Cryoablation needle with J-T slot sleeve

Abstract

The present invention discloses a cryoablation needle with a JT slot sleeve, comprising a vacuum wall, a JT slot and a JT slot sleeve, the vacuum wall comprises a needle bar and an inner tube, the distal end of the needle bar has a needle tip, the inner tube is drilled into the needle bar, a sandwich is formed between the inner tube and the needle bar, the distal end of the inner tube has a first predetermined distance between the distal end of the needle bar, the JT slot and the JT slot sleeve are fitted to the inner tube, the JT slot sleeve is fitted to the distal end of the JT slot, the JT slot sleeve is movable relative to the JT slot, among the regions distributed along the axial direction of the vacuum wall, the region where the sandwich is located is a vacuum insulation region, the region where the first predetermined distance is located is a target region, the distal end of the JT slot sleeve comprises at least two adjustment positions relative to the vacuum wall, the first adjustment position is in the target region, and the second adjustment position is in the vacuum insulation region. The present invention significantly accelerates the cooling rate by switching the distal end of the JT slot sleeve between at least two adjustment positions.

Description

Technical Field

[0001] The present invention relates to the technical field of cryoablation, and particularly to a cryoablation needle with a J-T slot sleeve.

Background Art

[0002] Cryoablation is a treatment method that destroys pathological tissues by low temperature, and is considered to be a very effective and minimally invasive treatment method for malignant tumors. The cryoablation technology is easy to operate, has few complications, high analgesic effect, and the boundary of the ice ball formed for ablation is clear and easy to observe, so that lesions close to large blood vessels and important organs can be safely ablated. Furthermore, cryoablation can also take the form of multi-needle cryoablation, enabling a wider range of ablation, and is suitable for large lesions and lesions with irregular shapes.

[0003] When cells are frozen, first ice crystals are formed outside the cells, causing an increase in the concentration of solutes outside the cells, resulting in a hypertonic environment. The water inside the cells enters outside the cells, causing dehydration inside the cells. The cells that have lost water become wrinkled, the cell membrane is deformed, causing "solution damage" in a highly toxic environment. At the same time, the ice crystals formed inside the cells directly damage the cell organelles and cell membrane, causing further necrosis generally called "intracellular ice damage". Since intracellular ice damage directly damages the cell structure, the destructive power to cells is stronger. Generally, the slower the cooling rate of the cells, the higher the probability of "solution damage" occurring, and the faster the cooling rate, the more likely "intracellular ice damage" is induced. Therefore, in cryoablation surgery for tumors, a faster cooling rate is generally required, so that the tumor can be more thoroughly killed and the treatment time can be significantly saved.

[0004] The development of cryoablation technology has gone through three stages. The first stage is the liquid nitrogen transportation refrigeration technology that feeds liquid nitrogen at -196°C to the tip of the cryoablation needle at a low driving pressure to achieve the purpose of cryoablation. In this technology, the cold source completely depends on liquid nitrogen. However, liquid nitrogen is in the main unit or the liquid nitrogen tank with a long transportation distance from the needle tip. During the process of transporting liquid nitrogen, the temperature of the needle tip will not reach -196°C until the entire transportation pipeline reaches -196°C. Therefore, the cooling rate of liquid nitrogen refrigeration is the slowest in the existing technology. The second stage is the direct throttling refrigeration technology. This technology utilizes the principle of the "Joule Thomson Effect" (abbreviated as J-T), transports normal temperature ultra-high pressure gas into the J-T slot (capillary tube that generates the J-T effect) inside the cryoablation needle for direct throttling treatment to lower the temperature. Its cooling rate is relatively the fastest among the existing technologies. However, the structures such as the J-T slot and fin tube inside the needle still consume a part of the cold air, resulting in a long cooling time. Also, the penetration rate of the ultra-high pressure gas used is low and it is expensive, so it is difficult to popularize this technology. The third stage is the throttling refrigeration technology with precooling. Its principle is that after precooling a general industrial gas at normal temperature with a related main unit, it is transported into the J-T slot inside the cryoablation needle for throttling treatment to reach an ablation temperature lower than the precooling temperature. This technology solves the problem of high-cost and scarce gas sources. By combining with the throttling refrigeration technology, its cooling rate is much faster than that of the liquid nitrogen refrigeration technology. However, compared with the direct throttling refrigeration technology, its cooling rate is still slow.

Summary of the Invention

Problems to be Solved by the Invention

[0005] In response to the above problems of the prior art and to solve the problem of the slow cooling rate of the prior art, the present invention proposes a cryoablation needle with a J-T slot sleeve.

[0006] To solve the above technical problems, the present invention is realized by the following technical solutions.

[0007] The present invention provides a cryoablation needle with a J-T slot sleeve, which includes a vacuum wall, a J-T slot, and a J-T slot sleeve. Here, the vacuum wall includes a needle rod and an inner tube, the distal end of the needle rod has a needle tip, the inner tube is bored through the needle rod, and a Layer structure is formed between the inner tube and the needle rod. The Layer structure is capable of forming a vacuum Layer structure and is the distal end of the inner tube has a first predetermined distance from the distal end of the needle rod along the axial direction of the vacuum wall. The distal end of the inner tube is the Tip-side end of the inner tube and is the J-T slot sleeve is fitted to the distal end of the J-T slot and inserted into the distal end of the J-T slot. The distal end of the J-T slot is the Tip-side end of the J-T slot and is the J-T slot and the J-T slot sleeve are bored through the inner tube, among the regions distributed along the axial direction of the vacuum wall in the vacuum wall, the region where the Layer structure is located is a vacuum insulation region, and the region where the first predetermined distance is located is a target region. the distal end of the J-T slot is located in the vacuum insulation region, the J-T slot sleeve is movable relative to the J-T slot along the axial direction of the vacuum wall, and a dynamic seal is formed between the J-T slot sleeve and the J-T slot. the distal end of the J-T slot sleeve is switchable between at least two adjustment positions relative to the vacuum wall. The at least two adjustment positions include a first adjustment position and a second adjustment position. the first adjustment position is within the target region, the second adjustment position is within the vacuum insulation region, When the distal end of the J-T slot sleeve is in the first adjustment position, the distal end of the J-T slot sleeve has a second predetermined distance from the needle tip along the axial direction of the vacuum wall, and the second predetermined distance is at least such that the ice ball formed by freezing Realize a covering situation covers When the distal end of the J-T slot sleeve is in the second adjustment position, the distal end of the J-T slot sleeve has a third predetermined distance from the distal end of the vacuum insulation region along the axial direction of the vacuum wall, and the third predetermined distance is at least such that after the refrigerant is discharged from the J-T slot sleeve, directly from within the vacuum insulation region Realize a returning situation , the distal end of the vacuum insulation region is the Tip-side end above.

[0008] Preferably, it further includes a J-T slot sleeve adjusting device, and the J-T slot sleeve adjusting device is used to switch the distal end of the J-T slot sleeve between the at least two adjustment positions.

[0009] Preferably, the J-T slot sleeve adjusting device includes a pressing tube and a mandrel, where the mandrel is provided along the axial direction of the vacuum wall, the pressing tube is bored through the mandrel, the distal end of the pressing tube is connected to the proximal end of the J-T slot sleeve, and the distal end of the pressing tube is the Tip-side end above of the pressing tube, the pressing tube and the J-T slot sleeve can be controlled to move synchronously along the axial direction, thereby switching the distal end of the J-T slot sleeve between adjustment positions.

[0010] Preferably, it further includes a seal assembly, and the seal assembly is used to form a dynamic seal between the mandrel and the pressing tube.

[0011] Preferably, the seal assembly includes a seal ring, a seal groove, and a seal pressing member, where the seal groove is fixedly sealed with the proximal end of the mandrel, the seal ring is provided between the mandrel and the seal groove, and the seal pressing member is provided between the seal ring and the seal groove, the seal pressing member is controlled to be pressed in the radial direction, and further capable of pressing the mandrel against the seal ring in the radial direction, whereby a dynamic seal is formed between the mandrel and the pressing tube.

[0012] Preferably, it further includes a spring and a snap member, where one end of the spring is movable in synchronization with the distal end of the J-T slot sleeve and is also connected to the snap member, and the snap member is capable of entering and leaving the snap position, the other end of the spring is fixed to the vacuum wall, when the snap member is in the snap position, the spring is held in a deformed state by the restriction of the snap member, and the distal end of the J-T slot sleeve is in the second adjustment position, the deformation done state is a compressed state or an extended state, when the snap member disengages from the snap position, the spring is capable of generating a restoring force to return from the deformed done state to the natural state, and the restoring force is capable of driving the distal end of the J-T slot sleeve from the second adjustment position to the first adjustment position.

[0013] Preferably, the snap member includes a positioning pin and a C-ring, where the positioning pin is provided on the C-ring, the C-ring is covered by an outer wall with a fixed relative position to the vacuum wall, When the distal end of the J-T slot sleeve is in the first adjustment position, the positioning pin is used to hold the spring in the deformed done state.

[0014] Preferably, it further includes a slider and a lever, where the lever is provided at the proximal end of the vacuum wall, the position of the lever relative to the vacuum wall is constant, and the proximal end of the vacuum wall is the End on the side opposite to the tip thereof, the slider is connected to the proximal end of the pressing tube and further directly or indirectly connected to the snap member, and the proximal end of the pressing tube is the End on the side opposite to the tip thereof, the slider, the pressing tube and the J-T slot sleeve can be controlled to move synchronously along the axial direction, thereby switching the adjustment position of the distal end of the J-T slot sleeve, the lever is provided with a lever positioning groove, and the slider is provided with a slider positioning groove, the positioning pin is controlled to be inserted into the slider positioning groove and the lever positioning groove at the same time, and it is further possible to keep the relative position of the slider relative to the lever and the vacuum wall constant. At this time, the distal end of the J-T slot sleeve is in the second adjustment position.

[0015] Preferably, the vacuum wall further includes an outer tube, where the distal end of the outer tube is hermetically connected to the proximal end of the needle bar, the proximal end of the outer tube is hermetically connected to the proximal end of the inner tube, the distal end of the outer tube is the Tip-side end thereof, and the proximal end of the outer tube is the End on the side opposite to the tip thereof, the outer diameter of the outer tube is larger than the outer diameter of the needle bar, and the inner diameter of the outer tube is larger than the inner diameter of the needle bar, From the distal end to the proximal end of the inner tube, the inner tube sequentially includes a front section of the inner tube and a rear section of the inner tube. The outer diameter of the rear section of the inner tube is larger than the outer diameter of the front section of the inner tube, and the inner diameter of the rear section of the inner tube is larger than the inner diameter of the front section of the inner tube. The front section of the inner tube is perforated in the needle rod, and the rear section of the inner tube is perforated in the outer tube.

[0016] Preferably, the dynamic seal point between the J-T slot sleeve and the J-T slot is located at the proximal end of the J-T slot sleeve. The dynamic seal point is located inside the rear section of the inner tube.

[0017] Preferably, it further includes a temperature measurement line. The distal end of the temperature measurement line is a temperature measurement point, and the distal end of the temperature measurement line is the Tip-side end in the temperature measurement line. The temperature measurement point is provided at the distal end of the J-T slot sleeve and is used to measure the temperature at the distal end of the J-T slot sleeve.

[0018] Compared with the prior art, the present invention has the following advantages.

[0019] (1) In the cryoablation needle with a J-T slot sleeve provided by the present invention, by fitting the J-T slot sleeve on the J-T slot, the J-T slot sleeve can move axially with respect to the J-T slot. When the distal end of the J-T slot sleeve is located inside the vacuum insulation region, when the refrigerant fluid is passed through the J-T slot, refrigeration starts, and all the transport pipelines on the host side and the cryoablation needle side can be pre-purged (cooled). Moreover, since there is no cold air consumption in the target area during this pre-purge process, all the cold air is used for cooling the transport pipelines. As a result, the cooling process of this transport pipeline is the fastest. Furthermore, since no cold air is released in the target area during the pre-purge, frosting and freezing do not occur in the target area, and the formal treatment can be directly implemented.

[0020] (2) In the cryoablation needle with a J-T slot sleeve provided by the present invention, after pre-purging, the cryoablation needle is not cooled only in the target area of the vacuum wall. When the distal end of the J-T slot sleeve is located in the target area and the refrigerant fluid is passed through the J-T slot, freezing starts, and all the heat loads are only in the target area and the tumor tissue outside it. Therefore, the cooling rate of this freezing process is significantly accelerated.

[0021] (3) In the cryoablation needle with a J-T slot sleeve provided by the present invention, after the tool test process is completed, the purge mode can be kept on to maintain the inside of the vacuum insulation area (the distal end of the J-T slot sleeve) at the lowest temperature, and no cold air is released in the target area. Therefore, operations such as puncture, scanning, and positioning can be performed. After being punctured at a predetermined position, it is adjusted to the freezing mode. At that time, the inside of the target area can be directly instantaneously lowered from room temperature to the lowest temperature, which enables extremely rapid cooling in the formal treatment stage.

[0022] (4) The cryoablation needle with a J-T slot sleeve provided by the present invention has a wide range of applications and can be applied to all existing cryoablation technologies such as liquid nitrogen transport refrigeration technology, direct throttling refrigeration technology, and throttling refrigeration technology through precooling. It is applicable not only to percutaneous puncture cryoablation instruments but also to cryoablation instruments for natural orifice procedures.

[0023] Of course, any product implementing the present invention does not necessarily need to achieve all the above advantages simultaneously.

Brief Description of the Drawings

[0024] To more clearly explain the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the following description of the embodiments or the prior art will be briefly introduced. Naturally, the drawings in the following description are only some embodiments of the present invention, and those skilled in the art can obtain other drawings based on these drawings without creative effort.

Figure 1

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Figure 5

Figure 6

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Figure 8

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Figure 11

Figure 12

Modes for Carrying Out the Invention

[0025] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. It is obvious that the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments that can be obtained by those skilled in the art without creative efforts shall fall within the protection scope of the present invention.

[0026] In the description of the specification of the present invention, it should be understood that terms such as "upper part", "lower part", "upper end", "lower end", "lower surface", "upper surface", etc. indicate the orientation or positional relationship based on that shown in the accompanying drawings, and are only intended to facilitate and simplify the description of the present invention, and do not indicate or imply that the mentioned device or element must have a specific orientation and be structured and operated in a specific orientation, and thus should not be construed as a limitation of the present invention.

[0027] In the description of the specification of the present invention, the terms "first" and "second" are only used for the purpose of description, and should not be understood as indicating or implying relative importance, or implicitly designating the number of the indicated technical features. Therefore, the features limited by "first" and "second" may explicitly or implicitly include one or more such features.

[0028] In the description of the present invention, "a plurality" means, for example, two, three, four, etc. unless otherwise specifically limited.

[0029] The following will specifically describe the technical solutions of the present invention by way of specific examples. These specific examples below can be combined with each other, and in some examples, the same or similar concepts and processes are not repeated.

[0030] FIG. 1 and FIG. 2 are diagrams showing the adjustment principle of the J-T slot in a cryoablation needle with an adjustable position of the J-T slot according to an embodiment of the present invention.

[0031] Referring to FIGS. 1 and 2, the cryoablation needle with an adjustable position of the J-T slot according to this embodiment includes a vacuum wall 2, a J-T slot 1, and a J-T slot sleeve 18.

[0032] The vacuum wall 2 includes a needle rod 21 and an inner tube 22. The distal end of the needle rod 21 has a needle tip 211. The inner tube 22 is bored through the needle rod 21, and there is Layer structure formed therebetween, Layer structure which can form a vacuum, either a permanent vacuum Layer structure or a real-time evacuation Layer structure and can play a role in heat insulation and preventing frostbite of normal tissues. Layer structure The inner tube 22 has a first predetermined distance between its distal end and the distal end of the needle rod (this first predetermined distance can be understood as the interval distance along the axial direction of the vacuum wall). The distal end of the inner tube 22 is close to the needle tip 211 of the inner tube 22

[0033] at the end side of which is (Tip-side end) the end part.

[0034] Among the regions distributed along the axial direction of the vacuum wall, since the Layer structure vacuum can play a role in heat insulation, Layer structure the region where the

[0035] is located is the vacuum insulation region 26, and the region where the first predetermined distance is located is the target region 25. side of The J-T slot sleeve 18 is fitted to or inserted into the distal end of the J-T slot 1. The distal end of the J-T slot 1 is close to the needle tip 211 of the J-T slot 1 (Tip-side end) at the end

[0036] In FIGS. 1 and 2, the J-T slot sleeve 18 is fitted to the distal end of the J-T slot 1. In another embodiment, the J-T slot sleeve 18 may be inserted into the distal end of the J-T slot 1.

[0037] The J-T slot sleeve 18 is movable relative to the J-T slot 1 along the axial direction of the vacuum wall, and a dynamic seal is formed between the J-T slot sleeve 18 and the J-T slot 1.

[0038] The distal end of the J-T slot sleeve is switchable between at least two adjustment positions (e.g., by movement along the axial direction of the vacuum wall) relative to the vacuum wall, and the at least two adjustment positions include a first adjustment position and a second adjustment position. When the distal end of the J-T slot sleeve 18 is in the first adjustment position, as shown by the dashed lines in FIGS. 1 and 2, the distal end of the J-T slot sleeve 18 is located within the target region 25 and may be understood to be in the refrigeration mode. The distal end of the J-T slot 1 is close to the tip 211 of the J-T slot 1. side of end (Tip-side end) When the distal end of the J-T slot sleeve 18 is in the second adjustment position, as shown by the solid lines in FIGS. 1 and 2, the distal end of the J-T slot sleeve 18 is located within the vacuum insulation region 26 and may be understood to be in the pre-purge mode.

[0039] When the distal end of the J-T slot sleeve 18 is in the first adjustment position, the distal end of the J-T slot sleeve 18 has a second predetermined distance from the tip along the axial direction of the vacuum wall. The second predetermined distance is at least such that the ice ball formed by refrigeration covers the tip, that is, after the refrigerant fluid is discharged from the J-T slot sleeve, from the inside of the target region and the inside of the vacuum insulation region. Realize a returning situation Here, while the refrigerant fluid returns from the inside of the target region, it exchanges heat with the substances outside the entire target region.

[0040] When the distal end of the J-T slot sleeve 18 is in the second adjustment position, the distal end of the J-T slot sleeve 18 has a third predetermined distance from the distal end of the vacuum insulation region along the axial direction of the vacuum wall. The third predetermined distance is at least such that after the refrigerant fluid is discharged from the J-T slot sleeve, directly from the vacuum insulation region. Realize a returning situation, only relatively static refrigerant exists in the target area, and there is no heat exchange with substances outside the target area. That is, during refrigeration, the refrigerant does not release any cooling capacity in the target area. The distal end of the vacuum insulation area is the aforementioned Tip-side end of the vacuum insulation area.

[0041] It can be understood that the first predetermined distance, the second predetermined distance, and the third predetermined distance here are the interval distances along the axial direction of the vacuum wall 2. Furthermore, all the axial directions described later can be understood as the axial direction of the vacuum wall 2.

[0042] In one embodiment, the vacuum wall is a vacuum wall of a rigid material applicable to a percutaneous cryoablation device. As shown in FIG. 1, the needle tip 211 is in the form of a tip.

[0043] In one embodiment, the vacuum wall is a vacuum wall of a flexible material applicable to an ablation device for natural orifice. As shown in FIG. 2, the needle tip 211 is in the form of an arc. Preferably, the needle rod 21 and the inner tube 22 can be made of a soft non-metallic material or a metal material that can be freely bent, such as PTFE or a PTFE braided tube or a stainless steel bellows.

[0044] In one embodiment, the usage process of the above cryoablation needle with a J-T slot sleeve is as follows. Before the treatment, take out the cryoablation needle in the purge mode, connect it to the main unit, insert the needle rod 21 (at least the target area 25) of the cryoablation needle into the physiological saline, activate the tool test function. In the tool test, first execute the rewarming stage. When the temperature of the needle tip rises to a predetermined temperature within a certain period of time, it is proved that the rewarming function is normal. Immediately afterwards, the program automatically executes the freezing stage. When the temperature of the needle tip drops to a predetermined temperature within a certain period of time, it is proved that the freezing function is normal. At this time, to fully purge, the time to keep the needle tip at the lowest temperature can be appropriately extended, and then the tool test is automatically stopped. In the freezing stage, it is possible to observe whether there is frost in the vacuum insulation area 26. If there is no frost, it is proved that the insulation function is normal. Observe whether there is gas leakage at the needle tip immersed in physiological saline in all stages. If there is no leakage, it is proved that the airtightness is normal. At the end of the tool test, both the main unit and the transport pipeline of the cryoablation needle complete the purge (cooling). Immediately afterwards, the freezing function can be turned on first (or the individually set purge function can be turned on). The freezing at this stage is carried out at a low operating pressure or can be intermittently ventilated. In this way, while maintaining the temperature at the distal end of the J-T slot at the lowest temperature, the gas consumption can be saved. Next, with the freezing function turned on, percutaneous puncture can be performed under image guidance to reach the desired tumor position with the needle tip. In this case, the movement to the distal end of the J-T slot can be adjusted, stopped at the first adjustment position, and switched to the freezing mode. Since the entire transport pipeline is in a low-temperature state, the cooling heat load of the cryoablation needle is only on the target area 25 and the tumor tissue outside it. Therefore, even if it is switched to the freezing mode, the temperature at the distal end of the J-T slot can be maintained at the lowest temperature, but the outer wall of the target area 25 instantaneously drops from room temperature to below -100°C.In this way, the ablation treatment time for tumors of the same size is shortened, or a larger ablation range (ice ball) is formed within the same time. Moreover, since the tumor tissue is cooled more rapidly, the probability of damage to tumor cells due to intracellular ice significantly increases. Subsequently, the cryogenic damage to tumor cells becomes more thorough, and the ablation effect becomes better.

[0045] In a preferred embodiment, it further includes a J-T slot sleeve adjustment device, and the J-T slot sleeve adjustment device is used to switch the distal end of the J-T slot sleeve between at least two adjustment positions.

[0046] In one embodiment, referring to FIGS. 3, 5, 8, and 9, the J-T slot sleeve adjustment device includes a pressing tube 17 and a mandrel 3. Here, the mandrel 3 is provided along the axial direction of the vacuum wall 2, and the pressing tube 17 is drilled through the mandrel 3. The distal end of the pressing tube 17 is connected to the proximal end of the J-T slot sleeve 18, and the distal end of the pressing tube 17 is close to the needle tip 211 of the pressing tube 17 side of end (Tip-side end) is. The pressing tube 17 and the J-T slot sleeve 18 can be controlled to move synchronously along the axial direction, thereby switching the distal end of the J-T slot sleeve 18 between adjustment positions.

[0047] In one embodiment, it further includes a seal assembly 5, and the seal assembly 5 is used to form a dynamic seal between the mandrel 3 and the pressing tube 17.

[0048] In one embodiment, referring to FIGS. 3, 5, 8, and 9, the seal assembly 5 includes a seal ring 51, a seal groove 52, and a seal pressing member 53. Here, the seal ring 51 is placed in the seal groove 52, and the seal pressing member 53 is screwed into the seal groove 52 along the axial direction. Thereby, the seal ring 51 is fixed between the seal groove 52 and the seal pressing member 53. The mandrel 3 is inserted into the seal ring 51 and the seal pressing member 53, so that the seal ring 51 is radially pressed between the mandrel 3 and the seal groove 52 to cause deformation and form a dynamic seal. Optionally, the seal ring 51 may be a rubber seal ring such as a nitrile O-ring, or a Variseal ring of a fluorine-based polymer + metal spring with low-temperature resistance.

[0049] In a preferred embodiment, referring to FIG. 7, the vacuum wall of the flexible cryoablation needle may further include a vacuum three-way tube 28, a vacuum connecting tube 291, a vacuum hose 292, and a return air connecting tube 293. Here, the proximal end of the inner tube 22 is hermetically connected to the distal end of the return air connecting tube 27, the proximal end of the outer tube 23 is hermetically connected to the three-way tube connection portion 281, the proximal end of the vacuum three-way tube 28 is hermetically connected to the return air connecting tube 27, the distal end of the vacuum connecting tube 291 is inserted into the three-way tube bypass 282, the vacuum hose 292 is inserted into the vacuum connecting tube 291, and by evacuating the proximal end of the vacuum hose 292, the gap between the inner tube 22 and the outer tube 23 can be maintained in a vacuum state, and frostbite of the wall of a normal natural opening can be prevented.

[0050] In one embodiment, referring to FIGS. 8 and 9, it further includes a shunt tube 294 for sealing the gap between the intake pipe 6, the return air pipe 7, and the mandrel 3, and the intake pipe 6, the return air pipe 7, and the mandrel 3 are inserted into and sealed at the proximal end of the shunt tube 294. In one embodiment, the adjustment of the position of the J-T slot sleeve can be achieved by manual back-and-forth adjustment or by the prehub spring 120, and further includes a snap member 10. Here, one end of the spring 120 is movable in synchronization with the distal end of the pressing tube 17 and is also connected to the snap member 10. The snap member 10 can enter and leave the snap position. The other end of the spring 120 is fixed to the vacuum wall. Referring to FIGS. 3 and 8, when the snap member 10 is in the snap position, the spring 120 is held in a deformed state by the restriction of the snap member 10, and the distal end of the J-T slot sleeve 18 is in the first adjustment position. Referring to FIGS. 5 and 9, when the snap member 10 is disengaged from the snap position, the spring 120 can generate a restoring force to return from the deformed done state to the natural state, and the restoring force can drive the movement of the pressing tube 17 and further drive the J-T slot sleeve 18 to advance from the first adjustment position to the second adjustment position.

[0051] In one embodiment, referring to FIG. 3, the distal end of the spring 120 has a constant relative position with respect to the vacuum wall, and the proximal end of the spring 120 is connected to the snap member 10. When the J-T slot sleeve 18 is in the first adjustment position, the deformation done state of the spring 120 is an extended state. Referring to FIG. 5, when the snap member 10 is disengaged from the snap position, the restoring force (tensile force) of the spring 120 drives the pressing tube to move toward the distal end, and further drives the J-T slot sleeve 18 to advance from the first adjustment position to the second adjustment position.

[0052] In another embodiment, the relative position between the proximal end of the spring 120 and the vacuum wall remains unchanged, and the distal end of the spring 120 may be provided to be connected to the snap member 10. Referring to FIG. 8, when the snap member 10 is in the snap position, the spring 120 is held in a compressed state by the restriction of the snap member 10, and the J-T slot sleeve 18 is in the first adjustment position. Referring to FIG. 9, when the snap member 10 is detached from the snap position, the restoring force (elastic force) of the spring 120 drives the pressing tube 17 to move toward the distal end, and further drives the J-T slot sleeve 18 to advance from the first adjustment position to the second adjustment position.

[0053] In one embodiment, as shown in FIGS. 3 and 8, the snap member 10 includes a positioning pin 102.

[0054] In one embodiment, referring to FIGS. 3, 5, 8, and 9, it further includes a slider 8 and a lever 9. The lever 9 is provided at the proximal end of the cryoablation needle, and the relative position with the vacuum wall is constant, which facilitates gripping. The slider 8 is connected to the proximal end of the pressing tube 17, and the slider 8 is directly or indirectly connected to the snap member 10. The slider 8, the pressing tube 17, and the J-T slot sleeve 18 can be controlled to move synchronously along the axial direction, thereby switching the distal end of the J-T slot sleeve 18 between adjustment positions. The slider 8 includes a guide tube 81, and the guide tube 81 is provided along the axial direction of the vacuum wall. A central fixing hole 83 is provided in the guide tube 81, and the distal end of the pressing tube 17 is fixed to the central fixing hole 83. A lever positioning groove 91 is provided in the lever 9, and a slider positioning groove 82 is provided in the slider 8. When the distal end of the J-T slot is in the first adjustment position, the positioning pin 102 is inserted into the lever positioning groove 91 and the slider positioning groove 82 at the same time, thereby making the relative position of the slider 8 with respect to the lever 9 constant, that is, maintaining the current prepurge mode. When it is necessary to switch to the freezing mode, it is only necessary to pull out the positioning pin 102 from the lever positioning groove 91 and the slider positioning groove 82.

[0055] In one embodiment, the slider 8 further includes an intake / return air guide hole 84 provided in the guide tube 81. Referring to FIG. 11, the intake pipe 6 and the return air pipe 7 pass through the intake / return air guide hole 84.

[0056] In a preferred embodiment, in order to facilitate the fixing and insertion / removal adjustment of the snap member, referring to FIG. 12, the snap member 10 further includes a gripping portion 101 and a C-shaped ring 103. Here, the gripping portion 101 and the positioning pin 102 are provided on the C-shaped ring 103, and the C-shaped ring 103 is covered on the outer wall of the lever 9, so that the radial detachment of the snap member can be prevented.

[0057] In another embodiment, when the lever 9 is not included, the C-shaped ring 103 is only covered on the outer wall with a fixed relative position to the vacuum wall, and the radial detachment of the snap member can also be prevented.

[0058] In a preferred embodiment, it further includes a spring stopper 27, and the relative position of the spring stopper 27 to the vacuum wall is constant. Referring to FIGS. 3 and 5, the distal end of the spring 120 is connected to the spring stopper 27, the proximal end of the spring 120 is connected to the guide tube 81 of the slider 8, and the spring drives the slider to further drive the pressing tube to move.

[0059] In a preferred embodiment, in order to improve the heat dissipation function, it further includes a finned tube 4, and the finned tube 4 is provided on the outer wall of the mandrel 3. The proximal end of the finned tube 4 is hermetically connected to the intake pipe 6, and the distal end of the finned tube 4 is hermetically connected to the proximal end of the J-T slot 1. Referring to FIG. 10, the proximal end of the J-T slot 1 is led from the intake slot 174 and inserted into the distal end of the finned tube 4 for hermetic connection.

[0060] In one embodiment, referring to FIGS. 3, 6, 9, and 12, the vacuum wall 2 further includes an outer tube 23. The distal end of the outer tube 23 is hermetically connected to the proximal end of the needle bar 21, and the proximal end of the outer tube 23 is hermetically connected to the proximal end of the inner tube 22.

[0061] In a preferred embodiment, in order to expand the internal volume of the proximal end of the inner tube, for example, the fin tube 4 may be pushed into the interior of the proximal end of the inner tube, or other more components may be accommodated. Since it is necessary to expand the internal volume of the proximal end of the inner tube, it is further necessary to expand the internal volume of the proximal end of the vacuum wall. The outer diameter of the outer tube 23 is larger than the outer diameter of the needle bar 21, the inner diameter of the outer tube 23 is larger than the inner diameter of the needle bar 21, and the distal end of the outer tube 23 is close to the needle tip 211 of the outer tube 23. side of end (Tip-side end) and the proximal end of the outer tube 23 is the end away from the needle tip 211 of the outer tube 23. (End on the side opposite to the tip) Furthermore, from the distal end to the proximal end of the inner tube 22, the inner tube 22 includes an inner tube front stage 221 and an inner tube rear stage 222 in sequence. The outer diameter of the inner tube rear stage 222 is larger than the outer diameter of the inner tube front stage 221, and the inner diameter of the inner tube rear stage 222 is larger than the inner diameter of the inner tube front stage 221. Referring to FIGS. 3, 5, 8, and 9, the inner tube front stage 221 is located inside the needle bar 21, the inner tube rear stage 222 is located inside the outer tube 23, and the dynamic seal point between the J-T slot sleeve and the J-T slot is provided on the inner tube rear stage 222.

[0062] In one embodiment, referring to FIGS. 3 and 5, it further includes a gasket 24. The gasket 24 is provided between the outer wall of the distal end of the inner tube 22 and the inner wall of the needle bar 21 to form a sealed connection.

[0063] In one embodiment, the J-T slot sleeve 18 includes a sleeve main portion 181, a sleeve seal portion 182, and a sleeve connection portion 183. Referring to FIGS. 4 and 6, from the distal end to the proximal end of the J-T slot, the sleeve main portion 181, the sleeve seal portion 182, and the sleeve connection portion 183 are sequentially distributed. The inner diameter of the sleeve main portion 181 is slightly larger than the outer diameter of the J-T slot 1. A seal gasket 19 is disposed between the sleeve seal portion 182 and the J-T slot 1. By radially pressing the sleeve seal portion 182, the gap between the J-T slot sleeve 18 and the J-T slot 1 forms a dynamic seal. The seal gasket 19 is preferably made of a PTFE material. The sleeve seal portion 182 is preferably disposed inside the distal end of the rear stage of the inner tube 222 to minimize the influence on the return air. The outer diameter of the sleeve connection portion 183 also becomes smaller due to radial pressing, and the sleeve connection portion 183 is inserted into and fixed to the pressing tube connection portion 175 of the pressing tube 17.

[0064] In another embodiment, the dynamic seal between the J-T slot sleeve 18 and the J-T slot 1 can also be achieved by a burr seal ring.

[0065] In a preferred embodiment, in order to better detect the freezing effect of the cryoablation needle, referring to FIGS. 3, 5, 8, and 9, it further includes a temperature measurement line 14. The distal end of the temperature measurement line 14 is a temperature measurement point 141, and the distal end of the temperature measurement line 14 is close to the needle tip 211 of the temperature measurement line 14 side of end (Tip-side end)It is as follows. The temperature measurement point 141 is provided at the distal end of the J-T slot sleeve 18 and is used to measure the temperature at the distal end of the J-T slot sleeve 18. When the distal end of the J-T slot sleeve 18 is located in the target area, the temperature measurement point 141 is used to monitor the temperature at the center of the tumor during cryo-rewarming. When the distal end of the J-T slot sleeve 18 is located within the vacuum insulation area, the temperature measurement point 141 is used to indicate whether the purge is being properly performed based on its temperature during the purge. The temperature measurement line 14 is led from the inside to the outside along the outside of the J-T slot sleeve 18, from inside the mandrel 3 or the pressing tube 17, and the inside of the mandrel 3 or the pressing tube 17 is sealed by filling it with an adhesive. Referring to FIG. 10, the temperature measurement line 14 may be led from the temperature measurement slot 173 into the inside of the pressing tube 17, and the inside of the pressing tube (the portion from the proximal end of the temperature measurement slot 173 to the proximal end of the pressing tube 17) is sealed by filling it with an adhesive. Preferably, it further includes a rewarming line, which is positioned and arranged in the same way as the temperature measurement line and is used to realize the rewarming function. Preferably, the temperature measurement line and / or the rewarming line employ T-type enamel thermocouple wires.

[0066] In one embodiment, referring to FIGS. 3, 5, 8, and 9, an outer sleeve 13 is further provided on the outer wall of the lever 9 to wrap parts such as the intake pipe and the return air pipe, making the appearance of the cryoablation needle cleaner and easier to operate.

[0067] In a preferred embodiment, the purge mode in which the distal end of the J-T slot sleeve is located in the vacuum insulation area 26 can be set to the factory shipment state of the product, and the operator can directly complete the purge of the product through the tool test process. After the tool test / purge is completed, it is adjusted to the freezing mode in which the distal end of the J-T slot sleeve is located in the target area 25. When freezing starts, since the ablation needle has performed the purge, the target area 25 is rapidly cooled to the lowest temperature.

[0068] In the description of this specification, terms such as "one embodiment", "one example", "specific implementation process", "example", etc. mean that the specific features, structures, materials, or characteristics described in relation to the said embodiment or exemplification are included in at least one embodiment or exemplification of the present invention. In this specification, the exemplary expressions of the above terms do not necessarily refer to the same embodiment or exemplification. Furthermore, the specific features, structures, materials, or characteristics described can be combined in an appropriate manner in any one or more embodiments or exemplifications.

[0069] Finally, it should be explained that each of the above-described embodiments is only for explaining the technical solution of the present invention and does not limit it. Although the present invention has been described in detail with reference to each of the above embodiments, as can be understood by those skilled in the art, the technical solutions described in each of the above embodiments can be changed, or some or all of their technical features can be equivalently replaced, and these changes and replacements do not deviate from the essence of the corresponding technical solutions from the scope of the technical solutions of each embodiment of the present invention.

Explanation of Reference Signs

[0070] 1-J-T slot; 2-Vacuum wall; 21-Needle rod; 211-Needle tip; 22-Inner tube; 221-Front section of inner tube; 222-Rear section of inner tube; 23-Outer tube; 24-Gasket; 25-Target area; 26-Vacuum insulation area; 27-Spring stopper; 28-Vacuum three-way tube; 281-Three-way tube connection part; 282-Three-way tube bypass; 291-Vacuum connection tube; 292-Vacuum hose; 293-Return air connection tube; 294-Shunt tube; 3-Mandrel; 4 - fin tube; 5 - seal assembly; 51 - seal ring; 52 - seal groove; 53 - seal pressing member; 6 - intake pipe; 7 - return air pipe; 8 - slider; 81 - guide tube; 82 - slider positioning groove; 83 - central fixing hole; 84 - guide hole for intake and return air pipes; 9 - lever; 91 - lever positioning groove; 10 - snap member; 101 - gripping part; 102 - positioning pin; 103 - C - type ring; 120 - spring; 13 - outer sleeve; 14 - temperature measurement line; 141 - temperature measurement point; 17 - pressing tube; 173 - temperature measurement slot; 174 - intake slot; 175 - pressing tube connection part; 18 - J - T slot sleeve; 181 - main part of the sleeve; 182 - sleeve sealing part; 183 - sleeve connection part; 19 - sealing gasket.

Claims

1. comprising a vacuum wall, a J-T slot and a J-T slot sleeve, wherein the vacuum wall comprises a needle bar and an inner tube, the distal end of the needle bar has a needle tip, the inner tube is bored through the needle bar, and a layer structure is formed between the inner tube and the needle bar, and the layer structure is a layer structure capable of forming a vacuum, the distal end of the inner tube has a first predetermined distance from the distal end of the needle bar along the axial direction of the vacuum wall, and the distal end of the inner tube is the end of the inner tube on the needle tip side, the J-T slot sleeve is fitted to the distal end of the J-T slot, and the distal end of the J-T slot is the end of the J-T slot on the needle tip side, the J-T slot and the J-T slot sleeve are bored through the inner tube, among the regions distributed along the axial direction of the vacuum wall, the region where the layer structure is located is a vacuum insulation region, and the region where the first predetermined distance is located is a target region, the distal end of the J-T slot is located in the vacuum insulation region, the J-T slot sleeve is movable relative to the J-T slot along the axial direction of the vacuum wall, and a dynamic seal is formed between the J-T slot sleeve and the J-T slot, the distal end of the J-T slot sleeve is switchable between at least two adjustment positions relative to the vacuum wall, and the at least two adjustment positions include a first adjustment position and a second adjustment position, the first adjustment position is within the target region, the second adjustment position is within the vacuum insulation region, when the distal end of the J-T slot sleeve is in the first adjustment position, the distal end of the J-T slot sleeve has a second predetermined distance from the needle tip along the axial direction of the vacuum wall, and the second predetermined distance is at least such that a frozen ice ball covers the needle tip, when the distal end of the J-T slot sleeve is in the second adjustment position, the distal end of the J-T slot sleeve has a third predetermined distance from the distal end of the vacuum insulation region along the axial direction of the vacuum wall, and the third predetermined distance is at least such that after the refrigerant is discharged from the J-T slot sleeve, it directly returns from within the vacuum insulation region, and the distal end of the vacuum insulation region is the end of the vacuum insulation region on the needle tip side, a cryoablation needle with a J-T slot sleeve, characterized in that.

2. Further comprising a J-T slot sleeve adjusting device, wherein the J-T slot sleeve adjusting device is used to switch the distal end of the J-T slot sleeve between two adjustment positions, namely the first adjustment position and the second adjustment position. The cryoablation needle with a J-T slot sleeve according to claim 1 is characterized in that.

3. The J-T slot sleeve adjusting device includes a pressing tube and a mandrel. The mandrel is provided along the axial direction of the vacuum wall. The pressing tube is perforated in the mandrel. The distal end of the pressing tube is connected to the proximal end of the J-T slot sleeve, and the distal end of the pressing tube is the end of the pressing tube on the needle tip side. The pressing tube and the J-T slot sleeve can be controlled to move synchronously along the axial direction, whereby the distal end of the J-T slot sleeve is switched between the first adjustment position and the second adjustment position. The cryoablation needle with a J-T slot sleeve according to claim 2 is characterized in that.

4. Further comprising a seal assembly, wherein the seal assembly is used to form a dynamic seal between the mandrel and the pressing tube. The cryoablation needle with a J-T slot sleeve according to claim 3 is characterized in that.

5. The seal assembly includes a seal ring, a seal groove and a seal pressing member. The seal groove is fixedly sealed with the proximal end of the mandrel. The seal ring is provided between the mandrel and the seal groove, and the seal pressing member is provided between the seal ring and the seal groove. The seal pressing member is controlled to be pressed in the radial direction, and further can press the mandrel against the seal ring in the radial direction, whereby a dynamic seal is formed between the mandrel and the pressing tube. The cryoablation needle with a J-T slot sleeve according to claim 4 is characterized in that.

6. Further comprising a spring and a snap member. One end of the spring can move synchronously with the distal end of the J-T slot sleeve and is also connected to the snap member. The snap member can enter and leave the snap position. The other end of the spring is fixed to the vacuum wall. When the snap member is in the snap position, the spring is held in a deformed state by the restriction of the snap member, and the distal end of the J-T slot sleeve is in the second adjustment position. The deformed state is a compressed state or an extended state. When the snap member is detached from the snap position, the spring is capable of generating a restoring force that returns from the deformed state to the natural state, and the restoring force is capable of driving the distal end of the J-T slot sleeve from the second adjustment position to the first adjustment position. The cryoablation needle with a J-T slot sleeve according to claim 4 is characterized by this.

7. The snap member includes a positioning pin and a C-ring. The positioning pin is provided on the C-ring. The C-ring is covered by an outer wall with a constant relative position to the vacuum wall. When the distal end of the J-T slot sleeve is in the first adjustment position, the positioning pin is used to hold the spring in the deformed state. The cryoablation needle with a J-T slot sleeve according to claim 6 is characterized by this.

8. It further includes a slider and a lever. The lever is provided at the proximal end of the vacuum wall, and the position of the lever relative to the vacuum wall is constant. The proximal end of the vacuum wall is the end on the side opposite to the needle tip of the vacuum wall. The slider is connected to the proximal end of the pressing tube and is further directly or indirectly connected to the snap member. The proximal end of the pressing tube is the end on the side opposite to the needle tip of the pressing tube. The slider, the pressing tube, and the J-T slot sleeve can be controlled to move synchronously along the axial direction, thereby switching the adjustment position of the distal end of the J-T slot sleeve. The lever is provided with a lever positioning groove, and the slider is provided with a slider positioning groove. The positioning pin is controlled to be inserted into the slider positioning groove and the lever positioning groove simultaneously, and it is further possible to keep the relative position of the slider relative to the lever and the vacuum wall constant. At this time, the distal end of the J-T slot sleeve is in the second adjustment position. The cryoablation needle with a J-T slot sleeve according to claim 7 is characterized by this.

9. The vacuum wall further includes an outer tube. The distal end of the outer tube is hermetically connected to the proximal end of the needle rod, the proximal end of the outer tube is hermetically connected to the proximal end of the inner tube, the distal end of the outer tube is the end of the outer tube on the needle tip side, and the proximal end of the outer tube is the end of the outer tube opposite to the needle tip. The outer diameter of the outer tube is larger than the outer diameter of the needle rod, and the inner diameter of the outer tube is larger than the inner diameter of the needle rod. From the distal end to the proximal end of the inner tube, the inner tube sequentially includes a front stage of the inner tube and a rear stage of the inner tube. The outer diameter of the rear stage of the inner tube is larger than the outer diameter of the front stage of the inner tube, and the inner diameter of the rear stage of the inner tube is larger than the inner diameter of the front stage of the inner tube. The front stage of the inner tube is bored through the needle rod, and the rear stage of the inner tube is bored through the outer tube. The cryoablation needle with a J-T slot sleeve according to claim 1 is characterized in that.

10. The dynamic seal point between the J-T slot sleeve and the J-T slot is located at the proximal end of the J-T slot sleeve. The cryoablation needle with a J-T slot sleeve according to claim 9 is characterized in that the dynamic seal point is located inside the rear stage of the inner tube.

11. Further comprising a temperature measurement line. The distal end of the temperature measurement line is a temperature measurement point, and the distal end of the temperature measurement line is the end of the temperature measurement line on the needle tip side. The temperature measurement point is provided at the distal end of the J-T slot sleeve and is used to measure the temperature at the distal end of the J-T slot sleeve. The cryoablation needle with a J-T slot sleeve according to any one of claims 1 to 10 is characterized in that.

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