CN111671495A

CN111671495A - Take and to strengthen getting of barb of catching power and tie support

Info

Publication number: CN111671495A
Application number: CN202010697195.5A
Authority: CN
Inventors: 王昂; 王仕林
Original assignee: Guangzhou Chuangjing Medical Technology Co ltd
Current assignee: Guangzhou Yijie Medical Technology Co ltd
Priority date: 2020-07-20
Filing date: 2020-07-20
Publication date: 2020-09-18

Abstract

The invention discloses a bolt taking support with barbs for enhancing catching force, which comprises a mesh cage formed by an elastic wire mesh in a curling shape, wherein the elastic wire mesh comprises a plurality of elastic wires which are mutually intersected to form a plurality of mesh units, the formed mesh units comprise a plurality of 8-shaped mesh units, and the middle parts of two sides of each 8-shaped mesh unit in the width direction are provided with an inward circuitous part; the device comprises at least one 8-shaped grid unit, wherein an extending wire extends towards an inward roundabout part of the 8-shaped grid unit, the two extending wires are intersected to form a capture unit, and a developing point/developing block can be welded at the tail end of the capture unit. The invention aims to provide a thrombus-taking bracket with barbs for enhancing catching force, which is used for enhancing the catching effect on thrombus more reasonably, enhancing the supporting strength and avoiding the premature collapse and deformation of a net cage caused by bending force.

Description

Take and to strengthen getting of barb of catching power and tie support

Technical Field

The invention belongs to the field of interventional therapy instruments, and particularly relates to a thrombus removal support with barbs for enhancing catching force.

Background

Cerebral apoplexy is ischemic stroke caused by thrombus in cerebral vessels, and the sudden reduction or stop of blood flow of local blood supply arteries of cerebral tissues causes cerebral tissue ischemia and hypoxia in blood supply areas of the cerebral tissues to cause necrosis and softening of the cerebral tissues, and is accompanied with clinical symptoms and signs of corresponding parts, such as symptoms of nerve function loss of hemiplegia, aphasia and the like.

Currently, the clinical treatment for ischemic stroke mainly adopts drug thrombolysis and mechanical thrombus removal.

The disadvantages of drug thrombolysis are: is only suitable for thrombus with smaller volume, has poor treatment effect on thrombus embolism with large volume, and only 3 to 5 percent of patients are suitable for drug thrombolytic treatment; its thrombolysis effectiveness is less than one third. Furthermore, some patients have allergic reactions to thrombolytic drugs and are not suitable for thrombolytic therapy. For patients who exceed the thrombolysis time window and are intolerant of thrombolysis treatment, the mechanical thrombus removal method has a good clinical application effect.

The mechanical thrombus extraction is to convey the thrombus extraction support to a lesion position, suck and extract the thrombus from an occlusion area and capture the thrombus. The therapeutic device involved in capturing the thrombus comprises a micro catheter, a sheath tube, a micro guide wire, a balloon catheter, a thrombus removal bracket and the like. The thrombus taking bracket is the most key element for catching thrombus.

The embolectomy stents are generally mesh-cage shaped, consisting of a coiled, resilient wire mesh generally having a side near the distal end and a side near the proximal end. In order to overcome the problem that thrombus fragments are missed or fall halfway when the thrombus is caught, the technical personnel in the field have made some improvements. For example, the following are several prior patents relating to the overall structure of the embolectomy device and the enhanced capturing effect added inside the embolectomy device:

(1) CN201711466707.1 discloses a thrombus extractor having capturing rods for enhancing capturing effect on thrombus, any two of the capturing rods are different-surface rods, however, there is still no information about optimizing and improving the specific form of the capturing rods;

(2) US20190216476A1 discloses an embolectomy stent and an improved structure thereof, wherein a developing block is arranged at a part of the middle of a net cage where a plurality of silk ribbons are intersected, and the structure can also better prevent thrombus fragments from being lost in a diseased blood vessel during catching.

Although there are a number of prior patents which disclose more or less technical features for enhanced capture.

However, none of the above prior patents shows a better and more reasonable thrombus capture effect and a leakage prevention effect. Therefore, there is a need in the art for new solutions to achieve further attribute improvements.

Disclosure of Invention

In order to solve the technical problems reflected by the background technology, the invention aims to provide a thrombus taking support with barbs for enhancing the catching force, so as to more reasonably enhance the catching effect on thrombus. The specific scheme is as follows:

the area is strengthened grabbing of force of arresting's barb and is tied support, include the cylinder mould that is the curl form by elastic wire, elastic wire includes many elastic wires, and its characteristics can be: the elastic wires are mutually crossed to form a plurality of 8-shaped grid units, and the middle parts of two sides of each 8-shaped grid unit in the width direction are provided with an inward roundabout part; at least one 8-shaped grid unit is provided with extending filaments extending towards an inward roundabout part, and the two extending filaments are intersected to form a capturing unit.

Further, defining the 8-shaped grid unit with the capture unit as a first 8-shaped grid unit, and defining the 8-shaped grid unit without the capture unit as a second 8-shaped grid unit; the first 8-shaped grid units and the second 8-shaped grid units are arranged at intervals to form a plurality of rows of capture segments.

Further, each column of catching segments has catching units that are staggered by a gap in the axial direction.

Furthermore, the elastic wires are mutually intersected to form a plurality of quadrilateral grid units, and all the quadrilateral grid units form a plurality of rows of interval subsections.

Furthermore, each row of catching segments and each row of the spacing segments are arranged in a staggered mode to form a catching network segment close to the far end.

Further, the catching unit is in a herringbone structure extending obliquely towards the direction of the central axis of the net cage in a curling mode.

Further, a barb part of the herringbone structure, which is close to the far end, is welded with a first developing block.

Further, the side of the netpen is open or closed.

Further, when the side of the cylinder mould is open, the cylinder mould is provided with a first edge part and a second edge part which are positioned on the side, the first edge part is provided with a plurality of inwards concave deformation parts, and the second edge part is provided with a plurality of convex deformation parts which are in one-to-one correspondence with the inwards concave deformation parts.

Further, a second developing block is fixedly connected to the mesh cage near the distal end.

Compared with the prior art, the implementation of the invention has the beneficial effects that:

(1) the embolectomy support is additionally provided with a plurality of catching units in a specific shape, and the extending directions of all the catching units are inclined inwards, so that the catching force can be increased, the net cage is conveniently hidden in the micro-catheter before being unfolded, and the extrusion force and the friction force of the micro-catheter to the net cage in an extrusion state are reduced. Moreover, the catching units are distributed in a mutually different surface way, and the extending length and the extending angle are also reasonable, so that the catching capacity of thrombus is improved, the thrombus omission and escape are reduced, meanwhile, the condition that the catching units scratch the vascular wall can be avoided, the use is safer, and in addition, the invention can also play a better far-end protection effect.

(2) The catching unit is arranged at the roundabout part of the 8-shaped grid unit and is of a herringbone structure, catching force can be guaranteed, and the first 8-shaped grid unit and the second 8-shaped grid unit are beneficial to avoiding the dangerous situation that the net cage is subjected to overlarge bending force and is collapsed and deformed when being bent.

(3) The net cage is of an open-loop/open structure, namely a structure which can be bent to open and close to a certain degree, so that the net cage is favorable for adapting to slightly-changed diameters of different positions in a blood vessel, is made of a metal material with shape memory, can be collapsed and folded under a pressed condition in the blood vessel, has self-expansion recovery capability in a free state, and has good adherence property.

(4) The capturing unit is fixedly connected with a plurality of developing blocks at the tail end close to the far end, the second developing block is defined as a second developing block, the effect of conveniently observing the bending condition of the current cylinder mould can be achieved, and the mode is different from the mode that only a developing ring and a single developing block are arranged at one end of the cylinder mould close to the near end and one end close to the far end.

(5) Although the invention is mainly applied to clearing thrombus in cranial cerebral vessels, the invention does not exclude the opportunity of applying the invention to other parts of human bodies.

Drawings

Fig. 1 is a perspective view (frontal perspective) of the netpen of the present invention;

FIG. 2 is a perspective view (oblique two-sided view) of the netpen of the present invention;

FIG. 3 is a schematic view of an embodiment of the elastic web of the present invention after it has been unrolled;

FIG. 4 is a schematic diagram illustrating the embodiment of FIG. 3 in a corresponding section;

FIG. 5 is a schematic view of an elastic web according to another embodiment of the present invention after it has been unrolled;

FIG. 6 is a schematic diagram illustrating the embodiment of FIG. 5 in a corresponding section;

FIG. 7 is a schematic view of an elastic web according to yet another embodiment of the present invention after it has been unrolled;

fig. 8 is an explanatory view of the structure of the netpen taken close to it;

FIG. 9 is a schematic structural diagram of the 8-shaped grid cells;

fig. 10A is a schematic representation (max) of the change in the crimp of the netpen in a preferred embodiment of the invention;

fig. 10B is a schematic representation of the variation in the degree of curling of the netpen in a preferred embodiment of the invention (moderate);

fig. 10C is a schematic representation (minimum) of the variation in the crimp of the netpen in a preferred embodiment of the invention;

FIG. 11A is a schematic representation of the use of the netpen of the present invention prior to passage through a region of thrombus occlusion;

FIG. 11B is a schematic view of the use of the netpen of the present invention released after passage through a thrombus-occluded area and capturing thrombus;

FIG. 12 is a schematic structural view of another example of a circular arc structure different from the herringbone structure disclosed in FIG. 9.

Wherein, 100, a net cage; 101. flattening the elastic silk screen; 110. an inward circuitous portion; 111. a circular arc-shaped overlapping gap; 112. drawing wires; 113. a first edge portion; 114. a second edge portion; 115. a divergent network segment; 116. capturing a network segment; 1160. a first column of capture segments; 1161. a first column of spaced segments; 1162. a second row of capture segments; 1163. a second column of spaced segments; 1164. a third column captures the segment; 117. dislocation distance; 118. a quadrilateral mesh cell; 119. a first type 8 grid cell; 120. a second type 8 font grid cell; 121. an inwardly concave deformation portion; 122. a convex deformation portion; 123. the second developing speed; 200. a catching unit; 201. a first developing block; 300. an outer catheter; 301. a microcatheter; 400. a blood vessel; 401. thrombosis.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail below with reference to the accompanying drawings, embodiments and modifications. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

To more clearly describe the structure of the stent product disclosed herein, the meaning of the two concepts "distal" and "proximal" are defined herein, which are conventional terms in the field of interventional medical devices. Specifically, "distal" refers to the end of the procedure distal to the operator, and "proximal" refers to the end of the procedure proximal to the operator. Of course, for a single device object, the "proximal" end may also be defined as the end thereof closer to the operator, and the "distal" end may also be defined as the end thereof further from the operator.

In addition, for convenience of describing individuals such as each part and component, the present invention will be described using descriptions indicating positional relationships such as "left", "right", "front", "rear", "upper", "lower", and the like; in the present invention, the description with the serial numbers such as "first" and "second" is only used to distinguish the objects of description in principle, and does not refer to any meaning of importance distinction or arrangement distinction.

In addition, the present invention is described by taking an approximate form as an object, such as "8-shaped grid cell", which means that the grid cell has a form similar to an 8-shaped form, i.e., a grid form in which two sides are approximately circular and the middle part is narrowed to form two inwardly roundabout parts 110.

Referring to fig. 1-11B, a thrombectomy stent with barbs to enhance capture force, including but not limited to: the net cage 100 is formed by the elastic silk net in a curling shape, and the elastic silk net 101 presented after the net cage 100 is unfolded is made of memory material, such as nickel-titanium alloy. The elastic silk net comprises a plurality of elastic silks which are mutually intersected, so that a plurality of grid units are formed. The innovation point of the invention is that the capture unit 200 which is used for enhancing the capture effect and is arranged at the grid unit is optimized, and the detailed expression is as follows: a part of the grid cells are in a certain shape to form a plurality of 8-shaped grid cells, and the middle parts of two sides of each 8-shaped grid cell in the width direction are provided with an inward roundabout part 110; at least one 8-shaped grid unit has an extension wire extending towards the inner roundabout part 110, and the two extension wires are joined to form a capturing unit 200, which can be seen in fig. 9. Referring to fig. 1 and 2, details of the inside distribution of the capturing units 200 after the entire netpen 100 is curled can be reflected.

Referring to fig. 4 and 6, here, for convenience of description and understanding, and as a preferable scheme of shape and structure, the inventor defines the 8-shaped grid cells with the capturing units 200 as the first type 8-shaped grid cells 119; meanwhile, defining the 8-shaped grid cells without the capture unit 200 as the second type 8-shaped grid cells 120; the first type 8 grid cells 119 and the second type 8 grid cells 120 are spaced apart, such that a plurality of rows of capture segments are formed.

As a preferred embodiment, with reference to fig. 4 and 6, the catching units 200 of each row of catching segments are staggered by a gap in the axial direction, and finally the elastic wire net 101 will present a certain offset distance 117, which is beneficial to form catching units with different surfaces, avoiding catching dead angles and enhancing catching effect.

Of course, since the stent has a certain length, as a preferred embodiment, the elastic wires are intersected with each other to form a plurality of quadrilateral lattice units 118, the mentioned quadrilateral lattice units 118 do not belong to a parallelogram in geometric shape, and four edges of the quadrilateral lattice units can be one edge or a plurality of edges of the quadrilateral lattice units are in a curve shape, so that the stent is placed in a tightened state when being accommodated in the tube, and is also expanded when being released outwards. All quadrilateral grid cells 118 form a number of column-spaced segments. Each row of catching segments and each row of spacing segments are arranged in a staggered manner to form a catching network segment 116 close to the far end, and one end of the elastic silk net 101 close to the traction silk 112 is a diverging network segment 115.

Referring to fig. 3, the overall length of the elastic mesh 101 is defined as α, the length of the catching network segment 116 of the elastic mesh 101 is defined as β, and the diameter of the elastic mesh 101 is defined as θ; wherein, the value range of beta is about 20mm to 40mm, and the value range of theta is about 2.5mm to 6.0 mm.

As shown in fig. 9, the capturing unit 200 may have a herringbone structure extending obliquely in the direction of the central axis of the rolling of the netpen 100. Other shapes, such as an arc-shaped structure extending obliquely toward the central axis of the rolling of the netpen 100, are also possible, so that the possible scraping of the vessel wall by the tip position of the catching unit 200 can be avoided in case the catching unit protrudes from the outer wall of the netpen 100, as shown in fig. 12.

In order to facilitate the observation of the position and the shape of the bolt taking bracket in an X-ray environment, the barb of the herringbone structure close to the far end is welded with a first developing block 201. The material of the first developing block 201 may be platinum, gold, iridium, tantalum, or an alloy of platinum, gold, iridium, tantalum, or a combination thereof. If the capturing unit 200 is in the arc structure of fig. 12, a first developing block 201 in a tubular shape may be threaded on the top of the arc position, or a first developing block in a block shape may be fixed by bonding or welding.

In particular, the sides of the netpen 100 may be closed or open.

If the side of the netpen 100 is open, see fig. 1, 4, 6. The netpen 100 has a first edge portion 113 and a second edge portion 114 on the side, and the netpen 100 can adapt to blood vessels 400 with different diameters within a certain range, specifically, since the netpen 100 has a certain elasticity, when passing through the blood vessels 400, the self-curling degree can be adjusted according to the diameter changes of different blood vessels 400, and of course, the adaptation also has a certain range. The specific deformation mode can be seen in fig. 10A, 10B and 10C.

In particular, there may be a disadvantage that, for example, when the netpen 100 passes through a blood vessel 400 with a large degree of bending, because the netpen 100 is in an open or ring-opening structure, once a lateral supporting force is weak, the net may be instantaneously collapsed and deformed once the bending force is accumulated to a certain degree, thereby causing an dangerous situation. In response to the possible dangerous situation, it is preferable that the first edge 113 is provided with a plurality of concave deformations 121, and the second edge 114 is provided with a plurality of convex deformations 122 corresponding to the concave deformations 121. So set up, then can strengthen the circumference of getting the bolt support and support intensity, when avoiding receiving great bending force, the local position takes place to collapse the situation emergence of deformation in the twinkling of an eye.

In order to enable the end of the netpen 100 to be clearly viewed in an X-ray environment, a second developing block 123 is fixedly connected to the end of the netpen 100 near the distal end. Of course, the number of the second developing blocks 123 may be plural, and the second developing blocks are provided around the periphery of the end of the netpen 100 near the distal end. The second developing unit 123 is made of the same material as the first developing unit 201, and is fixedly connected by welding.

Referring to fig. 11A, the thrombus-removal stent with barbs at the crossing positions of the silk screen is hidden in an external microcatheter 301 and is not in a spread state in operation. Referring again to fig. 11B, the thrombus-retrieval stent having barbs at the intersection positions of the silk screen according to the present invention is in a use state of capturing thrombus 401. Finally, the embolectomy support with barbs at the crossed positions of the silk screen is required to be arranged in a therapeutic instrument and matched with other modules and/or parts for use during operation. Accordingly, the therapeutic apparatus should include, but not be limited to: the outer catheter 300, the hemostatic valve device, the sheath, the microcatheter 301, the pull wire 112, and the thrombectomy stent itself. The overall structure of the medical instrument is well known and does not form the invention of the present invention, and therefore, the present invention is not described in detail.

The above description is only for the purpose of illustrating preferred embodiments and variations of the present invention, and is not to be construed as limiting the invention, as 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. The area is strengthened grabbing of force's barb and is tied support of getting, includes the cylinder mould that is the curl form by elastic wire net, elastic wire net includes many elastic wires, its characterized in that: the elastic wires are mutually crossed to form a plurality of 8-shaped grid units, and the middle parts of two sides of each 8-shaped grid unit in the width direction are provided with an inward roundabout part; at least one 8-shaped grid unit is provided with extending filaments extending towards an inward roundabout part, and the two extending filaments are intersected to form a capturing unit.

2. The embolectomy stent with enhanced capture barbs of claim 1 wherein: defining the 8-shaped grid unit with the capture unit as a first 8-shaped grid unit, and defining the 8-shaped grid unit without the capture unit as a second 8-shaped grid unit; the first 8-shaped grid units and the second 8-shaped grid units are arranged at intervals to form a plurality of rows of capture segments.

3. The embolectomy stent with enhanced capture barbs of claim 2 wherein: the catching units of each row of catching segments are offset by a gap in the axial direction.

4. The embolectomy stent with enhanced capture barbs of claim 3 wherein: the elastic wires are mutually intersected to form a plurality of quadrilateral grid units, and all the quadrilateral grid units form a plurality of rows of interval subsections.

5. The embolectomy stent with enhanced capture barbs of claim 4 wherein: each row of catching segments and each row of the interval segments are arranged in a staggered mode to form a catching network segment close to the far end.

6. The embolectomy stent with enhanced capture barbs of claim 1 wherein: the catching unit is of a herringbone structure extending obliquely towards the curling central axis direction of the net cage.

7. The embolectomy stent with enhanced capture barbs of claim 6 wherein: the barb part of herringbone structure near the distal end is welded with a first developing block.

8. The embolectomy stent with enhanced capture barbs of claim 1 wherein: the side of the net cage is open or closed.

9. The embolectomy stent with enhanced capture barbs of claim 8 wherein: when the side of cylinder mould is open, the cylinder mould has first edge portion and second edge portion that is located the side, first edge portion is provided with a plurality of indent deformation portions, the second edge portion be provided with a plurality of with the protrusion deformation portion of indent deformation portion one-to-one.

10. The embolectomy stent with enhanced capture barbs of any of claims 1-9, wherein: the net cage is fixedly connected with a second developing block close to the far end.