A bipolar needle system suitable for steep pulse ablation

Abstract

The present invention discloses a bipolar needle system suitable for steep pulse ablation, comprising a bipolar needle, a steep pulse generating module and a current monitoring module. The bipolar needle comprises a front electrode, a rear electrode, a wire, an insulating ring, an insulating support ring and a conductive connecting tube, and the front end of the bipolar needle front electrode forms the needle tip of the bipolar needle. The front end of the bipolar needle insulating support ring is connected to the rear end of the bipolar needle front electrode; the bipolar needle insulating ring and the bipolar needle rear end electrode are both sleeved and installed outside the bipolar needle insulating support ring, the front end of the bipolar needle insulating ring is connected to the rear end of the bipolar needle front electrode, the rear end of the bipolar needle insulating ring is connected to the front end of the bipolar needle rear end electrode, and the rear end of the bipolar needle rear end electrode extends out of the bipolar needle insulating support ring. The front end of the bipolar needle wire extends from the rear end of the bipolar needle insulating support ring into the bipolar needle insulating support ring and is connected to the rear end of the bipolar needle front electrode.

Description

Technical Field

[0001] The invention belongs to the technical field of medical devices, and in particular relates to a bipolar needle system suitable for steep pulse ablation. Background Art

[0002] In the field of tumor treatment, irreversible electroporation technology has attracted widespread attention from researchers in the field of bioelectrics at home and abroad for its advantages such as rapidity, controllability, visibility, selectivity and non-thermal mechanism, and has gradually been applied to the clinical treatment of tumors. The treatment mechanism of irreversible electroporation technology is to generate high-voltage ultra-short nanosecond pulses through a high-voltage power supply and a pulse generator, emit ultra-short pulses of a certain frequency, release electrical energy through electrodes in the form of pulsed electric fields, and transmit the electric field energy to tumor tissues through electrode needles to cause irreversible electroporation and apoptosis of tumor cells. Among them, the electrode needle is a key component of irreversible electroporation technology for treating tumors, and it plays a vital role in the effect of irreversible electroporation.

[0003] The principle of irreversible electroporation therapy, also known as steep pulse therapy, is that the steep pulse output and control device transmits pulsed high-voltage electrical energy to the lesion site in need of treatment through the steep pulse electrode needle. During the energy output process, the lesion site is affected by the pulsed high-voltage electricity, the cell membrane of the tissue cells is broken down by the electrical energy, and electrolytes such as cell fluid flow out of the cells. This process will cause the impedance of the treatment circuit composed of the human body, steep pulse electrode needle, steep pulse output and control equipment to become lower and lower, and the current in the treatment circuit will become larger and larger. Conversely, when the current in the treatment circuit becomes larger and larger, it means that the impedance in the treatment circuit is getting lower and lower, which means that more and more lesion cells are broken down. Based on the above principle, the steep pulse output and control device samples the current change value in the treatment circuit to obtain the current size and thus judge the situation of the lesion cells that have been broken down.

[0004] For the lesion cells, the larger the current, the more thoroughly the lesion cells are eliminated. However, the current that the human body can withstand is not the larger the better. There is a safety limit. When this safety limit is reached, the steep pulse output and control equipment must stop the energy output. Therefore, in the treatment circuit composed of the human body, steep pulse electrodes, steep pulse output and control equipment, the accuracy of current collection is particularly important.

[0005] The electrode needle suitable for irreversible electroporation therapy (that is, steep pulse ablation therapy) in the prior art generally includes an electrode head, a positive electrode, a negative electrode and a metal conductive tube, etc., and the front end of the metal conductive tube is connected to the electrode head, and the negative electrode and the positive electrode are both arranged outside the metal conductive tube, the front end of the negative electrode is connected to the electrode head, and an insulating part is provided between the rear end of the negative electrode and the front end of the positive electrode, and an insulating part is also provided between the positive electrode and the metal conductive tube. Ideally, the current flows into the metal conductive tube, passes through the electrode head, the negative electrode, the lesion site, the positive electrode in turn, and then flows out, such as the water circulation steep pulse electrode needle disclosed in patent CN202222019196.1.

[0006] However, in actual use, this type of electrode needle may experience a situation where the current suddenly increases to exceed the safety limit at the moment of power-on (that is, the moment when the steep pulse output and control device just starts to output current). The steep pulse output and control device will mistakenly believe that the safety limit has been reached and stop energy output, which may cause surgery to be delayed or fail to achieve full treatment effects. Summary of the invention

[0007] In view of the above problems, the present invention provides a bipolar needle system suitable for steep pulse ablation.

[0008] The technical solution of the present invention is:

[0009] A bipolar needle system suitable for steep pulse ablation, comprising a bipolar needle, a steep pulse generating module and a current monitoring module;

[0010] The bipolar needle comprises a front electrode, a rear electrode, a wire, an insulating ring and an insulating support ring, and the front end of the front electrode forms the needle tip of the bipolar needle;

[0011] The front end of the insulating support ring is connected to the rear end of the front electrode; the insulating ring and the rear end electrode are both sleeved and installed outside the insulating support ring, the front end of the insulating ring is connected to the rear end of the front electrode, the rear end of the insulating ring is connected to the front end of the rear end electrode, and the rear end of the rear end electrode extends out of the insulating support ring;

[0012] The front end of the wire extends from the rear end of the insulating support ring into the insulating support ring and is connected to the rear end of the front electrode;

[0013] The steep pulse generating module is used to output a high-voltage steep pulse current; the output end of the steep pulse generating module for outputting the high-voltage steep pulse current is connected to the rear end of the wire, and the high-voltage steep pulse current reaches the front electrode through the wire; the input end of the steep pulse generating module for receiving the return current is connected to the rear electrode, and the return current reaches the steep pulse generating module through the rear electrode;

[0014] The current monitoring module is connected to the steep pulse generating module, and the current monitoring module is used to monitor the current output by the steep pulse generating module in real time; the steep pulse generating module is also used to automatically cut off the output of the current when the current monitoring module detects that the current exceeds a threshold.

[0015] In a preferred embodiment of the bipolar needle system suitable for steep pulse ablation, the insulating support ring is made of ceramic material or high-strength polymer plastic.

[0016] A bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment also includes a conductive connecting tube; the conductive connecting tube is located inside the insulating support ring, and the front end of the conductive connecting tube is connected to the rear end of the front end electrode; the conductive connecting tube is sleeved outside the wire, and the conductive connecting tube is connected to the front end of the wire.

[0017] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the wire is connected to the conductive connection tube by welding;

[0018] The conductive connection tube contains tin liquid for welding, and the front end of the wire is fixedly connected to the solidified tin liquid in the conductive connection tube.

[0019] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the guide wire comprises a guide wire inner core and a guide wire insulation layer wrapped around the guide wire inner core, and the front end of the guide wire inner core extends out of the guide wire insulation layer;

[0020] The front end of the wire core and the front end of the wire insulation layer are both fixedly connected to the solidified tin liquid in the conductive connecting tube; or, only the front end of the wire core is fixedly connected to the solidified tin liquid in the conductive connecting tube, and the wire insulation layer does not contact the tin liquid.

[0021] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the rear end electrode, the insulating support ring and the conductive connecting tube have an overlapping portion in the radial direction of the bipolar needle, and at the overlapping portion, the thickness of the insulating support ring is greater than 1.5 times the thickness of the rear end electrode, and the thickness of the insulating support ring is greater than 1.5 times the thickness of the conductive connecting tube.

[0022] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, at the overlapping part of the rear end electrode, the insulating support ring and the conductive connecting tube, the thickness of the insulating support ring is 0.18 mm to 0.22 mm, the thickness of the rear end electrode is 0.06 mm to 0.10 mm, and the thickness of the conductive connecting tube is 0.06 mm to 0.10 mm.

[0023] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the front end of the conductive connection tube is welded to the rear end of the front electrode.

[0024] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the rear end of the front electrode has a first step portion, and the first step portion includes a first outer side wall in the circumferential direction of the front electrode and a first end surface of the front electrode facing the rear end direction;

[0025] The front end of the conductive connection tube is sleeved outside the first outer side wall, and the front end of the conductive connection tube is connected to the first step portion.

[0026] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the rear end of the front electrode has a first step portion, and the first step portion includes a first outer side wall in the circumferential direction of the front electrode and a first end surface of the front electrode facing the rear end direction;

[0027] The front end of the conductive connection tube is sleeved outside the first outer side wall, and the front end of the conductive connection tube is welded to the first step portion;

[0028] After the conductive connecting tube is sleeved on the first outer wall, the rear end face of the front electrode in the conductive connecting tube is the central end face, and the central end face and the inner wall of the conductive connecting tube form a tin liquid containing groove, and the unsolidified tin liquid is contained in the tin liquid containing groove, and the front end of the wire extends from the rear end of the conductive connecting tube into the conductive connecting tube and into the unsolidified tin liquid in the tin liquid containing groove.

[0029] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the front end of the conductive connection tube is connected to the first step portion by laser welding.

[0030] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the rear end of the front electrode also has a second step portion, and the second step portion is located on the outer layer of the first step portion; the front end of the insulating support ring is arranged outside the second step portion, and the front end of the insulating support ring and the front end of the insulating ring are respectively connected to the second step portion to achieve connection with the rear end of the front electrode.

[0031] In a bipolar needle system suitable for steep pulse ablation provided by a preferred embodiment, the front end of the insulating support ring and the front end of the insulating ring are both welded to the second step portion.

[0032] In a preferred embodiment of the bipolar needle system suitable for steep pulse ablation, the inner core of the wire is made of copper alloy.

[0033] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art:

[0034] The bipolar needle system suitable for steep pulse ablation provided by the present invention has a high-voltage steep pulse current output by the steep pulse generating module, which flows to the input end of the steep pulse generating module after passing through the wire, the front electrode, the lesion site, and the back electrode in sequence. During use, the current flows accurately, and the current will not increase to exceed the safety limit at the moment of power-on.

[0035] The bipolar needle system suitable for steep pulse ablation provided by the present invention realizes insulation isolation of the rear-end electrode and the guide wire (here mainly referring to the inner core of the guide wire exposed to the outside) by the provision of an insulating support. At the same time, the provision of the insulating support can improve the strength of the needle head area of ​​the bipolar needle (the needle head area includes the needle tip and some structures near the needle tip). BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the following detailed description of the preferred embodiment.The drawings are only for the purpose of illustrating the preferred embodiments and are not to be construed as limiting the invention.

[0037] Figure 1 It is a structural schematic diagram of the front end portion of a bipolar needle of the present invention;

[0038] Figure 2 A schematic cross-sectional view of the front end portion of a bipolar needle of the present invention (the tin liquid is not shown in the figure);

[0039] Figure 3 A schematic cross-sectional view of a partial structure of a bipolar needle of the present invention (the tin liquid is not shown in the figure);

[0040] Figure 4 It is a schematic structural diagram of a front-end electrode of the present invention;

[0041] Figure 5 A waveform diagram corresponding to a water circulation steep pulse electrode needle in the prior art;

[0042] Figure 6 This is a waveform diagram corresponding to a bipolar needle system suitable for steep pulse ablation of the present invention.

[0043] Description of reference numerals:

[0044] 1: front end electrode; 11: first step portion; 111: first outer side wall; 112: first end face; 12: second step portion; 121: second outer side wall; 122: second end face; 2: insulating ring; 3: insulating support ring; 4: conductive connecting tube; 5: rear end electrode; 6: wire insulation layer; 7: wire core; 8: needle tube insulation layer. DETAILED DESCRIPTION

[0045] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0046] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0047] Since the external manifestation caused by the instantaneous increase of current exceeding the safety limit when power is on in the prior art is the same as the external manifestation of the current exceeding the safety limit due to the breakdown of more and more diseased cells, both of which monitor the return current increasing to exceed the safety limit and cause the steep pulse output and the control device to automatically cut off the current output, the electrode needle in the prior art has not been found to have such a problem.

[0048] The reason why the current of the electrode needle in the prior art increases to exceed the safety limit at the moment of power-on is that the negative electrode and the metal conductive tube are both round tube styles, the negative electrode is sleeved on the metal conductive tube and the distance between the two is extremely small, so that a capacitor structure is formed between the negative electrode and the metal conductive tube; at the moment of power-on, the initial state of this capacitor structure is an uncharged state, which is equivalent to a short circuit, and the current will flow rapidly to charge the capacitor structure. During this charging process, the voltage of the capacitor structure increases rapidly from zero to the power supply voltage; since the voltage of the capacitor structure cannot change suddenly, at the moment of power-on, the capacitor structure will quickly build up the voltage by absorbing a large amount of current, which will cause the current in the circuit to increase instantaneously.

[0049] At the same time, during the steep pulse treatment process, the amount of electrical energy used to penetrate the cell membrane of tissue cells at the lesion site is crucial. However, the amount of electrical energy cannot be directly measured, so it is usually replaced by the amount of electrical energy output by the steep pulse output and control device. However, due to the existence of the capacitor structure, part of the electrical energy output by the steep pulse output and control device will be wasted on the capacitor structure, resulting in a difference between the electrical energy output by the steep pulse output and control device and the electrical energy actually reaching the lesion site. Therefore, even if the current at the moment of power-on does not increase to the safety limit due to the sudden increase of the capacitor structure, the steep pulse output and control device smoothly outputs electrical energy, but there is already a difference between the electrical energy output by the steep pulse output and control device and the electrical energy actually reaching the lesion site, but the operator (usually a doctor) still equates the electrical energy output by the steep pulse output and control device with the electrical energy actually reaching the lesion site, which will result in poor treatment effect.

[0050] To solve the above problems, this embodiment provides a new bipolar needle system suitable for steep pulse ablation. Figures 1 to 4 The bipolar needle system suitable for steep pulse ablation includes a bipolar needle, a steep pulse generating module and a current monitoring module. The bipolar needle includes a front electrode 1, a rear electrode 5, a wire, an insulating ring 2 and an insulating support ring 3. The front end of the front electrode 1 forms the needle tip of the bipolar needle. The front end of the insulating support ring 3 is connected to the rear end of the front electrode 1; the insulating ring 2 and the rear electrode 5 are both sleeved outside the insulating support ring 3, the front end of the insulating ring 2 is connected to the rear end of the front electrode 1, the rear end of the insulating ring 2 is connected to the front end of the rear electrode 5, and the rear end of the rear electrode 5 extends out of the insulating support ring 3. The front end of the wire extends from the rear end of the insulating support ring 3 into the insulating support ring 3 and is connected to the rear end of the front electrode 1.

[0051] The steep pulse generating module is used to output high-voltage steep pulse current. The output terminal of the steep pulse generating module for outputting high-voltage steep pulse current is connected to the rear end of the wire, and the high-voltage steep pulse current reaches the front electrode through the wire. The input terminal of the steep pulse generating module for receiving the return current is connected to the rear electrode, and the return current reaches the steep pulse generating module through the rear electrode.

[0052] The current monitoring module is connected to the steep pulse generation module, and the current monitoring module is used to monitor the current output by the steep pulse generation module in real time. The steep pulse generation module is also used to automatically cut off the output of the current when the current monitoring module detects that the current exceeds a threshold value (the threshold value is the above-mentioned safety limit). The current monitoring module is mainly used to prevent the current from exceeding the upper limit that the human body can accept.

[0053] In the bipolar needle system suitable for steep pulse ablation provided in this embodiment, the high-voltage steep pulse current output by the steep pulse generation module flows to the input end of the steep pulse generation module after passing through the wire, the front electrode, the lesion site, and the back electrode in sequence. In the bipolar needle system of this embodiment, there is no capacitor structure in the bipolar needle, so during use, the current flows accurately, and the current will not increase to exceed the safety limit at the moment of power-on.

[0054] At the same time, the setting of the insulating support can insulate and isolate the rear end electrode 5 and the wire (here mainly referring to the wire core 7 exposed outside the wire); and the setting of the insulating support can improve the strength of the needle head area of ​​the bipolar needle (the needle head area includes the needle tip and some structures near the needle tip).

[0055] The bipolar needle system suitable for steep pulse ablation of this embodiment is further described below.

[0056] In this embodiment, the front electrode 1 is directly used as the needle tip of the bipolar needle, so the front end of the front electrode 1 forms a tip, which can be a sharp triangle. The rear end of the front electrode 1 has a first step portion 11 and a second step portion 12, and the second step portion 12 is located on the outer layer of the first step portion 11.

[0057] The front end of the insulating support ring 3 is sleeved outside the second step portion 12. Specifically, the second step portion 12 includes a second outer side wall 121 in the circumferential direction of the front electrode 1 and a second end face 122 on the front electrode 1 facing the rear end direction. The front end of the insulating support ring 3 is sleeved on the second outer side wall 121. The front end of the insulating support ring 3 and the front end of the insulating ring 2 are respectively connected to the second step portion 12, thereby realizing the connection with the rear end of the front electrode 1. Preferably, the connection method can be welding connection.

[0058] The needle tip of a bipolar needle generally includes a needle tip and an area near the needle tip, and the needle tip of a bipolar needle generally requires a certain structural strength. Therefore, the insulating support ring 3 is preferably made of ceramic material or high-strength polymer plastic (such as polyetheretherketone) to increase the structural strength of the needle tip.

[0059] In this embodiment, the bipolar needle tube assembly includes a conductive connection tube 4, and the front end electrode 1 and the wire are not directly fixedly connected but are fixedly connected through the conductive connection tube 4. Specifically, the conductive connection tube 4 is located in the insulating support ring 3, the front end of the conductive connection tube 4 is connected to the rear end of the front end electrode 1, the conductive connection tube 4 is sleeved outside the wire, and the conductive connection tube 4 is connected to the front end of the wire.

[0060] Preferably, the front end of the conductive connection tube 4 is welded to the rear end of the front electrode 1. Specifically, in the front electrode 1, the first step portion 11 includes a first outer side wall 111 in the circumferential direction of the front electrode 1 and a first end surface 112 on the front electrode 1 facing the rear end; the front end of the conductive connection tube 4 is sleeved outside the first outer side wall 111, and the front end of the conductive connection tube 4 is connected to the first step portion 11. More preferably, the front end of the conductive connection tube 4 is laser welded to the first step portion 11.

[0061] The connection between the wire and the conductive connection tube 4 is preferably by welding. Specifically, the conductive connection tube 4 contains tin liquid for welding, and the front end of the wire extends into the tin liquid before the tin liquid solidifies. When the tin liquid solidifies in the conductive connection tube 4, the front end of the wire will be fixedly connected to the solidified tin liquid in the conductive connection tube 4. At the same time, the solidified tin liquid is respectively connected to the conductive connection tube 4 and the wire, so that the conductive connection tube 4 and the wire can be energized smoothly.

[0062] The wire includes a wire core 7 and a wire insulation layer 6 wrapped around the wire core 7. The front end of the wire core 7 extends out of the wire insulation layer 6, that is, the front end of the wire core 7 will be partially exposed to the outside (the outside here refers to the inside relative to the inside formed by the wire insulation layer 6), and the exposed wire core 7 is electrically connected to the conductive connecting tube 4.

[0063] The front end of the wire is fixedly connected to the solidified tin liquid in the conductive connection tube 4. It can be that: the front end of the wire core 7 and the front end of the wire insulation layer 6 are both fixedly connected to the solidified tin liquid in the conductive connection tube 4, or only the front end of the wire core 7 is fixedly connected to the solidified tin liquid in the conductive connection tube 4, and the wire insulation layer 6 does not contact the tin liquid. The difference between the two is that when the tin liquid is not solidified, the front end of the wire extends into the unsolidified tin liquid for a long time. When the length of the wire extending into the unsolidified tin liquid is long, the front end of the wire core 7 and the front end of the wire insulation layer 6 will be fixed in the solidified tin liquid after the tin liquid solidifies. When the length of the wire extending into the unsolidified tin liquid is at the end, only the front end of the wire core 7 is fixed in the solidified tin liquid.

[0064] Since the operator needs to tighten the wire when controlling the needle tip of the bipolar needle when operating the bipolar needle, in this embodiment, it is preferred that the front end of the wire core 7 and the front end of the wire insulation layer 6 are fixedly connected to the solidified tin liquid in the conductive connecting tube 4. In this way, the connection strength between the wire and the conductive connecting tube 4 can be increased, and the wire insulation layer 6 can also be used to help the wire core 7 share the tension on the wire (if only the wire core 7 is fixed in the solidified tin liquid, then only the wire core 7 bears the tension when the wire is pulled), thereby making the front end electrode 1 not easy to loosen and the front end electrode 1 and the wire not easy to disconnect and fall off. Among them, the front end electrode 1 is not easy to loosen means that the front end electrode 1 can perform specific actions only by tightening and straightening the wire. When only the wire core 7 is fixed in the solidified tin liquid, only the wire core 7 can withstand the tension on the wire. Compared with the situation where the wire core 7 and the wire insulation layer 6 are simultaneously fixed in the solidified tin liquid, the straightening tension that the wire can withstand is smaller, and the front end electrode 1 is not pulled tight enough by the wire, so it may become loose; the front end electrode 1 and the wire are not easy to disconnect and fall off means that the wire is fixed in the solidified tin liquid to achieve a fixed connection between the wire and the conductive connecting tube 4. Compared with only the wire core 7 fixed in the solidified tin liquid, when the guide core and the guide insulation layer are simultaneously fixed in the solidified tin liquid, the connection between the wire and the conductive connecting tube 4 is more secure, that is, the front end electrode 1 and the wire are less likely to disconnect and fall off.

[0065] At the same time, the wire core 7 is preferably made of copper alloy (or other materials with high strength and higher conductivity). On the one hand, it ensures that the connection strength between the needle tip (front electrode 1) and the needle body (rear electrode 5, wire, etc.) is higher and the structure is more reliable. On the other hand, the resistance of the wire core 7 is smaller, and the energy lost in the wire core 7 is smaller. In this embodiment, the wire core 7 should not be made of copper wire, silver wire and other materials. Although these materials have high conductivity and low resistance, the material strength is low. The bipolar needle tube assembly will be subjected to a radial bending force when working, and the wire needs to be tightened and straightened. If the wire material strength is low, there will be a risk of loosening of the front electrode 1 and disconnection and falling of the front electrode 1 and the wire.

[0066] The specific method of welding the front end of the wire to the conductive connection tube 4 through tin liquid can be: after the conductive connection tube 4 is sleeved on the first outer wall 111, the rear end face of the front end electrode 1 in the conductive connection tube 4 is the central end face, and the central end face and the inner wall of the conductive connection tube 4 form a tin liquid containing groove, and the unsolidified tin liquid is contained in the tin liquid containing groove, and the front end of the wire extends from the rear end of the conductive connection tube 4 into the conductive connection tube 4 and into the unsolidified tin liquid in the tin liquid containing groove. When the tin liquid solidifies, the front end of the wire is fixedly connected to the solidified tin liquid. Of course, in other facility examples, other methods can also be used to achieve welding of the front end of the wire and the conductive connection tube 4 using tin liquid, which is not limited here.

[0067] In the prior art, if the wire is to be connected to the front-end electrode 1, a connection method of punching holes on the front-end electrode 1 and crimping the wire is generally used. In this embodiment, the connection between the wire and the front-end electrode 1 is transitioned by a conductive connection tube 4, one end of the conductive connection tube 4 is welded to the front-end electrode 1, and the other end is welded to the wire using tin liquid; the connection method of transition connection by the conductive connection tube 4 makes it easier to achieve the connection between the front-end electrode 1 and the wire in a small space, and the structure is more optimized than directly punching holes on the front-end electrode 1 and crimping the wire, and the difficulty of process implementation is greatly reduced.

[0068] Furthermore, in this embodiment, the rear end electrode, the insulating support ring and the conductive connection tube have an overlapping portion in the radial direction of the bipolar needle. At the overlapping portion, the thickness of the insulating support ring is greater than 1.5 times the thickness of the rear end electrode, and the thickness of the insulating support ring is greater than 1.5 times the thickness of the conductive connection tube. Specifically, the thickness of the insulating support ring is 0.18 mm to 0.22 mm, the thickness of the rear end electrode is 0.06 mm to 0.10 mm, and the thickness of the conductive connection tube is 0.06 mm to 0.10 mm. More preferably, the thickness of the insulating support ring can be 0.20 mm, and the thickness of the rear end electrode and the conductive connection tube can both be 0.08 mm.

[0069] The bipolar needle tube assembly further includes a needle tube insulation layer 8 , which is sleeved outside the rear end electrode 5 , and the front end of the rear end electrode 5 extends out of the needle tube insulation layer 8 .

[0070] The current monitoring module is mainly used to monitor the current in the treatment circuit; the steep pulse generation module at least includes the function of outputting high-voltage steep pulse current and cutting off the output of the current when the current monitoring module detects that the current exceeds the safety limit. The steep pulse generation module and the current monitoring module are both commonly used modules in steep pulse therapy. As long as the functions of the two can be realized, there is no restriction on their specific structures. For example, the circuits disclosed in patents CN118244633A and CN116509534A can be used.

[0071] In the prior art, since the metal conductive tube is sleeved in the negative electrode and the positive electrode, it is easy to form capacitive coupling, which causes the current to increase to exceed the safety limit at the moment of power-on. At this time, the current monitoring module detects that the current exceeds the safety limit, but the steep pulse generating module cannot distinguish whether the current is too large due to capacitive coupling or because the lesion cells are broken down too much and the current reaches the safety limit. Therefore, the steep pulse generating device will cut off the output of the current. In fact, if the current is too large due to capacitive coupling, the excessive current will directly reach the capacitor structure, and will not pass through the lesion site, that is, it will not flow through the human body. Therefore, there is no need to stop the current output of the steep pulse generating module. As long as the capacitor structure is charged, the current will naturally return to normal. The steep pulse generating module will mistake the excessive current caused by capacitive coupling as the current passing through the human body has reached the safety limit, and stop the energy output, which will cause the operation to be delayed or the treatment effect is not fully achieved.

[0072] The bipolar needle system suitable for steep pulse ablation provided in this embodiment optimizes the structure of the bipolar needle, effectively eliminating the possibility of capacitive coupling, that is, the capacitive coupling in the prior art will not cause the current to increase to more than the safety limit at the moment of power-on. At the same time, there is no capacitor structure to consume additional energy, which improves the effectiveness and reliability of the bipolar needle system suitable for steep pulse ablation of this embodiment.

[0073] Figure 5 , Figure 6 The current waveform is the change of the pulse current in the loop measured by using a current clamp under the same test voltage and resistance conditions for the electrode needle in the prior art and the bipolar needle in this embodiment. Figure 5 ( Figure 5 Corresponding to the prior art), it can be seen that there is a large sudden peak in the current in the loop. The sudden peak is a sudden increase in current caused by the capacitor structure. The existence of the sudden peak indicates the existence of the capacitor structure. Figure 6 ( Figure 6 It can be clearly seen in the corresponding embodiment that the peak of the current waveform is effectively eliminated.

[0074] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A bipolar needle system suitable for steep pulse ablation, characterized in that: It includes a bipolar needle, a steep pulse generation module and a current monitoring module; The bipolar needle comprises a front electrode, a rear electrode, a wire, an insulating ring and an insulating support ring, and the front end of the front electrode forms the needle tip of the bipolar needle; The front end of the insulating support ring is connected to the rear end of the front electrode; the insulating ring and the rear end electrode are both sleeved and installed outside the insulating support ring, the front end of the insulating ring is connected to the rear end of the front electrode, the rear end of the insulating ring is connected to the front end of the rear end electrode, and the rear end of the rear end electrode extends out of the insulating support ring; The front end of the wire extends from the rear end of the insulating support ring into the insulating support ring and is connected to the rear end of the front electrode; The steep pulse generating module is used to output high-voltage steep pulse current; The output end of the steep pulse generating module for outputting high-voltage steep pulse current is connected to the rear end of the wire, and the high-voltage steep pulse current reaches the front electrode through the wire; the input end of the steep pulse generating module for receiving return current is connected to the rear end electrode, and the return current reaches the steep pulse generating module through the rear end electrode; The current monitoring module is connected to the steep pulse generating module, and the current monitoring module is used to monitor the current output by the steep pulse generating module in real time; the steep pulse generating module is also used to automatically cut off the output of the current when the current monitoring module detects that the current exceeds a threshold.

2. The bipolar needle system suitable for steep pulse ablation according to claim 1, characterized in that: The insulating support ring is made of ceramic material or high-strength polymer plastic.

3. The bipolar needle system suitable for steep pulse ablation according to claim 1, characterized in that: It also includes a conductive connecting tube; the conductive connecting tube is located in the insulating support ring, and the front end of the conductive connecting tube is connected to the rear end of the front end electrode; the conductive connecting tube is sleeved outside the wire, and the conductive connecting tube is connected to the front end of the wire.

4. The bipolar needle system suitable for steep pulse ablation according to claim 3, characterized in that: The wire is connected to the conductive connection tube by welding; The conductive connection tube contains tin liquid for welding, and the front end of the wire is fixedly connected to the solidified tin liquid in the conductive connection tube.

5. The bipolar needle system suitable for steep pulse ablation according to claim 4, characterized in that: The wire comprises a wire inner core and a wire insulation layer wrapped around the wire inner core, and the front end of the wire inner core extends out of the wire insulation layer; The front end of the wire core and the front end of the wire insulation layer are both fixedly connected to the solidified tin liquid in the conductive connecting tube; or, only the front end of the wire core is fixedly connected to the solidified tin liquid in the conductive connecting tube, and the wire insulation layer does not contact the tin liquid.

6. The bipolar needle system suitable for steep pulse ablation according to any one of claims 3 to 5, characterized in that: The rear end electrode, the insulating support ring and the conductive connecting tube have an overlapping portion in the radial direction of the bipolar needle. At the overlapping portion, the thickness of the insulating support ring is greater than 1.5 times the thickness of the rear end electrode, and the thickness of the insulating support ring is greater than 1.5 times the thickness of the conductive connecting tube.

7. The bipolar needle system suitable for steep pulse ablation according to claim 6, characterized in that: At the overlapping portion of the rear end electrode, the insulating support ring and the conductive connection tube, the thickness of the insulating support ring is 0.18 mm to 0.22 mm, the thickness of the rear end electrode is 0.06 mm to 0.10 mm, and the thickness of the conductive connection tube is 0.06 mm to 0.10 mm.

8. The bipolar needle system suitable for steep pulse ablation according to claim 3, characterized in that: The front end of the conductive connection tube is welded to the rear end of the front end electrode.

9. The bipolar needle system suitable for steep pulse ablation according to claim 3, characterized in that: The rear end of the front electrode has a first step portion, and the first step portion includes a first outer side wall in the circumferential direction of the front electrode and a first end surface of the front electrode facing the rear end direction; The front end of the conductive connection tube is sleeved outside the first outer side wall, and the front end of the conductive connection tube is connected to the first step portion.

10. The bipolar needle system suitable for steep pulse ablation according to claim 4, characterized in that: The rear end of the front electrode has a first step portion, and the first step portion includes a first outer side wall in the circumferential direction of the front electrode and a first end surface of the front electrode facing the rear end direction; The front end of the conductive connection tube is sleeved outside the first outer side wall, and the front end of the conductive connection tube is welded to the first step portion; After the conductive connecting tube is sleeved on the first outer wall, the rear end face of the front electrode in the conductive connecting tube is the central end face, and the central end face and the inner wall of the conductive connecting tube form a tin liquid containing groove, and the unsolidified tin liquid is contained in the tin liquid containing groove, and the front end of the wire extends from the rear end of the conductive connecting tube into the conductive connecting tube and into the unsolidified tin liquid in the tin liquid containing groove.

11. The bipolar needle system suitable for steep pulse ablation according to claim 9 or 10, characterized in that: The front end of the conductive connection tube is connected to the first step portion by laser welding.

12. The bipolar needle system suitable for steep pulse ablation according to claim 9 or 10, characterized in that: The rear end of the front end electrode also has a second step portion, which is located on the outer layer of the first step portion; the front end of the insulating support ring is sleeved outside the second step portion, and the front end of the insulating support ring and the front end of the insulating ring are respectively connected to the second step portion to achieve connection with the rear end of the front end electrode.

13. The bipolar needle system suitable for steep pulse ablation according to claim 12, characterized in that: The front end of the insulating support ring and the front end of the insulating ring are both connected to the second step portion by welding.

14. The bipolar needle system suitable for steep pulse ablation according to claim 5, characterized in that: The inner core of the conductor is made of copper alloy.

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