Multi-section umbrella-shaped electrode

Abstract

The utility model provides a multi-section umbrella-shaped electrode, which comprises an electrode base and at least one electrode arm assembly, the electrode base is of a tubular structure, the electrode base is vertically arranged, the bottom of the electrode arm assembly is fixed in the electrode base in an insulating manner, each electrode arm assembly comprises at least four electrode arms, and the electrode arms are fixed on the electrode base. Each electrode arm comprises at least two segmented electrode arms and an insulating joint used for connecting the two segmented electrode arms, the segmented electrode arms and the insulating joints are both of tubular structures, and the two opposite segmented electrode arms are fixed to the same insulating joint in an inserted mode. And an inner hole of each segmented electrode arm is electrically connected with a power transmission line with an insulating skin. After the electrode arm is designed in sections, different sections of the electrode arm are operated by adopting the same or different frequencies and voltages, so that spherical or non-spherical liver tumor cell tissues can be ablated.

Description

Technical Field

[0001] This utility model relates to the field of radiofrequency ablation technology for liver tumors, and in particular to a multi-segment umbrella-shaped electrode. Background Technology

[0002] Radiofrequency ablation (RFA) is a physical therapy that uses radiofrequency current to excite ions in tissues to oscillate at high speeds, causing them to collide and rub against each other, generating high heat that dehydrates tumor cells and tissues, leading to localized coagulation necrosis. Due to its advantages such as being minimally invasive, economical, and safe, RFA technology is playing an increasingly important role in treating various tumors, including those of the liver, lungs, kidneys, prostate, pancreas, and uterine fibroids, as well as arrhythmias such as atrial fibrillation. The radiofrequency electrode needles are a key factor affecting the effectiveness of RFA. However, existing RFA electrode needles, because multiple needles are charged at each site, result in a relatively fixed area of ​​influence during use, which can easily damage nearby tissues.

[0003] For example, Chinese utility model patent CN219720847U discloses an improved umbrella-shaped electropulse ablation electrode needle, including a core electrode outer tube and multiple core electrodes that are movably inserted therein. The core electrodes can extend out of the core electrode outer tube and unfold into an umbrella shape. The front ends of both the core electrodes and the core electrode outer tube are provided with a discharge working part. The core electrode outer tube is movably inserted into an outer sheath tube, and the rear end of the outer sheath tube is connected to a handle. The rear end of the handle is connected to an external power supply through a tail wire. Operating the handle can drive the core electrodes to extend or retract into the core electrode outer tube. The discharge working part of the core electrode outer tube is a puncture head electrode fixed to the front end of the core electrode outer tube. A wire is inserted in the core electrode outer tube to connect the puncture head electrode for power supply. During operation, the puncture head electrode and the surrounding core electrodes are paired with a high-voltage pulse electric field to perform pulse ablation treatment on the tumor tissue in the surrounding area. Because the area damaged during the puncture process is fixed, it is impossible to avoid blood vessels for tissues and organs of limited volume, which can easily cause bleeding. Alternatively, being close to blood vessels can cause heat to be carried away by the blood flow, affecting the accumulation of heat, causing the heat-affected zone to shrink, resulting in insufficient tumor ablation and surgical failure. Utility Model Content

[0004] The technical problem to be solved by this utility model is to provide a multi-segment umbrella-shaped electrode, which, after segmenting the electrode arm, operates at different frequencies and voltages in different segments of the electrode arm, thereby ablating spherical and non-spherical liver tumor cells.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0006] A multi-segment umbrella-shaped electrode includes an electrode base and at least one electrode arm assembly. The electrode base is a tubular structure and is placed vertically. The bottom of the electrode arm assembly is insulated and fixed inside the electrode base. Each electrode arm assembly includes at least four electrode arms. Each electrode arm includes at least two segmented electrode arms and an insulating joint for connecting two segmented electrode arms. Both the segmented electrode arms and the insulating joint are tubular structures. Two opposite segmented electrode arms are inserted and fixed on the same insulating joint. An insulated power transmission wire is electrically connected to the inner hole of each segmented electrode arm.

[0007] Furthermore, in each of the electrode arm assemblies, at least four of the electrode arms are evenly distributed circumferentially.

[0008] Furthermore, the curved shape and size of the insulating joint are adapted to the curved shape and size of the two segmented electrode arms connected thereto. The wall thickness of the insulating joint is greater than the wall thickness of the two segmented electrode arms connected thereto. Stepped surfaces are machined around the two ends of the outer tube arm of the insulating joint, and the two segmented electrode arms connected thereto are respectively inserted and fixed on the stepped surfaces at both ends of the insulating joint.

[0009] Furthermore, each of the electrode arms comprises two, three, or four segmented electrode arms.

[0010] Furthermore, the electrode arm is arc-shaped, and the electrode arm is located in a vertical plane passing through the center line of the electrode base, or the electrode arm is inclined to the vertical plane passing through the center line of the electrode base.

[0011] Furthermore, the electrode arm comprises at least two sequentially connected arc segments, each with a different center point. The electrode arm is located in a vertical plane passing through the center line of the electrode base, or the different arc segments of the electrode arm are located on different spatial planes.

[0012] Furthermore, the electrode arm assembly has two sets, one set of electrode arms extending upwards and the other set of electrode arm assemblies extending downwards. The electrode arms in both sets of electrode arm assemblies are arc-shaped, wherein the radius of the upward-extending electrode arm is greater than the radius of the downward-extending electrode arm.

[0013] Furthermore, it also includes an electrode fixing plate, the bottom end of each electrode arm is fixed on the electrode fixing plate, and the electrode fixing plate is slidably disposed within the electrode base.

[0014] Furthermore, the electrode fixing plate is disc-shaped and has multiple rings of electrode mounting holes. The multiple electrode mounting holes are arranged at equal angles and the electrode mounting holes on the multiple rings are staggered. Each group of electrode arm assemblies occupies one ring of electrode mounting holes.

[0015] Furthermore, it also includes a pressure sensor and a temperature sensor, which are mounted on the head of the electrode arm assembly.

[0016] The beneficial effects of this invention are as follows: by designing the electrode arm in segments, the same or different frequencies and voltages are used to operate on different segments of the electrode arm, thereby ablation of spherical or non-spherical liver tumor cells. Attached Figure Description

[0017] Figure 1 This is a perspective view of one embodiment of the multi-segment umbrella-shaped electrode of this utility model;

[0018] Figure 2 This is an embodiment of the present utility model. Figure 1 Top view corresponding to the Chinese embodiment;

[0019] Figure 3 This is a schematic diagram of the electrode head and electrode tail structure in one embodiment of the multi-segment umbrella-shaped electrode of this utility model;

[0020] Figure 4 This is a comparison diagram of simulated ablation areas when different voltages are applied to the electrode head of the same umbrella electrode in one embodiment of the multi-segment umbrella electrode of this utility model.

[0021] Figure 5 This is a comparison diagram of simulated ablation regions when different voltages are applied to the electrode tail and electrode base of the same umbrella electrode in one embodiment of the multi-segment umbrella electrode of this utility model.

[0022] Figure 6 This is a schematic diagram of a simulated ablation region where different voltages are applied to different electrode heads of the same umbrella electrode in one embodiment of the multi-segment umbrella electrode of this utility model.

[0023] Figure 7 This is a partial cross-sectional view of the segmented electrode arm and the insulating joint being inserted and fixed according to an embodiment of the present invention;

[0024] Figure 8 This is a perspective view of one embodiment of the multi-segment umbrella-shaped electrode of this utility model;

[0025] Figure 9 This is an embodiment of the present utility model. Figure 8 Top view corresponding to the Chinese embodiment;

[0026] Figure 10 This is a perspective view of one embodiment of the multi-segment umbrella-shaped electrode of this utility model;

[0027] Figure 11 This is an embodiment of the present utility model. Figure 10 Top view corresponding to the Chinese embodiment;

[0028] Figure 12 This is a front view of one embodiment of the multi-segment umbrella-shaped electrode of this utility model;

[0029] Figure 13 This is an embodiment of the present utility model. Figure 12 A schematic diagram of the simulated ablation region corresponding to the multi-segment umbrella-shaped electrode;

[0030] Figure 14 This is a top view of the electrode fixing plate according to an embodiment of the present invention.

[0031] Label Explanation:

[0032] 1. Electrode base; 2. Electrode arm; 3. Electrode fixing plate; 4. Sleeve base;

[0033] 21. Segmented electrode arm; 22. Insulating joint; 23. Transmission line; 24. Arc segment;

[0034] 31. Electrode mounting hole. Detailed Implementation

[0035] To explain in detail the technical content, objectives, and effects of this utility model, the following description is provided in conjunction with the embodiments and accompanying drawings.

[0036] Please refer to Figures 1 to 14 The embodiments provided by this utility model are as follows:

[0037] A multi-segment umbrella-shaped electrode includes an electrode base 1 and at least one electrode arm 2 assembly. The electrode base 1 is a tubular structure and is placed vertically. The bottom of the electrode arm 2 assembly is insulated and fixed within the electrode base 1. Each electrode arm 2 assembly includes at least four electrode arms 2, and each electrode arm 2 includes at least two segmented electrode arms 21 and an insulating joint 22 for connecting two segmented electrode arms 21. Both the segmented electrode arms 21 and the insulating joint 22 are tubular structures. Two opposing segmented electrode arms 21 are inserted and fixed onto the same insulating joint 22. An insulated power transmission wire 23 is electrically connected to the inner hole of each segmented electrode arm 21. By segmenting each electrode arm 2, the same or different frequencies and voltages are used in different segments of the electrode arm 2, thereby ablating spherical or non-spherical liver tumor cells.

[0038] Furthermore, in each of the electrode arm 2 assemblies, at least four of the electrode arms 2 are evenly distributed around the circumference to make the range of tumor cell tissue that can be ablated as uniform as possible.

[0039] For further details, please see Figure 7 As shown, the curved shape and dimensions of the insulating joint 22 are adapted to the curved shape and dimensions of the two segmented electrode arms 21 connected thereto. The wall thickness of the insulating joint 22 is greater than the wall thickness of the two segmented electrode arms 21 connected thereto. Stepped surfaces are machined around both ends of the outer tube of the insulating joint 22, and the two segmented electrode arms 21 connected thereto are respectively inserted and fixed to the stepped surfaces at both ends of the insulating joint 22. After the insulating joint 22 is connected and fixed to the segmented electrode arms 21 connected thereto, the surface of the electrode arm 2 is smooth, which makes it less likely to damage human tissue, and minimizes the impact of the insulating joint 22 on the ablation range of the electrode arm 2.

[0040] Furthermore, it also includes an electrode fixing plate 3, on which the bottom end of each electrode arm 2 is fixed. The electrode fixing plate 3 is slidably disposed within the electrode base 1. The electrode fixing plate 3 is made of a high-temperature resistant and insulating ceramic material, such as PA66. The electrode base 1 itself is conductive, and its outer surface has an insulating coating or insulating tube, such as a Teflon coating or a tetrafluoroethylene tube, making its outer surface electrically insulating and self-lubricating, with the aim of reducing resistance during tissue insertion.

[0041] Furthermore, the electrode arm 2 is made of a nickel-titanium alloy with shape memory function and copper plating. Before surgery, the electrode arm 2 is retracted into the electrode base 1. During surgery, after the electrode base 1 is inserted into the human tissue, the electrode fixing plate 3 slides forward relative to the electrode base 1 until the electrode arm 2 unfolds into an umbrella shape. When the electrode is working, a certain voltage is applied to the electrode arm 2 and the electrode base 1 to ablate human tumor cells. After the tumor cells are eliminated, the electrode fixing plate 3 is pulled towards the hand to retract the electrode arm 2 into the electrode base 1, and the needle withdrawal begins. Voltage continues to be applied during the needle withdrawal process to suppress needle tract bleeding until the electrode base 1 is withdrawn outside the human body and no more voltage is applied, thus completing the surgery.

[0042] For further information, please refer to Figure 14 As shown, the electrode fixing plate 3 is disc-shaped and has multiple rings of electrode mounting holes 31. These holes are arranged at equal angles and staggered, with each electrode arm 2 assembly occupying one ring of electrode mounting holes 31. This design ensures that all electrode arms 2 are evenly distributed around their circumference and minimizes the diameter of the electrode arm 2 fixing plate and electrode base 1, thus reducing patient discomfort during surgery.

[0043] Furthermore, it also includes a pressure sensor, which is installed at the head of the electrode arm 2 assembly to detect the pressure in the tumor cell ablation area.

[0044] Furthermore, it also includes a temperature sensor, which is installed at the head of the electrode arm 2 assembly to detect the temperature of the tumor cell ablation area.

[0045] Furthermore, it also includes a cannula base 4, which is a tubular structure, and the electrode base 1 is fixed to the top of the cannula base 4. The cannula base 4 is used to facilitate gripping during surgery.

[0046] Furthermore, each of the electrode arms 2 includes two, three, or four segmented electrode arms 21.

[0047] The specific shape of electrode arm 2 is described below:

[0048] For further information, please refer to Figure 1 and Figure 2 As shown, the electrode arm 2 is arc-shaped, and each electrode arm 2 includes two segmented electrode arms 21. We call the segmented electrode arm 21 located near the electrode base 1 the electrode tail. For details of the electrode tail, please refer to [link to documentation]. Figure 3 The gray segmented electrode arm 21 in the right figure is called the electrode head, specifically the segment of the electrode arm 21 furthest from the electrode base 1. See [link to electrode head section] for details. Figure 3 In the left image, the gray segmented electrode arm 21 is located in a vertical plane passing through the center line of the electrode base 1. We will now apply a voltage to this electrode arm 2 to observe the simulated ablation region of the electrode, as detailed below:

[0049] For the first voltage application, we applied an equal voltage V0 to the electrode head, electrode tail, and electrode base 1, assuming V0 = 20V. The simulation results of thermal damage after energization are shown below. Figure 4 As shown in the left figure; for the second voltage application, we applied a voltage V = V0 + 5V to the electrode head and a voltage V0 to the electrode tail and electrode base 1. The simulation results of thermal damage after energization are shown in the figure. Figure 4 As shown in the right figure. (By...) Figure 4 It can be seen that as the applied voltage to the electrode head increases, the maximum outer diameter H of the mushroom head increases. Figure 4 The outer diameter H2 of the mushroom head in the right figure is greater than... Figure 4 The mushroom cap in the left figure has an outer diameter H1, and there is a tendency for the mushroom cap and root to expand outwards at their junction, but the maximum outer diameter W of the mushroom root does not change significantly. Figure 4 The outer diameter W2 of the mushroom root in the right figure is approximately Figure 4 The outer diameter W1 of the mushroom root in the left figure shows that increasing the voltage applied to the electrode head directly affects the heat-affected zone at the mushroom head location.

[0050] For the third voltage application, we applied voltage V0 to the electrode head and voltage V = V0 + 5V to the electrode tail and electrode base 1. The simulation results of thermal damage after energization are shown in [the figure]. Figure 5 As shown in the left figure; for the fourth voltage application, we applied voltage V0 to the electrode head and voltage V = V0 + 10V to the electrode tail and electrode base 1. The simulation results of thermal damage after energization are shown in the figure. Figure 5 As shown in the right figure. (By...) Figure 5 It can be seen that the voltage applied to the electrode tail and electrode base 1 is increased by 5V, which causes the axial central region and the top of the mushroom head and the area near the root of the mushroom head to expand outward; indicating that the increase in the voltage applied to the electrode tail and electrode base 1 will directly affect the heat-affected zone of the electrode tail and electrode base 1.

[0051] In summary, by Figure 4 and Figure 5 The conclusion is that the voltage at the electrode head affects the size of the mushroom head, while the size of the electrode tail and electrode base 1 affects the size of the mushroom shaft segment.

[0052] In reality, the tumor area to be ablated may have local distortions or be close to sensitive locations that need to be avoided. Similarly, by adjusting the applied voltage in segments (including applying different voltages within the same set of electrode arms 2, or applying different voltages to the same electrode arm 2, for example, applying different voltages to the four electrode heads respectively), the complex "conformity" requirements in clinical practice can be met, achieving precise control of the coagulation necrotic area, compressing the coagulation zone boundary, and reducing the sacrifice of healthy tissue.

[0053] For the fifth voltage application, we applied voltage V = V0 + 5V to electrode head 1, electrode head 2, and electrode head 3; voltage V = V0 - 5V to electrode head 4; and voltage V0 to electrode tail and electrode base 1. The simulation results of thermal damage after energization are shown in [the table / document / etc.]. Figure 6 As shown in the left figure, simulation results show that the thermal damage area formed around electrode 4 with a lower applied voltage shrinks significantly, and is much smaller than the thermal damage areas formed around electrode 1, electrode 2, and electrode 3 with higher applied voltages. This embodiment can be used in scenarios where tumors requiring protection exist around electrode 4, such as sensitive organs, blood vessels, bile ducts, or nerves.

[0054] For further information, please refer to Figure 8 and Figure 9 As shown, the electrode arm 2 is arc-shaped, and each electrode arm 2 includes two segmented electrode arms 21. The electrode arms 2 are inclined to a vertical plane passing through the center line of the electrode base 1.

[0055] For further information, please refer to Figure 10 and Figure 11As shown, the electrode arm 2 includes at least two sequentially connected arc segments 24, and the center points of each arc segment 24 are different. The different arc segments 24 of the electrode arm 2 are located on different spatial planes.

[0056] Furthermore, the electrode arm 2 comprises at least two sequentially connected arc segments 24, and the center points of each arc segment 24 are different. The electrode arm 2 is located in a vertical plane passing through the center line of the electrode base 1.

[0057] Furthermore, the electrode arm 2 assembly has two sets: one set of electrode arms 2 extending upwards, and the other set of electrode arms 2 extending downwards. Both sets of electrode arms 2 are arc-shaped, with the radius of the upward-extending electrode arm 2 being larger than the radius of the downward-extending electrode arm 2. Please refer to... Figure 12 and Figure 13 As shown, specifically, one set of electrode arms 2 is semi-circular and includes two segmented electrode arms 21, and the other set of electrode arms 2 is also semi-circular and includes two segmented electrode arms 21. The radius of one set of electrode arms 2 is 1.5 to 2.5 times the radius of the other set of electrode arms 2. The shape of the liver tumor cells that can be ablated by applying the same voltage and frequency to each set of electrode arms 2 is as follows. Figure 13 As shown, it is similar to a hemispherical shape. Of course, each of the upper and lower electrode arms 2 can be applied with different voltages and frequencies.

[0058] In summary, the multi-segment umbrella-shaped electrode provided by this utility model has a segmented design for the electrode arm 2, and the electrode arm 2 is a single arc shape, or it is designed to include multiple arc segments 24, so that the shape of the electrode arm 2 is no longer limited to a single arc shape. In addition, the same or different frequencies and voltages are used to operate on different segments of the electrode arm 2, thereby ablating spherical or non-spherical tumor cell tissues.

[0059] The above description is merely an embodiment of this utility model and does not limit the patent scope of this utility model. Any equivalent modifications made based on the content of this utility model specification and drawings, or direct or indirect applications in related technical fields, are similarly included within the patent protection scope of this utility model.

Claims

1. A multi-segment umbrella-shaped electrode, characterized in that, The assembly includes an electrode base (1) and at least one electrode arm (2) assembly. The electrode base (1) is a tubular structure and is placed vertically. The bottom of the electrode arm (2) assembly is insulated and fixed inside the electrode base (1). Each electrode arm (2) assembly includes at least four electrode arms (2). Each electrode arm (2) includes at least two segmented electrode arms (21) and an insulating joint (22) for connecting two segmented electrode arms (21). Both the segmented electrode arms (21) and the insulating joint (22) are tubular structures. Two opposite segmented electrode arms (21) are inserted and fixed on the same insulating joint (22). An insulated power transmission line (23) is electrically connected to the inner hole of each segmented electrode arm (21).

2. The multi-segment umbrella-shaped electrode according to claim 1, characterized in that, In each of the electrode arm (2) assemblies, at least four of the electrode arms (2) are evenly distributed around the circumference.

3. The multi-segment umbrella-shaped electrode according to claim 1, characterized in that, The curved shape and size of the insulating joint (22) are adapted to the curved shape and size of the two segmented electrode arms (21) connected thereto. The wall thickness of the insulating joint (22) is greater than the wall thickness of the two segmented electrode arms (21) connected thereto. Stepped surfaces are machined around the two ends of the outer tube arm of the insulating joint (22). The two segmented electrode arms (21) connected thereto are respectively inserted and fixed on the stepped surfaces at both ends of the insulating joint (22).

4. The multi-segment umbrella-shaped electrode according to claim 1, characterized in that, Each of the electrode arms (2) includes two, three, or four segmented electrode arms (21).

5. The multi-segment umbrella-shaped electrode according to claim 1, characterized in that, The electrode arm (2) is arc-shaped and is located in a vertical plane passing through the center line of the electrode base (1), or the electrode arm (2) is inclined to the vertical plane passing through the center line of the electrode base (1).

6. The multi-segment umbrella-shaped electrode according to claim 1, characterized in that, The electrode arm (2) comprises at least two sequentially connected arc segments (24), and the center points of each arc segment (24) are different. The electrode arm (2) is located in a vertical plane passing through the center line of the electrode base (1), or the different arc segments (24) of the electrode arm (2) are located on different spatial planes.

7. The multi-segment umbrella-shaped electrode according to claim 1, characterized in that, The electrode arm (2) assembly has two sets. One set of electrode arms (2) extends upward, and the other set of electrode arms (2) extends downward. Both sets of electrode arms (2) are arc-shaped, and the radius of the upward-extending electrode arm (2) is greater than the radius of the downward-extending electrode arm (2).

8. The multi-segment umbrella-shaped electrode according to claim 1, characterized in that, It also includes an electrode fixing plate (3), the bottom end of each electrode arm (2) is fixed on the electrode fixing plate (3), and the electrode fixing plate (3) is slidably disposed in the electrode base (1).

9. The multi-segment umbrella-shaped electrode according to claim 8, characterized in that, The electrode fixing plate (3) is disc-shaped and has multiple rings of electrode mounting holes (31). The multiple electrode mounting holes (31) are arranged at equal angles and the electrode mounting holes (31) on the multiple rings are staggered. Each group of electrode arm (2) assemblies occupies one ring of electrode mounting holes (31).

10. The multi-segment umbrella-shaped electrode according to claim 1, characterized in that, It also includes a pressure sensor and a temperature sensor, which are mounted on the head of the electrode arm (2) assembly.

Images