Steam ablation heating module and ablation catheter applying same

Abstract

The invention discloses a steam ablation heating module and an ablation catheter applying the same, and relates to the technical field of medical instruments.The heating module comprises a litz coil assembly and a heating pipe assembly, and the litz coil assembly comprises a litz coil; the heating pipe assembly comprises a spiral heating pipe, the spiral heating pipe is located on the inner side of the Litz coil, a gap is formed between the spiral heating pipe and the Litz coil, the spiral heating pipe and the Litz coil are coaxially arranged, the spiral heating pipe is heated through the induction heating principle of the Litz coil, water in the spiral heating pipe is converted into water vapor, and the water vapor is heated through the spiral heating pipe. The spiral heating pipe and the Litz coil achieve non-contact induction heating, medium interference can be reduced, the spiral heating pipe and the Litz coil are coaxially arranged, the gap between the spiral heating pipe and the Litz coil is uniform, and an air medium in the middle is uniform, so that water in the spiral heating pipe is heated uniformly and stably, and the continuous, stable and constant-temperature steam outlet effect is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and particularly relates to a steam ablation heating module and an ablation catheter applying the same. Background Art

[0002] Prostatic thermal steam ablation is a new minimally invasive technique combined with endoscopic intervention. This technique directly injects high-temperature water vapor into the prostate tissue through a catheter. By using the latent heat release of the water vapor, the tissue temperature rapidly rises, causing the tissue cells in the hyperplastic (lesioned) area of the prostate to die instantly, forming a spherical necrosis area, and the necrosis area is eliminated and repaired through the body's own metabolism, achieving the purpose of reducing the prostate. Compared with other methods, this method does not require implanting foreign objects and can produce a long-term therapeutic effect.

[0003] The heating module that generates steam in the catheter is particularly important, directly affecting the temperature accuracy, continuity, and stability of the steam output. Existing prostatic thermal steam ablation techniques use heating wires, which will be affected by metal (such as copper, iron, or aluminum, etc.) media, sharing part of the heating energy, reducing the conversion rate, resulting in large temperature fluctuations and low stability. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a steam ablation heating module. The heating module includes a Litz coil assembly and a heating tube assembly. The Litz coil assembly includes a Litz coil. The heating tube assembly includes a spiral heating tube. The spiral heating tube is located inside the Litz coil. There is a gap between the spiral heating tube and the Litz coil, and the spiral heating tube is coaxially arranged with the Litz coil.

[0005] Preferably: The number of turns of the Litz coil is greater than the number of turns of the spiral of the spiral heating tube.

[0006] Preferably: The spiral heating tube includes a spiral coil end, and a row of welding points is welded on each of the two opposite sides of the spiral coil end.

[0007] Preferably: The spiral coil end is composed of a plurality of spiral coils connected together, and adjacent two spiral coils are fixed by laser spot welding.

[0008] Preferably: The spiral heating tube further includes a water inlet end and a water outlet end; The water inlet end is communicated with the spiral coil of one side end of the spiral coil end, The water outlet end is communicated with the spiral coil of the other side end of the spiral coil end. A first temperature detection point is arranged on the tube wall of the water outlet end, and the first temperature detection point is welded with a thermocouple wire.

[0009] Preferably, a second temperature detection point is provided on the tube wall at the end of the spiral coil. The second temperature detection point is located on the inner wall of the spiral coil where the end of the spiral coil is connected to the water outlet end, and a thermocouple wire is welded at the second temperature detection point.

[0010] Preferably, the litz coil assembly further includes a gold finger cylinder and a gold finger fixing seat. The gold finger cylinder is installed on the gold finger fixing seat, and the length of the gold finger cylinder is greater than the length of the litz coil.

[0011] Preferably, the gold finger cylinder is made of PI polyimide high-temperature resistant material.

[0012] An ablation catheter includes a handle housing and at least one of the above-mentioned heating modules, and the heating module is installed in the handle housing.

[0013] Preferably, when entering the preparation stage, the heating module is preheated to 80°C ± 1°C; When entering the treatment working mode, the heating module is heated to 103°C ± 2°C and outputs the steam required for work.

[0014] The technical effects and advantages of the present invention: 1. In the present invention, the spiral heating tube and the litz coil achieve non-contact induction heating, which can reduce medium interference.

[0015] 2. In the present invention, the spiral heating tube and the litz coil are coaxially arranged, and the gap between them is uniform, and the air medium in the middle is uniform, so that the water in the spiral heating tube is heated evenly and stably, achieving a continuous and stable steam output effect with a constant temperature.

[0016] 3. In the present invention, the litz coil can completely cover the spiral heating tube axially, and the spiral coils at both ends of the spiral heating tube are located inside the litz coil, so that the induction heating area is fully covered.

[0017] 4. In the present invention, a row of welding points is welded on each of the opposite sides of the end of the spiral coil, which improves the strength of the end of the spiral coil, and the spiral heating tube will not deform during the heating process.

[0018] 5. In the present invention, the highest temperature and the steam output temperature in the spiral heating tube are collected. In the preheating stage: the main control board of the device dynamically adjusts the duty cycle through the PID algorithm to accurately control the temperature to 80°C ± 1°C; in the ablation (treatment) stage: the main control board of the device switches to the constant power output mode. Based on the constant characteristic of the induction heating conversion rate of the litz coil, this mode can stabilize the temperature at 103°C ± 2°C and maintain the required steam output temperature, thereby significantly improving the temperature accuracy, continuity and stability of the output steam. Description of the Drawings

[0019] Figure 1 It is a schematic structural diagram of the steam ablation heating module provided by the embodiment of the present application; Figure 2 It is a schematic structural diagram of a litz coil assembly and a heating tube assembly in a steam ablation heating module provided by an embodiment of the present application; Figure 3 It is a schematic installation structure diagram of a litz coil and a spiral heating tube in a steam ablation heating module provided by an embodiment of the present application; Figure 4 It is a schematic diagram of the temperature measurement points of a spiral heating tube in a steam ablation heating module provided by an embodiment of the present application; Figure 5 It is a schematic structural diagram of a spiral heating tube in a steam ablation heating module provided by an embodiment of the present application; Figure 6 It is in the steam ablation heating module provided by an embodiment of the present application Figure 4 A schematic enlarged view of the structure at A; Figure 7 It is a schematic structural diagram of a gold finger fixing seat in a steam ablation heating module provided by an embodiment of the present application; Figure 8 It is a schematic structural diagram of an ablation catheter provided by an embodiment of the present application; Figure 9 It is in the ablation catheter provided by an embodiment of the present application Figure 8 A schematic enlarged view of the structure at B; Figure 10 It is a schematic structural diagram of a steam ablation heating module provided by another embodiment of the present application.

[0020] In the figure: 100, handle housing; 200, heating module; 210, litz coil assembly; 211, litz coil; 212, gold finger cylinder; 213, gold finger fixing seat; 2131, bottom plate; 2132, screw hole; 2133, first support; 2134, second support; 2135, support protrusion; 2136, card slot; 220, heating tube assembly; 221, spiral heating tube; 2211, spiral coil end; 2212, water inlet end; 2213, water outlet end; 2214, first temperature detection point; 2215, second temperature detection point; 2216, welding point; 222, water pipe; 300, water pipe bracket; 310, slot. Detailed implementation manners

[0021] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. The embodiments of the present invention are given for the purpose of illustration and description, and are not exhaustive or limit the present invention to the disclosed form. Many modifications and variations will be apparent to those of ordinary skill in the art. The embodiments are selected and described to better illustrate the principles and practical applications of the present invention, and enable those of ordinary skill in the art to understand the present invention and thus design various embodiments with various modifications suitable for specific purposes.

[0022] Please refer to Figures 1 to 3 As shown, in this embodiment, a steam ablation heating module is provided. The heating module 200 includes a litz coil assembly 210 and a heating tube assembly 220. The litz coil assembly 210 includes a litz coil 211. The heating tube assembly 220 includes a spiral heating tube 221. The spiral heating tube 221 is located inside the litz coil 211. There is a gap between the spiral heating tube 221 and the litz coil 211, and the spiral heating tube 221 and the litz coil 211 are coaxially arranged.

[0023] Through the principle of inductive heating of the litz coil 211, the spiral heating tube 221 is heated, so that the water inside the spiral heating tube 221 is converted into water vapor. The spiral heating tube 221 and the litz coil 211 achieve non-contact inductive heating, which can reduce medium interference. And the spiral heating tube 221 and the litz coil 211 are coaxially arranged, and the gap between the two is uniform, and the air medium in the middle is uniform, so that the water in the spiral heating tube 221 is heated evenly and stably, achieving a continuous and stable steam output effect with a constant temperature.

[0024] When in use, it is used in conjunction with the equipment. The heating module is preheated to 80°C ± 1°C to enter the preparation stage. When it is necessary to enter the treatment working mode, the main control board gives the corresponding power and instantaneously heats to output the steam required for work, and the temperature range is 103°C ± 2°C.

[0025] In a specific embodiment, the central axes of the spiral heating tube 221 and the litz coil 211 coincide in the horizontal direction. The distance between the outer wall of the spiral heating tube 221 and the inner wall of the litz coil 211 is D, and the value range of D is 0.4 - 0.6 mm, which can achieve a better inductive heating effect.

[0026] Furthermore, the number of turns of the litz coil 211 is greater than the number of turns of the spiral of the spiral heating tube 221. The litz coil 211 can completely cover the spiral heating tube 221 axially. The spiral turns at both ends of the spiral heating tube 221 are located inside the litz coil 211, and the inductive heating area is fully covered.

[0027] In a specific embodiment, the number of turns of the Litz coil 211 is 28, the number of turns of the spiral heating tube 221 is 24, the spiral heating tube 221 is placed inside the Litz coil 211, and each end of the Litz coil 211 has 2 more turns than the spiral heating tube 221, so that the spiral turns at both ends of the spiral heating tube 221 are located inside the Litz coil 211, and the spiral turns of the spiral heating tube 221 are located inside the Litz coil 211 in the length direction.

[0028] In other embodiments, the number of turns of the Litz coil 211 can be 30, 32 or 34, the number of turns of the spiral heating tube 221 can be 26, 28 or 30, and each end of the Litz coil 211 has at least 2 more turns than the spiral heating tube 221, so that the spiral turns at both ends of the spiral heating tube 221 are located inside the Litz coil 211.

[0029] Refer to Figures 4 to 6 As shown, the spiral heating tube 221 includes a spiral coil end 2211, a water inlet end 2212 and a water outlet end 2213. The spiral coil end 2211 is composed of a plurality of spiral coils connected together and is in the shape of a hollow cylinder. The spiral coils are closely attached to each other. The water inlet end 2212 is communicated with the spiral coil at one side end of the spiral coil end 2211, and the water outlet end 2213 is communicated with the spiral coil at the other side end of the spiral coil end 2211. Both the water inlet end 2212 and the water outlet end 2213 are straight pipes.

[0030] Furthermore, the spiral heating tube 221 is made of Inconel (Inconel alloy).

[0031] Furthermore, the length of the water inlet end 2212 is shorter, and the length of the water outlet end 2213 is longer.

[0032] The water temperature at the water outlet end 2213 is much higher than that at the water inlet end 2212. After the metal pipe is heated, it will expand significantly. The longer water outlet end can provide sufficient length buffer to avoid pipe deformation, weld cracking or spiral structure distortion caused by thermal stress. At the same time, the temperature change at the water inlet end 2212 is small and the expansion amount is limited. Therefore, the straight pipe can be designed shorter.

[0033] It can also achieve fluid stability and pressure release: reduce the risk of turbulence and cavitation: The heated water may generate steam bubbles or local vaporization (especially in a high pressure difference environment). The longer water outlet straight pipe can reduce the flow rate, allowing more time for the bubbles to re-condense or distribute evenly, and avoiding the impact damage of cavitation on the pipe wall.

[0034] Smoothing of the pressure gradient: The volume expansion of high-temperature water may cause pressure fluctuations. The long straight pipe can act as a "buffer section" to gradually stabilize the pressure through frictional resistance, preventing water hammer effect or sudden system pressure changes.

[0035] Optimization of Heat Exchange Efficiency: Prolonging the Retention Time of High-Temperature Water If the straight outlet pipe is too short, the high-temperature water will quickly leave the system, which may cause insufficient heat transfer to the external load (such as for secondary heat exchange). Appropriately prolonging the straight pipe can increase the efficiency of waste heat utilization.

[0036] Avoiding Cold Water "Stealing Heat": If the straight inlet pipe is too long, the cold water may absorb the waste heat of the pipe wall before entering the spiral section, reducing the effective temperature difference in the spiral section. Therefore, shortening the straight inlet pipe can ensure that the heating of the cold water is concentrated in the spiral section.

[0037] Material Characteristics and Safety Redundancy: High-Temperature Strength Decay Although Inconel alloy maintains its strength at high temperatures, changes may still occur during long-term operation. A longer straight outlet pipe can disperse the stress concentration points and reduce the risk of local fatigue.

[0038] Furthermore, a row of welding points is welded on each of the opposite sides of the spiral coil end 2211 to reduce the deformation of the spiral coil end 2211 at high temperatures, control the uneven gap caused by the deformation, and improve the stability of the induction heating of the Litz coil 211.

[0039] Specifically, adjacent two spiral coils are fixed by laser spot welding to form a welding point 2216 between the two spiral coils. The welding point 2216 is located in the depression between adjacent spiral coils. The distance from the outer wall of the welding point 2216 to the axis of the spiral heating tube 221 is less than the distance from the outer wall of the spiral coil to the axis of the spiral heating tube 221, so that the welding point 2216 is located in the depression between adjacent spiral coils and does not protrude from the outer surface of the spiral heating tube 221, thereby improving the strength of the spiral heating tube 221 and preventing it from deforming during the heating process.

[0040] Furthermore, a first temperature detection point 2214 is provided on the pipe wall of the outlet end 2213 and welded to the thermocouple wire for real-time detection of the steam temperature.

[0041] Furthermore, a second temperature detection point 2215 is provided on the pipe wall of the spiral coil end 2211, and the second temperature detection point 2215 is the highest temperature point inside the spiral coil end 2211.

[0042] Specifically, the second temperature detection point 2215 is located on the inner wall of the spiral coil where the spiral coil end 2211 is connected to the outlet end 2213 and welded to the thermocouple wire for real-time detection of the highest temperature inside the spiral coil end 2211.

[0043] Collecting the highest temperature inside the spiral heating tube 221 and the steam outlet temperature, and used in conjunction with equipment: 1. Preheating stage: The main control board of the device dynamically adjusts the duty cycle through the PID algorithm to accurately control the temperature to 80°C ± 1°C.

[0044] 2. Ablation (treatment) stage: The main control board of the device switches to a constant power output mode. Based on the characteristic of the constant induction heating conversion rate of the Litz coil, this mode can stabilize the temperature at 103°C ± 2°C and maintain the required steam output temperature, thus significantly improving the temperature accuracy, continuity, and stability of the output steam.

[0045] Furthermore, the Litz coil assembly 210 further includes a gold finger cylinder 212 and a gold finger fixing base 213. The gold finger cylinder 212 is installed on the gold finger fixing base 213. The gold finger cylinder 212 is a hollow cylinder. The Litz coil 211 is wound around the outside of the gold finger cylinder 212. The length of the gold finger cylinder 212 is greater than the length of the Litz coil 211. The spiral heating tube 221 is located inside the gold finger cylinder 212.

[0046] Furthermore, the gold finger cylinder 212 is made of PI polyimide high-temperature resistant material. Preferably, PI polyimide tape is used, which can withstand a temperature of 300 degrees. The gold finger cylinder 212 is used to isolate the spiral heating tube 221 to prevent the spiral heating tube 221 from overheating and burning out other components.

[0047] Refer to Figure 7 As shown, in a specific embodiment, the gold finger fixing base 213 includes a bottom plate 2131 and a plurality of support members fixed to the upper end of the bottom plate 2131. A screw hole 2132 is provided at one side end of the bottom plate 2131 to facilitate fixing the bottom plate 2131 with screws.

[0048] Furthermore, the plurality of support members includes at least a first support member 2133 and two second support members 2134. The first support member 2133 is located in the middle of the bottom plate 2131, and an arc-shaped groove is provided at the upper end of the first support member 2133 for supporting the Litz coil 211.

[0049] Furthermore, the two second support members 2134 are located at both ends of the bottom plate 2131. A support protrusion 2135 is provided at the end of the second support member 2134 close to each other. The support protrusion 2135 is integrally arc-shaped. There are two support protrusions 2135. A card slot 2136 is provided between the two support protrusions 2135. The card slot 2136 is used to accommodate the water inlet end 2212 or the water outlet end 2213 to avoid affecting the installation of the heating tube assembly 220.

[0050] Specifically, the cylindrical structure formed by the arc-shaped groove on the first support member 2133 is coaxial with the cylindrical structure formed by the support protrusion 2135.

[0051] Refer to Figures 8 to 9As shown, in this embodiment, an ablation catheter is provided for use in prostate thermal steam ablation. It includes a handle housing 100, a catheter, and a heating module 200. The heating module 200 is installed within the handle housing 100. Specifically, the gold finger holder 213 is fixed within the handle housing 100 by screws.

[0052] The heating module 200 instantaneously raises the temperature of liquid water to convert it into gaseous state to form high-temperature water vapor, and the high-temperature water vapor is directly injected into the prostate tissue through the catheter. The catheter is a prior art and will not be elaborated here.

[0053] The ablation catheter equipped with this heating module 200 has high temperature accuracy, good continuity, and high stability in steam output.

[0054] During installation, the spiral heating tube 221 is placed within the gold finger cylinder 212. The water inlet end 2212 and the water outlet end 2213 protrude from both ends of the gold finger cylinder 212. The water inlet end 2212 and the water outlet end 2213 are connected to an external water pipe 222. Then, the litz wire coil 211 is placed on the first support member 2133. Both ends of the gold finger cylinder 212 are sleeved and bonded to the outer wall of the support protrusion 2135 to complete the installation of the litz wire coil 211. Then, the water pipe 222 is fixed to the water pipe bracket 300. The spiral heating tube 221 and the litz wire coil 211 are coaxial and there is a gap between them.

[0055] Furthermore, a slot 310 is provided on the water pipe bracket 300, and the water pipe 222 is snap-fitted into the slot 310, thereby fixing the spiral heating tube 221.

[0056] Refer to Figure 10 As shown, in another embodiment, two heating modules 200 can also be provided. Both heating modules 200 are installed within the handle housing 100. One heating module 200 is used for preheating, and the preheating temperature range is 80°C ± 1°C. The other heating module 200 is used for steam output, and the steam output temperature range is 103°C ± 2°C.

[0057] During use, when the two heating modules 200 are in use, they cooperate with the device. One heating module 200 is heated to 80°C ± 1°C to enter the preparation stage. When it is necessary to enter the treatment working mode, the main control board gives the corresponding power to instantaneously heat the other heating module 200 to output the steam required for work at 103°C ± 2°C, shortening the ramp-up time of the finally output steam, enabling the liquid water to be instantaneously heated to the gaseous state and reducing the waiting time.

[0058] Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art and related fields based on the embodiments of the present invention without creative efforts shall fall within the scope of protection of the present invention. The structures, devices, and operation methods not specifically described and explained in the present invention shall be implemented by conventional means in the art unless otherwise specified and limited.

Claims

1. A steam ablation heating module, characterized in that, The heating module (200) includes a Litz coil assembly (210) and a heating tube assembly (220), and the Litz coil assembly (210) includes a Litz coil (211). The heating tube assembly (220) includes a spiral heating tube (221). The spiral heating tube (221) is located inside the Litz coil (211). There is a gap between the spiral heating tube (221) and the Litz coil (211), and the spiral heating tube (221) is coaxially arranged with the Litz coil (211).

2. The steam ablation heating module according to claim 1, characterized in that, The number of turns of the Litz coil (211) is greater than the number of turns of the spiral of the spiral heating tube (221).

3. The steam ablation heating module according to claim 1, wherein, The spiral heating tube (221) includes a spiral coil end (2211). A row of welding points is welded on each of the two opposite sides of the spiral coil end (2211).

4. The steam ablation heating module according to claim 3, wherein The spiral coil end (2211) is composed of a plurality of spiral coils connected together, and adjacent two spiral coils are fixed by laser spot welding.

5. A steam ablation heating module according to claim 1, characterized in that, The spiral heating tube (221) further includes a water inlet end (2212) and a water outlet end (2213). The water inlet end (2212) communicates with the spiral coil at one side end of the spiral coil end (2211). The water outlet end (2213) communicates with the spiral coil at the other side end of the spiral coil end (2211). A first temperature detection point (2214) is arranged on the tube wall of the water outlet end (2213), and the first temperature detection point (2214) is welded to a thermocouple wire.

6. The steam ablation heating module according to claim 5, wherein A second temperature detection point (2215) is arranged on the tube wall of the spiral coil end (2211). The second temperature detection point (2215) is located on the inner wall of the spiral coil where the spiral coil end (2211) is connected to the water outlet end (2213), and the second temperature detection point (2215) is welded to a thermocouple wire.

7. A steam ablation heating module according to claim 1, wherein, The Litz coil assembly (210) further includes a gold finger cylinder (212) and a gold finger fixing seat (213). The gold finger cylinder (212) is installed on the gold finger fixing seat (213), and the length of the gold finger cylinder (212) is greater than the length of the Litz coil (211).

8. A steam ablation heating module according to claim 7, characterized in that, The gold finger cylinder (212) is made of PI polyimide high-temperature resistant material.

9. An ablation catheter, characterized in that, It includes a handle housing (100) and at least one heating module (200) according to any one of claims 1-8. The heating module (200) is installed inside the handle housing (100).

10. An ablation catheter, characterized in that, When entering the preparation stage, the heating module (200) is preheated to 80°C ± 1°C. When entering the treatment working mode, the heating module (200) is heated to 103°C ± 2°C and outputs the steam required for work.

Images