CN215688389U - Microwave ablation needle - Google Patents

Abstract

The utility model discloses a microwave ablation needle, which comprises a needle point, an outer needle tube, a coaxial cable, a radiator, a water guide tube and a spiral choke ring, wherein the coaxial cable, the water guide tube and the outer needle tube are coaxially sleeved from inside to outside in sequence, gaps are respectively reserved between the water guide tube and the coaxial cable as well as between the water guide tube and the outer needle tube, the outer needle tube comprises a ceramic outer needle tube and a metal outer needle tube, the ceramic outer needle tube is fixedly connected with the needle point and the metal outer needle tube respectively, the spiral choke ring is a metal film laid on the outer surface of the ceramic outer needle tube, the needle tube is electrically communicated with the metal outer needle tube, the radiator is fixedly connected with an inner conductor of a coaxial cable or integrally formed, the radiator is located in a tube cavity of the ceramic outer needle tube close to the needle point, the water guide tube comprises a PTEF water guide tube and a metal water guide tube, the PTEF water guide tube is coaxially connected with the metal water guide tube, the PTEF water guide tube is partially or completely located in the tube cavity of the ceramic outer needle tube, and the metal water guide tube is located in the tube cavity of the metal outer needle tube. Can inhibit the microwave from escaping to the far end of the needle tip, fully cool the needle tip and improve the clinical effect.

Description

Microwave ablation needle

Technical Field

The utility model relates to the technical field of microwave treatment equipment, in particular to a microwave ablation needle.

Background

In recent years, with the development and progress of modern science and technology and oncology, domestic microwave tumor treatment makes effective breakthrough, and microwave ablation is gradually one of important treatment means of liver cancer. The microwave ablation is to accurately puncture a microwave ablation antenna to lesion tissues to be ablated through the skin by using modern imaging medicine (B ultrasound/CT/MRI) as an auxiliary puncture technical means, and apply microwave energy with certain power and certain frequency (usually 900-2500MHz) to the lesion tissues to be ablated. The characteristic that polar molecules (water molecules, protein molecules and carbohydrate molecules) and charged particles in the pathological tissue generate heat under the action of high-speed oscillation, friction and collision of a microwave alternating electric field is utilized, so that the pathological tissue is heated (>41 ℃) to denature and necrose, the treatment aim is achieved, and meanwhile, the temperature of adjacent healthy tissue cells is kept lower than the temperature of irreversible cell damage.

The mainstream ablation needle form in the market at present does not adopt any choking technology, and the radiation section is filled with a medium with high dielectric constant, and the technology causes the following problems: 1. the energy loss is large; 2. the choke technology is not applied, the microwave escapes along the direction of the distal end of the coaxial needle point, and the ablation form is deflected to be ellipsoidal; 3. the water circulation can not reach the needle tip of the ablation needle for cooling, so that the temperature of the needle tip of the ablation needle is too high, the tissue near the needle tip is carbonized after ablation, and even the needle tip is possibly burst to generate medical accidents.

SUMMERY OF THE UTILITY MODEL

In order to solve the problems that the energy loss of the existing ablation needle is large, the ablation form is biased to be ellipsoidal, the temperature of the needle tip is high, and the tissue near the needle tip is carbonized, the utility model innovatively provides a microwave ablation needle.A spiral choke ring is arranged outside an outer needle tube to inhibit an electric field escaping from the direction away from the needle tip, ensure that the electric field distribution presents a better spherical-like shape, and finally form a good spherical-like ablation form; the arrangement of the water conduit enables cooling water to circularly extend to the needle point part, so that the needle point and the outer needle tube are fully cooled, the possibility of carbonization of ablation tissues at the periphery of the needle point and the outer needle tube is greatly reduced, and the clinical effect is improved.

In order to achieve the technical purpose, the utility model discloses a microwave ablation needle, which comprises a needle point, an outer needle tube, a coaxial cable, a radiator, a water conduit and a spiral choke ring,

the coaxial cable, the water conduit and the outer needle tube are coaxially sleeved from inside to outside in sequence, gaps are arranged between the water conduit and the coaxial cable and between the water conduit and the outer needle tube,

the outer needle tube comprises a ceramic outer needle tube and a metal outer needle tube, the head end of the ceramic outer needle tube is fixedly connected with the needle point or integrally formed, the tail end of the ceramic outer needle tube is coaxially and fixedly connected with the metal outer needle tube, the spiral choke ring is a metal film laid on the outer surface of the ceramic outer needle tube, the spiral choke ring is in conductive communication with the metal outer needle tube,

the radiator is fixedly connected with the inner conductor of the coaxial cable or integrally formed, the radiator is positioned in the tube cavity of the ceramic outer needle tube close to the needle point,

the water diversion pipe comprises a PTEF water diversion pipe and a metal water diversion pipe, the PTEF water diversion pipe is coaxially connected with the metal water diversion pipe, the PTEF water diversion pipe is partially or completely positioned in the pipe cavity of the ceramic outer needle tube, and the metal water diversion pipe is positioned in the pipe cavity of the metal outer needle tube.

Further, the spiral choke ring is a soft magnetic ferrite thin film.

Furthermore, the radiator is a copper cap, the needle point is a ceramic needle point, and the copper cap is in riveting connection or welding connection with the inner conductor of the coaxial cable.

Furthermore, the radiator is a pole core, the pole core is welded with the inner conductor of the coaxial cable or integrally formed, the needle point is a metal needle point, and the pole core is in contact with the needle point.

Furthermore, the needle point is provided with an axial center blind hole, and the pole core is inserted into the center blind hole.

Furthermore, the coaxial cable comprises an inner conductor, a dielectric layer and an outer conductor which are sequentially sleeved from inside to outside, wherein the non-overlapped part of the dielectric layer and the outer conductor is positioned in the cavity of the ceramic outer needle tube.

Further, the metal outer needle tube is integrally formed by stainless steel.

Furthermore, the outer wall of the tail end of the ceramic outer needle tube is circumferentially provided with a step part, and the head end of the metal outer needle tube is sleeved on the step part.

Furthermore, the tail end of the metal outer needle tube is connected with a handle, a water inlet cavity and a water outlet cavity which are mutually independent are arranged in the handle, the water inlet cavity is communicated with the metal water diversion tube, and the water outlet cavity is communicated with the metal outer needle tube.

The utility model has the beneficial effects that:

according to the microwave ablation needle, the spiral choke ring is arranged outside the outer needle tube, so that an electric field escaping from the direction away from the needle point is inhibited, the electric field distribution is ensured to be in a better spherical-like shape, and a good spherical-like ablation form is finally formed; the arrangement of the water conduit enables cooling water to circularly extend to the needle point part, so that the needle point and the outer needle tube are fully cooled, the possibility of carbonization of ablation tissues at the periphery of the needle point and the outer needle tube is greatly reduced, and the clinical effect is improved.

Drawings

FIG. 1 is a schematic structural view of a microwave ablation needle according to a first embodiment of the present invention;

FIG. 2 is a longitudinal cross-sectional view of a microwave ablation needle in accordance with a first embodiment of the present invention;

FIG. 3 is a schematic structural view of a microwave ablation needle in accordance with a second embodiment of the present invention;

fig. 4 is a longitudinal sectional view of a microwave ablation needle in accordance with a second embodiment of the present invention.

In the figure, the position of the upper end of the main shaft,

1. a needle tip; 2. an outer needle tube; 3. a coaxial cable; 4. a radiator; 5. a water conduit; 6. a helical choke ring; 7. a handle; 21. a ceramic outer needle tube; 22. a metal outer needle tube; 31. an inner conductor; 32. a dielectric layer; 33. an outer conductor; 51. a PTEF water conduit; 52. a metal water conduit; 71. a water inlet cavity; 72. a water outlet cavity.

Detailed Description

The microwave ablation needle provided by the utility model is explained and explained in detail in the following with the attached drawings of the specification.

As shown in fig. 1-4, the present embodiment specifically discloses a microwave ablation needle, which includes a needle tip 1, an outer needle tube 2, a coaxial cable 3, a radiator 4, a water conduit 5, and a spiral choke ring 6, wherein the coaxial cable 3, the water conduit 5, and the outer needle tube 2 are coaxially sleeved in sequence from inside to outside, and gaps are present between the water conduit 5 and the coaxial cable 3, and between the water conduit 5 and the outer needle tube 2. The radiator 4 is used for emitting microwaves, the coaxial cable 3 transmits the microwaves generated by the microwave generator to the radiator 4, and the spiral choke ring 6 is used for restraining an electric field escaping away from the needle tip 1. The gap between the water conduit 5 and the coaxial cable 3 forms a water inlet channel, the gap between the water conduit 5 and the outer needle tube 2 forms a water outlet channel, and cooling water entering from the water inlet channel is used for cooling the needle point 1.

As shown in fig. 1 to 4, the outer tube 2 includes a ceramic outer tube 21 and a metal outer tube 22, and the metal outer tube 22 is integrally formed of stainless steel. The head end of the ceramic outer needle tube 21 is fixedly connected with the needle point 1 or integrally formed, and the tail end of the ceramic outer needle tube 21 is coaxially and fixedly connected with the metal outer needle tube 22. The ceramic outer needle tube 21 communicates with the lumen of the metal outer needle tube 22. In this embodiment, a step portion is circumferentially disposed on an outer wall of a tail end of the ceramic outer needle tube 21, and a head end of the metal outer needle tube 22 is sleeved on the step portion. The ceramic outer needle tube 21 and the metal outer needle tube 22 may be bonded and fixed by an adhesive. An adhesive storage groove may be provided on the step portion. The water conduit 5 penetrates through the tube cavities of the ceramic outer needle tube 21 and the metal outer needle tube 22, the water conduit 5 is located outside the radiator 4, a certain gap exists between the head end of the water conduit 5 and the inner wall of the needle point 1, and the gap can ensure that cooling water can contact with the inner wall of the needle point 1 when water enters the water conduit and passes through the gap.

The spiral choke ring 6 is a metal film laid on the outer surface of the ceramic outer needle tube 21, and the spiral choke ring 6 is in conductive communication with the metal outer needle tube 22. In a preferred embodiment, the spiral choke ring 6 is a thin film of soft magnetic ferrite. The spiral choke ring 6 is laid on the outer surface of the ceramic outer needle tube 21, equivalently, an inductor with a large inductance value is loaded, and the high-frequency current can be effectively prevented from being transmitted to the direction far away from the needle point 1 along the outer surface of the coaxial cable 3, so that the microwave is prevented from escaping to the direction far away from the needle point 1. The spiral choke ring 6 is a metal film, the thickness of the film is as small as possible, the film is preferably set to be 1-2 mm, damage to skin during puncture is avoided, and complications are reduced. More preferably, the length of the spiral choke ring 6 is the same as that of the ceramic outer tube 21, and the tail end of the spiral choke ring 6 contacts the metal outer tube 22, so that the microwave escaping along the direction of the distal end of the coaxial needle tip 1 is suppressed to the maximum extent, and the loss of the microwave energy when being emitted to the outside is reduced.

The coaxial cable 3 comprises an inner conductor 31, a dielectric layer 32 and an outer conductor 33 which are sleeved from inside to outside in sequence, wherein the head end of the inner conductor 31 is exposed outside the dielectric layer 32 in a certain length, the head end of the dielectric layer 32 is exposed outside the outer conductor 33 in a certain length, the part of the dielectric layer 32 exposed outside the outer conductor 33 is a non-overlapping part of the dielectric layer 32 and the outer conductor 33, and the non-overlapping part is positioned in a tube cavity of the ceramic outer needle tube 21 and is a radiation window.

The radiator 4 is fixedly connected with or integrally formed with the inner conductor 31 of the coaxial cable 3, the radiator 4 is positioned in the cavity of the ceramic outer needle tube 21 close to the needle point 1, the inner conductor 31 transmits the microwave to the radiator 4, and the radiator 4 emits the microwave.

In a first embodiment, as shown in fig. 1 and 2, the radiator 4 is a copper cap, the tip 1 is a ceramic tip, and the copper cap is riveted or soldered to the inner conductor of the coaxial cable 3. The needle tip 1 may be integrally formed with the ceramic outer needle cannula 21.

In the second embodiment, as shown in fig. 3 and 4, the difference from the first embodiment is: the radiator 4 is a pole core, the pole core is welded or integrally formed with the inner conductor 31 of the coaxial cable 3, when in actual production, the pole core can be the foremost part of the inner conductor 31, the needle point 1 is a metal needle point, and the pole core is in contact with the needle point 1. Further, as shown in fig. 4, the needle tip 1 is provided with an axial central blind hole, and the pole core is inserted into the central blind hole and can be bonded and fixed by an adhesive. The tail end of the needle point 1 can be provided with a step part along the circumferential direction, the ceramic outer needle tube 21 is sleeved on the step part, and the needle point and the ceramic outer needle tube are adhered and fixed through adhesive. Other structures of the second embodiment are the same as those of the first embodiment.

The water conduit 5 comprises a PTEF (polytetrafluoroethylene) water conduit 51 and a metal water conduit 52, the PTEF water conduit 51 is coaxially connected with the metal water conduit 52, and the PTEF water conduit 51 and the metal water conduit 52 are sleeved and connected and are fixedly bonded through an adhesive to form a water circulation pipeline together. The PTEF water conduit 51 is partially or completely positioned in the tube cavity of the ceramic outer needle tube 21, and the metal water conduit 52 is positioned in the tube cavity of the metal outer needle tube 22 and completely positioned outside the tube cavity of the ceramic outer needle tube 21. The metal water conduit 52 is completely positioned outside the tube cavity of the ceramic outer needle tube 21, and does not interfere with the radiation effect of the radiation window.

The tail end of the metal outer needle tube 22 is connected with a handle 7, a water inlet cavity 71 and a water outlet cavity 72 which are mutually independent are arranged in the handle 7, the water inlet cavity 71 is communicated with the metal water diversion tube 52, and the water outlet cavity 72 is communicated with the metal outer needle tube 22. The handle 7 is provided with a water inlet interface and a water outlet interface, the water inlet interface is communicated with the water inlet cavity 71, and the water outlet interface is communicated with the water outlet cavity 72.

Temperature sensors can be arranged in the water inlet cavity 71 and the water outlet cavity 72, a connecting terminal is arranged on the handle 7, the temperature sensors are connected with a computer or other instruments with calculation and display functions through the connecting terminal, the temperature of inlet water and outlet water is displayed, and the temperature of inlet water is controlled according to the temperature of outlet water.

According to the utility model, the spiral choke ring 6 is arranged, so that microwaves escaping along the direction of the far end of the coaxial needle point 1 can be inhibited, the loss of microwave energy during outward emission is reduced, the form of an emitted electric field is further promoted to tend to be circular, the ablation form effect is further improved, the water circulation can reach the head position of the needle point 1, the area is fully cooled, and a more circular and larger ablation form is created.

Microwave energy emitted by the microwave generator is transmitted to the radiation window (namely, the non-overlapped area of the dielectric layer 32 of the coaxial cable 3 and the outer conductor 33 of the coaxial cable 3) through the coaxial cable 3, and is radiated outwards from the radiation window, and finally, an electric field distribution is formed on the outer peripheries of the needle tip 1 and the outer needle tube 2, so that the ablation work is carried out on the tissues around the needle tip 1 and the outer needle tube 2.

However, since the metal outer needle tube 22, the metal water conduit 52 and the outer conductor 33 of the coaxial cable 3 are made of metal materials, part of the microwave electric field escapes from the direction away from the needle point 1, and the formed electric field is irregular in shape (i.e. cannot reach a sphere-like state), and finally, the tissue shape ablated at the periphery is irregular and cannot reach a sphere-like shape; at this time, the spiral choke ring 6 effectively inhibits the electric field escaping from the direction away from the needle tip 1, ensures that the electric field distribution presents a better spherical-like shape, and finally forms a good spherical-like ablation form.

Secondly, due to the heating effect of the electric field, the needle tip 1 and the outer needle tube 2 are heated to a very high temperature, and finally, the ablation tissues around the needle tip 1 and the outer needle tube 2 are carbonized seriously, which is not beneficial to the recovery of the patient in the later period. The utility model can ensure that the circulating water completely extends to the head part of the needle point 1, fully cools the needle point 1 and the outer needle tube 2, greatly reduces the possibility of carbonization of ablation tissues at the periphery of the needle point 1 and the outer needle tube 2 and improves the clinical effect.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the utility model and to simplify the description, and are not intended to indicate or imply that the referenced devices or elements must have a particular orientation, be constructed and operated in a particular orientation, and are therefore not to be considered limiting of the utility model.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description herein, references to the description of the term "the present embodiment," "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the utility model, and any modifications, equivalents and simplifications made in the spirit of the present invention are intended to be included in the scope of the present invention.

Claims (9)

1. A microwave ablation needle is characterized by comprising a needle point (1), an outer needle tube (2), a coaxial cable (3), a radiator (4), a water conduit (5) and a spiral choke ring (6),

the coaxial cable (3), the water conduit (5) and the outer needle tube (2) are sequentially and coaxially sleeved from inside to outside, gaps exist between the water conduit (5) and the coaxial cable (3) and between the water conduit (5) and the outer needle tube (2),

the outer needle tube (2) comprises a ceramic outer needle tube (21) and a metal outer needle tube (22), the head end of the ceramic outer needle tube (21) is fixedly connected with the needle point (1) or integrally formed, the tail end of the ceramic outer needle tube (21) is coaxially and fixedly connected with the metal outer needle tube (22), the spiral choke ring (6) is a metal film laid on the outer surface of the ceramic outer needle tube (21), the spiral choke ring (6) is in conductive communication with the metal outer needle tube (21),

the radiator (4) is fixedly connected with an inner conductor (31) of the coaxial cable (3) or integrally formed, the radiator (4) is positioned in a tube cavity of the ceramic outer needle tube (21) close to the needle point (1),

the water conduit (5) comprises a PTEF water conduit (51) and a metal water conduit (52), the PTEF water conduit (51) is coaxially connected with the metal water conduit (52), part or all of the PTEF water conduit (51) is positioned in a tube cavity of the ceramic outer needle tube (21), and the metal water conduit (52) is positioned in the tube cavity of the metal outer needle tube (21).

2. A microwave ablation needle according to claim 1, characterized in that the helical choke ring (6) is a thin film of soft magnetic ferrite.

3. The microwave ablation needle according to claim 1, characterized in that the radiator (4) is a copper cap, the needle tip (1) is a ceramic needle tip, and the copper cap is riveted or welded with the inner conductor of the coaxial cable (3).

4. A microwave ablation needle according to claim 1, characterized in that the radiator (4) is a pole piece welded or integrally formed with the inner conductor (31) of the coaxial cable (3), the needle tip (1) being a metal needle tip, the pole piece being in contact with the needle tip (1).

5. A microwave ablation needle according to claim 4, characterized in that the needle tip (1) is provided with an axial central blind hole, into which the pole piece is inserted.

6. The microwave ablation needle according to claim 1, wherein the coaxial cable (3) comprises an inner conductor (31), a dielectric layer (32) and an outer conductor (33) which are sleeved from inside to outside, and the non-overlapped part of the dielectric layer (32) and the outer conductor (33) is positioned in the lumen of the ceramic outer needle tube (21).

7. The microwave ablation needle according to claim 1, wherein the metallic outer needle tube (22) is integrally formed of stainless steel.

8. The microwave ablation needle according to claim 1, wherein a step is circumferentially arranged on the outer wall of the tail end of the ceramic outer needle tube (21), and the head end of the metal outer needle tube (22) is sleeved on the step.

9. The microwave ablation needle according to claim 1, characterized in that a handle (7) is connected to the tail end of the metal outer needle tube (22), an inlet cavity (71) and an outlet cavity (72) which are independent of each other are arranged in the handle (7), the inlet cavity (71) is communicated with the metal water conduit (52), and the outlet cavity (72) is communicated with the metal outer needle tube (22).

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