CN117861041B - A microcatheter - Google Patents

Abstract

The invention provides a microcatheter, which belongs to the technical field of microcatheters; the microcatheter comprises a handle and a catheter main body, wherein the handle is connected with the catheter main body, the catheter main body at least comprises an inner layer, an outer layer and a supporting layer arranged between the inner layer and the outer layer, a tubular reinforcing layer is arranged on the outer side wall of the outer layer of the catheter main body, a notch is arranged on the reinforcing layer, and the notch is discontinuously arranged on the reinforcing layer and is used for improving the torsion control performance of the catheter main body; mainly solves the technical problem that the prior microcatheter has slow response to torsion operation, which causes difficult operation.

Description

A microcatheter

Technical Field

The invention belongs to the technical field of microcatheters, and in particular relates to a microcatheter.

Background technique

In recent years, with the increasing number of patients suffering from cardiovascular, cerebrovascular and tumor diseases and the continuous rise in mortality, and the high disability rate, most patients are left with symptoms such as hemiplegia and aphasia, which has brought great challenges to clinical surgery.

Vascular intervention surgery has the advantages of less trauma, low reaction, and fast recovery. It also has targeted characteristics and can effectively treat vascular diseases. In some areas, it has become the preferred treatment for cardiovascular and cerebrovascular diseases. Vascular intervention refers to a method of diagnosing and treating lesions by puncturing blood vessels and inserting guidewires and catheters into the blood vessel cavity under the guidance of imaging equipment. Vascular intervention treatment technology is a relatively new treatment method that is suitable for arterial diseases, venous diseases, tumor diseases, etc.

The tube body of the existing microcatheter used in interventional surgery is generally composed of inner and outer polymer layers and a support layer fixedly attached and installed between the inner and outer polymer layers. The support layer is generally formed by weaving metal wires to support the microcatheter to form a pipeline structure. However, the support layer formed by weaving metal wires has insufficient supporting force during the microcatheter pushing process. In addition, slippage is easily generated between the metal wires. As a result, when the distal end of the microcatheter needs to be twisted during the surgical operation, the microcatheter experiences slow transmission of torsion control force and the distal end of the microcatheter cannot quickly respond to the proximal twisting operation, resulting in difficulty in the surgical operation.

Therefore, it is necessary to provide an improved technical solution to address the above-mentioned deficiencies in the prior art.

Summary of the invention

The object of the present invention is to provide a microcatheter to solve the technical problem that the existing microcatheter responds slowly to the twisting operation, resulting in difficulty in surgical operation.

In order to achieve the above-mentioned purpose, the microcatheter of the present invention provides the following technical solutions:

A microcatheter comprises a handle and a catheter body, wherein the handle is connected to the catheter body, the catheter body comprises at least an inner layer, an outer layer and a support layer arranged between the inner layer and the outer layer, a tubular reinforcement layer is arranged on the outer side wall of the outer layer of the catheter body, the reinforcement layer is provided with cuts for increasing the flexibility of the reinforcement layer, and the cuts are intermittently arranged on the reinforcement layer to increase the torsion controllability of the catheter body.

As a further optimized technical solution, the incision is arranged along the circumferential direction of the reinforcement layer and penetrates the reinforcement layer; a plurality of the incisions are arranged staggered along the axial direction of the reinforcement layer, and one incision is arranged in the same circumferential direction.

As a further optimized technical solution, the angle at which the incision extends along the circumferential direction of the reinforcement layer is approximately between 90° and 180°.

As a further optimized technical solution, expansion structures are provided at both ends of each incision.

As a further optimized technical solution, the hole expansion structure includes a bell-mouth section extending obliquely outward from two side walls of the incision and an equal-diameter section connected to the bell-mouth section, and the equal-diameter section continues to extend from the bell-mouth section toward one end away from the incision.

As a further optimized technical solution, the plurality of cutouts are arranged in a spiral winding along the reinforcement layer.

As a further optimized technical solution, the incision is in the shape of a straight line arranged along the axial direction and penetrating the reinforcement layer, and a plurality of the incisions are staggered along the axial direction of the reinforcement layer.

As a further optimized technical solution, the incision includes a first incision and a second incision, the first incision and the second incision are both arc-shaped and opened along the circumference of the reinforcement layer, the first incision and the second incision are staggered, the length of the first incision is greater than that of the second incision, and the first incision and the second incision are symmetrically arranged in two in the circumference.

As a further optimized technical solution, the ends of the first incision and the second incision are both provided with axial holes extending axially along the reinforcement layer.

As a further optimized technical solution, a soft elastic section is fixedly provided at the far end of the reinforcement layer, and the soft elastic section is made of TPU material.

Beneficial effects: The present invention provides a tubular reinforcement layer on the outer wall of the catheter body and arranges incisions on the reinforcement layer, so that the reinforcement layer increases the bending performance on the basis of increasing the overall support performance of the catheter body. In this way, the overall support of the catheter body no longer relies solely on the support layer woven with metal wires, but the torsion control performance of the catheter body is increased by the reinforcement layer, thereby facilitating the control of the microcatheter to easily reach the patient's lesion location; and because the reinforcement layer is an integral tube structure, the overall performance is better and the response time is shorter when subjected to torsion control force, thereby increasing the convenience of operation and improving the operating efficiency.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings constituting a part of the present application are used to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. Among them:

FIG1 is a schematic diagram of the overall structure of a microcatheter embodiment 1 of the present invention;

Fig. 2 is a cross-sectional view taken along the A-A direction in Fig. 1;

FIG3 is a schematic diagram of the structure of the reinforcement layer of the microcatheter embodiment 1 of the present invention;

FIG4 is a schematic diagram of an enlarged structure of the cutout of FIG3 ;

FIG5 is a schematic front view of the reinforcement layer structure of the microcatheter embodiment 2 of the present invention;

FIG6 is a perspective schematic diagram of the reinforcement layer structure of the microcatheter embodiment 2 of the present invention;

FIG7 is a schematic front view of the reinforcement layer structure of the microcatheter embodiment 3 of the present invention;

FIG8 is a three-dimensional schematic diagram of the reinforcing layer structure of the microcatheter embodiment 3 of the present invention;

FIG9 is a schematic front view of the reinforcing layer structure of the microcatheter embodiment 4 of the present invention;

FIG. 10 is a three-dimensional schematic diagram of the reinforcing layer structure of microcatheter embodiment 4 of the present invention.

In the figure: 1, handle; 2, catheter body; 201, inner layer; 202, outer layer; 203, support layer; 204, soft elastic section; 3, inner stress diffusion layer; 4, outer stress diffusion layer; 5, reinforcement layer; 501-504 respectively represent the incisions in different embodiments (wherein, the incision on the reinforcement layer of the first embodiment is 501, the incision of the second embodiment is 502, the incision of the third embodiment is 503, and the incision of the fourth embodiment is 504); 5011, bell-mouth section; 5012, equal-diameter section; 5041, axial hole.

Detailed ways

The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention belong to the scope of protection of the present invention.

In the description of the present invention, the terms "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and do not require that the present invention must be constructed and operated in a specific orientation. Therefore, they cannot be understood as limitations on the present invention. The terms "connected" and "connected" used in the present invention should be understood in a broad sense. For example, they can be fixed connections or detachable connections; they can be directly connected or indirectly connected through intermediate components. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments. It should be noted that the embodiments and features in the embodiments of the present invention can be combined with each other without conflict.

It should be further explained that, in the present invention, the "distal end" uniformly refers to the end away from the operator during the operation, and the "proximal end" is just the opposite, referring to the end close to the operator.

The present invention provides a microcatheter, which arranges a reinforcement layer on the outside of a catheter body of the microcatheter to increase the overall support of the catheter body, and opens an incision on the reinforcement layer to increase the flexibility of the reinforcement layer, so that the catheter body has better overall performance and shorter response time when subjected to torsion control force, thereby increasing the convenience of operation.

Example 1

As shown in Figures 1 and 2, a microcatheter includes a handle 1 and a catheter body 2. The handle 1 is connected to the catheter body 2 through an internal stress diffusion layer 3. An external stress diffusion layer 4 is provided outside the connection position between the internal stress diffusion layer 3 and the handle 1. The internal stress diffusion layer 3 and the external stress diffusion layer 4 facilitate the handle 1 to transmit the operating force to the catheter body 2, thereby facilitating the handle 1 to control the catheter body 2 to perform corresponding actions in the blood vessel.

Specifically, as shown in FIG. 2 and FIG. 3 , the catheter body 2 at least includes an inner layer 201 , an outer layer 202 , and a support layer 203 disposed between the inner layer 201 and the outer layer 202 , and the support layer 203 is a metal wire braided structure. Among them, the inner layer 201 is made of PTFE (i.e. polytetrafluoroethylene) material. The PTFE material makes the inner cavity of the catheter body 2 have good lubricity, thereby facilitating the passage of surgical instruments. Although the support layer 203 of the metal wire braided structure can make the catheter body 2 have a certain support, when the microcatheter establishes a pathway to reach the lesion location during the operation, it is sometimes necessary to cross complex and curved blood vessels. In this process, the microcatheter needs to change direction so that it can smoothly pass through the blood vessels to reach the lesion location. At this time, the microcatheter supported only by the support layer 203 of the metal wire braided structure often cannot respond quickly to torque. Therefore, in the present invention, a tubular reinforcement layer 5 is provided on the outer side wall of the outer layer 202 of the catheter body 2. The reinforcement layer 5 is made of nickel-titanium alloy and has certain elasticity and bending properties. The setting of the reinforcement layer 5 increases the support and integrity of the catheter body 2 as a whole, thereby making the catheter body 2 have a good torque response speed.

In order to further increase the flexibility of the reinforcing layer 5, a cutout 501 is arranged on the reinforcing layer 5. The purpose of setting the cutout 501 is to ensure that the reinforcing layer 5 has good bending performance on the basis of ensuring that the catheter body 2 has a certain support performance. However, it is obvious that not all cutouts 501 can achieve this invention purpose. For example, if the cutout 501 is continuously spirally opened on the reinforcing layer 5, so that the reinforcing layer 5 is a spiral spring-like structure, it is obvious that when a torque is given to the reinforcing layer 5, the torque will cause the reinforcing layer 5 to deform in the radial direction, and the response of the reinforcing layer 5 to the torque is not effectively increased. Therefore, in order to ensure that the reinforcing layer 5 has integrity while ensuring the increase of the torsion control of the catheter body 2, the cutout 501 needs to be intermittently arranged on the reinforcing layer 5.

In this embodiment, the cutout 501 is in an arc shape, and the cutout 501 is arranged along the circumferential direction of the reinforcement layer 5 and penetrates the reinforcement layer 5; a plurality of cutouts 501 are arranged staggered along the axial direction of the reinforcement layer 5, and one cutout 501 is arranged in the same circumferential direction, so that the overall performance of the reinforcement layer 5 is better, thereby ensuring good support performance of the reinforcement layer 5. In this embodiment, the angle of the cutout 501 extending along the circumferential direction of the reinforcement layer 5 is approximately between 90° and 180°. It should be noted here that this range does not include the end point value, so that good bending performance of the reinforcement layer 5 can be ensured.

Since the two circumferentially extending side walls of the incision 501 will move relative to each other when the catheter body 2 is axially bent, at this time, the side walls at both ends of the incision 501 are connected to the circumferentially extending side walls that move relative to each other. If the two ends of the incision 501 are end structures of equal diameter, under the support of the reinforcement layer 5 body, there will inevitably be micro-tension on the side walls at both ends of the incision 501. The existence of tension at both ends of each incision 501 will eventually affect the overall bending performance of the reinforcement layer 5 to a certain extent. In order to reduce the occurrence of this situation, expansion structures are provided at both ends of each incision 501.

As shown in FIG4 , the hole expansion structure includes a bell-mouth section 5011 extending obliquely outward from the two side walls of the incision 501 and an equal-diameter section 5012 connected to the bell-mouth section 5011, and the equal-diameter section 5012 continues to extend from the bell-mouth section 5011 to the end away from the incision 501. The existence of the hole expansion structure can make the reinforcement layer 5 better transmit force, and at the same time reduce the micro-tension at the end of the equal-diameter incision 501, that is, reduce the resistance to relative movement of the two circumferentially extending side walls when the incision 501 is opposite, thereby effectively increasing the bending performance of the reinforcement layer 5. In other embodiments, the hole expansion structure can also be a circular hole with a diameter greater than the width of the incision 501.

The overall addition of the reinforcement layer 5 to the catheter body 2 inevitably increases the hardness of the distal end of the catheter body 2. The distal end of the catheter body 2 guides the overall forward movement of the microcatheter during the operation. In order to prevent the distal end of the catheter body 2 with increased hardness from colliding with the blood vessel during the movement of the blood vessel and causing damage to the blood vessel, a soft elastic section 204 is fixedly provided at the distal end of the reinforcement layer 5. The soft elastic section 204 is made of TPU (i.e., polyurethane elastomer) material.

When the present invention is used in practice, a reinforcing layer 5 is arranged on the outside of the catheter body 2 of the microcatheter to increase the overall support of the catheter body 2, and intermittently arranged incisions 501 are opened on the reinforcing layer 5 to increase the flexibility of the reinforcing layer 5, so that the overall performance of the catheter body 2 is better when subjected to torsion control force, and the response time is shortened, so that the delivery of the instrument can be completed faster, which facilitates the surgical operation.

Example 2

In this embodiment, almost all structures of the microcatheter are the same as those of the embodiment 1, and the only difference is that the cutout 502 is a straight line arranged along the axial direction of the reinforcing layer 5, and the arrangement of the multiple cutouts 502 is spirally wound along the reinforcing layer 5, as shown in Figures 5 and 6. The multiple cutouts 502 form the reinforcing layer 5 into a hollow structure, so that the reinforcing layer 5 can ensure good bending performance while ensuring that the catheter body 2 has a certain support performance.

Example 3

In this embodiment, almost all structures of the microcatheter are the same as those of the embodiment 1, and the only difference is that the cutout 503 is a straight line shape arranged along the axial direction and penetrating the reinforcing layer 5, and a plurality of cutouts 503 are staggered along the axial direction of the reinforcing layer 5, as shown in Figures 7 and 8. The plurality of cutouts 503 form the reinforcing layer 5 into a hollow structure, so that the reinforcing layer 5 can ensure good bending performance on the basis of ensuring that the catheter body 2 has a certain support performance.

Example 4

In this embodiment, almost all structures of the microcatheter are the same as those of the embodiment 1, and the only difference is that the incision 504 includes a first incision and a second incision, and the first incision and the second incision are both arc-shaped and opened along the circumference of the reinforcing layer 5. The first incision and the second incision are staggered, and the length of the first incision is greater than that of the second incision. The first incision and the second incision are both symmetrically arranged in two incisions in the circumference. When the first incision and the second incision are opened, they are arranged near the positions where the ends of each other are opposite to each other. That is, for example, the relative positions of the ends of the two oppositely arranged first incisions are the main structure of the reinforcing layer 5, so it is inevitable that the bending performance near this position is lower than that of the position with the incision 504. In order to compensate for the bending performance of this position, the second incision is opened near this position. For the same reason, the first incision is arranged near the position where the end of the second incision is opposite. In this way, the occupancy rate of the incision 504 in the reinforcing layer 5 in the circumferential direction can be increased, so that the reinforcing layer 5 can ensure good bending performance on the basis of ensuring that the catheter body 2 has a certain support performance, as shown in Figures 9 and 10.

In order to further increase the bending performance of the reinforcing layer 5, an axial hole 5041 extending axially along the reinforcing layer 5 is provided at the ends of the first incision and the second incision. The axial hole 5041 can help the reinforcing layer 5 to transmit force better and make the microcatheter easier to twist.

Example 5

In this embodiment, almost all structures of the microcatheter are the same as those in Embodiment 1, with the only difference being that the reinforcement layer includes a plurality of sections from the proximal end to the distal end, and a form of incision can be provided on each section, that is, the above four embodiments can be combined with each other to form reinforcement layers having a variety of forms.

It should be understood that the above description is merely exemplary and the embodiments of the present application do not limit this.

The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are within the scope of protection of the pending claims of the present invention.

Claims (6)

1. A microcatheter, comprising a handle (1) and a catheter body (2), wherein the handle (1) is connected to the catheter body (2), and the catheter body (2) comprises at least an inner layer (201), an outer layer (202), and a support layer (203) arranged between the inner layer (201) and the outer layer (202), characterized in that a tubular reinforcement layer (5) is arranged on the outer side wall of the outer layer (202) of the catheter body (2), and the reinforcement layer (5) is provided with cutouts (501, 502, 503, 504), and the cutouts (501, 502, 503, 504) are intermittently arranged on the reinforcement layer (5) to increase the torsion controllability of the catheter body (2); The incisions (501, 502, 503, 504) have one or more of the following arrangements: a), the cutout (501) is arranged along the circumferential direction of the reinforcement layer (5) and penetrates the reinforcement layer (5); a plurality of the cutouts (501) are arranged staggered along the axial direction of the reinforcement layer (5), and one cutout (501) is arranged in the same circumferential direction; b), the cutout (502) is in the shape of a straight line arranged along the axial direction and penetrating the reinforcement layer (5), and the arrangement of the plurality of cutouts (502) is in the form of a spiral winding along the reinforcement layer (5); c) the cutout (503) is in the shape of a straight line arranged along the axial direction and penetrating the reinforcement layer (5), and a plurality of the cutouts (503) are staggered along the axial direction of the reinforcement layer (5); d), the incision (504) comprises a first incision and a second incision, the first incision and the second incision are both arc-shaped and opened along the circumference of the reinforcement layer (5), the first incision and the second incision are staggered, the length of the first incision is greater than that of the second incision, and two of the first incision and two of the second incision are symmetrically arranged in the circumference. 2. The microcatheter according to claim 1, characterized in that, when the arrangement mode of the incision (501) is a), the angle at which the incision (501) extends along the circumferential direction of the reinforcement layer (5) is between 90° and 180°. 3. The microcatheter according to claim 2, characterized in that both ends of each of the incisions (501) are provided with expansion structures. 4. The microcatheter according to claim 3, characterized in that the expansion structure comprises a bell-mouth section (5011) extending obliquely outward from two side walls of the incision (501) and a constant diameter section (5012) connected to the bell-mouth section (5011), and the constant diameter section (5012) continues to extend from the bell-mouth section (5011) toward one end away from the incision (501). 5. The microcatheter according to claim 1, characterized in that, when the arrangement mode of the incision (504) is d), the ends of the first incision and the second incision are both provided with an axial hole (5041) extending axially along the reinforcing layer (5). 6. The microcatheter according to any one of claims 1 to 5, characterized in that a soft elastic section (204) is fixedly provided at the distal end of the reinforcement layer (5), and the soft elastic section (204) is made of TPU material.