Introducer sheath and dilator

Abstract

The present invention provides a catheter sheath and a dilatation tube, wherein the catheter sheath comprises: a mesh tube body, the mesh tube body comprises a plurality of guide rods extending in a direction parallel to the central axis of the mesh tube body and a plurality of connecting rods connecting the guide rods, the adjacent guide rods and connecting rods together form an expandable and contractible parallelogram grid, and the outer diameter of the local mesh tube body where the parallelogram grid is located is adjusted by stretching the parallelogram grid. The present invention can reduce the expansion time of the blood vessel and reduce the risk of postoperative complications through the rapid contraction of the catheter sheath, and promote the catheter sheath to always be in close contact with the blood vessel wall during the operation to prevent bleeding during expansion and contraction.

Description

Technical Field

[0001] The present invention relates to the field of minimally invasive medical devices, in particular to a catheter sheath and a dilation tube. Background Art

[0002] With the widespread application of vascular interventional treatment, various forms of catheter sheaths have also been promoted. In order to reduce postoperative complications, many companies have developed expandable catheter sheaths.

[0003] However, the expandable tube of the existing catheter sheath adopts a rolled wall structure. When the expandable tube of this structure is inserted into a blood vessel, the rolled part is easy to scratch the blood vessel. At the same time, when the expanded tube is retracted, the rolled part is easy to clamp the blood vessel, causing bleeding.

[0004] Therefore, the present invention provides a catheter sheath and dilation tube that will not clamp the blood vessel when retracted. Summary of the invention

[0005] In response to the problems in the prior art, the purpose of the present invention is to provide a catheter sheath and a dilation tube, which overcome the problem of easy clamping of blood vessels after expansion in the prior art, can reduce the expansion time of the blood vessels and reduce the risk of postoperative complications through the rapid contraction of the catheter sheath, and promote the catheter sheath to always be in close contact with the blood vessel wall during the operation to prevent blood leakage during expansion and contraction.

[0006] An embodiment of the present invention provides a catheter sheath, comprising:

[0007] A mesh tube body, the mesh tube body comprising a plurality of guide rods extending in a direction parallel to the central axis of the mesh tube body and a plurality of connecting rods connecting the guide rods, the adjacent guide rods and the connecting rods together form an expandable and contractible parallelogram grid, and the outer diameter of the local mesh tube body where the parallelogram grid is located is adjusted by stretching the parallelogram grid.

[0008] Preferably, the mesh tube body has a distal end and a proximal end, and along the proximal end to the distal end, the area of ​​the parallelogram grids in each part of the mesh tube body decreases and the outer diameter of the mesh tube body decreases.

[0009] Preferably, the mesh tube body includes a first region, a second region, and a third region in sequence from the proximal end to the distal end, the tube diameters of the first region of the mesh tube body are the same, the tube diameters of the third region of the mesh tube body are the same, and the tube diameter of the third region is smaller than the tube diameter of the first region;

[0010] The diameter of the second region of the mesh tube body decreases linearly along the direction from the proximal end to the distal end.

[0011] Preferably, the outer diameter of the local mesh tube body where the parallelogram grid is located is changed by changing the angle of the parallelogram grid.

[0012] Preferably, when the mesh tube body expands, the angle difference between the two angles formed by the two ends of the guide rod in the same parallelogram grid and the two connected connecting rods decreases, and the outer diameter of the mesh tube body in the local area where the parallelogram grid is located increases.

[0013] Preferably, when the mesh tube body contracts, the angle difference between the two angles formed by the two ends of the guide rod in the same parallelogram grid and the two connected connecting rods increases, and the outer diameter of the mesh tube body in the local area where the parallelogram grid is located decreases.

[0014] Preferably, it also includes a first elastic material layer and / or a second elastic material layer, the first elastic material layer wraps the guide rods and connecting rods on the outer surface of the mesh tube body, and the second elastic material layer wraps the guide rods and connecting rods on the inner surface of the mesh tube body.

[0015] Preferably, the distal end of the mesh tube body is a full circle structure composed of multiple arc segments in a non-expanded state.

[0016] An embodiment of the present invention further provides a dilation tube, comprising the catheter sheath as described above.

[0017] Preferably, it also includes:

[0018] a sealing member connected to the proximal end of the catheter sheath;

[0019] an expansion sheath, passing through the sealing member and into the catheter sheath;

[0020] a drain port connected to the seal; and

[0021] A sealing port is connected to the sealing member.

[0022] The catheter sheath and dilation tube of the present invention can reduce the expansion time of the blood vessel and reduce the risk of postoperative complications through the rapid contraction of the catheter sheath, and promote the catheter sheath to always be in close contact with the blood vessel wall during the operation to prevent bleeding during expansion and contraction. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Other features, objectives and advantages of the present invention will become more apparent from a reading of the detailed description of non-limiting embodiments made with reference to the following accompanying drawings.

[0024] Figure 1 It is a schematic structural diagram of the catheter sheath of the present invention.

[0025] Figure 2 for Figure 1 Magnified view of region C.

[0026] Figure 3 It is a schematic diagram of the diamond grid when the mesh tube body of the catheter sheath of the present invention is contracted.

[0027] Figure 4 It is a schematic diagram of the diamond grid when the mesh tube body of the catheter sheath of the present invention is expanded.

[0028] Figure 5 Schematic diagram of the distal end of the catheter sheath of the present invention.

[0029] Figure 6 It is a schematic diagram of manufacturing the mesh tube body of the present invention.

[0030] Figure 7 It is a schematic structural diagram of the expansion tube of the present invention.

[0031] Reference numerals

[0032] 1 Introducing sheath

[0033] 10 Mesh tube

[0034] 11 Guide rod

[0035] 12 Connecting rod

[0036] 13 Full circle structure

[0037] 131 Arc

[0038] 132 Gap

[0039] 14 Diamond Grid

[0040] 15 Cutting Line

[0041] 1A Near End

[0042] 1B Far End

[0043] 2 Drain port

[0044] 3 Sealing port

[0045] 4 Seals

[0046] 5. Dilation Sheath

[0047] p The first angle

[0048] q Second angle DETAILED DESCRIPTION

[0049] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in a variety of forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that the present invention will be comprehensive and complete and fully convey the concepts of the example embodiments to those skilled in the art. The same reference numerals in the figures represent the same or similar structures, and thus their repeated description will be omitted.

[0050] Figure 1 It is a schematic structural diagram of the catheter sheath of the present invention. Figure 2 for Figure 1 Magnified view of region C. Figure 3 It is a schematic diagram of the diamond grid when the mesh tube body of the catheter sheath of the present invention is contracted. Figure 4 FIG. 2 is a schematic diagram of a diamond grid when the mesh tube body of the catheter sheath of the present invention is expanded. Figures 1 to 4 As shown, the catheter sheath of the present invention comprises: a mesh tube body 10. The mesh tube body 10 comprises a plurality of guide rods 11 extending in a direction parallel to the central axis L of the mesh tube body 10, and a plurality of connecting rods 12 connecting the guide rods 11, the guide rods 11 and the connecting rods 12 are integrally formed, and the adjacent guide rods 11 and the connecting rods 12 are enclosed to form an expandable and contractible diamond grid 14, and the outer diameter of the local mesh tube body 10 where the diamond grid 14 is located is adjusted by stretching the diamond grid 14. When the mesh tube body of the catheter sheath expands, the diamond grid 14 has a tendency to deform into a rectangular graphic structure, and when the mesh tube body of the catheter sheath contracts, the diamond grid 14 changes from a nearly rectangular graphic structure back to a diamond. The diamond grids 14 in the present invention are arranged in a matrix, the row direction is the direction of the central axis L of the mesh tube body 10, and the column direction is perpendicular to the row direction. The mesh tube body 10 of the present invention does not have a folded portion, and the rhombus grid 14 of the mesh tube body 10 has a small pattern deformation during elastic deformation, good support effect, fast retraction speed, and is not easy to scratch blood vessels, greatly reducing surgical risks. The grid in the present invention can be any parallelogram, but is not limited thereto.

[0051] When subjected to the internal outward extrusion stress, the diamond grid 14 formed by the guide rod 11 and the connecting rod 12 is deformed and stretched, and the length of the diamond grid 14 in the column direction can be increased (equivalent to increasing the local outer perimeter). Since the diamond grids 14 arranged in a circle along the column direction have increased local outer perimeters, the corresponding local outer perimeter of the mesh tube body 10 increases.

[0052] In a preferred example, the diameter of the guide rod 11 is larger than the diameter of the connecting rod 12, or the rigidity of the guide rod 11 is stronger than the rigidity of the connecting rod 12, so that the connecting rod 12 is easier to twist in accordance with the internal outward extrusion stress, thereby promoting the rapid deformation and stretching of the diamond grid 14, or rapid recovery after the internal outward extrusion stress disappears.

[0053] In a preferred embodiment, the mesh tube body 10 has a distal end 1B and a proximal end 1A. From the proximal end 1A to the distal end 1B, the area of ​​the diamond grids 14 of each part of the mesh tube body 10 decreases and the outer diameter of the mesh tube body 10 decreases, so as to facilitate entry into the blood vessel, but the invention is not limited thereto. The proximal end 1A in the present invention refers to the part close to the sealing member 4 (see Figure 7 ) or the end connected to the seal 4. The distal end 1B in the present invention refers to the end away from the seal 4 (see Figure 7 ) at one end.

[0054] In a preferred example, the mesh tube body 10 includes a first area, a second area, and a third area from the proximal end 1A to the distal end 1B, the diameter of the first area of ​​the mesh tube body 10 is the same, the diameter of the third area of ​​the mesh tube body 10 is the same, and the diameter of the third area is smaller than the diameter of the first area; the diameter of the second area of ​​the mesh tube body 10 decreases linearly from the proximal end 1A to the distal end 1B, so that the mesh tube body 10 as a whole is more convenient to pierce and helps to reduce the wound area. In a preferred example, the outer diameter of the local mesh tube body 10 where the diamond grid 14 is located is changed by changing the angle of the diamond grid 14, but it is not limited to this.

[0055] In a preferred embodiment, when the mesh tube 10 contracts, the angle difference between the two angles formed by the two ends of the guide rod 11 in the same diamond grid 14 and the two connected connecting rods 12 increases, and the outer diameter of the local mesh tube 10 where the diamond grid 14 is located decreases, but the present invention is not limited thereto. Figure 3 When the mesh tube body 10 contracts (normal state), in the same diamond grid 14, the guide rod 11 and the two intersecting connecting rods 12 respectively form a first angle p1 (acute angle) and a second angle q1 (obtuse angle), then the difference between the first angle p1 and the second angle q1 is R1, and the width of the diamond grid 14 along the column direction is W1.

[0056] In a preferred embodiment, when the mesh tube 10 expands, the angle difference between the two angles formed by the two ends of the guide rod 11 in the same diamond grid 14 and the two connected connecting rods 12 is reduced, and the outer diameter of the local mesh tube 10 where the diamond grid 14 is located is increased, but not limited to this. Figure 4 When the mesh tube body 10 is expanded (operation state), in the same diamond grid 14, the guide rod 11 and the two intersecting connecting rods 12 respectively form a first angle p2 (larger acute angle) and a second angle q2 (smaller obtuse angle), then the difference between the first angle p2 and the second angle q2 is R2, and the width of the diamond grid 14 along the column direction is W2. The difference R2 is smaller than the difference R1, and the width W2 is larger than the width W1, so that the circumference of the mesh tube body 10 in the circumferential direction increases.

[0057] In a preferred example, the first elastic material layer wraps the guide rod 11 and the connecting rod 12 on the outer surface of the mesh tube body 10, and the second elastic material layer wraps the guide rod 11 and the connecting rod 12 on the inner surface of the mesh tube body 10, respectively, to avoid scratching the blood vessels, but not limited to this.

[0058] In a preferred embodiment, the mesh tube body 10 is an elastically deformable nickel-titanium tube, which has strong visualization properties. When the catheter sheath 1 passes into a blood vessel, the position of the catheter sheath 1 can be clearly observed, which facilitates the positioning of the catheter sheath 1.

[0059] Figure 5 Schematic diagram of the distal end of the catheter sheath of the present invention. Figure 5 As shown, in a preferred example, the distal end 1B of the mesh tube body 10 is a full-circle structure 13, and the distal end 1B of the mesh tube body 10 is a full-circle structure 13 (closed figure) composed of multiple arc segments in a non-expanded state. The distal end 1B of the mesh tube body 10 is an unclosed annular structure with a larger area formed by multiple arc segments 131 arranged in a circle at intervals in the expanded state, so that the valve can pass through. After the valve passes, the unclosed annular structure will be closed and restored to the full-circle structure 13. When processing the full-circle structure, a laser cutting machine can be used to evenly cut out multiple slits 132 to ensure that the valve can expand smoothly when passing through, so that the phenomenon of scraping the blood vessel during the expansion period and clamping the blood vessel during the contraction period, which is common in the rolled wall expandable tube, will not occur, but it is not limited to this.

[0060] Figure 6 FIG. 2 is a schematic diagram of manufacturing the mesh tube body of the present invention. Figure 6 As shown, a section of nickel-titanium tube is first cut with a laser cutting machine, and a cutting line 15 is set on the nickel-titanium tube to cut and form a diamond grid 14 that covers the nickel-titanium tube, thereby making a catheter sheath 1, and a guide rod 11 and a connecting rod 12 are formed around the diamond grid 14, but the invention is not limited thereto. After heat treatment, sandblasting and polishing, a layer of elastic material is wrapped on the inner and outer surfaces to form a catheter sheath. Figure 1 , 2The catheter sheath 1 shown. The cut nickel-titanium tube is divided into a guide rod 11 and a connecting rod 12. The guide rod 11 is used to fix the overall structure of the catheter sheath 1, prevent radial stretching and compression, and limit the movement direction of the valve in the catheter sheath 1. The connecting rod 12 is used to connect the guide rod 11 to provide circumferential support force. In particular, the connecting rod 12 at the taper position will be relatively dense, providing a larger circumferential support force to prevent the puncture point from being compressed by blood vessels and other tissues, causing wrinkles and bleeding. The catheter sheath 1 is squeezed at the puncture point to reduce its outer diameter. The memory property of nickel-titanium metal can provide a long-lasting chronic outward force, which can make the catheter sheath 1 fit closely with the blood vessel to further prevent bleeding events. In the initial state, the acute angle formed by the connecting rod 12 and the guide rod 11 in the diamond grid 14 is small, and the obtuse angle is large. When the valve enters the catheter sheath 1, since the inner diameter of the catheter sheath 1 is small at this time, the valve will open the catheter sheath 1 outward. At this time, due to the expandability of the nickel-titanium tube, the acute angle formed by the connecting rod 12 and the guide rod 11 in the diamond grid 14 becomes larger, and the obtuse angle becomes smaller, so that the guide rod 11 expands outward, and the diamond grid 14 has a tendency to gradually deform into a rectangular structure, thereby driving the inner and outer diameters of the entire catheter sheath 1 to increase, and the valve can smoothly pass through the catheter sheath 1. After the valve passes through the catheter sheath 1 and enters the human blood vessel, due to the memory of the nickel-titanium tube, the connecting rod 12 will return to its original shape, the acute angle formed by the connecting rod 12 and the guide rod 11 becomes smaller, and the obtuse angle becomes larger, and the diamond grid 14 returns to the diamond state in the non-expanded state, so that the guide rod 11 shrinks inward, thereby driving the inner and outer diameters of the entire catheter sheath 1 to decrease and return to the original size, reducing vascular complications.

[0061] The catheter sheath 1 has a certain taper, with smaller inner and outer diameters at the distal end and larger inner and outer diameters at the proximal end. The maximum inner diameter of the catheter sheath 1 is larger than the outer diameter of the valve, which is convenient for the valve to penetrate. The minimum inner diameter of the catheter sheath 1 is smaller than the outer diameter of the valve, but can expand its inner diameter after being stretched outward by the valve. The minimum outer diameter of the catheter sheath 1 is smaller than the inner diameter of the blood vessel, which is convenient for the catheter sheath 1 to penetrate the human body. The maximum outer diameter of the catheter sheath 1 is larger than the outer diameter of the blood vessel, which is convenient for the catheter sheath 1 to seal the blood vessel puncture point after entering the blood vessel.

[0062] Figure 7 FIG. 2 is a schematic diagram of the structure of the expansion tube of the present invention. Figure 7 As shown, the present invention also provides a dilatation tube, including the catheter sheath 1 as described above, and all technical features of the catheter sheath 1 in the dilatation tube are as described above, and will not be repeated here. In a preferred example, the dilatation tube also includes: a seal 4, a dilatation sheath 5, an emptying port 2 and a sealing port 3. The seal 4 is connected to the proximal end 1A of the catheter sheath 1. The dilatation sheath 5 penetrates into the catheter sheath 1 through the seal 4. The emptying port 2 is connected to the seal 4. The sealing port 3 is connected to the seal 4 to perform the operation.

[0063] The main structure and use method of the expansion tube of the present invention are as follows:

[0064] First use the laser cutting machine to cut a section Figure 1 The nickel-titanium tube shown in the figure is heat-treated, sandblasted and polished, and then coated with a layer of elastic material on the inner and outer surfaces to form a Figure 2 The catheter sheath 1 is shown. The catheter sheath 1 is fixed to the sealing member 4, and the evacuation port 2 and the sealing port 3 are connected, and the expansion sheath 5 is inserted into the catheter sheath 1. When in use, a certain amount of liquid is first injected into the sealing port 3 to make the sealing member 4 sufficiently sealed. Then the expandable sheath is inserted into the blood vessel as a whole, and stops when the inner diameter of the blood vessel is equal to the outer diameter of the expansion tube 1. The expansion sheath 5 is taken out, the evacuation port 2 is opened, and the internal air is exhausted. Finally, the interventional instrument is inserted into the sealing member 4 and the catheter sheath 1, and the operation is started, but this is not limited to this.

[0065] The catheter sheath and dilation tube of the present invention have the following advantages:

[0066] The nickel-titanium tube has a strong developing property. When the catheter sheath 1 passes into the blood vessel, the position of the catheter sheath 1 can be clearly observed, which facilitates the positioning of the catheter sheath 1.

[0067] Due to the visualization property of the nickel-titanium tube, it is also helpful to observe whether the valve is displaced when the valve passes through the catheter sheath 1 and enters the blood vessel.

[0068] Since the nickel-titanium tube is relatively strong, only a very thin nickel-titanium tube is needed to achieve the required expansion effect, so the wall thickness of the self-expanding catheter sheath 1 is significantly smaller than the wall thickness of the rolled-wall catheter sheath.

[0069] Due to the good expansion and contraction properties of the nickel-titanium tube, the catheter sheath 1 always maintains a full-circle structure regardless of expansion or contraction, so that the phenomenon of scraping the blood vessel during expansion and clamping the blood vessel during contraction, which is common in rolled-wall catheter sheaths, will not occur.

[0070] Due to the memory of the nickel-titanium tube, the contact position between the catheter sheath 1 and the blood vessel opening is squeezed by the blood vessel wall, so that the catheter sheath 1 always sticks to the blood vessel wall during the operation, so that the common phenomenon of blood leakage during the expansion and contraction of the expandable tube in the roll-wall catheter sheath will not occur.

[0071] Due to the good expansion and contraction properties of the nickel-titanium tube, when the valve passes through the catheter sheath 1, the catheter sheath 1 can expand quickly, and after the valve passes through the catheter sheath 1, the catheter sheath 1 can contract quickly, thereby reducing the expansion time of the blood vessel and alleviating the risk of postoperative complications.

[0072] The far end of the nickel-titanium tube is a full-circle structure 13, which can ensure that the far end of the catheter sheath 1 has sufficient strength and will not circumferentially wrinkle when entering the blood vessel. At the same time, when processing the full-circle structure, five slits will be evenly cut by a laser cutting machine to ensure that the valve can expand smoothly when passing through.

[0073] In summary, the purpose of the present invention is to provide a catheter sheath and a dilation tube, which can reduce the expansion time of the blood vessel and reduce the risk of postoperative complications through the rapid contraction of the catheter sheath, and promote the catheter sheath to always adhere closely to the blood vessel wall during the operation to prevent bleeding during expansion and contraction.

[0074] The above contents are further detailed descriptions of the present invention in combination with specific preferred embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. For ordinary technicians in the technical field to which the present invention belongs, several simple deductions or substitutions can be made without departing from the concept of the present invention, which should be regarded as falling within the protection scope of the present invention.

Claims

1. A catheter sheath, characterized in that: include: A mesh tube body (10), the mesh tube body (10) comprising a plurality of guide rods (11) extending in a direction parallel to the central axis of the mesh tube body (10) and a plurality of connecting rods (12) connecting the guide rods (11); the adjacent guide rods (11) and the connecting rods (12) together form an expandable and contractible parallelogram grid (14); the outer diameter of the local mesh tube body (10) where the parallelogram grid (14) is located is adjusted by stretching the parallelogram grid (14); the mesh tube body (10) has a distal end (1B) and a proximal end (1A); the distal end (1B) of the mesh tube body (10) is a full circular structure (13) composed of a plurality of circular arcs and having a plurality of gaps (132) in a non-expanded state; the distal end (1B) is an unclosed annular structure with a larger area formed by a plurality of circular arcs (131) arranged in a spaced manner in an expanded state.

2. The catheter sheath according to claim 1, characterized in that Along the proximal end (1A) to the distal end (1B), the area of ​​the parallelogram grid (14) in each part of the mesh tube body (10) decreases and the outer diameter of the mesh tube body (10) decreases.

3. The catheter sheath according to claim 2, characterized in that The mesh tube body (10) includes a first region, a second region, and a third region in sequence from the proximal end (1A) to the distal end (1B), the first region of the mesh tube body (10) having the same tube diameter, the third region of the mesh tube body (10) having the same tube diameter, and the third region having a smaller tube diameter than the first region; The diameter of the second region of the mesh tube body (10) decreases linearly along the direction from the proximal end (1A) to the distal end (1B).

4. The catheter sheath according to claim 1, characterized in that The outer diameter of the local mesh tube body (10) where the parallelogram grid (14) is located is changed by changing the included angle of the parallelogram grid (14).

5. The catheter sheath according to claim 4, characterized in that When the mesh tube body (10) expands, the angle difference between the two angles formed by the two ends of the guide rod (11) in the same parallelogram grid (14) and the two connected connecting rods (12) decreases, and the outer diameter of the mesh tube body (10) in the local area where the parallelogram grid (14) is located increases.

6. The catheter sheath according to claim 4, characterized in that: When the mesh tube body (10) contracts, the angle difference between the two angles formed by the two ends of the guide rod (11) in the same parallelogram grid (14) and the two connected connecting rods (12) increases, and the outer diameter of the mesh tube body (10) in the local area where the parallelogram grid (14) is located decreases.

7. The catheter sheath according to claim 1, characterized in that: It also includes a first elastic material layer and / or a second elastic material layer, wherein the first elastic material layer wraps the guide rod (11) and the connecting rod (12) on the outer surface of the mesh tube body (10), and the second elastic material layer wraps the guide rod (11) and the connecting rod (12) on the inner surface of the mesh tube body (10).

8. An expansion tube, characterized in that: Comprising a catheter sheath (1) as claimed in any one of claims 1 to 7.

9. The expansion tube according to claim 8, characterized in that Also includes: A sealing member (4) connected to the proximal end (1A) of the catheter sheath (1); A dilation sheath (5) is inserted into the catheter sheath (1) through the sealing member (4); an exhaust port (2) connected to the sealing member (4); and The sealing port (3) is connected to the sealing member (4).

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