Steep pulse ablation needle for minimally invasive treatment

Abstract

The invention relates to a steep pulse ablation needle for minimally invasive therapy, which comprises a handle for holding operation, an insulating sleeve is arranged at the front end of the handle in a penetrating manner, and ablation needles are distributed in the insulating sleeve along the axial direction, penetrate through the insulating sleeve and can move along the axial direction; the handle is also provided with a fixing ring, a roller, a pinion, a rack and a supporting seat; a pinion is coaxially mounted on the roller and is in meshed connection with the rack; the rack is fixedly connected with the supporting seat, and the supporting seat is connected with the ablation needle and can slide along a guide structure in the handle. And the fixing ring sleeves the outer side of the handle and is in sliding connection with the handle. And the fixing ring can slide to be clamped with or separated from the roller so as to limit or release the rotation of the roller. By means of precise meshing of the precise pinion and the rack, directional constraint of arc-shaped guide ribs on the two sides and tactile feedback design of a spherical protrusion structure and a positioning groove, reference control can be achieved, and the problem that the ablation range is inaccurate due to adjustment deviation is effectively solved.

Description

Technical Field

[0001] This invention relates to an ablation needle, and more particularly to a steep pulse ablation needle for minimally invasive treatment. Background Technology

[0002] Steep pulse therapy, with its targeted advantage of irreversible electroporation, has become an important technological direction for minimally invasive treatment of solid tumors, and related ablation needle devices have been effectively applied. For example, Chinese patent CN103876785B discloses a multifunctional needle for minimally invasive biopsy and ablation of solid tumors, which integrates biopsy and radiofrequency ablation through an inner cannula with attached electrodes, and can electrocoagulate hemostasis and aspirate lesion fluid. However, such devices have significant technical shortcomings: First, insufficient adjustment precision and large transmission gaps result in electrode exposure length adjustment errors exceeding ±0.5mm, making it difficult to meet the precise ablation needs of small lesions. Second, poor locking reliability, cumbersome operation, and easy loosening due to intraoperative vibration, leading to ablation needle displacement and affecting treatment efficacy. Third, limited clinical adaptability, unable to adapt to various solid tumors spanning 5-40mm, requiring frequent device changes and increasing surgical complexity.

[0003] In view of the above-mentioned shortcomings, the designer has actively researched and innovated in order to create a steep pulse ablation needle for minimally invasive treatment, making it more industrially valuable. Summary of the Invention

[0004] To address the aforementioned technical problems, the purpose of this invention is to provide a steep pulse ablation needle for minimally invasive treatment.

[0005] This invention discloses a steep pulse ablation needle for minimally invasive treatment, comprising a handle for gripping and operation, an insulating sleeve passing through the front end of the handle, and ablation needles axially distributed within the insulating sleeve, wherein: the ablation needles penetrate the insulating sleeve and are movable axially; the handle is also equipped with a fixing ring, a roller, a pinion, a rack, and a support base; a pinion is coaxially mounted on the roller, and the pinion meshes with the rack; the rack is fixedly connected to the support base, and the support base is connected to the ablation needles and can slide along a guide structure inside the handle; the fixing ring is sleeved on the outside of the handle and slidably connected to the handle; the fixing ring can slide to engage or disengage with the roller to restrict or release the rotation of the roller; the guide structure inside the handle and the support base form a double-sided constraint.

[0006] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, the pinion is a precision gear with a module of 0.1 to 0.4 mm and a number of teeth of 4 to 10, preferably with a module of 0.2 mm and a number of teeth of 8.

[0007] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, the surface of the handle is marked with a scale of 0-40mm, the scale is distributed along the sliding direction of the support, and a positioning groove is formed at 5mm intervals.

[0008] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, the side of the support base is connected to an elastically repositionable ball protrusion structure, a micro-spring is connected between the ball protrusion structure and the support base, and the ball protrusion structure is engaged with positioning grooves distributed on the handle.

[0009] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, the outer side of the roller is provided with a waist-shaped groove, and when the fixing ring slides to the position of the waist-shaped groove, it fits against the inner wall of the waist-shaped groove to form a locking engagement.

[0010] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, a portion of the roller protrudes from the outside of the handle, with the exposed length being 1 / 3 to 1 / 2 of the roller diameter, and the roller surface is covered with anti-slip textures.

[0011] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, after the fixing ring engages with the roller, the axial movement of the rack is ≤0.05mm.

[0012] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, the ablation needle is arranged parallel to the rack, and the tip of the ablation needle is a pointed needle-shaped electrode.

[0013] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, the ablation needle is connected to a cable for transmitting pulse energy. The cable is routed along the side of the support base and extends to the tail of the handle, where the tail of the handle is provided with clips for securing the cable.

[0014] Furthermore, in the aforementioned steep pulse ablation needle for minimally invasive treatment, the guide structure inside the handle is an arc-shaped guide rib, and the support seat is embedded between the arc-shaped guide ribs; the two ends of the connecting shaft between the roller and the pinion are supported and connected to the inner wall of the handle through bushings; a lubricating layer is distributed between the support seat and the arc-shaped guide rib, and the lubricating layer is a polytetrafluoroethylene layer.

[0015] By means of the above-described solution, the present invention has at least the following advantages: 1. Through the precise meshing of the pinion and rack, the directional constraint of the double-sided arc-shaped guide ribs, and the tactile feedback design of the ball protrusion structure and positioning groove, reference control can be achieved, effectively avoiding the problem of inaccurate ablation range caused by adjustment deviation.

[0016] 2. A linkage locking structure with an interference fit between the fixing ring and the roller's waist-shaped groove is adopted. When locked, the roller's rotation is directly restricted, making it less prone to loosening compared to independent locking structures. Locking and unlocking can be completed simply by axially sliding the fixing ring, without any additional operating steps. This simplifies the process, reduces the risk of accidental activation, and improves structural stability during surgery.

[0017] 3. The ablation needle exposure length adjustment range covers 0-40mm, which can be adapted to more than 85% of solid tumor lesions of different sizes. Unlike traditional fixed length or fixed spacing schemes, it does not require frequent instrument replacement, which not only reduces surgical preparation time and operational complexity, but also reduces the cost of instruments in clinical treatment.

[0018] 4. The handle has a non-slip surface and supports one-handed operation. The adjustment and locking process is simple and efficient, reducing the difficulty of operation in minimally invasive scenarios. All core components are made of medical-grade compliant materials, which can withstand multiple sterilization processes, extending their service life while avoiding the risk of component failure or tissue damage during surgery.

[0019] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the steep pulse ablation needle used for minimally invasive treatment.

[0021] Figure 2 yes Figure 1 A partially enlarged schematic diagram (including the ablation needle and insulating sleeve).

[0022] Figure 3 This is a schematic diagram of the internal structure of a steep pulse ablation needle used for minimally invasive treatment.

[0023] Figure 4 This is a schematic diagram of the engagement of a pinion and a rack.

[0024] The meanings of the labels in the figures are as follows.

[0025] Detailed Implementation The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0026] like Figures 1 to 3A steep pulse ablation needle for minimally invasive treatment includes a handle 3 for gripping and operation. An insulating sleeve 2 passes through the front end of the handle 3, and an ablation needle 1 is axially distributed within the insulating sleeve 2. Its unique feature is that the ablation needle 1 penetrates the insulating sleeve 2 and can move axially. The handle 3 also includes a fixing ring 4, a roller 5, a pinion 6, a rack 7, and a support base 8. Specifically, the ablation needle 1 uses a pointed needle-shaped electrode at its tip, which is arranged parallel to the rack 7 to ensure stable movement of the ablation needle 1 during adjustment and precise energy release. As an optimization, a titanium nitride coating with a thickness of 3-5 μm can be plated on the electrode surface, providing excellent conductivity, wear resistance, and resistance to bio-corrosion, preventing energy transmission fluctuations caused by electrode wear during surgery. Furthermore, the body of the ablation needle 1 can be made of medical-grade 316L stainless steel, precision ground to an outer diameter of 1.2-1.5 mm, ensuring smooth puncture and uniform energy distribution. During use, the ablation needle 1 is connected to a cable for transmitting pulse energy. The cable is a medical-grade silicone-sheathed multi-strand silver-plated copper wire cable. Its conductor cross-sectional area is 0.3 mm², insulation thickness is 0.5 mm, and temperature resistance range is -40℃ to 120℃. The cable is routed along a pre-set wiring groove on the side of the support base 8 and extends to the tail of the handle 3. Furthermore, the tail of the handle 3 is equipped with elastic buckles, and its inner side may have anti-slip protrusions. This securely holds the cable in place, preventing it from shifting during the procedure. To facilitate a stable, integrated connection, the ablation needle 1 and the support base 8 are bonded together with medical-grade epoxy adhesive, ensuring seamless power transmission.

[0027] In a preferred embodiment of the present invention, the insulating sleeve 2 is made of medical-grade polytetrafluoroethylene with a wall thickness of 0.8-1.2 mm. It is also bonded and fixed to the front end of the handle 3 using medical-grade anaerobic adhesive, ensuring that the insulating sleeve 2 remains fixed in position and does not move throughout the ablation process. The clearance between the front end of the insulating sleeve 2 and the exposed section of the ablation needle 1 is ≤0.1 mm. This allows for precise definition of the energy release area, preventing energy leakage into non-treatment areas and avoiding the risk of damage to normal tissue.

[0028] Furthermore, the handle 3 is integrally molded from medical-grade ABS material using an injection molding process. Its surface is knurled to create an anti-slip texture with a 1mm pitch and 0.2mm depth, enhancing grip friction. The handle 3 also features a clear 0-40mm scale with 0.2mm line width, achieved using laser engraving to a depth of 0.1mm. This scale is distributed along the sliding direction of the support base 8, forming a hemispherical positioning groove every 5mm, with a radius of 0.8mm and a depth of 0.5mm. Additionally, the inner wall of the handle 3 has two symmetrically distributed arc-shaped guide ribs with a semi-circular cross-section, a radius of 2mm, and a length of 45mm. These guide ribs are integrally injection molded with the handle 3 body. This serves as the internal guide structure of the handle 3, with the support base 8 embedded between the arc-shaped guide ribs, forming a double-sided constraint. The clearance between the guide ribs and the support base 8 is controlled at 0.03-0.05mm, ensuring the support base 8 slides without deviation and further improving adjustment stability.

[0029] In practical implementation, the retaining ring 4 can be made of medical-grade methyl vinyl silicone rubber, which has good elastic recovery and can be repeatedly deformed without easily failing. The retaining ring 4 is fitted onto the outside of the handle 3, with a fitting clearance of 0.05-0.1mm to ensure smooth sliding without radial wobble. Simultaneously, the inner side of the retaining ring 4 has an annular boss, 1.2mm wide and 0.6mm high. Correspondingly, the outer side of the roller 5 has a waist-shaped groove, 1.3mm wide and 0.7mm deep. Thus, when the retaining ring 4 slides axially along the handle 3 to the waist-shaped groove, the annular boss and the waist-shaped groove form an interference fit. The elastic deformation of the silicone rubber tightly adheres to the inner wall of the waist-shaped groove, directly restricting the rotation of the roller 5. When sliding in the reverse direction, the annular boss releases from the waist-shaped groove due to its own elasticity, unlocking the lock. Therefore, integrated control of adjustment and locking can be achieved without additional operating steps, avoiding the defects of cumbersome additional operation and accidental loosening.

[0030] The roller 5 used in this invention can be injection molded from medical-grade PC material, and its surface is provided with anti-slip texture. This anti-slip texture can be a uniform ring of raised bumps, with a height of 0.3-0.5mm and a spacing of 1mm, increasing friction during operation. Simultaneously, a portion of the roller 5 protrudes from the outside of the handle 3, with an exposed length of 1 / 3-1 / 2 of the roller 5's diameter, facilitating single-finger rotation adjustment by the doctor. The small gear 6 is made of medical-grade stainless steel with a precision-customized structure, featuring a module of 0.2mm, 8 teeth, a pressure angle of 20°, a tooth tip height coefficient of 1.0, and a clearance coefficient of 0.25. The connecting shaft between the small gear 6 and the roller 5 can be fixed by laser welding, with a coaxiality error ≤0.01mm, ensuring smooth transmission of rotational power. After meshing with the rack 7, it can precisely convert the rotational power of the roller 5 into the linear motion of the rack 7, providing a core guarantee for the high-precision adjustment of the ablation needle 1.

[0031] Furthermore, the rack 7 can be made of medical-grade titanium alloy, manufactured through wire cutting and precision grinding. Its tooth profile is precisely matched with the pinion 6, with a meshing clearance ≤0.02mm. Simultaneously, the rack 7 is fixed to the top surface of the support base 8 using a high-strength medical adhesive. As an optimization, the contact surfaces of the rack 7 and the support base 8 can be sandblasted before bonding to improve adhesion. The perpendicularity error between the rack 7 and the support base 8 is ≤0.03mm, ensuring accurate power transmission. The support base 8 is injection molded from medical-grade PPSU material, primarily providing stable support for the rack 7. Mounting holes are provided on the side of the support base 8, and an elastically resetting ball protrusion structure is installed inside. The body of the ball protrusion (usually spherical) is made of medical-grade zirconia ceramic with a diameter of 1.5mm. A micro-spring connects the body of the ball protrusion to the mounting hole of the support base 8. One end of the micro-spring abuts against the bottom of the mounting hole, and the other end pushes the body of the ball protrusion, keeping the body of the ball protrusion always extending outwards. Miniature springs can be made of medical-grade stainless steel wire with a diameter of 0.1mm, 5 turns, and a free length of 3mm.

[0032] During implementation, as the support base 8 slides, the ball protrusion engages with the corresponding hemispherical positioning groove on the handle 3 at 5mm intervals, providing clear tactile positioning feedback to the doctor. This assists the doctor in accurately determining the adjustment position of the ablation needle 1, avoiding visual reliance and solving the adjustment error problem caused by relying solely on visual judgment of scales in existing technologies. As an optimization, a polytetrafluoroethylene (PTFE) lubricating layer can be distributed between the arc-shaped guide ribs of the support base 8 and the handle 3. This coating, applied using a spraying process, has a thickness of 0.1-0.2mm, which further improves the smoothness of sliding and prevents wear caused by long-term use.

[0033] This invention allows for a support connection between the two ends of the connecting shaft and the inner wall of the handle 3 via medical-grade engineering plastic bushings. This reduces the frictional resistance when the roller 5 rotates, ensuring a smooth adjustment experience. Simultaneously, the cable clip at the tail of the handle 3 is injection-molded from medical-grade elastic plastic, with anti-slip protrusions on the inner side, accommodating cables of different diameters and preventing cable slippage after locking.

[0034] The working principle of this invention is as follows: Before use, the doctor, based on the size of the lesion (determined through imaging examinations), can hold the handle 3 with one hand and rotate the exposed roller 5 with their fingers. The roller 5 drives the coaxial pinion 6 to rotate. During this process, the pinion 6 meshes with the rack 7, converting the rotational power into the linear motion of the rack 7. Subsequently, the rack 7 drives the support base 8 and the ablation needle 1 to move axially along the arc-shaped guide rib, thereby adjusting the exposure length of the ablation needle 1. During the adjustment process, the scale on the surface of the handle 3 provides a visual reference, and the engagement feedback between the ceramic ball protrusion and the positioning groove assists the doctor in precise positioning. For example, when the lesion size is 12mm, it can be quickly adjusted to the 12mm mark, where the ball protrusion engages and is positioned.

[0035] After the ablation needle 1 is adjusted to the desired exposure length, slide the retaining ring 4 along the handle 3 axis so that its inner annular boss engages with the waist-shaped groove of the roller 5. The rotation of the roller 5 can be restricted by the interference fit, thereby locking the position of the rack 7 and the ablation needle 1. If adjustment is needed, the retaining ring 4 can be slid in the opposite direction to unlock, and the roller 5 can be rotated again for adjustment.

[0036] During the procedure, the cable is secured by a clip at the end of the handle 3. Energy is transmitted via the cable to the pointed electrode of the ablation needle 1, where it releases a steep pulse of energy. The insulating sleeve 2 defines the energy release area, enabling precise ablation of the lesion. The overall procedure is simplified, requiring no additional auxiliary tools and reducing the difficulty of operation in minimally invasive settings.

[0037] Furthermore, the orientations or positional relationships described in this invention are based on the orientations or positional relationships shown in the accompanying drawings. They are only for the purpose of facilitating the description of this invention and simplifying the description, and are not intended to indicate or imply that the device or structure referred to must have a specific orientation, or to operate in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0038] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A steep pulse ablation needle for minimally invasive treatment, comprising a handle (3) for gripping and operation, wherein an insulating sleeve (2) is provided at the front end of the handle (3), and ablation needles (1) are distributed axially within the insulating sleeve (2), characterized in that: The ablation needle (1) penetrates the insulating sleeve (2) and can move axially; the handle (3) is also equipped with a fixing ring (4), a roller (5), a pinion (6), a rack (7) and a support seat (8); A pinion (6) is coaxially mounted on the roller (5), and the pinion (6) meshes with the rack (7); The rack (7) is fixedly connected to the support base (8), the support base (8) is connected to the ablation needle (1), and can slide along the guide structure inside the handle (3); The fixing ring (4) is sleeved on the outside of the handle (3) and slidably connected to the handle (3); the fixing ring (4) can slide to engage or disengage from the roller (5) to limit or release the rotation of the roller (5); The guide structure inside the handle (3) and the support seat (8) form a double-sided constraint.

2. The steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: The pinion (6) is a precision gear with a module of 0.1 to 0.4 mm and a number of teeth of 4 to 10.

3. The steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: The surface of the handle (3) is marked with a scale of 0-40mm. The scale is distributed along the sliding direction of the support (8) and a positioning groove is formed every 5mm.

4. The steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: The side of the support base (8) is connected to an elastically reset ball protrusion structure. A miniature spring is connected between the ball protrusion structure and the support base (8). The small ball protrusion structure is engaged with the positioning grooves distributed on the handle (3).

5. A steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: The outer side of the roller (5) is provided with a waist-shaped groove. When the fixing ring (4) slides to the position of the waist-shaped groove, it fits against the inner wall of the waist-shaped groove to form a locking engagement.

6. The steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: The roller (5) has a portion of its area exposed outside the handle (3), with the exposed length being 1 / 3 to 1 / 2 of the roller diameter. The surface of the roller (5) is covered with anti-slip textures.

7. A steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: After the fixed ring (4) engages with the roller (5), the axial movement of the rack (7) is ≤0.05mm.

8. A steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: The ablation needle (1) is arranged in parallel with the rack (7), and the front end of the ablation needle (1) is a pointed needle-shaped electrode.

9. A steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: The ablation needle (1) is connected to a cable for transmitting pulse energy. The cable is routed along the side of the support base (8) and extends to the tail of the handle (3). The tail of the handle (3) is provided with clips to fix the cable.

10. A steep pulse ablation needle for minimally invasive treatment according to claim 1, characterized in that: The guide structure inside the handle (3) is an arc-shaped guide rib, and the support seat (8) is embedded between the arc-shaped guide ribs; the two ends of the connecting shaft between the roller (5) and the pinion (6) are supported and connected to the inner wall of the handle (3) through bushings; a lubricating layer is distributed between the support seat (8) and the arc-shaped guide rib, and the lubricating layer is a polytetrafluoroethylene layer.

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