CN211325299U

CN211325299U - Microcatheter capable of releasing polymer spring ring

Info

Publication number: CN211325299U
Application number: CN201921184336.2U
Authority: CN
Inventors: 解荡; 邵立强
Original assignee: Suzhou Hengrui Hongyuan Medical Technology Co ltd
Current assignee: SUZHOU HENGRUI JIALISHENG BIOMEDICAL TECHNOLOGY Co.,Ltd.
Priority date: 2019-07-25
Filing date: 2019-07-25
Publication date: 2020-08-25
Anticipated expiration: 2029-07-25

Abstract

The utility model discloses a micro-catheter capable of releasing a polymer spring ring, which comprises an outer catheter and an inner catheter arranged in the outer catheter, wherein a side catheter is arranged on the side wall of one end of the outer catheter; the inner catheter is flush with the proximal end of the outer catheter, the distal end of the inner catheter being shorter than the outer catheter; the inner part of the inner catheter forms a cavity for injecting liquid embolic agent; an outer cavity is formed between the inner catheter and the outer catheter, and the side catheter is communicated with the outer cavity and used for infusing physiological saline into the outer cavity; the interior of the outer catheter at the distal end of the inner catheter forms a mixing chamber for mixing the liquid embolic agent pushed in by the inner lumen and the physiological saline pushed in by the outer lumen; wherein the liquid embolic agent is composed of an EVOH mixture, a DMSO solvent and tantalum powder.

Description

Microcatheter capable of releasing polymer spring ring

Technical Field

The utility model relates to the technical field of medical instrument design, concretely relates to little pipe of polymer spring coil can release.

Background

Releasable coils are medical devices used in the treatment of arterial stenosis. Coil 1991 Guglielmi et al first reported GDC embolization to treat intracranial aneurysms. The far end of the GDC is a spring ring made of platinum-tungsten alloy, is connected with a stainless steel guide wire and can be directly sent into the aneurysm. The implanted portion of platinum-tungsten alloy is left thrombosed within the aneurysm by means of either mechanical or electrical detachment. The GDC spring ring is extremely soft, the adaptability of the coil to advance and retreat in the aneurysm is good, the throwing position is unsatisfied and can be readjusted, and the occlusion of the parent artery is not easy to occur.

To achieve higher density packing, coil manufacturers often design more coils with different gauge, wire diameter, and length. Or designing springs with different functions, such as a basket ring, a packing ring and a tail closing ring. Or may be designed as metal-bonded polymer-type coils, such as gel rings, ciliated rings, and the like. The purpose of providing coils of such different sizes, different functions, and different styles is to achieve higher packing density.

These coils do increase the packing density of the aneurysm. However, because metal coils tend to build up stress during packing, later release of stress creates a risk of internal pressure against the aneurysm wall. Thus, physicians often dare not to fill too much. Generally, the highest density packing with a metal coil will not exceed 40%.

SUMMERY OF THE UTILITY MODEL

In view of the problems set forth in the background art, the present invention provides a microcatheter for releasing a polymeric spring ring, the microcatheter comprising an outer catheter and an inner catheter disposed within the outer catheter, a side catheter disposed on a side wall of one end of the outer catheter; the inner catheter is flush with the proximal end of the outer catheter, the distal end of the inner catheter being shorter than the outer catheter;

the inner part of the inner catheter forms a cavity for injecting liquid embolic agent; an outer cavity is formed between the inner catheter and the outer catheter, and the side catheter is communicated with the outer cavity and used for infusing physiological saline into the outer cavity; the interior of the outer catheter at the distal end of the inner catheter forms a mixing chamber for mixing the liquid embolic agent pushed in by the inner lumen and the physiological saline pushed in by the outer lumen;

wherein the liquid embolic agent is composed of an EVOH mixture, a DMSO solvent and tantalum powder.

Preferably, the distal end of the outer catheter is provided with an outlet port through which the "noodle-like" polymeric coil is expelled after the liquid embolic agent is mixed with saline.

Preferably, a first input head is arranged at the proximal end of the micro-catheter, and the first input head is communicated with the inner cavity.

Preferably, one end of the side conduit is connected with the outer conduit, and the other end is provided with a second input head which is communicated with the outer cavity.

The utility model discloses owing to adopt above technical scheme, make it compare with prior art, have following advantage and positive effect:

1. the utility model designs a double-cavity (inner cavity and outer cavity) micro catheter, so that the near end of the micro catheter has a double-cavity structure of the inner cavity and the outer cavity, and the far end of the micro catheter has a single-cavity structure of a mixing cavity; through the arrangement of the side catheter, the inner cavity and the outer cavity simultaneously realize the injection of the liquid embolic agent and the normal saline, then the liquid embolic agent and the normal saline are mixed in the mixing cavity to form a micelle, and the noodle-shaped polymer spring ring is discharged from the output port at the far end of the microcatheter; the micro-catheter realizes the pre-mixing of the liquid embolic agent and the normal saline, and has simple structure and convenient operation;

2. the liquid embolic agent formed by the EVOH mixture, the DMSO solvent and the tantalum powder has no specification limit, and is not like a metal spring ring in the prior art, so that a plurality of specification models can be generated, and the polymer spring ring is more convenient to manufacture and lower in cost; the polymer spring ring can not release the packing stress, and the doctor can be relieved from packing; the packing density of the polymer coils is higher, theoretically 100% packing can be achieved.

Drawings

The above and other features and advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

fig. 1 is a schematic view of a microcatheter of the present invention that can release a polymeric coil.

Detailed Description

The invention will be described in more detail hereinafter with reference to the accompanying drawings showing embodiments of the invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, the size and relative sizes of layers and regions may be exaggerated for clarity.

Referring to fig. 1, the present invention provides a microcatheter capable of releasing a polymeric spring ring, the microcatheter comprising an outer catheter 1 and an inner catheter 2 disposed inside the outer catheter 1, a side catheter 3 disposed on a side wall of one end of the outer catheter 1; the inner catheter 2 is flush with the proximal end of the outer catheter 1, and the distal end of the inner catheter 2 is shorter than the outer catheter 1; the inner part of the inner catheter 2 forms a cavity 4 for injecting liquid embolic agent; an outer cavity 5 is formed between the inner catheter 2 and the outer catheter 1, and the side catheter 3 is communicated with the outer cavity 5 and is used for infusing physiological saline into the outer cavity 5; the interior of the outer catheter at the distal end of the inner catheter 2 forms a mixing chamber 6 for the mixing of the liquid embolic agent pushed in by the inner lumen 4 and the saline pushed in by the outer lumen 5.

Among them, liquid embolic agents composed of EVOH (ethylene/vinyl alcohol copolymer) mixture, DMSO (dimethyl sulfoxide) solvent and tantalum powder have been clinically used for tamponade of intracranial arteriovenous malformed blood vessels for over 20 years, so that their biosafety and effectiveness in tamponade of blood vessels have been well proven. The principle of solidification and solidification of the liquid embolic agent is physical precipitation, because DMSO can dissolve EVOH polymers, but the EVOH polymers are not dissolved in water or blood, when the DMSO solution of EVOH is contacted with water or blood, DMSO solvent can diffuse into water, and EVOH polymers can precipitate into solid micelles from the DMSO solvent.

The utility model takes the design as the basis and combines with the application of the micro catheter to design the micro catheter with double cavities (inner cavity and outer cavity); the proximal end of the microcatheter is provided with a double-cavity structure with an inner cavity and an outer cavity, the distal end of the microcatheter is provided with a single-cavity structure with a mixing cavity, the inner cavity and the outer cavity simultaneously realize the injection of the liquid embolic agent and the normal saline through the arrangement of the side catheter 3, then the liquid embolic agent and the normal saline are mixed in the mixing cavity to form a micelle, and the strip-shaped polymer spring ring is discharged from the output port at the distal end of the microcatheter. The micro-catheter realizes the premixing of the liquid embolic agent and the normal saline, and has simple structure and convenient operation.

The polymer spring ring formed in the utility model has no specification limit, unlike the metal spring ring in the prior art, which can generate a plurality of specification models, the polymer spring ring in the utility model has convenient manufacture and low cost; the polymer spring ring can not release the packing stress, and the doctor can feel relieved to pack; the packing density of the polymer spring ring is higher, and 100% packing can be realized theoretically; in addition, the polymer spring ring can be developed instantly because of the contained metal tantalum powder. The doctor uses the application method which is very close to the metal spring ring.

Furthermore, the shearing energy supply of the output spring ring can be realized by respectively controlling the speed of the fluid in the inner cavity and the outer cavity; for example, the flow rate of the liquid embolic agent in the outer cavity is improved, the flow rate of the inner fluid is reduced or stopped, and the cutting of the noodle-shaped spring ring formed by the outer cavity fluid and the inner cavity fluid gel can be realized, so that a tamping process is completed.

In this embodiment, the distal end of the outer catheter 1 is provided with an outlet port through which the "noodle-like" polymeric coil is expelled after the liquid embolic agent is mixed with saline. The size of the outlet opening is designed according to the size of the required polymer spring ring, and is not limited here.

In this embodiment, the proximal end of the microcatheter is provided with a first input tip 7; the first input head 7 is communicated with the inner cavity 4 so as to realize the injection of the liquid embolic agent into the inner cavity 4; in addition, the first inlet head 7 also seals off the proximal end of the outer chamber 5, as shown in fig. 1.

In this embodiment, one end of the side conduit 3 is connected and communicated with the outer conduit 1, and the side conduit 3 and the outer conduit 1 may be integrally formed or may be connected after being processed, which is not limited herein. The other end of the side catheter 3 is provided with a second input head 8, and the second input head 8 is communicated with the side catheter 3 and further communicated with the outer cavity 2 so as to convey the physiological saline into the outer cavity 2.

It will be appreciated by those skilled in the art that the invention can be embodied in many other specific forms without departing from the spirit or scope thereof. Although embodiments of the present invention have been described, it is to be understood that the present invention should not be limited to those precise embodiments, and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope or spirit of the invention as defined by the appended claims.

Claims

1. A microcatheter of releasable polymeric coils comprising an outer catheter and an inner catheter disposed within said outer catheter, said outer catheter having a side catheter disposed on a side wall at one end thereof; the inner catheter is flush with the proximal end of the outer catheter, the distal end of the inner catheter being shorter than the outer catheter;

2. The releasable polymeric coil microcatheter of claim 1, wherein the distal end of said outer catheter is provided with an outlet port through which the "noodle-like" polymeric coil is expelled upon mixing of the liquid embolic agent with saline.

3. The releasable polymeric coil microcatheter of claim 1, wherein a first input port is provided on the proximal end of the microcatheter, the first input port communicating with the lumen.

4. The releasable polymeric coil microcatheter of claim 1, wherein the side catheter has one end connected to the outer catheter and a second input disposed at the other end, the second input communicating with the outer lumen.