Tissue expansion catheter with fixing structure

Abstract

The invention relates to the technical field of medical instruments, in particular to a tissue expansion catheter with a fixing structure. Comprising an outer pipe and an inner pipe, the inner pipe is arranged in the outer pipe, the end of the outer pipe is fixedly connected with a communicating piece fixedly connected with the inner pipe, the communicating piece is fixedly connected with an outer expansion cylinder and an inner expansion cylinder, the outer expansion cylinder, the inner expansion cylinder and the inner expansion cylinder jointly form a filling cavity, and the inner expansion cylinder is fixedly connected with inner supporting bodies which are annularly distributed and make contact with the inner pipe. The side, away from the inner pipe, of the inner supporting body penetrates through the expansion inner cylinder and is provided with two sets of protrusions which are symmetrically distributed. The inner side of the expansion outer cylinder is pulled by the protrusions, so that pits are formed in the expanded surface of the expansion outer cylinder, then when the expansion outer cylinder expands and extrudes a lesion position, lesion tissue is embedded into the pits in the surface of the expansion outer cylinder, sliding of the expansion outer cylinder due to extrusion is restrained, and the expansion effect is improved. Meanwhile, the surface smoothness of the expansion outer cylinder in the folded state is kept, and movement of the expansion outer cylinder in the body of the patient is facilitated.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of medical devices, in particular to a tissue expansion catheter with a fixing structure. BACKGROUND

[0002] Balloon catheter is a key interventional medical device, which is usually used to expand the narrow or blocked part in blood vessels; its basic working principle is to restore the blood flow channel by applying radial force to the blood vessel wall through the inflation balloon; since the balloon part of the balloon expansion catheter is usually a smooth balloon, in the process of blood vessel expansion, if a calcified lesion with hard texture is encountered, the conventional balloon is prone to displacement during the pressurization process due to extrusion, thereby deviating from the target position, resulting in the inability to effectively expand the blood vessel. In order to solve this problem, in recent years, a papillary balloon with multiple papillary structures distributed on the surface has appeared; these papillae can increase the friction between the balloon and the lesion, play a role in preventing slipping, and ensure that the balloon does not move when expanding the blood vessel.

[0003] However, the papillary structure of the conventional papillary balloon is directly arranged on the surface of the balloon; although it increases the friction between the balloon and the lesion when the balloon is inflated, it also increases the surface roughness of the balloon when it is retracted, which is not conducive to the movement of the balloon catheter in the patient's body. Such rough surface can increase the resistance when passing through the tortuous blood vessels during catheter delivery, and even cause endothelial injury or spasm; in addition, the increase in roughness can also increase the friction between the catheter and the delivery system, affecting the operation feeling and positioning accuracy, and in severe cases, it may even cause the balloon to be difficult to reach the intended lesion position. SUMMARY

[0004] The present application provides a tissue expansion catheter with a fixing structure to overcome the shortcomings of conventional papillary balloons, which have high surface roughness and are not convenient to move in blood vessels.

[0005] The technical scheme is as follows: a tissue expansion catheter with a fixing structure, comprising: an outer tube and an inner tube, the inner tube is arranged in the outer tube, the end of the outer tube is fixedly connected with a communication member fixedly connected with the inner tube, the communication member is fixedly connected with an expansion outer cylinder and an expansion inner cylinder, and the three together form a filling cavity, the expansion outer cylinder is fixedly connected with the expansion inner cylinder away from the communication member, the expansion inner cylinder is fixedly connected with an inner support body which is annularly distributed and in contact with the inner tube, the inner support body away from the inner tube passes through the expansion inner cylinder and is provided with two groups of protrusions which are symmetrically distributed, each group of protrusions is equidistantly distributed, the protrusions are fixedly connected with the expansion outer cylinder, and are used for pulling the expansion outer cylinder to form a pit on the surface of the expansion outer cylinder when the expansion outer cylinder is inflated, the inner support body and the expansion inner cylinder together form a support cavity, the expansion inner cylinder is provided with arc-shaped holes which are annularly distributed, the number of the arc-shaped holes is equal to the number of the inner support body, and the support cavity is communicated with the filling cavity through adjacent arc-shaped holes.

[0006] Further, the arc-shaped hole is located on the side of the expansion inner tube away from the communication member.

[0007] Further, the communication member, the expansion outer tube and the expansion inner tube are all hydrophilic materials, which facilitates the gas in the filling cavity to be pressed into the support cavity.

[0008] Further, the communication member is provided with annularly distributed flow-through holes for blood flow.

[0009] Further, the number of the flow-through holes is equal to the number of the inner support bodies, and all the inner support bodies and all the flow-through holes are staggered.

[0010] Further, the end of the inner tube is fixedly connected with a mounting cylinder, the mounting cylinder is fixedly connected with annularly distributed guide pieces, the guide pieces are fixedly connected with the expansion outer tube, and the guide pieces are used to guide the movement of the expansion outer tube in the blood vessel.

[0011] Further, the guide pieces are made of elastic material, and when the expansion outer tube and the expansion inner tube are inflated, the guide pieces are in a stretched state, and when the expansion outer tube and the expansion inner tube are contracted, the guide pieces are in a free state.

[0012] Further, the number of the guide pieces is equal to the number of the flow-through holes, and all the flow-through holes and all the guide pieces are staggered.

[0013] Further, the side of the cross section of the mounting cylinder away from the expansion outer tube is arc-shaped.

[0014] Further, the outer side of the expansion outer tube, the inner side of the expansion inner tube and the outer side of the inner support body are all coated with a PTFE coating to inhibit platelet adhesion.

[0015] The beneficial effects produced by the above technical scheme are that the invention uses the traction of the protrusions on the inner side of the expansion outer tube to make the surface of the expansion outer tube after inflation have pits, and then when the expansion outer tube is inflated and pressed against the lesion site, the lesion tissue is embedded in the pits on the surface of the expansion outer tube, thereby inhibiting the sliding of the expansion outer tube caused by the pressing, and at the same time maintaining the smoothness of the surface of the expansion outer tube in the contracted state, which is beneficial to the movement of the expansion outer tube in the patient's body.

[0016] The gaps of all the inner support bodies and the flow-through holes provide a flow channel for blood, avoiding the blockage of the blood vessel by the balloon inflation, thus prolonging the time of single inflation and improving the expansion effect on the lesion site.

[0017] The guiding piece pulls the expansion outer tube, so that the expansion outer tube can be close to the surface of the inner tube when being folded, and then the expansion outer tube is uniformly folded, so that the maximum outer diameter of the balloon catheter in the folded state is controlled, and the balloon catheter is convenient to move in the patient's body. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a schematic diagram of the three-dimensional structure of the present application; Figure 2 It is a schematic diagram of the three-dimensional structure of the present application; Figure 3 It is a schematic diagram of the three-dimensional structure of the present application; Figure 4 It is a schematic diagram of the three-dimensional structure of the present application; Figure 5 It is a schematic diagram of the three-dimensional structure of the present application; Figure 2 It is an enlarged view of A in the figure; Figure 6 It is an exploded view of the present application.

[0019] Figure label name: 1, outer tube, 2, inner tube, 3, communication piece, 301, flow hole, 4, expansion outer tube, 5, expansion inner tube, 501, filling cavity, 502, arc hole, 6, inner support, 601, protrusion, 602, support cavity, 7, mounting tube, 8, guiding piece. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be described clearly and completely below in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0021] Embodiment 1

[0022] The present application provides a tissue expansion catheter with a fixed structure to reduce the moving resistance of the balloon catheter in the patient's body.

[0023] The current papillary balloon catheter has a rough surface in the folded state due to the papillary structure on the surface, which is not conducive to the movement of the balloon catheter in the patient's body.

[0024] Referring to Figures 1 to 4 and Figure 6The utility model provides a kind of tissue expansion catheter with fixed structure, comprising: outer tube 1 and inner tube 2, inner tube 2 is arranged in outer tube 1, inner tube 2 is used for the guide wire to pass through, outer tube 1 and inner tube 2 constitute delivery channel, and above-mentioned delivery channel is communicated with external pressure pump, and contrast medium is injected into delivery channel by pressure pump;The end of the left side of outer tube 1 is fixedly connected with communicating piece 3, communicating piece 3 is made of inner and outer double-layer circular table cylinder, so there is inner ring and outer ring in the end surface of communicating piece 3, the inner ring of the right part of communicating piece 3 is fixedly connected with inner tube 2, so that delivery channel is communicated with the inside of communicating piece 3;The outer ring and inner ring of the left side of communicating piece 3 are fixedly connected with expansion outer cylinder 4 and expansion inner cylinder 5 respectively, the left side of expansion outer cylinder 4 is fixedly connected with the left side of expansion inner cylinder 5, communicating piece 3, expansion outer cylinder 4 and expansion inner cylinder 5 jointly constitute filling cavity 501, expansion inner cylinder 5 is fixedly connected with the three inner support bodies 6 of annular distribution, and inner support body 6 and expansion inner cylinder 5 jointly constitute support cavity 602, expansion inner cylinder 5 is provided with the three arc-shaped holes 502 of annular distribution, support cavity 602 is communicated with filling cavity 501 by adjacent arc-shaped hole 502, inner support body 6 is contacted with inner tube 2, when inner support body 6 is inflated, its inner side is abutted with inner tube 2, to provide support to expansion outer cylinder 4 and expansion inner cylinder 5;The side of inner support body 6 away from inner tube 2 passes through expansion inner cylinder 5 and is provided with two groups of protrusions 601 of symmetrical distribution, and there are several equidistant distribution in each group of protrusions 601, and protrusion 601 is fixedly connected with expansion outer cylinder 4, and the number and interval of protrusion 601 here are determined by the axial length of expansion outer cylinder 4 and the flexibility of its material, for traction expansion outer cylinder 4 when expansion outer cylinder 4 is inflated to make its surface form pit (see Figure 1 ).

[0025] The above setting can realize, using protrusion 601 to traction the inside of expansion outer cylinder 4, so that the surface of expansion outer cylinder 4 after inflation produces pit, and then when expansion outer cylinder 4 is inflated and extruded to pathological position, make pathological tissue embed in the pit on the surface of expansion outer cylinder 4, and then inhibit the sliding of expansion outer cylinder 4 from extrusion, and keep the smoothness of the surface of expansion outer cylinder 4 in the state of folding, which is beneficial to the movement of expansion outer cylinder 4 in patient's body.

[0026] In the process that pressure pump injects contrast medium into filling cavity 501 through delivery channel, contrast medium gradually fills filling cavity 501 and support cavity 602, so that expansion outer cylinder 4, expansion inner cylinder 5 and inner support body 6 are all changed from folding state to inflation state, under the pressure of contrast medium, expansion inner cylinder 5 and inner support body 6 are inflated to the inside, and expansion outer cylinder 4 is inflated to the outside, but expansion inner cylinder 5 and inner support body 6 traction expansion outer cylinder 4 through all protrusions 601, so that pit is produced in the position of expansion outer cylinder 4 fixedly connected with protrusion 601, so as to inhibit the sliding of expansion outer cylinder 4 relative to pathological position.

[0027] Example 2

[0028] The embodiment provides a function of removing residual air in a balloon catheter to improve the imaging effect on the basis of Embodiment 1.

[0029] Because of the gas in the balloon catheter, the gas in the balloon catheter needs to be first extracted before the contrast agent is injected into the balloon catheter by a pressure pump, which is complex and is not conducive to improving the operation efficiency.

[0030] Referring to Figures 2 to 4 The arc-shaped hole 502 is located at the left part of the expansion inner tube 5, and controls the filling sequence of the contrast agent in the filling cavity 501 and the support cavity 602; the communication member 3, the expansion outer tube 4 and the expansion inner tube 5 are all hydrophilic materials, the hydrophilic property is used to enhance the adhesion effect of the contrast agent and the side wall of the filling cavity 501, and then the gas flow into the contrast agent is inhibited, which is helpful to keep the gas-liquid interface of the contrast agent and the gas in the filling cavity 501 and the support cavity 602 stable.

[0031] In the process of injecting the contrast agent into the filling cavity 501, the contrast agent can ignore the gravity effect under the action of surface tension, and gradually fills the filling cavity 501 from right to left, and the gas existing in the delivery channel and the filling cavity 501 is extruded into the support cavity 602, after the filling cavity 501 is completely filled with the contrast agent, the contrast agent flows into the support cavity 602 through the arc-shaped hole 502, and all the gas is extruded to the end of the support cavity 602, so that the filling ratio of the contrast agent in the filling cavity 501 is kept, and the imaging effect is improved.

[0032] Embodiment 3

[0033] The embodiment improves the expansion effect on the blood vessel on the basis of Embodiment 2.

[0034] In the expansion process of the existing papillary balloon, the papillary structure blocks the blood vessel, causing ischemia of the downstream tissue, therefore, the single expansion time of the balloon is strictly limited in clinical application, so as to avoid tissue damage caused by long-time occlusion, but the short expansion time cannot make the blood vessel wall deform plastically, and the blood vessel is easy to shrink under the elasticity after the balloon is withdrawn, thereby causing the expansion effect on the lesion part to be not ideal.

[0035] Referring to Figures 1 to 4 The communication member 3 is provided with three annularly distributed flow-through holes 301, and the flow-through holes 301 are used for blood flow; all the inner support bodies 6 are staggered with all the flow-through holes 301.

[0036] The above setting can provide a flow channel for blood by using the gaps of all the inner support bodies 6 and the flow-through holes 301, avoid the balloon expansion to block the blood vessel, thereby prolonging the single expansion time and improving the expansion effect on the lesion part.

[0037] Embodiment 4

[0038] The embodiment provides the function of guiding the balloon to contract on the basis of Embodiment 3.

[0039] The balloon catheter currently used is in a circumferentially uniform folded and rolled state when produced, but when the balloon is inflated in the patient's body and then shrunk, the state of the balloon after shrinking cannot be controlled, the balloon can be directly sucked flat but the width is larger than that when inflated, so that the patient's discomfort is increased when the balloon moves in the patient's body.

[0040] Referring to Figure 1 , Figure 2 , Figure 5 and Figure 6 , the left end of the inner tube 2 is fixedly connected with a mounting cylinder 7, the left side of the cross section of the mounting cylinder 7 is a circular arc, so that the probability of scratching the blood vessel by the mounting cylinder 7 is reduced; the right side of the mounting cylinder 7 is fixedly connected with three guide pieces 8 distributed in a ring shape, the guide pieces 8 are fixedly connected with the expansion outer cylinder 4, the guide pieces 8 are made of elastic material, and the guide pieces 8 are used for guiding the expansion outer cylinder 4 to move in the blood vessel; the communication piece 3, the expansion outer cylinder 4 and the three guide pieces 8 form a shuttle shape, so that the balloon catheter is facilitated to move in the patient's body.

[0041] Referring to Figure 1 and Figure 2 , the guide pieces 8 are in a stretched state when the expansion outer cylinder 4 and the expansion inner cylinder 5 are inflated, and the guide pieces 8 are in a free state (the free state herein refers to a state without force) when the expansion outer cylinder 4 and the expansion inner cylinder 5 are contracted; the number of the guide pieces 8 is equal to the number of the through holes 301, and all the through holes 301 and all the guide pieces 8 are distributed alternately.

[0042] The above arrangement can realize that the expansion outer cylinder 4 is pulled by the guide pieces 8, so that the expansion outer cylinder 4 can be close to the surface of the inner tube 2 when being contracted, and then the expansion outer cylinder 4 is uniformly contracted, so that the maximum outer diameter of the balloon catheter in the contracted state is controlled, and the balloon catheter is facilitated to move in the patient's body.

[0043] Embodiment 5

[0044] The embodiment provides the function of inhibiting thrombus formation on the basis of Embodiment 4.

[0045] Referring to Figure 1 , the outer side of the expansion outer cylinder 4, the inner side of the expansion inner cylinder 5 and the outer side of the inner support body 6 are coated with a PTFE coating, the PTFE coating provides good biocompatibility lubricity, reduces the friction with the tissue and blood, reduces the discomfort of the patient, and inhibits the adhesion of platelets, thereby reducing the risk of thrombus formation.

[0046] The above-described embodiments are only used to illustrate the technical solutions of the present application, and are not intended to limit the present application; although the present application has been described in detail with reference to the foregoing embodiments, it should be understood by those skilled in the art that the technical solutions recorded in the foregoing embodiments can still be modified, or some technical features can be replaced by equivalent replacements; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A tissue expansion catheter with a fixed structure, characterized in that: include: An outer tube (1) and an inner tube (2), wherein the inner tube (2) is arranged in the outer tube (1), the end of the outer tube (1) is fixedly connected to a connecting piece (3) fixedly connected to the inner tube (2), the connecting piece (3) is fixedly connected to an expansion outer tube (4) and an expansion inner tube (5), and the three together form a filling chamber (501), the expansion outer tube (4) is fixedly connected to a side of the expansion inner tube (5) away from the connecting piece (3), the expansion inner tube (5) is fixedly connected to an inner support body (6) distributed in an annular manner and in contact with the inner tube (2), the side of the inner support body (6) away from the inner tube (2) passes through the expansion inner tube (5) and is provided with symmetrically distributed The invention relates to a device comprising two groups of protrusions (601), wherein each group of protrusions (601) comprises a plurality of protrusions distributed at equal intervals, wherein the protrusions (601) are fixedly connected to the expansion outer cylinder (4) and are used to pull the expansion outer cylinder (4) when the expansion outer cylinder (4) expands so as to form pits on its surface, wherein the inner support body (6) and the expansion inner cylinder (5) together form a support cavity (602), wherein the expansion inner cylinder (5) is provided with annularly distributed arc holes (502), wherein the number of the arc holes (502) is equal to the number of the inner support body (6), and the support cavity (602) is connected to the filling cavity (501) through adjacent arc holes (502).

2. The tissue expansion catheter with a fixed structure according to claim 1, characterized in that: The arc-shaped hole (502) is located on a side of the expansion inner cylinder (5) away from the connecting piece (3).

3. The tissue expansion catheter with a fixed structure according to claim 2, characterized in that: The connecting piece (3), the expansion outer cylinder (4) and the expansion inner cylinder (5) are all made of hydrophilic materials, which facilitates squeezing the gas in the filling cavity (501) into the supporting cavity (602).

4. The tissue expansion catheter with a fixed structure according to claim 2, characterized in that: The connecting piece (3) is provided with annularly distributed circulation holes (301), and the circulation holes (301) are used for blood circulation.

5. The tissue expansion catheter with a fixed structure according to claim 4, characterized in that: The number of the circulation holes (301) is equal to the number of the inner supporting bodies (6), and all the inner supporting bodies (6) and all the circulation holes (301) are distributed in an alternating manner.

6. The tissue expansion catheter with a fixed structure according to claim 1, characterized in that: The end of the inner tube (2) is fixedly connected to a mounting cylinder (7), and the mounting cylinder (7) is fixedly connected to annularly distributed guide pieces (8). The guide pieces (8) are fixedly connected to the expansion outer cylinder (4), and the guide pieces (8) are used to guide the expansion outer cylinder (4) to move in the blood vessel.

7. The tissue expansion catheter with a fixed structure according to claim 6, characterized in that: The guide piece (8) is made of elastic material. When the expansion outer cylinder (4) and the expansion inner cylinder (5) expand, the guide piece (8) is in a stretched state. When the expansion outer cylinder (4) and the expansion inner cylinder (5) are retracted, the guide piece (8) is in a free state.

8. The tissue expansion catheter with a fixed structure according to claim 6, characterized in that: The number of the guide pieces (8) is equal to the number of the circulation holes (301), and all the circulation holes (301) and all the guide pieces (8) are distributed in an alternating manner.

9. The tissue expansion catheter with a fixing structure according to claim 6, characterized in that: The cross section of the mounting cylinder (7) is in an arc shape on the side away from the expansion outer cylinder (4).

10. The tissue expansion catheter with a fixing structure according to claim 9, characterized in that: The outer side of the expansion outer cylinder (4), the inner side of the expansion inner cylinder (5) and the outer side of the inner support body (6) are all coated with a PTFE coating to inhibit platelet adhesion.

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