A microwave ablation antenna based on flexible substrate integrated coaxial line

Abstract

This invention discloses a microwave ablation antenna based on a flexible substrate integrated coaxial line, comprising a microwave feeding structure, an impedance matching network, a microwave radiating structure, and a covering film structure. The microwave feeding structure, impedance matching network, and microwave radiating structure are sequentially connected, and the covering film structure covers the upper and lower surfaces of the microwave feeding structure, impedance matching network, and microwave radiating structure. The microwave feeding structure, impedance matching network, microwave radiating structure, and covering film structure are all made of flexible materials, and bending or stretching does not affect their function. They possess high-temperature resistance and can be inserted into the lungs via the trachea for ablation, reducing the risk of pneumothorax. Furthermore, its cross-sectional area is only 2.6mm*0.2355mm, which greatly reduces harm to the human body and meets the needs of most tumor ablation procedures.

Description

Technical Field

[0001] This invention belongs to the field of microwave ablation technology and relates to a microwave ablation antenna based on a flexible substrate integrated coaxial line. Background Technology

[0002] Microwave ablation, as the fifth major treatment for cancer, is gradually becoming an alternative to surgical resection due to its fewer complications, repeatability, and minimally invasive nature. Currently, microwave ablation technology is widely used in the treatment of liver cancer, bone cancer, and kidney tumors. Most current microwave ablation antennas are rigid coaxial microwave ablation needles that require percutaneous insertion. However, for different cancer treatments, such as lung cancer and liver cancer, a single ablation antenna may not be suitable. For example, for liver cancer, a percutaneously inserted rigid ablation antenna can achieve good therapeutic results, while for lung cancer, a rigid ablation antenna may increase the risk of pneumothorax. A flexible ablation antenna inserted through the trachea can significantly reduce the risk of pneumothorax during lung cancer ablation treatment. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a microwave ablation antenna based on a flexible substrate integrated coaxial line. The material used is a flexible material that is not only resistant to high temperature but also does not affect its function when bent or stretched. It can be inserted into the lung tumor area through the trachea to perform tumor ablation, reducing the risk of pneumothorax during ablation and adapting to the application needs of increasingly complex ablation scenarios.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0005] A microwave ablation antenna based on a flexible substrate integrated coaxial line includes a microwave feeding structure, an impedance matching network, a microwave radiating structure, and a covering film structure; the microwave feeding structure, the impedance matching network, and the microwave radiating structure are connected in sequence, and the covering film structure covers the upper and lower surfaces of the microwave feeding structure, the impedance matching network, and the microwave radiating structure.

[0006] Furthermore, the microwave feeding structure, impedance matching network, microwave radiation structure, and covering membrane structure are all made of flexible materials, and bending or stretching does not affect their function, and they have high temperature resistance.

[0007] Furthermore, the microwave feeding structure includes a microstrip line and a metal pillar, wherein the top of the metal pillar is connected to the microstrip line, which passes through the first dielectric layer and the second dielectric layer and is connected to the intermediate inner conductor layer, and the microstrip line is located above the first dielectric layer.

[0008] Furthermore, the diameter of the metal column is 0.3 mm.

[0009] Furthermore, the impedance matching network is a substrate-integrated coaxial cable structure, which includes a top metal layer, a bottom metal layer, an intermediate inner conductor layer, a first dielectric layer, a second dielectric layer, and metallized vias.

[0010] Furthermore, the first dielectric layer is located between the top metal layer and the intermediate inner conductor layer, and the second dielectric layer is located between the bottom metal layer and the intermediate inner conductor layer; the metallized via penetrates the top metal layer and the bottom metal layer.

[0011] Furthermore, the diameter of the metallized through-hole is 0.3 mm.

[0012] Furthermore, the microwave radiation structure is connected to the intermediate inner conductor layer, and its shape is a serpentine bend, which is made of conductive material.

[0013] Furthermore, the cover film structure includes a top cover film and a bottom cover film. The top cover film is located above the top metal layer, and the bottom cover film is located below the bottom metal layer, and is used to protect the inner structure.

[0014] Furthermore, the total thickness of the microwave ablation antenna is 0.2355 mm, and the cross-sectional area is 2.6 mm * 0.2355 mm.

[0015] Compared with the prior art, the present invention has the following advantages and beneficial effects:

[0016] (1) The present invention is made of flexible material, which does not affect its function when bent or stretched, and has high temperature resistance. During ablation, it can be inserted into the lung through the trachea, reducing the risk of pneumothorax caused by percutaneous ablation of rigid ablation antenna.

[0017] (2) The present invention has a small cross-sectional area, which is only 2.6mm*0.2355mm, reducing the harm to the human body when it is inserted for ablation, and it has a good ellipsoidal ablation range, which meets the needs of most tumor ablation.

[0018] The objectives, features, and advantages of the present invention will be further described below in conjunction with embodiments and with reference to the accompanying drawings. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the principle of the microwave ablation antenna based on a flexible substrate integrated coaxial line according to the present invention.

[0020] Figure 2 This is a front view of the microwave ablation antenna based on a flexible substrate integrated coaxial line according to the present invention.

[0021] Figure 3 This is an exploded view of the microwave ablation antenna based on a flexible substrate integrated coaxial line according to the present invention.

[0022] Figure 4 This is a simulation diagram of the radiation coefficient of the microwave ablation antenna based on a flexible substrate integrated coaxial line according to the present invention.

[0023] Figure 5 This is a temperature distribution diagram at 60°C for the microwave ablation antenna based on a flexible substrate integrated coaxial line according to the present invention. Detailed Implementation

[0024] like Figure 1 Principle block diagram and Figure 2 As shown in the front view, this embodiment is a microwave ablation antenna based on a flexible substrate integrated coaxial line, including a microwave feeding structure 1, an impedance matching network 2, a microwave radiating structure 3, and a covering film structure 4. The microwave feeding structure 1, the impedance matching network 2, and the microwave radiating structure 3 are connected in sequence. The covering film structure 4 covers the upper and lower surfaces of the microwave feeding structure 1, the impedance matching network 2, and the microwave radiating structure 3. The microwave feeding structure 1, the impedance matching network 2, the microwave radiating structure 3, and the covering film structure 4 are all made of flexible materials, and bending or stretching does not affect their function. They also have high temperature resistance.

[0025] like Figure 3 As shown in the exploded view, the microwave ablation antenna based on the flexible substrate integrated coaxial line in this embodiment has a total of seven layers, from top to bottom: top cover film 41, top metal layer 21, first dielectric layer 22, middle inner conductor layer 26, second dielectric layer 23, bottom metal layer 25, and bottom cover film 42. A metallized via 24 with a diameter of 0.3 mm penetrates the top metal layer 21 and the bottom metal layer 25, and is located on both sides of the first dielectric layer 22 and the second dielectric layer 23.

[0026] In this embodiment of the invention, the microwave feeding structure 1 includes a microstrip line 11 and a metal pillar 12, wherein the top of the metal pillar 12 is connected to the 50Ω microstrip line 11, which passes through the first dielectric layer 22 and the second dielectric layer 23 and is connected to the intermediate inner conductor layer 26. The microstrip line 11 is located above the first dielectric layer 22, and the diameter of the metal pillar 12 is 0.3mm.

[0027] In this embodiment of the invention, the impedance matching network 2 is a substrate integrated coaxial line structure, which includes a top metal layer 21, a bottom metal layer 25, an intermediate inner conductor layer 26, a first dielectric layer 22, a second dielectric layer 23, and a metallized via 24.

[0028] In this embodiment of the invention, the microwave radiation structure 3 is connected to the intermediate inner conductor layer 26, and its shape is a serpentine bend, which is a conductive material.

[0029] In this embodiment of the invention, the cover film structure 4 includes a top cover film 41 and a bottom cover film 42. The top cover film 41 is located above the top metal layer 21, and the bottom cover film 42 is located below the bottom metal layer 25. The cover film structure 4 covers the outermost part of the entire structure and plays a role in protecting the inner structure.

[0030] In this embodiment of the invention, the total thickness of the microwave ablation antenna is only 0.2355mm, and the cross-sectional area is only 2.6mm*0.2355mm.

[0031] like Figure 4 The figure shows the reflection coefficient S of the microwave ablation antenna based on a flexible substrate integrated coaxial line in pig liver in this embodiment. 11 Simulation results show that the resonance is at 2.45 GHz and the return loss is -27.6 dB, achieving a good matching effect and making full use of microwave energy.

[0032] like Figure 5 The above describes the temperature distribution results of the microwave ablation antenna based on a flexible substrate integrated coaxial line in pig liver according to this embodiment. The input power is 10W, the ablation time is 600s, and the profile temperature is 60℃. According to the profile temperature distribution, the ablation range of the microwave ablation antenna of this invention is ellipsoidal.

[0033] Those skilled in the art will recognize that the embodiments described herein are intended to help the reader understand the principles of the invention, and should be understood that the scope of protection of the invention is not limited to such specific statements and embodiments. Those skilled in the art can make various other specific modifications and combinations based on the technical teachings disclosed in this invention without departing from the scope of the invention, and these modifications and combinations are still within the scope of protection of this invention.

Claims

1. A microwave ablation antenna based on a flexible substrate integrated coaxial line, characterized in that: It includes a microwave feeding structure (1), an impedance matching network (2), a microwave radiation structure (3), and a covering film structure (4); the microwave feeding structure (1), the impedance matching network (2), and the microwave radiation structure (3) are connected in sequence, and the covering film structure (4) covers the upper and lower surfaces of the microwave feeding structure (1), the impedance matching network (2), and the microwave radiation structure (3); The microwave feeding structure (1) includes a microstrip line (11) and a metal pillar (12), wherein the top of the metal pillar (12) is connected to the microstrip line (11), passes through the first dielectric layer (22) and the second dielectric layer (23), and is connected to the intermediate inner conductor layer (26), and the microstrip line (11) is located above the first dielectric layer (22); The impedance matching network (2) is a substrate integrated coaxial line structure, which includes a top metal layer (21), a bottom metal layer (25), an intermediate inner conductor layer (26), a first dielectric layer (22), a second dielectric layer (23), and a metallized via (24). The first dielectric layer (22) is located between the top metal layer (21) and the middle inner conductor layer (26), and the second dielectric layer (23) is located between the bottom metal layer (25) and the middle inner conductor layer (26); the metallized via (24) penetrates the top metal layer (21) and the bottom metal layer (25) and is located on both sides of the first dielectric layer (22) and the second dielectric layer (23).

2. The microwave ablation antenna based on a flexible substrate integrated coaxial line according to claim 1, characterized in that: The microwave feeding structure (1), impedance matching network (2), microwave radiation structure (3), and covering membrane structure (4) are all made of flexible materials.

3. The microwave ablation antenna based on a flexible substrate integrated coaxial line according to claim 1, characterized in that: The diameter of the metal column (12) is 0.3 mm.

4. A microwave ablation antenna based on a flexible substrate integrated coaxial line according to claim 1, characterized in that: The diameter of the metallized through-hole (24) is 0.3 mm.

5. A microwave ablation antenna based on a flexible substrate integrated coaxial line according to claim 1 or 2, characterized in that: The microwave radiation structure (3) is connected to the intermediate inner conductor layer (26), and its shape is a serpentine bend, which is a conductive material.

6. A microwave ablation antenna based on a flexible substrate integrated coaxial line according to claim 1 or 2, characterized in that: The cover film structure (4) includes a top cover film (41) and a bottom cover film (42). The top cover film (41) is located above the top metal layer (21), and the bottom cover film (42) is located below the bottom metal layer (25).

7. A microwave ablation antenna based on a flexible substrate integrated coaxial line according to claim 1, characterized in that: The microwave ablation antenna has a total thickness of 0.2355 mm and a cross-sectional area of ​​2.6 mm * 0.2355 mm.

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