Liquid cooling sealing system for ablation needle

Abstract

The ablation needle liquid cooling sealing system comprises a cooling liquid cavity and an ablation needle, a cavity baffle, a front cavity and a rear cavity are arranged in the cooling liquid cavity, and the front cavity and the rear cavity are located on the two sides of the cavity baffle respectively; one side, far away from the rear cavity, of the front cavity is provided with a cavity end cover which is hermetically connected with the front cavity, and one side, far away from the front cavity, of the rear cavity is provided with a radio frequency connector which is hermetically connected with the rear cavity; a pressure spacer bush is arranged between the part, located in the front cavity, of the cavity end cover and the cavity baffle, the two sides of the pressure spacer bush are connected with the part, located in the front cavity, of the cavity end cover and the cavity baffle in a sealed mode respectively, and the pressure spacer bush is communicated with the front cavity. The ablation needle comprises an outer needle rod and an inner needle rod coaxially arranged with the outer needle rod, the outer needle rod sequentially penetrates through the cavity end cover and the pressure spacer bush, the outer needle rod is communicated with the front cavity through the pressure spacer bush, and the inner needle rod penetrates through the outer needle rod and the cavity baffle and then is communicated with the rear cavity.

Description

[0001] This application is a divisional application of Chinese patent CN 202110954860.9, whose application date is August 19, 2021 and whose name is “A liquid-cooled sealing system for an ablation needle”. Technical Field

[0002] The present invention relates to the field of medical devices, and in particular to a liquid-cooled sealing system for an ablation needle. Background Art

[0003] The process of microwave energy coagulation inactivation of tumors is that polar molecules in the tissues move at high speed and generate heat by friction under the action of microwave field. When the temperature rises to above 60℃, the protein of tumor cells denatures and coagulates, leading to irreversible necrosis. The inactivated tumor tissue can produce heat shock protein, stimulate the body's immune system, improve the body's immune function, and inhibit the spread of tumor cells. It has the advantages of high thermal efficiency, fast heating speed, and uniform thermal field.

[0004] During the microwave ablation procedure, some of the heat from the ablation needle tip will be transferred to the needle shaft that is in contact with healthy tissue, causing unnecessary burns to the healthy tissue. Generally, cooling gas or liquid is circulated inside the needle shaft to complete the cooling process.

[0005] Existing liquid-cooled ablation needles use an integrated or partially disassembled cooling liquid chamber structure, which requires the use of a large amount of glue for bonding, which makes the process very complicated. In addition, during the assembly process, due to the defects of the glue bonding process, once bonded, it is inconvenient to adjust the position, and it is also difficult to avoid the need for reassembly due to human or objective errors, which leads to difficulties in the installation of the seal during the needle rod assembly process. Summary of the invention

[0006] In order to solve the above technical problems, the present invention provides a liquid-cooled sealing system for a liquid-cooled ablation needle, in which a sealing member is mounted on the outer surface of the needle rod, and the sealing member is squeezed by the spacer sleeve to achieve sealing between the needle rod surface and the cavity, thereby ensuring that the water inlet channel and the water return channel are isolated from each other.

[0007] The present invention provides an ablation needle liquid cooling sealing system, comprising a cooling liquid cavity and an ablation needle, wherein the cooling liquid cavity is provided with a cavity baffle and a front cavity and a rear cavity respectively located on both sides of the cavity baffle;

[0008] A cavity end cover sealedly connected to the front chamber is disposed on a side of the front chamber away from the rear chamber, and a radio frequency connector sealedly connected to the rear chamber is disposed on a side of the rear chamber away from the front chamber;

[0009] A pressure sleeve is provided between the portion of the cavity end cover located in the front chamber and the cavity baffle, and the two sides of the pressure sleeve are respectively sealed and connected to the portion of the cavity end cover located in the front chamber and the cavity baffle, and the pressure sleeve is in communication with the front chamber;

[0010] The ablation needle includes an outer needle rod and an inner needle rod coaxially arranged with the outer needle rod, the outer needle rod sequentially passes through the cavity end cover and the pressure sleeve, the outer needle rod is connected with the front chamber through the pressure sleeve, and the inner needle rod is connected with the rear chamber after passing through the outer needle rod and the cavity baffle.

[0011] In one embodiment, seals are provided between one side of the pressure sleeve and the portion of the cavity end cover located in the front chamber, and between the other side of the pressure sleeve and the cavity baffle, and these seals are squeezed in the axial direction of the front chamber through the cavity end cover, the pressure sleeve and the cavity baffle.

[0012] In one embodiment, a radial through hole is provided on the side wall of the pressure spacer, an outer cooling channel is formed between the inner wall of the outer needle rod and the outer wall of the inner needle rod, and the outer cooling channel is connected with the front chamber through the radial through hole.

[0013] In one embodiment, a seal is provided between the portion of the cavity end cover located in the front chamber and the front chamber inner wall of the front chamber, and is squeezed radially by the inner wall of the front chamber and the cavity end cover to seal the front chamber.

[0014] In one embodiment, a seal is provided between the portion of the RF connector located in the rear chamber and the rear chamber inner wall of the rear chamber, and is radially squeezed by the rear chamber inner wall and the portion of the RF connector located in the rear chamber to seal the rear chamber.

[0015] In one embodiment, an axial through hole for the inner needle rod to pass through is provided on the cavity baffle, and the axial through hole and the inner needle rod are clearance-matched, and the seal between the pressure spacer and the cavity baffle is compressed and deformed to seal the axial through hole and the inner needle rod.

[0016] In one embodiment, the diameter of the axial through hole is larger than the outer diameter of the outer needle rod, and the entire cooling liquid cavity or any part thereof can be removed from the front end of the outer needle rod.

[0017] In one embodiment, a cooling liquid inlet and a cooling liquid outlet are provided on the side of the cooling liquid cavity, the cooling liquid inlet passes through the cavity end cover and communicates with the front cavity, and the cooling liquid outlet passes through the cavity end cover and communicates with the rear cavity.

[0018] In one embodiment, a sealing member is provided inside the outer needle rod, which is located at the end of the outer needle rod away from the inner needle rod to seal the end of the outer needle rod away from the inner needle rod. A limiting sleeve is also provided inside the outer needle rod, and the limiting sleeve is used to ensure the fixed position and extrusion state of the sealing member.

[0019] In one embodiment, a transmission cable center tube is coaxially arranged inside the inner needle rod, and the transmission cable center tube passes through the inner needle rod and is connected to the RF connector. An inner cooling channel is formed between the outer wall of the transmission cable center tube and the inner wall of the inner needle rod, and the inner cooling channel is connected to the rear chamber.

[0020] Compared with the prior art, the ablation needle liquid cooling sealing system of the present invention has the following advantages:

[0021] 1. All the seals in the present invention can be installed outside the cavity, with large operating space, easy installation and convenient positioning; the connection and sealing of each chamber and channel are achieved through the seal, without using any adhesive, which is convenient for assembly or disassembly. Compared with the use of adhesive sealing, the compression seal of the seal can compensate for the slight shaking of the needle rod during use, and has higher sealing reliability; any part of the cavity can be removed from the front end of the needle rod, which provides a free operating space when welding the transmission cable and the RF connector, and facilitates the welding and installation of the RF connector.

[0022] 2. At least two seals are placed side by side in the outer needle rod and the fixed position and extrusion state of the seals are ensured by the fixing of the limit sleeve. The cooling circulation of the coolant is blocked at the seal and returns to the peristaltic pump along the inner cooling channel for circulation.

[0023] The above-mentioned technical features can be combined in various technically feasible ways to produce new embodiments, as long as the purpose of the present invention can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The invention will be described in more detail below based on non-limiting examples and with reference to the accompanying drawings, in which:

[0025] Figure 1 It shows the structure diagram of the ablation needle liquid cooling sealing system according to the present invention;

[0026] Figure 2 Shows Figure 1 Enlarged view of point A in the middle;

[0027] Figure 3 Shows Figure 1 Diagram of the coolant circulation system of the ablation needle liquid cooling sealing system;

[0028] Figure 4 Shows Figure 1 A diagram of the flow direction of the cooling liquid in the cooling liquid cavity of the ablation needle liquid cooling sealing system;

[0029] Figure 5 Shows Figure 1 Cooling liquid flow diagram at the inner and outer needle rod seals (A) in the liquid-cooled sealing system of the middle ablation needle.

[0030] In the figures, the same components are indicated by the same reference numerals. The figures are not drawn to scale.

[0031] Wherein, the accompanying drawings are marked as follows:

[0032] 1. Cavity end cover; 2. Cooling liquid cavity; 201. Front chamber inner wall; 202. Cavity baffle; 203. Rear chamber inner wall; 3. RF connector; 4. Outer needle rod; 5. Inner needle rod; 6. First seal; 7. Second seal; 8. Pressure spacer; 9. Third seal; 10. Fourth seal; 11. Transmission cable center tube; 12. Fifth seal; 13. Limiting sleeve; 1001. Front chamber; 1002. Rear chamber; 1003. External cooling channel; 1004. Internal cooling channel; 1005. Cooling liquid inlet; 1006. Cooling liquid outlet; 1007. Radial through hole; 1008. Axial through hole. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that, as long as there is no conflict, the various embodiments of the present invention and the various features in the embodiments can be combined with each other, and the technical solutions formed are all within the protection scope of the present invention.

[0034] Parts not described in the present invention can be implemented by adopting or drawing on existing technologies.

[0035] A first aspect of the present invention provides a liquid-cooled sealing system for an ablation needle, such as Figure 1 As shown, the liquid-cooled sealing system of the ablation needle of the present invention includes a cooling liquid cavity 2 which is axially sleeved on the outside of the ablation needle along the ablation needle, and the cooling liquid cavity 2 is divided into a front chamber 1001 and a rear chamber 1002 by a cavity baffle 202 which is radially arranged along the cooling liquid cavity 2; the front chamber 1001 is sealed by a cavity end cover 1, and a first sealing member 6 is arranged between the cavity end cover 1 and the front chamber inner wall 201, and the first sealing member 6 is radially squeezed by the front chamber inner wall 201 and the cavity end cover 1 to seal the front chamber 1001, and a pressure spacer 8 is arranged between the cavity end cover 1 and the cavity baffle 202, and the rear chamber 1002 is sealed by a radio frequency connector 3, and a second sealing member 7 is arranged between the rear chamber inner wall 203 and the radio frequency connector 3, and the second sealing member 7 is radially squeezed by the rear chamber inner wall 203 and the radio frequency connector 3 to seal the rear chamber.

[0036] A through hole is provided on the cavity end cover 1 for the outer needle rod 4 of the ablation needle to pass through. The outer needle rod 4 is inserted into the pressure spacer 8 through the cavity end cover 1. An inner needle rod 5 is coaxially arranged inside the outer needle rod 4. The inner needle rod 5 is connected to the rear chamber 1002 through the outer needle rod 4 and the cavity baffle 202. A transmission cable center tube 11 is also coaxially arranged inside the inner needle rod 5. The transmission cable center tube 11 is connected to the RF connector 3 through the inner needle rod 5.

[0037] All the seals in the present invention can be installed outside the cavity, with large operating space, easy installation and easy installation positioning; the communication and sealing of each chamber and channel are achieved through the seal, without using any adhesive, which is convenient for assembly or disassembly, and compared with the use of adhesive sealing, the compression seal of the seal can compensate for the slight shaking of the needle rod during use, and has higher sealing reliability; any component of the cavity can be removed from the front end of the needle rod, which provides a free operating space when welding the transmission cable and the RF connector, and facilitates the welding and installation of the RF connector.

[0038] In a specific embodiment, an outer cooling channel 1003 is formed between the inner wall of the outer needle rod 4 and the outer wall of the inner needle rod 5, a radial through hole 1007 is provided on the side wall of the pressure spacer 8, the outer cooling channel 1003 is connected to the front chamber 1001 through the radial through hole 1007, and an inner cooling channel 1004 is formed between the outer wall of the transmission cable center tube 11 and the inner wall of the inner needle rod 5, and the inner cooling channel 1004 is connected to the rear chamber 1002.

[0039] Furthermore, the cooling liquid cavity 2 is provided with a cooling liquid inlet 1005 communicating with the front chamber 1001 , and a cooling liquid outlet 1006 communicating with the rear chamber 1002 .

[0040] like Figure 1 and Figure 4 As shown, through the connection of the above structure, the corresponding connection between the coolant interface (coolant inlet 1005, coolant outlet 1006) and the cooling channel (external cooling channel 1003, internal cooling channel 1004) can be achieved. After the coolant interface is connected to the external coolant inlet and outlet device, the coolant cavity 2 can be used to circulate in the two cooling channels, thereby cooling the internal transmission cable. The connection and sealing of each chamber and channel are achieved through sealing parts, without the use of any adhesive, which is convenient for assembly and disassembly. Compared with the use of adhesive sealing, the compression sealing of the sealing part can compensate for the slight shaking of the needle bar during use, and has higher sealing reliability.

[0041] In a preferred embodiment, a third seal 9 is provided between the cavity end cover 1 and the pressure sleeve 8, and a fourth seal 10 is provided between the pressure sleeve 8 and the cavity baffle 202. The third seal 9 and the fourth seal 10 are squeezed in the axial direction of the front chamber 1001 through the cavity end cover 1, the pressure sleeve 8 and the cavity baffle 202.

[0042] The third seal 9 is sleeved on the outside of the outer needle rod 4, and the third seal 9 is deformed under pressure to seal the cavity end cover 1, thereby completing the sealing of the cavity end cover 1 and the outer needle rod 4; the fourth seal 10 is sleeved on the outside of the inner needle rod 5, and the fourth seal 10 is deformed under pressure to seal the inner needle rod 5 and the axial through hole 1008, thereby sealing the rear chamber 1002.

[0043] Specifically, the cavity end cover 1 is pressed against the front chamber 1001 under the action of external force, and the pressing force is transmitted to the pressure sleeve 8 and the cavity baffle 202, thereby squeezing the third seal 9 and the fourth seal 10 in the axial direction, and at the same time, the first seal 6 is squeezed radially by the front chamber inner wall 201 and the cavity end cover 1, and the compression and deformation of the first seal 6, the third seal 9 and the fourth seal 10 completes the sealing of the front chamber 1001, and at the same time, the compression and deformation of the third seal 9 completes the sealing of the outer needle rod 4, and the compression and deformation of the fourth seal 10 completes the sealing of the inner needle rod 5.

[0044] The RF connector 3 is pressed against the rear chamber 1002 under the action of external force, and the second seal 7 is squeezed radially by the rear chamber inner wall 203 and the RF connector 3 . The compression and deformation of the second seal 7 and the fourth seal 10 complete the sealing of the rear chamber 1002 .

[0045] In a preferred embodiment, the cavity baffle 202 is provided with an axial through hole 1008 for the inner needle rod 5 to pass through, the diameter of the axial through hole 1008 is larger than the outer diameter of the outer needle rod 4, and the axial through hole 1008 and the inner needle rod 5 are in clearance fit. When the fourth seal 10 is deformed under pressure, it can seal the axial through hole 1008 and the inner needle rod 5. The diameter of the axial through hole 1008 is larger than the outer diameter of the outer needle rod 4, and when the transmission cable center tube 11 and the RF connector 3 are connected or welded, the cooling liquid cavity 2 as a whole or any part can be moved out from the front end of the outer needle rod 4, that is, away from the end in the direction of the front chamber.

[0046] The entirety or any part of the cooling liquid cavity 2 can be removed from the front end of the needle rod, providing a free operating space for the connection or welding between the transmission cable center tube 11 and the RF connector 3, and facilitating the welding and installation of the RF connector 3.

[0047] In an optional embodiment, if Figure 2As shown, a fifth seal 12 is provided in the outer needle rod 4. The fifth seal 12 is provided at one end of the outer needle rod 4 away from the inner needle rod 5 and is fixed by a limiting sleeve 13. The end of the outer needle rod 4 away from the inner needle rod 5 is sealed by the fifth seal 12. Preferably, at least two fifth seals 12 are provided in the outer needle rod 4, and at least two fifth seals 12 are distributed side by side along the length direction of the outer needle rod 4. Two or more fifth seals 12 are arranged side by side in the outer needle rod 4 and fixed by a limiting sleeve 13, so as to ensure the fixed position and extrusion state of the fifth seal 12. The coolant is as follows Figure 5 The flow direction shown performs a cooling cycle, is blocked at the fifth seal 12 and returns to the peristaltic pump along the inner cooling channel 1004 for circulation.

[0048] Specifically, Figure 1 , Figure 3 and Figure 5 As shown, the coolant enters the front chamber 1001 through the coolant inlet 1005 and then enters the outer cooling channel 1003 through the through hole on the pressure spacer 8. The coolant flows along the outer cooling channel 1003 and is intercepted at the fifth seal 12 in the outer needle rod 4. The coolant flows back into the inner cooling channel 1004. The coolant flows along the inner cooling channel 1004 to the rear chamber 1002 and then flows out along the coolant outlet 1006 to the water outlet pipe (refer to Figure 3 ) and then returns to the external coolant, and the cycle is repeated.

[0049] In a preferred embodiment, a first groove for accommodating a first seal 6 is provided on the cavity end cover 1, and a second groove for accommodating a second seal 7 is provided on the RF connector 3. The first seal 6 is squeezed in the radial direction of the front chamber 1001 by the cavity end cover 1 and the front chamber inner wall 201, and the second seal 7 is squeezed in the radial direction of the rear chamber 1002 by the rear chamber inner wall 203 and the RF connector 3.

[0050] In a specific embodiment, the cavity end cover 1 is formed with a first groove along its circumference to accommodate the first seal 6. The first seal 6 is sleeved on the cavity end cover 1. The first seal 6 is squeezed in the radial direction of the front chamber 1001 through the cavity end cover 1 and the front chamber inner wall 201.

[0051] The RF connector 3 is formed with a second groove along its circumference to accommodate the second seal 7 . The second seal 7 is sleeved on the RF connector 3 . The second seal 7 is squeezed by the rear chamber inner wall 203 and the RF connector 3 in the radial direction of the rear chamber 1002 .

[0052] Each sealing member can preferably be a sealing ring.

[0053] In a more preferred embodiment, the cavity baffle 202 and the inner wall of the cooling liquid cavity 2 are an integrally formed structure.

[0054] Unless otherwise defined, the technical or scientific terms used in the present invention shall have the common meanings understood by persons with ordinary skills in the field to which the present invention belongs. "Include" or "comprising" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0055] At this point, it should be appreciated by those skilled in the art that, although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A liquid-cooled sealing system for an ablation needle, characterized in that: It comprises a cooling liquid cavity (2), wherein the cooling liquid cavity (2) is provided with a cavity baffle (202) and a front cavity (1001) and a rear cavity (1002) respectively located on both sides of the cavity baffle (202); A cavity end cover (1) sealedly connected to the front chamber (1001) is provided on a side of the front chamber (1001) away from the rear chamber (1002), and a radio frequency connector (3) sealedly connected to the rear chamber (1002) is provided on a side of the rear chamber (1002) away from the front chamber (1001); A pressure sleeve (8) is provided between the portion of the cavity end cover (1) located in the front chamber (1001) and the cavity baffle (202), and two sides of the pressure sleeve (8) are respectively sealedly connected to the portion of the cavity end cover (1) located in the front chamber (1001) and the cavity baffle (202), and the pressure sleeve (8) is in communication with the front chamber (1001); The ablation needle comprises an outer needle rod (4) and an inner needle rod (5) coaxially arranged with the outer needle rod (4); the outer needle rod (4) sequentially passes through the cavity end cover (1) and the pressure sleeve (8); the outer needle rod (4) is connected to the front chamber (1001) through the pressure sleeve (8); and the inner needle rod (5) passes through the outer needle rod (4) and the cavity baffle (202) and then communicates with the rear chamber (1002).

2. The ablation needle liquid cooling sealing system according to claim 1, characterized in that: Seals are provided between one side of the pressure sleeve (8) and the portion of the cavity end cover (1) located in the front chamber (1001), and between the other side of the pressure sleeve (8) and the cavity baffle (202), and these seals are squeezed in the axial direction of the front chamber (1001) through the cavity end cover (1), the pressure sleeve (8) and the cavity baffle (202).

3. The ablation needle liquid cooling sealing system according to claim 1 or 2, characterized in that: A radial through hole (1007) is provided on the side wall of the pressure spacer (8), and an external cooling channel (1003) is formed between the inner wall of the outer needle rod (4) and the outer wall of the inner needle rod (5), and the external cooling channel (1003) is connected to the front chamber (1001) through the radial through hole (1007).

4. The ablation needle liquid cooling sealing system according to claim 1 or 2, characterized in that: A sealing member is provided between the portion of the cavity end cover (1) located in the front chamber (1001) and the front chamber inner wall (201) of the front chamber (1001), and the sealing member is squeezed in the radial direction by the inner wall of the front chamber (1001) and the cavity end cover (1) to seal the front chamber (1001).

5. The ablation needle liquid cooling sealing system according to claim 1 or 2, characterized in that: A sealing member (7) is provided between the portion of the RF connector (3) located in the rear chamber (1002) and the rear chamber inner wall (203) of the rear chamber (1002), and is squeezed in the radial direction by the rear chamber inner wall (203) and the portion of the RF connector (3) located in the rear chamber (1002) to seal the rear chamber (1002).

6. The ablation needle liquid cooling sealing system according to claim 1 or 2, characterized in that: The cavity baffle (202) is provided with an axial through hole (1008) for the inner needle rod (5) to pass through, and the axial through hole (1008) and the inner needle rod (5) are clearance-matched, and the seal between the pressure spacer (8) and the cavity baffle (202) is compressed and deformed to seal the axial through hole (1008) and the inner needle rod (5).

7. The ablation needle liquid cooling sealing system according to claim 6, characterized in that: The diameter of the axial through hole (1008) is greater than the outer diameter of the outer needle rod (4), and the entire cooling liquid cavity (2) or any part thereof can be removed from the front end of the outer needle rod (4).

8. The ablation needle liquid cooling sealing system according to claim 1 or 2, characterized in that: A cooling liquid inlet (1005) and a cooling liquid outlet (1006) are provided on the side of the cooling liquid cavity (2); the cooling liquid inlet (1005) passes through the cavity end cover (1) and is connected to the front chamber (1001); and the cooling liquid outlet (1006) passes through the cavity end cover (1) and is connected to the rear chamber (1002).

9. The ablation needle liquid cooling sealing system according to claim 1 or 2, characterized in that: A sealing member is provided inside the outer needle rod (4), which is located at the end of the outer needle rod (4) away from the inner needle rod (5) to seal the end of the outer needle rod (4) away from the inner needle rod (5). A limiting sleeve (13) is also provided inside the outer needle rod (4), and the limiting sleeve (13) is used to ensure the fixed position and extrusion state of the sealing member.

10. The ablation needle liquid cooling sealing system according to claim 1 or 2, characterized in that: A transmission cable center tube (11) is also coaxially arranged inside the inner needle rod (5), and the transmission cable center tube (11) passes through the inner needle rod (5) and is connected to the radio frequency connector (3). An inner cooling channel (1004) is formed between the outer wall of the transmission cable center tube (11) and the inner wall of the inner needle rod (5), and the inner cooling channel (1004) is connected to the rear chamber (1002).

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