CN113018639A

CN113018639A - Preparation process of micro catheter capable of necking and bending

Info

Publication number: CN113018639A
Application number: CN202110245473.8A
Authority: CN
Inventors: 李敬伟; 董海林; 叶永红; 徐运; 罗云
Original assignee: Nanjing Drum Tower Hospital
Current assignee: Shanghai Xinwei Medical Technology Co ltd
Priority date: 2021-03-05
Filing date: 2021-03-05
Publication date: 2021-06-25
Anticipated expiration: 2041-03-05
Also published as: CN113018639B

Abstract

The invention discloses a preparation process of a miniature catheter capable of necking and bending, which comprises the steps of preparing a catheter body, preparing a traction tube, assembling the traction tube and the catheter body, installing an inner nut and an outer nut and a handle at one end of the catheter body, which is far away from a bell mouth, and connecting the two ends of a traction wire with the inner nut and the outer nut respectively, wherein the miniature catheter manufactured by the process can be adjusted in any direction at will so as to facilitate the miniature catheter to move in any direction in a tortuous blood vessel; the micro-catheter is matched with the handle for use, can control the angle within the angle range of 0-105 degrees, has the angle larger than 90 degrees, and can adapt to tortuous vessels of any shape; in addition, the microcatheter manufactured by the process can be manually necked down, so that the friction force is reduced when the microcatheter runs in a blood vessel, the harm caused by scraping thrombus on the blood vessel wall when the microcatheter runs in the blood vessel is avoided, the necking and the adjustable bending can be simultaneously carried out, and the friction force can be still reduced and the thrombus is prevented from sliding off when the microcatheter runs in the blood vessel.

Description

Preparation process of micro catheter capable of necking and bending

Technical Field

The invention relates to the technical field of medical instruments, in particular to a preparation process of a micro catheter capable of necking and bending.

Background

The micro-catheter is used for delivering an embolic agent to a vascular part in a patient body, during the process of opening the cerebral artery acute occlusion artery, the distal embolism protection is still blank, once the distal embolism occurs, the physical health of the patient is seriously damaged, the protection device of the micro-catheter on the market at present comprises a self-carried delivery catheter or a micro-catheter existing on the market for delivery, but no matter the self-carried delivery catheter or the micro-catheter existing on the market is used, the catheter has large outer diameter and poor trafficability, cannot be used for the opening protection of the acute aorta, the head end of the catheter is flat, thrombus on the vascular wall is easily scraped off and enters the distal end of a neurovascular to cause the blockage of the distal vascular to form cerebral infarction, in addition, when the catheter passes through a tortuous vascular, only the head end can be bent and plastic, but the bending and plastic property of the head end of the micro-catheter loaded with a thromboembolism protection system is very inconvenient, or cannot be performed, and in order to meet the requirements of the microcatheter, a preparation process of the microcatheter with the capability of necking and bending is urgently needed to solve the problems.

Disclosure of Invention

The invention provides a preparation process of a micro catheter capable of necking and bending.

In order to achieve the purpose, the invention provides the following technical scheme: a preparation process of a micro catheter capable of necking and bending comprises the following steps:

s1, preparing a pipe body, wherein the pipe body comprises an inner layer, a middle layer and an outer layer, and specifically comprises the following components:

a. preparing an inner layer, selecting powder, metering, sieving with a 200-mesh sieve, adding 15% petroleum ether as a boosting agent, mixing, curing for 2h, prepressing, extruding at 375-450 ℃, drying at 80 ℃ after extrusion, cutting a head end, and cutting the head end into a horn mouth shape by a die cutter;

b. preparing an intermediate layer, selecting round wires or flat wires, firstly carrying out heat treatment on the round wires or the flat wires at 510-502 ℃ for 10-12 min, and then weaving by adopting 1-to-1 or 1-to-2;

c. preparing an outer layer, selecting nylon powder, metering, sieving with a 200-mesh sieve, adding 20% paraffin oil as a boosting agent, mixing, curing for 2h, pre-pressing, extruding at the temperature of 150-275 ℃, and drying at the temperature of 60 ℃ after extrusion;

d. coating the inner layer with a film, sequentially sleeving the middle layer and the outer layer, and welding by hot air;

s2, preparing a traction tube, selecting a metal tube, cutting the metal tube into a partial coil tube by a femtosecond cutting machine, and penetrating a traction wire into the traction tube;

s3, assembling the traction pipe and the pipe body, and placing the traction pipe between the inner layer and the middle layer, wherein the coil pipe part corresponds to the bell mouth;

s4, installing an inner nut, an outer nut and a handle at one end of the pipe body far away from the bell mouth, and respectively connecting the two ends of the traction wire with the inner nut and the outer nut.

Preferably, the powder material is selected from PTFE particles with the code of F-201 when the inner layer is prepared, and the nylon powder material is selected from nylon 11 or nylon 12 when the outer layer is prepared.

Preferably, the inner layer and the outer layer are prepared, wherein the extrusion thickness is 0.0125mm to 0.075 mm.

Preferably, in step S1, hot-air welding the inner layer, the middle layer and the outer layer, specifically: firstly, penetrating an inner layer into a PTFE membrane, screwing the PTFE membrane at one end, clamping the screwed inner layer end with the membrane into a pneumatic chuck, and clamping the PTFE membrane at the other end by hemostatic forceps hung with hooks, wherein the temperature of a hot air welding nozzle is 235-255 ℃; the moving speed of the nozzle is 1.2 mm/s; then sleeving the middle layer on the inner layer, wherein the temperature of a hot air welding nozzle is 225-245 ℃; the moving speed of the nozzle is 1 mm/s; finally, sleeving the outer layer on the middle layer in a sleeving manner, wherein the temperature of a hot air welding nozzle is 215-235 ℃; the nozzle moving speed was 2 mm/s.

Preferably, in step S1, the round wire or flat wire of the middle layer is made of stainless steel material or nickel titanium material.

Preferably, in step S2, the pulling tube is made of a thin stainless steel tube.

Preferably, in step S2, the cutting rate is 3.8mm/S-4.2mm/S, the single pulse energy is 34.5UJ-35.5UJ, the working frequency is 200KHz, and the argon pressure is 11.8-12.2Bar when the cutting machine is femtosecond.

Preferably, in step S2, the pull tube is perforated with the lead perforation and the inner layer tailored projections aligned.

Preferably, in step S4, the inner and outer nuts are connected to the tube body and the handle by dispensing or curing.

Preferably, in step S4, the curing connection is a photo-curing process, wherein the transfer speed in the photo-curing process is 2 m/min.

Compared with the prior art, the invention has the beneficial effects that: the microcatheter manufactured by the process can be randomly adjusted in any direction so as to facilitate the microcatheter to advance in any direction in a tortuous blood vessel; the micro-catheter is matched with the handle for use, can control the angle within the angle range of 0-105 degrees, has the angle larger than 90 degrees, and can adapt to tortuous vessels of any shape;

in addition, the microcatheter manufactured by the process can be manually necked down, so that the friction force is reduced when the microcatheter runs in a blood vessel, the harm caused by scraping thrombus on the blood vessel wall when the microcatheter runs in the blood vessel is avoided, the necking and the adjustable bending can be simultaneously carried out, and the friction force can be still reduced and the thrombus is prevented from sliding off when the microcatheter runs in the blood vessel.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the principles of the invention and not to limit the invention.

In the drawings:

FIG. 1 is a schematic diagram of the construction of a microcatheter of the present invention;

FIG. 2 is a schematic structural view of a microcatheter of the present invention in a bent state;

FIG. 3 is a schematic structural view of a contracted state of a microcatheter of the present invention;

FIG. 4 is a flow diagram of a microcatheter fabrication process of the present invention;

FIG. 5 is a flow chart of a process for preparing the tube of the present invention;

reference numbers in the figures: 1. a pipe body; 11. an inner layer; 12. an intermediate layer; 13. an outer layer; 14. a bell mouth; 2. a traction tube; 21. a coil pipe; 22. a pull wire; 3. inner and outer nuts; 4. a handle.

Detailed Description

The preferred embodiments of the present invention will be described in conjunction with the accompanying drawings, and it will be understood that they are described herein for the purpose of illustration and explanation and not limitation.

As shown in fig. 1, the microcatheter manufactured by the process comprises a tube body, a traction tube arranged in the tube body and handles arranged at one end of the tube body, as shown in fig. 1-2, each handle operates a retractor so as to receive and release a traction wire connected with each handle, and each blade is controlled to swing under the traction of the traction wire, so that the head end can turn towards the expected direction as required, as shown in fig. 3, or under the simultaneous operation of a plurality of handles, one end of each blade far away from the tube body is controlled to be synchronously folded inwards to form a conical head end.

Example (b): as shown in fig. 4-5, a process for preparing a neckable, bendable microcatheter comprises the following steps:

s1, preparing a pipe body, wherein the pipe body comprises an inner layer, a middle layer and an outer layer;

as shown in fig. 5, the preparation of the inner layer, the intermediate layer and the outer layer specifically comprises:

a. preparing an inner layer, namely selecting powder, wherein the powder is selected from PTFE particles with the code of F-201, metering, sieving with a 200-mesh sieve, adding 15% petroleum ether serving as a boosting agent, mixing, curing for 2 hours, pre-pressing, extruding at the temperature of 375-450 ℃, drying at the temperature of 80 ℃ after extrusion, cutting a head end, and cutting the head end into a bell mouth shape by a die cutter, wherein four blades of the bell mouth are shown in fig. 3 in the embodiment, and the extrusion thickness is 0.0125mm-0.075mm according to different specification models;

b. preparing an intermediate layer, selecting round wires or flat wires, selecting stainless steel materials or nickel-titanium materials, firstly carrying out heat treatment on the round wires or the flat wires at 510-502 ℃ for 10-12 min, and then weaving by adopting 1-to-1 or 1-to-2;

c. preparing an outer layer, wherein nylon powder is selected, in the embodiment, the nylon powder is selected from nylon 11 or nylon 12, metering and sieving the nylon powder with a 200-mesh sieve, adding 20% paraffin oil as a boosting agent, mixing, curing for 2 hours, pre-pressing, extruding at the temperature of 150-275 ℃, and drying at the temperature of 60 ℃ after extruding, wherein the extrusion thickness is 0.0125mm-0.075mm according to different specifications and models;

d. with the inlayer tectorial membrane, cup joint intermediate level and skin in proper order to through hot-blast welding, specifically be: firstly, penetrating an inner layer into a PTFE membrane, screwing the PTFE membrane at one end, clamping the screwed inner layer end with the membrane into a pneumatic chuck, and clamping the PTFE membrane at the other end by hemostatic forceps hung with hooks, wherein the temperature of a hot air welding nozzle is 235-255 ℃; the moving speed of the nozzle is 1.2 mm/s; then sleeving the middle layer on the inner layer, wherein the temperature of a hot air welding nozzle is 225-245 ℃; the moving speed of the nozzle is 1 mm/s; finally, sleeving the outer layer on the middle layer in a sleeving manner, wherein the temperature of a hot air welding nozzle is 215-235 ℃; the moving speed of the nozzle is 2mm/s

S2, preparation traction tube chooses for use the tubular metal resonator, and in this embodiment, the tubular metal resonator chooses for use the component of thin stainless steel tube material, becomes partial coil through femto second cutting machine cutting, penetrates the traction wire in the traction tube, and wherein, when utilizing femto second cutting machine cutting, femto second cutting machine cutting parameter is: the cutting rate is 3.8mm/s-4.2mm/s, the single pulse energy is 34.5UJ-35.5UJ, the working frequency is 200KHz, the argon gas pressure is 11.8-12.2Bar, the traction tube is perforated, and the perforated part of the guide tube is aligned with the cutting protruding part of the inner layer;

s4, installing an inner nut, an outer nut and a handle at one end, far away from the bell mouth, of the tube body, connecting two ends of the traction wire with the inner nut and the outer nut respectively, and connecting the inner nut and the outer nut in a dispensing or curing mode when the inner nut and the outer nut are installed and a hand is installed.

Finally, it should be noted that: although the present invention has been described in detail with reference to the foregoing embodiments, it will be apparent to those skilled in the art that changes may be made in the embodiments and/or equivalents thereof without departing from the spirit and scope of the invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A preparation process of a micro catheter capable of necking and bending is characterized by comprising the following steps:

2. A process for preparing a neckable, bendable microcatheter as claimed in claim 1, wherein: when the inner layer is prepared, the powder material selects PTFE particles with the code number of F-201, and when the outer layer is prepared, the nylon powder material selects nylon 11 or nylon 12.

3. A process for preparing a neckable, bendable microcatheter as claimed in claim 1, wherein: and preparing an inner layer and an outer layer, wherein the extrusion thickness is 0.0125mm-0.075 mm.

4. A process for preparing a neckable, bendable microcatheter as claimed in claim 1, wherein: in step S1, hot air welding the inner layer, the middle layer and the outer layer, specifically: firstly, penetrating an inner layer into a PTFE membrane, screwing the PTFE membrane at one end, clamping the screwed inner layer end with the membrane into a pneumatic chuck, and clamping the PTFE membrane at the other end by hemostatic forceps hung with hooks, wherein the temperature of a hot air welding nozzle is 235-255 ℃; the moving speed of the nozzle is 1.2 mm/s; then sleeving the middle layer on the inner layer, wherein the temperature of a hot air welding nozzle is 225-245 ℃; the moving speed of the nozzle is 1 mm/s; finally, sleeving the outer layer on the middle layer in a sleeving manner, wherein the temperature of a hot air welding nozzle is 215-235 ℃; the nozzle moving speed was 2 mm/s.

5. A process for preparing a neckable, bendable microcatheter as claimed in claim 1, wherein: in step S1, the round wire or the flat wire of the middle layer is made of stainless steel or nickel titanium.

6. A process for preparing a neckable, bendable microcatheter as claimed in claim 1, wherein: in step S2, the traction tube is made of a thin stainless steel tube.

7. A process for preparing a neckable, bendable microcatheter as claimed in claim 1, wherein: in step S2, when the cutting machine is a femtosecond cutting machine, the cutting rate is 3.8mm/S-4.2mm/S, the single pulse energy is 34.5UJ-35.5UJ, the working frequency is 200KHz, and the argon pressure is 11.8-12.2 Bar.

8. A process for preparing a neckable, bendable microcatheter as claimed in claim 1, wherein: in step S2, the pull tube is perforated with the lead perforation portions aligned with the inner layer trim tabs.

9. A process for preparing a neckable, bendable microcatheter as claimed in claim 1, wherein: in step S4, the inner and outer nuts are connected to the tube body and the inner and outer nuts are connected to the handle by dispensing or curing.

10. A process for preparing a neckable, tunable microcatheter as claimed in claim 9, wherein: in step S4, the curing connection is used by a photo-curing process in which the transfer speed is 2 m/min.