting the power level of the heating chamber (e.g., including each heating zone of at least two independently controlled zones of the heating core) based on processing of temperature measurement data; and combinations thereof.

[0024] Memory 74 may contain computer-readable commands, which, when executed by processor 72, cause the controller to perform various functions belonging to the controller throughout this disclosure. Computer-readable commands may be coded within memory 74. Memory may include any non-temporary computer-readable storage medium, including volatile, non-volatile, magnetic, optical, or dielectric, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), electrically erasable programmable ROM (EEPROM), flash memory, or any other digital medium, with the sole exception being temporary propagating signals.

[0025] As a non-limiting example of a proposed technique for generating directional ice, it may include transporting a gas or fluid for two minutes while adjusting the heater power using temperature sensor readings. In particular, the amount of time the gas or fluid is transported can be determined by the curve of temperature sensor data. The protocol may also include stopping the transport of the gas or fluid for 30 seconds if the heating core power decreases according to the curve of temperature sensor data. For example, this cycle may be repeated five times to generate ice of a desired size. Such a protocol is merely illustrative, and other protocols can be used to generate frozen zones of a desired size, shape, and arrangement.

[0026] A cryoablation system may include other components, such as a console. The console can provide many different functions. For example, it can regulate gas pressure and flow rate, supply power to the probes and electronic devices within the console, and house probe position tracking circuits, a computer, and a touch panel monitor. The console can immediately power and control multiple cryoablation probes. Argon gas, or other fluids or gases exhibiting a Joule-Thomson cooling effect, can be connected to the console inlet port, flow through a regulator and dryer, and exit the console by controlling the gas flow through the probe's gate valve. Power means can be arranged to supply sufficient power to all electronic devices inserted within the cryoablation probes. A microcontroller can monitor the compliance and safety of the entire system.

[0027] Compared to thermotherapy such as radiofrequency, microwave, laser, or ultrasound, focused cryoablation systems are highly suitable for pain management because they result in less postoperative pain or neuroma formation. The system can be used to treat various pain symptoms, such as chronic abdominal pain (for example, the target nerve may be a visceral nerve connected to the intra-abdominal plexus), phantom limb pain, pudendal neuralgia, and groin pain. Other conditions that can be treated include chronic diseases resulting from abnormal nerve activity, such as sexual dysfunction, tachycardia, diabetes, and obesity.

[0028] Each aspect and embodiment disclosed in this disclosure may be considered independently or in combination with other aspects, embodiments, and modifications of this disclosure. Furthermore, some features of the embodiments and embodiments of this disclosure may be shown only in some drawings or otherwise described in some parts of this disclosure, and these features may be combined with other embodiments and embodiments shown in other drawings or other parts of this disclosure. Similarly, some features of the embodiments and embodiments of this disclosure shown in some drawings or otherwise described in some parts of this disclosure may be optional and may be omitted from these embodiments and embodiments. Also, when describing scope, all points within that scope are included in this disclosure. Furthermore, unless otherwise specified, none of the steps of the methods of this disclosure are limited to any particular order of execution. Furthermore, all references incorporated herein by reference are incorporated herein by their entirety.

Claims

1. A cryoablation system having a directional active state and a non-directional active state, wherein the cryoablation system includes a cryoablation probe and a controller, and the cryoablation probe is used to ablate a target site. The cryoablation probe includes a shaft and an active region. The shaft has an outer surface, an inner surface, a distal portion, a proximal portion, a first side, and a second side, the first side facing the second side. The active region is located in the distal portion of the shaft and includes a cooling chamber located on the first side of the shaft and a heating chamber located on the second side, wherein the cooling chamber and the heating chamber are insulated from each other to minimize energy loss between them, so that ice is selectively formed on the target site in the directional active state of the cryoablation system. The cooling chamber includes an exhaust pipe, a heat exchanger coil, and at least one temperature sensor. The exhaust pipe includes a capillary installed inside the exhaust pipe, and the exhaust pipe is arranged to guide a fluid or gas exhibiting a Joule-Thomson cooling effect through the shaft. The heat exchanger coil is placed over the capillary, The at least one temperature sensor of the cooling chamber is installed adjacent to the exhaust pipe, The heating chamber includes a heating plate, at least one temperature sensor, and a heating core. The at least one temperature sensor of the heating chamber is installed adjacent to the heating plate, The heating core is located between the exhaust pipe and the heating plate and includes a heating zone. The controller is operably connected to the cryoablation probe, and the controller includes a processor and a memory, the memory having computer-executable commands stored in the memory, and the computer-executable commands are executed by the processor when they are executed. Processing temperature measurement data from at least one temperature sensor in the heating chamber and temperature measurement data from at least one temperature sensor in the cooling chamber, A cryoablation system characterized in that, based on the processing of temperature measurement data, the controller is instructed to adjust the power level of the heating zone of the heating core so as to maintain a constant temperature on the surface of the cryoablation probe, thereby mitigating or preventing ice formation in the heating chamber during the directional active state of the cryoablation system.

2. The cryoablation system according to claim 1, characterized in that the heating zone includes at least two independently controlled heating zones, and adjusting the heating zone includes adjusting the at least two independently controlled heating zones.

3. The cryoablation system according to claim 1, characterized in that the heating zone includes a single heating zone having variable resistance, and adjusting the heating zone includes adjusting the single heating zone having variable resistance.

4. The at least one temperature sensor of the heating chamber includes at least two temperature sensors, The at least one temperature sensor in the cooling chamber includes at least two temperature sensors, The cryoablation system according to claim 1, characterized in that the processing of temperature measurement data includes processing temperature measurement data from at least two sensors in the heating chamber and temperature measurement data from at least two sensors in the cooling chamber.

5. The heating chamber comprises at least two temperature sensors, a proximal temperature sensor located in the proximal portion of the heating chamber and a distal temperature sensor located in the distal portion of the heating chamber. The cryoablation system according to claim 4, characterized in that at least two temperature sensors of the cooling chamber include a proximal temperature sensor located in the proximal portion of the cooling chamber and a distal temperature sensor located in the distal portion of the cooling chamber.

6. The cryoablation system according to claim 1, characterized in that at least one temperature sensor in the heating chamber and at least one temperature sensor in the cooling chamber are thermocouples.

7. The cryoablation system according to claim 1, characterized in that the cooling chamber and the heating chamber are insulated from each other so that, in the directional active state of the cryoablation system, ice less than 360° is formed around the cryoablation probe.

8. The cryoablation system according to claim 1, further comprising: a layer of a material having high thermal conductivity and low electrical conductivity, installed between the heating core and the heating plate; and a layer of a material having low thermal conductivity and low electrical conductivity, installed between the heating core and the exhaust pipe.

9. The cryoablation system according to claim 8, characterized in that the material having high thermal conductivity and low electrical conductivity is an epoxy resin, and the material having low thermal conductivity and low electrical conductivity is an epoxy resin.

10. The cryoablation system according to claim 1, characterized in that the cooling chamber and the heating chamber are insulated from each other so that when the cryoablation system is in a directional active state, the cryoablation temperature is generated only on the first side of the cryoablation probe.

11. The cryoablation system according to claim 1, characterized in that an opening window is provided on the first side shaft of the cryoablation probe, and the exhaust pipe is installed inside the opening window.

12. The cryoablation system according to claim 1, characterized in that the cryoablation probe has a central axis that penetrates the shaft along the longitudinal direction of the cryoablation probe, and the heating core is installed radially outward from the central axis.

13. The cryoablation system according to claim 1, characterized in that the size and arrangement of the heating chamber and the cooling chamber are also designed so that ice is generated circumferentially on the target site when the cryoablation system is in a non-directional active state.

14. The cryoablation system according to claim 1, further comprising computer-executable commands stored in the memory, wherein the computer-executable commands, when executed by the processor, cause the controller to monitor ice bridging around the cryoablation probe or ice bridging on the cryoablation probe based on the processing of the temperature measurement data.

15. The cryoablation system further includes computer-executable commands stored in the memory, and when the computer-executable commands are executed by the processor, Based on the processing of the temperature measurement data, the timing of supplying fluid or gas through the exhaust pipe is confirmed, The cryoablation system according to claim 1, characterized in that the controller is instructed to confirm the timing for heating the heating chamber based on the processing of the temperature measurement data.

16. The cryoablation system further includes a computer-executable command stored in the memory, wherein when the computer-executable command is executed by the processor, it causes the controller to stop heating the heating chamber, the fluid, or the gas when the temperature measured by the temperature sensor reaches a threshold based on the processing of the temperature measurement data, characterized in that the cryoablation system according to claim 1.

17. The cryoablation system further includes computer-executable commands stored in the memory, and when the computer-executable commands are executed by the processor, The cooling rate of the cooling chamber is monitored, and the cooling rate is adjusted based on temperature measurement data obtained from the proximal and distal temperature sensors of the cooling chamber. The cryoablation system according to claim 5, characterized in that the controller is instructed to monitor the heating rate of the heating chamber and to adjust the heating rate based on temperature measurement data obtained from the proximal temperature sensor and distal temperature sensor of the heating chamber.

18. The cryoablation system according to claim 1, further comprising computer-executable commands stored in the memory, wherein the computer-executable commands, when executed by the processor, cause the controller to adjust the flow rate of the fluid or gas passing through the exhaust pipe based on the processing of the temperature measurement data.

19. The cryoablation system according to claim 1, further comprising computer-executable commands stored in the memory, wherein the computer-executable commands, when executed by the processor, cause the controller to adjust the power level based on the processing of the temperature measurement data.

20. The cryoablation system according to claim 1, further comprising a handle located at the proximal end of the proximal portion of the shaft, wherein the handle comprises at least one electromagnetic sensor, and at least one electromagnetic sensor of the handle is arranged to track the position of the cryoablation probe.

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