Micro-catheter assembly and outer diameter controllable balloon thereof

Abstract

The invention discloses a micro catheter assembly and an outer diameter controllable balloon thereof, and relates to the technical field of medical instruments. The balloon with the controllable outer diameter comprises a bearing part and a balloon body, wherein the bearing part is of a tubular structure; the thin film is arranged outside the bearing part; a closed cavity is formed between the thin film and the bearing part; the thin films are laminated to form a plurality of laminated parts; each lamination part at least comprises a first lamination film and a second lamination film; the first laminated film and the second laminated film are any two adjacent films in the corresponding laminated parts; and a plurality of connecting micro columns are arranged between each stacking part and the bearing piece. Through the arrangement of the multiple connecting micro columns, one balloon can achieve two times of pre-expansion of the narrow position with different size requirements, compared with the prior art, operation is easy, the micro catheter does not need to be inserted into the cerebral artery for multiple times, the pre-expansion time of the narrow position can be greatly saved, and the operation difficulty can be reduced.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a microcatheter assembly and a balloon with controllable outer diameter thereof. Background Art

[0002] Cerebral artery occlusion is a serious cerebrovascular disease, which refers to the blockage or occlusion of the intracranial artery, resulting in severe ischemia and hypoxia in the blood supply area of ​​the brain, cerebellum or brainstem. Figure 1 As shown, cerebral artery occlusion is caused by abnormal masses 2 (atheromatous plaques or abnormal hyperplasia masses, etc.) attached to the inner wall of cerebral artery 1. The abnormal mass 2 forms a stenosis 11 inside the cerebral artery 1. The diameter of the stenosis 11 is extremely small or zero, which causes occlusion of the cerebral artery 1, making it difficult for the heart to supply blood to the brain tissue. If things go on like this, the patient will experience symptoms of cerebral infarction such as dizziness, headache, visual impairment, aphasia, limb impairment, and severe cases may fall into a coma, threatening life. In order to solve this technical problem, the prior art generally adopts a method of setting a stent at the stenosis 11 to support the cerebral artery 1, thereby ensuring that the blood in the cerebral artery 1 can pass smoothly through the stenosis 11.

[0003] Specifically, before installing the stent at the stenosis 11, the microcatheter assembly needs to be used to pre-expand the stenosis 11 of the cerebral artery 1 so that the subsequent stent can be smoothly installed at the stenosis 11 of the cerebral artery 1. Figure 2 As shown, the device comprises a micro-guidewire 3, a micro-catheter 4 and a balloon 5, wherein the micro-catheter 4 and the balloon 5 are an integrated structure; the micro-catheter 4 is movably sleeved on the outside of the micro-guidewire 3. When in use, the micro-guidewire 3 is first passed through the narrow part 11 of the cerebral artery 1; then the micro-catheter 4 is passed through the narrow part 11 of the cerebral artery 1 along the micro-guidewire 3 until the balloon 5 is located at the narrow part 11 of the cerebral artery 1; finally, a medium (air or saline solution, etc.) is filled into the balloon 5 through the micro-catheter 4 so that the balloon 5 can be inflated, and then the balloon 5 is inflated. Figure 3 The inflated balloon 5 shown can pre-dilate the stenosis 11 of the cerebral artery 1 .

[0004] It should be noted that in the application scenario of cerebral artery occlusion, that is, Figure 1As shown, the size of the abnormal mass 2 in the cerebral artery 1 is relatively large, while the size of the stenosis 11 is relatively small. If the size of the stenosis 11 is expanded to the desired size at one time using the balloon 5, the cerebral artery 1 is likely to rupture, thereby causing a medical accident. In order to avoid the occurrence of such a medical accident, if the size of the stenosis 11 is relatively small, it is generally necessary to use a balloon 5 with a smaller size after expansion (hereinafter referred to as the first balloon) to pre-expand the stenosis 11 for the first time, and then use a balloon 5 with a larger size after expansion (hereinafter referred to as the second balloon) to pre-expand the stenosis 11 for the second time. In the prior art, the operation steps of pre-dilation of the stenosis 11 twice are as follows: first, through the guidance of the micro-guidewire 3, the micro-catheter 4 carrying the first balloon is passed through the stenosis 11, and the first balloon is moved to the stenosis 11, and the first balloon is inflated, so that the first balloon can pre-dilate the stenosis 11 for the first time; then, the micro-catheter 4 carrying the first balloon is extracted from the cerebral artery 1; finally, through the guidance of the micro-guidewire 3, the micro-catheter 4 carrying the second balloon is passed through the stenosis 11, and the second balloon is moved to the stenosis 11, and the second balloon is inflated, so that the second balloon can pre-dilate the stenosis 11 for the second time. The above-mentioned operation steps of pre-dilation of the stenosis 11 twice are relatively cumbersome, resulting in a long operation time and high operation difficulty. It is easy to understand that the longer the operation time, the greater the risk borne by the patient, and the operation of repeatedly extracting and inserting the micro-catheter 4 increases the risk of damage to the inner wall of the cerebral artery 1 accordingly. Summary of the invention

[0005] The purpose of the present application is to provide a microcatheter assembly and a balloon with controllable outer diameter thereof, so as to solve the technical problems in the prior art that the two pre-dilatation operations of the cerebral artery are time-consuming and difficult to operate.

[0006] To achieve the above objectives, this application provides the following technical solutions:

[0007] In the first aspect, the present application proposes a technical solution for a balloon with a controllable outer diameter, which is applied to a microcatheter, and the balloon with a controllable outer diameter comprises:

[0008] A bearing member, wherein the bearing member is a tubular structure;

[0009] A film is arranged on the outside of the carrier; a closed cavity is formed between the film and the carrier; the film is stacked to form a plurality of stacked parts; each stacked part includes at least a first stacked film and a second stacked film; the first stacked film and the second stacked film are any two adjacent films in the corresponding stacked part; a plurality of connecting microcolumns are arranged between each stacked part and the carrier, and each connecting microcolumn is distributed in an axial array along the carrier; the fracture stress of the connecting microcolumns is less than the cracking stress of the film; one end of each connecting microcolumn is connected to the first stacked film, and the other end of each connecting microcolumn is connected to the second stacked film; or, one end of each connecting microcolumn is connected to the film, and the other end of each connecting microcolumn is connected to the carrier.

[0010] As a specific technical solution in the present application, the supporting member can be movably mounted on the outside of the microcatheter; the outer diameter controllable balloon also includes a push catheter; the push catheter is connected to the rear end of the supporting member, and the push catheter is communicated with the closed cavity.

[0011] As a specific technical solution in the present application, the support member includes a support tube; guide parts are provided at both ends of the support tube; the outer diameter of the guide part decreases along the first direction; the first direction is parallel to the axial direction of the support tube, and is pointed from the guide part to the support tube.

[0012] As a specific technical solution in the present application, the maximum outer diameter of the guide portion is greater than the outer diameter of the supporting tube; and the film is arranged between the two guide portions.

[0013] As a specific technical solution in the present application, a placement groove is formed between the supporting tube and the two guide parts; the film is arranged in the placement groove.

[0014] As a specific technical solution in the present application, a plurality of micro-titanium alloy wires are arranged inside the film; each micro-titanium alloy wire is used to form elastic potential energy if the current state of the film is different from the initial state, and the elastic potential energy is used to make the film tend to change from the current state to the initial state.

[0015] As a specific technical solution in the present application, each micro-titanium alloy wire is in the shape of a ring connected end to end, and the folding shape of each micro-titanium alloy wire is the same as the stacking shape of the film; or, the micro-titanium alloy wire is arranged at the stacking turning point of the film, and the micro-titanium alloy wire makes the stacked film of two adjacent layers tend to close together.

[0016] In a second aspect, the present application proposes a microcatheter assembly, which includes a balloon with controllable outer diameter as described in any one of the first aspects.

[0017] As a specific technical solution in this application, the microcatheter assembly includes:

[0018] Micro guide wire;

[0019] The balloon with controllable outer diameter as described in any one of the first aspects;

[0020] Microcatheter; the outer diameter of the microcatheter is smaller than the inner diameter of the carrier.

[0021] As a specific technical solution in the present application, the microcatheter is further provided with a limiting ring, which is close to the front end of the microcatheter; the maximum outer diameter of the limiting ring is greater than the inner diameter of the supporting member.

[0022] Compared with the prior art, the beneficial effects of this application are:

[0023] The present application uses a plurality of connected microcolumns to enable one balloon to achieve two pre-dilations of different sizes for the stenosis. Compared with the prior art, the operation is simple, and there is no need to insert a microcatheter into the cerebral artery multiple times. The application can also greatly save the time for pre-dilation of the stenosis, reduce the difficulty of operation, and thus reduce the risk to the patient during the operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Schematic diagram of cerebral artery occlusion;

[0025] Figure 2 It is a three-dimensional schematic diagram of a micro-catheter assembly in the prior art;

[0026] Figure 3 To adopt Figure 2 Schematic diagram of the microcatheter assembly in the pre-dilation of the stenosis of the cerebral artery;

[0027] Figure 4 A three-dimensional schematic diagram of a microcatheter assembly proposed in an embodiment of the present application;

[0028] Figure 5 for Figure 4 Schematic diagram of the front view of the microcatheter assembly;

[0029] Figure 6 A cross-sectional schematic diagram of a balloon with controllable outer diameter proposed in an embodiment of the present application;

[0030] Figure 7 A cross-sectional schematic diagram of another outer diameter controllable balloon proposed in an embodiment of the present application;

[0031] Figure 8 A three-dimensional schematic diagram of a carrier proposed in an embodiment of the present application;

[0032] Fig. 9A balloon with controllable outer diameter is provided in the embodiment of the present application according to Figure 5 Schematic cross-sectional view of the AA line;

[0033] Fig.10 for Fig. 9 An enlarged view of part B;

[0034] Fig.11 for Fig. 9 After the first inflation of the medium-outer diameter controllable balloon, Figure 5 Schematic cross-sectional view of the AA line;

[0035] Fig.12 for Fig. 9 After the second inflation of the medium-outer diameter controllable balloon, Figure 5 Schematic cross-sectional view of the AA line;

[0036] Fig.13 Another outer diameter controllable balloon proposed in the embodiment of the present application is as follows Figure 5 Schematic cross-sectional view of the AA line;

[0037] Fig.14 Another outer diameter controllable balloon proposed in the embodiment of the present application is according to Figure 5 Schematic cross-sectional view of the AA line;

[0038] Fig.15 for Fig. 9 Another enlarged view of part B;

[0039] Fig.16 for Fig. 9 After the movable balloon is inflated for the first time, Figure 5 Schematic diagram of the cross-section along line AA.

[0040] In the figure: 1. cerebral artery; 11. stenosis; 2. abnormal mass; 3. micro guide wire; 4. micro catheter; 41. limiting ring; 5. balloon; 51. closed cavity; 52. supporting member; 521. supporting tube; 522. guide part; 523. placement groove; 53. film; 531. connecting micro pillar; 532. micro titanium alloy wire; 533. first laminated membrane; 534. second laminated membrane; 6. push catheter. DETAILED DESCRIPTION

[0041] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0042] It should be noted that, in the description of the present application, the terms "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present application.

[0043] Furthermore, it should be understood that for the sake of ease of description, the sizes of the various components shown in the drawings are not drawn according to actual proportions. For example, the thickness or width of certain layers may be exaggerated relative to other layers.

[0044] It should be noted that like reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined or described in one drawing, it will not require further detailed discussion and description in the description of the subsequent drawings.

[0045] Before understanding the embodiments of the present application, it should be clear that in the embodiments of the present application below, only the application scenario of cerebral artery occlusion is used as an example to illustrate the microcatheter assembly and the outer diameter controllable balloon thereof proposed in the present application. It does not mean that the microcatheter assembly and the outer diameter controllable balloon thereof proposed in the present application are only applicable to the application scenario of cerebral artery occlusion. It should be understood that the microcatheter assembly and the outer diameter controllable balloon thereof proposed in the present application are applicable to all other application scenarios similar to the application scenario of cerebral artery occlusion. For example, application scenarios such as coronary artery occlusion or pulmonary artery occlusion are not listed one by one here.

[0046] It should be noted that, in this embodiment, Figure 1 As shown, if the application scenario is cerebral artery occlusion, the minimum diameter of the stenosis 11 is zero; if the application scenario is cerebral artery stenosis, the minimum diameter of the stenosis 11 is greater than zero. That is to say, in this embodiment, there is no restriction on the application scenario of the microcatheter assembly and the balloon with controllable outer diameter, which can be cerebral artery stenosis or cerebral artery occlusion.

[0047] Before understanding the embodiments of the present application, it is also necessary to understand that most of the parts in the microcatheter assembly (for example, micro-guidewire 3, microcatheter 4 or balloon 5, etc.) have two ends. In the embodiments of the present application below, the two ends of a part are defined as the front end and the rear end, respectively, where the front end refers to the end of the part that first enters the cerebral artery 1 when in use, and the rear end refers to the end of the part that does not enter or enters the cerebral artery 1 later when in use, which will not be described in detail later.

[0048] In order to solve the technical problems of the prior art that the two-time pre-dilatation of the cerebral artery takes a long time and is difficult to operate, the present application proposes a balloon with a controllable outer diameter, which is applied to a microcatheter 4. Specifically, the balloon with a controllable outer diameter includes a carrier 52 and a film 53. The carrier 52 is a hollow tubular structure, and the film 53 is arranged outside the carrier 52, and a closed cavity 51 is formed between the film 53 and the carrier 52. Fig. 9 As shown, the film 53 is stacked to form a plurality of stacked portions. Fig.10 As shown, each stacking part includes at least a first stacking film 533 and a second stacking film 534; the first stacking film 533 and the second stacking film 534 are any two adjacent films in the corresponding stacking part; a plurality of connecting micro-pillars 531 are formed between the first stacking film 533 and the second stacking film 534, and each connecting micro-pillar 531 is distributed in an axial array along the supporting member 52; one end of each connecting micro-pillar 531 is connected to the first stacking film 533, and the other end of each connecting micro-pillar 531 is connected to the second stacking film 534; the fracture stress of the connecting micro-pillar 531 is less than the cracking stress of the film 53.

[0049] When in use, the microcatheter 4 can be guided through the narrow part 11 by the micro-guidewire 3; then, the balloon 5 (hereinafter referred to as the outer diameter controllable balloon) carrying the film 53 can be moved to the narrow part 11 through the push catheter 6 under the guidance of the microcatheter 4; further, a medium with a pressure less than the fracture stress of the connected micro-pillar 531 is injected into the closed cavity 51 through the push catheter 6, and then Fig. 9 The film 53 shown can be expanded, and the expanded film 53 is as shown in FIG. Fig.11 As shown, the first pre-expansion can be performed on the stenosis 11. After the first pre-expansion is completed, a medium with a pressure greater than the fracture stress of the connecting micro-pillar 531 and a pressure less than the cracking stress of the film 53 is injected into the closed cavity 51 through the push catheter 6, so that the film 53 can be further expanded. Fig.12 As shown, the stenosis 11 can be pre-dilated for the second time. That is to say, in this embodiment, the pre-dilation of the stenosis 11 twice with different size requirements can be achieved by using one balloon 5. Compared with the prior art, the operation is simple, and there is no need to insert the microcatheter 4 into the cerebral artery multiple times. It can also greatly save the time of pre-dilation of the stenosis 11, reduce the difficulty of operation, and also reduce the risk borne by the patient during the operation.

[0050] In another embodiment of the present application, Fig.15 As shown, one end of each connecting micro-pillar 531 can be connected to the film 53; the other end of each connecting micro-pillar 531 can be connected to the support 52 (that is, the support tube 521). When in use, a medium with a pressure less than the fracture stress of the connecting micro-pillar 531 is injected into the closed cavity 51 through the push conduit 6. Fig. 9The film 53 shown can be expanded, and the expanded film 53 is as shown in FIG. Fig.16 As shown, the first pre-expansion can be performed on the stenosis 11. After the first pre-expansion is completed, a medium with a pressure greater than the fracture stress of the connecting micro-pillar 531 and a pressure less than the cracking stress of the film 53 is injected into the closed cavity 51 through the push catheter 6, so that the film 53 can be further expanded. Fig.12 As shown, the stenosis 11 can be pre-dilated a second time.

[0051] In the embodiment of the present application, there is no restriction on the shape and structure of the carrier 52. For example, the carrier 52 can be the micro-catheter 4 itself. In other words, the film 53 can be directly disposed on the micro-catheter 4, that is, the film 53 and the micro-catheter 4 are an integrated structure. Figure 2 As shown, the microcatheter 4 and the balloon 5 of the prior art are also an integrated structure, and the balloon 5 is at a certain distance from the front end of the microcatheter 4. If the stenosis 11 is located at the end of the cerebral artery 1, when in use, although the front end of the microcatheter 4 can smoothly pass through the stenosis 11, the balloon 5 on the microcatheter 4 is difficult to smoothly reach the stenosis 11. If the balloon 5 is forcibly pushed to the stenosis 11, since the end of the cerebral artery 1 (that is, various capillaries) has limited accommodation space, the front end of the microcatheter 4 may damage the inner wall of the end of the cerebral artery 1 at the least, or cause the cerebral artery 1 to rupture at the most serious.

[0052] In order to solve the technical problem that the microcatheter assembly of the prior art is difficult to be applied to the stenosis of the terminal of the cerebral artery, in one embodiment of the present application, the carrier 52 may not be the microcatheter 4 itself, and the carrier 52 can be movably sleeved on the outside of the microcatheter 4. The outer diameter controllable balloon also includes a push catheter 6; the push catheter 6 is connected to the rear end of the carrier 52, and the push catheter 6 is connected to the closed cavity 51.

[0053] When in use, firstly, the microguidewire 3 is passed through the stenosis 11 of the cerebral artery 1; then, under the guidance of the microguidewire 3, the microcatheter 4 is passed through the stenosis 11 of the cerebral artery 1; further, under the guidance of the microcatheter 4, the outer diameter controllable balloon is moved to the stenosis 11 of the cerebral artery 1 through the push catheter 6; finally, the closed cavity 51 in the outer diameter controllable balloon is filled with a medium (for example, air or saline) through the push catheter 6 to inflate the outer diameter controllable balloon, thereby pre-dilatating the stenosis 11 of the cerebral artery 1.

[0054] It should be noted that in the application scenario of cerebral artery occlusion, the microcatheter 4 is also used to inject contrast agent into the cerebral artery 1 to confirm whether the microcatheter 4 passes through the stenosis 11 (that is, the abnormal block 2). It is easy to understand that if the microcatheter 4 does not pass through the abnormal block 2, it means that the front end of the microcatheter 4 is blocked by the abnormal block 2, that is, the microcatheter 4 cannot normally spray contrast agent, that is, normal angiography cannot be performed; if the microcatheter 4 passes through the abnormal block 2, it means that the front end of the microcatheter 4 is not blocked by the abnormal block 2, that is, the microcatheter 4 can spray contrast agent, that is, normal angiography can be performed. Spraying contrast agent through the microcatheter 4 to confirm whether the front end of the microcatheter 4 passes through the abnormal block 2 (that is, the stenosis 11) is a mature technology and will not be described here.

[0055] In this embodiment, since the outer diameter controllable balloon can be moved along the microcatheter 4 through the push catheter 6, as long as the microcatheter 4 can smoothly pass through the stenosis 11 of the cerebral artery 1, the outer diameter controllable balloon can also smoothly pass through the stenosis 11 of the cerebral artery 1, and then the stenosis 11 can be pre-dilated based on the outer diameter controllable balloon. Compared with the prior art, the embodiment of the movable balloon proposed in this application can be applicable to the application scenario where the stenosis is located at the end of the cerebral artery.

[0056] In the embodiment of the present application, the push catheter 6 is a catheter that can apply a push force to the outer diameter controllable balloon, so the push catheter 6 needs to have a certain rigidity. If the rigidity of the push catheter 6 is too strong, the push catheter 6 is likely to cause damage to the vascular wall of the cerebral artery 1 during the pushing process. In order to ensure that the push catheter 6 has a certain rigidity and is not easy to cause damage to the vascular wall of the cerebral artery 1, in the embodiment of the present application, the material of the push catheter 6 can be the same as that of the microcatheter 4. For example, the push catheter 6 can be made of polyamide, polyurethane, or polytetrafluoroethylene.

[0057] In the embodiment, there is no limitation on the shape and structure of the outer diameter controllable balloon, as long as the outer diameter controllable balloon can move along the microcatheter 4 under the push and pull action of the push catheter 6 and can expand after being filled with a medium. For example, the outer diameter controllable balloon can be at least as shown in the following two embodiments.

[0058] Example 1 of a balloon with controllable outer diameter

[0059] In this embodiment, the outer diameter controllable balloon (i.e., balloon 5) can be as follows: Figure 6 As shown, it can be an integrally formed balloon with uniform wall thickness, that is, the wall thickness of the carrier 52 and the film 53 is the same. As can be seen from the foregoing, the outer diameter controllable balloon needs to be able to move along the microcatheter 4 under the pushing action of the push catheter 6, that is, the outer diameter controllable balloon itself needs to have good rigidity. After reaching the stenosis 11, the outer diameter controllable balloon needs to be inflated, that is, the outer diameter controllable balloon itself also needs to have good flexibility.

[0060] Example 2 of the balloon with controllable outer diameter

[0061] If the balloon 5 is integrally formed and has a uniform wall thickness, the balloon 5 is either insufficiently rigid or insufficiently flexible, that is, the use effect of the balloon 5 is poor. Figure 7 As shown, the wall thickness of the support member 52 is significantly greater than the wall thickness of the film 53. When in use, the support member 52 is mainly used to provide rigidity so that the outer diameter controllable balloon can move along the microcatheter 4 under the pushing action of the push catheter 6. The film 53 is mainly used to provide flexibility so that after the outer diameter controllable balloon reaches the stenosis 11, the medium is filled into the closed cavity 51, and the film 53 can swell, thereby pre-dilatating the stenosis 11. In this embodiment, the balloon 5 has a good use effect by setting the support members 52 and the film 53 with different wall thicknesses. It should be noted that, in this embodiment, the strong rigidity of the support member 52 means that the rigidity of the support member 52 is greater than the rigidity of the film 53. Since the support member 52 needs to pass through the blood vessel when in use, the support member 52 also needs to be able to bend appropriately to adapt to the bending changes of the blood vessel.

[0062] In this embodiment, the material of the support member 52 can be the same as that of the film 53. If the material of the support member 52 and the film 53 is the same, the thickness of the support member 52 along the radial direction of the balloon 5 should be significantly greater than the thickness of the film 53, so that the support member 52 has good rigidity and the film 53 can have good flexibility.

[0063] In the embodiment of the present application, there is no limitation on the shape and structure of the support member 52. For example, the support member 52 may be in the shape of a round tube (for example, only including Figure 8 The support tube 521 shown in FIG. 5 , or the support member 52 may be as shown in FIG. Figure 8 As shown, it includes a support tube 521. Both ends of the support tube 521 are provided with guide parts 522, and the outer diameter of the guide parts 522 decreases along the first direction. The first direction is parallel to the axial direction of the support tube 521, and the guide parts 522 point to the support tube 521.

[0064] It should be clear that, since the outer diameter of each guide portion 522 decreases along the first direction, the first direction is parallel to the axial direction of the support tube 521, and the first direction is directed from the guide portion 522 to the support tube 521. In other words, during the movement of the support member 52 in the cerebral artery 1, since the outer diameters of the front and rear ends of the support member 52 are both small and decrease, the support member 52 is easy to move in the cerebral artery 1, and the front or rear end of the support member 52 is not easy to damage the inner wall of the cerebral artery 1.

[0065] It is easy to understand that in this embodiment, the expansion and contraction of the balloon 5 mainly depends on the film 53. After the film 53 changes from the expanded state to the contracted state, wrinkles or protrusions are easily formed on its surface. If these wrinkles or protrusions form friction with the inner wall of the cerebral artery 1, it is easy to damage the inner wall of the cerebral artery 1. In order to prevent the film 53 from forming friction with the inner wall of the cerebral artery 1 during the movement of the balloon with controllable outer diameter, that is, the film 53 is not easy to damage the inner wall of the cerebral artery 1, in this embodiment, Figure 8 As shown, the maximum outer diameter of the guide portion 522 can be greater than the outer diameter of the support tube 521, that is, a placement groove 523 can be formed between the support tube 521 and the two guide portions 522. When in use, the film 53 can be arranged between the two guide portions 522, that is, the film 53 is arranged in the placement groove 523. Since the film 53 is located in the placement groove 523, the film 53 will not form friction with the inner wall of the cerebral artery 1 during the movement of the outer diameter controllable balloon. If the film 53 does not form friction with the inner wall of the cerebral artery 1, the film 53 will not easily damage the inner wall of the cerebral artery 1.

[0066] In the embodiments of the present application, Figure 7 As shown, the film 53 may be a film with excellent elasticity, so when the medium is filled into the closed cavity 51, the film 53 can swell, thereby pre-dilatating the stenosis 11. Fig. 9 As shown, the film 53 can also be a film with poor elasticity. During production, the film 53 can be stacked and arranged in the placement groove 523. When the medium is filled into the closed cavity 51, the film 53 can also swell, thereby pre-dilatating the stenosis 11. At this point, the second embodiment of the outer diameter controllable balloon is introduced.

[0067] It should be noted that if the film 53 has excellent elasticity, after the medium in the closed cavity 51 is extracted, the film 53 can automatically retract into the placement groove 523 under the action of its own elasticity. That is, after the pre-expansion is completed, the film 53 with excellent elasticity can still maintain a state where it does not form friction with the inner wall of the cerebral artery 1, that is, the film 53 with excellent elasticity is not easy to damage the inner wall of the cerebral artery 1. If the film 53 has poor elasticity and is arranged in the placement groove 523 in a stacked manner, after use, even if the medium in the closed cavity 51 is extracted, it cannot be guaranteed that the film 53 can be completely retracted into the placement groove 523. If the film 53 has wrinkles or protrusions, these wrinkles or protrusions may protrude outside the placement groove 523, and then form friction with the inner wall of the cerebral artery 1, that is, the inner wall of the cerebral artery 1 may be damaged.

[0068] In order to ensure that the film 53 can be completely and smoothly retracted into the placement groove 523 after the medium in the closed chamber 51 is extracted regardless of the elasticity of the film 53. Fig.13As shown, a plurality of titanium alloy microwires 532 (i.e., Fig.13 Or Fig.14 Each titanium alloy wire 532 is used to determine the current state of the film 53 (e.g., Fig.11 and Fig.12 The used state shown) and the initial state (that is, Fig.13 If the state of use is different from that shown in the figure, each micro-titanium alloy wire 532 forms elastic potential energy, and the elastic potential energy is used to make the film 53 have a tendency to change from the current state to the initial state.

[0069] In this embodiment, the Fig.13 As shown in FIG. 1 , each micro titanium alloy wire 532 is in a ring shape connected end to end, and the folded shape of the micro titanium alloy wire 532 is the same as the stacked shape of the film 53. That is, if the film 53 is supported by an external force, when the external force is removed, the film 53 can be restored to its initial state under the elastic force formed by the micro titanium alloy wire 532, that is, restored to the state as shown in FIG. Fig.13 In this embodiment, the initial stacking form can also be Fig.14 As shown in FIG. 1 , a micro titanium alloy wire 532 is arranged at the stacking turning point of the film 53, and the micro titanium alloy wire 532 makes the stacked films of two adjacent layers have a tendency to close together. That is to say, if the film 53 is supported by an external force, when the external force is removed, the two layers of film at the stacking turning point of the film 53 close together under the elastic force of the micro titanium alloy wire 532, and finally can be restored to the initial state, that is, restored to the state as shown in FIG. Fig.14 The initial stacking morphology is shown.

[0070] It should be noted that in the embodiments of the present application, only Fig.13 and Fig.14 The stacking state of the film 53 shown in the figure is used to illustrate the initial state of the film 53 of the present application, and does not mean that the film 53 in the embodiment of the present application can only be stacked as shown in the figure. Fig.13 or Fig.14 It should be understood that in the embodiment of the present application, the film 53 can be stacked according to actual needs, that is, different types of balloons 5 can have films 53 in different stacking states.

[0071] The embodiment of the outer diameter controllable balloon proposed in the present application, through the arrangement of multiple connected micro-columns, enables one balloon to achieve two pre-dilations of different size requirements for the stenosis. Compared with the prior art, it is simple to operate and does not require the insertion of microcatheters into the cerebral arteries multiple times. It can also greatly save the time for pre-dilation of the stenosis and reduce the difficulty of operation, that is, reduce the risks borne by the patient during the operation.

[0072] After introducing the outer diameter controllable balloon proposed in the embodiment of the present application, a microcatheter assembly proposed in the embodiment of the present application is introduced below. Specifically, the microcatheter assembly includes the outer diameter controllable balloon proposed in any one of the above embodiments.

[0073] It should be clear that since the microcatheter assembly includes a balloon with controllable outer diameter as proposed in any of the above embodiments, the balloon in the microcatheter assembly is provided with multiple connected microcolumns, so that one balloon can achieve two pre-dilations of different sizes for the stenosis. Compared with the prior art, it is simple to operate, does not require the microcatheter to be inserted into the cerebral artery multiple times, and can greatly save the time for pre-dilation of the stenosis, reduce the difficulty of operation, and thus reduce the risks borne by the patient during the operation.

[0074] It should be noted that if Figure 3 As shown, when the microcatheter assembly in the prior art is dilating the stenosis 11 of the cerebral artery 1, the balloon 5 will block the entire cerebral artery 1. If the operation time is long, the patient's brain or head and other organs will be insufficiently supplied with blood. In severe cases, it will cause irreversible damage to the patient. In order to avoid the outer diameter controllable balloon blocking the entire cerebral artery 1 when dilating the stenosis 11, in one embodiment of the present application, the microcatheter assembly also includes a micro guidewire 3 and a microcatheter 4. Fig. 9 As shown, the outer diameter of the microcatheter 4 (i.e. Fig. 9 The outer diameter d) shown is smaller than the inner diameter (ie, the inner diameter of the support member 52 (ie, the support tube 521) Fig. 9 As shown in the foregoing, since the support member 52 has a certain rigidity, when the medium is filled into the closed cavity 51, the inner wall of the support member 52 will not completely fit with the outer wall of the microcatheter 4. If the inner wall of the support member 52 and the outer wall of the microcatheter 4 are not completely fitted, the blood in the cerebral artery 1 can flow freely through the gap between the support member 52 and the microcatheter 4. That is, it can effectively avoid the phenomenon of insufficient blood supply to the patient's brain or head organs due to complete blockage of the cerebral artery 1 when the stenosis 11 of the cerebral artery 1 is expanded.

[0075] As can be seen from the foregoing, the microcatheter assembly proposed in the present application can be applied to the application scenario where the stenosis 11 is located at the end of the cerebral artery 1. Since the accommodation space at the end of the cerebral artery 1 is limited, if the stenosis 11 is located at the end of the cerebral artery 1, the front end of the microcatheter 4 must be close to the stenosis 11 during use. If the front end of the microcatheter 4 is close to the stenosis 11, there is a risk that the outer diameter-controlled balloon will be separated from the microcatheter 4 when the outer diameter-controlled balloon is moved by the push catheter 6. As can be seen from the foregoing, the microcatheter 4 is mainly used to guide the movement of the outer diameter-controlled balloon. If the outer diameter-controlled balloon is separated from the microcatheter 4, it is difficult to remove the outer diameter-controlled balloon from the cerebral artery 1 without damaging the cerebral artery 1. In order to avoid the outer diameter-controlled balloon from being separated from the microcatheter 4 during use, in one embodiment of the present application, the microcatheter 4 may also be provided with a limiting ring 41, such as Figure 4 and Figure 5 As shown, the limiting ring 41 is close to the front end of the microcatheter 4, and the maximum outer diameter of the limiting ring 41 is larger than the inner diameter of the outer diameter controllable balloon (that is, as shown in FIG. Fig. 9 Inner diameter D) shown.

[0076] It should be noted that, in this embodiment, since the outer diameter of the limiting ring 41 is larger than the inner diameter of the outer diameter controllable balloon, the outer diameter controllable balloon cannot be separated from the microcatheter 4 by the front end of the microcatheter 4 under the limiting effect of the limiting ring 41. In this embodiment, the distance between the front end face of the limiting ring 41 and the front end face of the microcatheter 4 (i.e., the distance between the front end face of the limiting ring 41 and the front end face of the microcatheter 4) is Figure 5 Of course, in other embodiments of the present application, the distance between the front end face of the limiting ring 41 and the front end face of the micro-catheter 4 can also be greater than 2 mm, for example, 4 mm or 5 mm, etc., which is not limited here.

[0077] In the embodiment of the present application, the limiting ring 41 can be any ring shape that can limit the movement of the outer diameter controllable balloon. For example, the limiting ring 41 can be a ring shape with a square longitudinal section, wherein the longitudinal section is a section parallel to the axis of the limiting ring 41; the limiting ring 41 can also be Figure 4 and Figure 5 It is easy to understand that if the longitudinal section of the limiting ring 41 is a semicircle, the limiting ring 41 is not easy to damage the inner wall of the cerebral artery 1 when moving in the cerebral artery 1.

[0078] Although the embodiments of the present application have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present application, and that the scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A balloon with controllable outer diameter, applied to a microcatheter (4), characterized in that: The outer diameter controllable balloon comprises: A carrier (52), wherein the carrier (52) is a tubular structure; A film (53) is arranged outside the carrier (52); a closed cavity (51) is formed between the film (53) and the carrier (52); the film (53) is stacked to form a plurality of stacked sections; each stacked section at least includes a first stacked film (533) and a second stacked film (534); the first stacked film (533) and the second stacked film (534) are any two adjacent films in the corresponding stacked section; a plurality of connecting microcolumns (531) are arranged between each stacked section and the carrier (52), each The connecting microcolumns (531) are distributed in an axial array along the supporting member (52); the fracture stress of the connecting microcolumns (531) is less than the cracking stress of the film (53); one end of each connecting microcolumn (531) is connected to the first stacked film (533), and the other end of each connecting microcolumn (531) is connected to the second stacked film (534); or, one end of each connecting microcolumn (531) is connected to the film (53), and the other end of each connecting microcolumn (531) is connected to the supporting member (52).

2. The outer diameter controllable balloon according to claim 1, characterized in that: The supporting member (52) can be movably sleeved on the outside of the microcatheter (4); the outer diameter controllable balloon also includes a push catheter (6); the push catheter (6) is connected to the rear end of the supporting member (52), and the push catheter (6) is communicated with the closed cavity (51).

3. The outer diameter controllable balloon according to claim 2, characterized in that: The supporting member (52) comprises a supporting tube (521); both ends of the supporting tube (521) are provided with guide portions (522); the outer diameter of the guiding portion (522) decreases along a first direction; the first direction is parallel to the axial direction of the supporting tube (521), and is directed from the guiding portion (522) to the supporting tube (521).

4. The outer diameter controllable balloon according to claim 3, characterized in that: The maximum outer diameter of the guide portion (522) is greater than the outer diameter of the supporting tube (521); and the film (53) is arranged between the two guide portions (522).

5. The outer diameter controllable balloon according to claim 4, characterized in that: A placement groove (523) is formed between the supporting tube (521) and the two guide parts (522); the film (53) is arranged in the placement groove (523).

6. The balloon with controllable outer diameter according to any one of claims 1 to 5, characterized in that: A plurality of micro titanium alloy wires (532) are arranged inside the film (53); each micro titanium alloy wire (532) is used to form elastic potential energy if the current state of the film (53) is different from the initial state, and the elastic potential energy is used to make the film (53) tend to change from the current state to the initial state.

7. The outer diameter controllable balloon according to claim 4, characterized in that: Each micro-titanium alloy wire (532) is in the shape of a ring connected end to end, and the folding shape of each micro-titanium alloy wire (532) is the same as the stacking shape of the film (53); or, the micro-titanium alloy wire (532) is arranged at the stacking turning point of the film (53), and the micro-titanium alloy wire (532) makes the stacked films of two adjacent layers tend to close together.

8. A microcatheter assembly, characterized in that: Comprising the balloon with controllable outer diameter as described in any one of claims 1 to 7.

9. The microcatheter assembly according to claim 8, characterized in that: The microcatheter assembly comprises: Micro guide wire (3); The balloon with controllable outer diameter as claimed in any one of claims 2 to 7; A micro-catheter (4); the outer diameter of the micro-catheter (4) is smaller than the inner diameter of the carrier (52).

10. The microcatheter assembly according to claim 9, characterized in that: The micro-catheter (4) is further provided with a limiting ring (41), and the limiting ring (41) is close to the front end of the micro-catheter (4); the maximum outer diameter of the limiting ring (41) is greater than the inner diameter of the supporting member (52).

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