Micro-catheter assembly

Abstract

The invention discloses a microcatheter assembly, and relates to the technical field of medical instruments. A microcatheter assembly includes: a microcatheter; the micro-catheter comprises a first connecting pipe, a corrugated pipe and a second connecting pipe which are connected in sequence; the balloon is arranged on the first connecting tube; at least one control microfilament; the first connecting pipe is further provided with first side holes in one-to-one correspondence with the control microwires. The front end of each control microwire penetrates through the corresponding first side hole and is connected with the inner wall of the second connecting pipe. Through the arrangement of the first connecting pipe, the corrugated pipe, the second connecting pipe and the control microwire, an operator can accurately adjust the space angle of the front end of the microcatheter through the control microwire, so that the space angle of the front end of the microcatheter can be similar to the bent space angle of a narrow part; and therefore, the micro-catheter can easily penetrate through various narrow parts with different bending space angles.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and in particular to a microcatheter assembly. 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 As shown, the inflated balloon 5 can pre-dilate the stenosis 11 of the cerebral artery 1 .

[0004] In the application scenario of arterial blood vessels (for example, cerebral arteries or pulmonary arteries, etc.), due to the different shapes of arterial blood vessels, if the bending spatial angle of the stenosis 11 of the arterial blood vessel is large (for example, a 180° bend or a 360° bend, etc.), although the thinner microguidewire 3 can pass through the stenosis 11 smoothly, the thicker microcatheter 4 has a front end whose spatial angle is too different from the spatial angle of the bend at the stenosis 11. Even with the guidance of the microguidewire 3, it is difficult to advance the microcatheter 4, that is, the microcatheter 4 is difficult to pass through the stenosis 11. Summary of the invention

[0005] The purpose of the present application is to provide a microcatheter assembly to solve the technical problem that if the spatial angle of the front end of the microcatheter is too different from the spatial angle of the bend at the narrow part, the microcatheter is difficult to pass through the narrow part.

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

[0007] A microcatheter assembly, comprising:

[0008] The microcatheter comprises a first connecting tube, a corrugated tube and a second connecting tube connected in sequence;

[0009] A balloon, arranged on the first connecting tube;

[0010] At least one control microwire; the first connecting tube is also provided with first side holes corresponding to the control microwires one by one; the front end of each control microwire passes through the corresponding first side hole and is connected to the inner wall of the second connecting tube.

[0011] As a specific solution in the technical solution of the present application, the first connecting tube is further provided with a second side hole; the second side hole is close to the front end of the microcatheter; the microcatheter assembly further includes:

[0012] Micro guide wire; the micro guide wire is adapted to the second side hole;

[0013] The OCT probe is arranged on the first connecting tube.

[0014] As a specific solution in the technical solution of the present application, the balloon and the microcatheter are an integrated structure; the balloon and the OCT probe are sequentially arranged in the microcatheter, and between the balloon and the OCT probe, the OCT probe is closer to the front end of the microcatheter.

[0015] As a specific solution in the technical solution of the present application, the balloon has a tubular structure and can be movably mounted on the outside of the microcatheter; a closed cavity is formed inside the balloon; the microcatheter assembly also includes a push catheter, which is connected to the rear end of the balloon; the push catheter is communicated with the closed cavity.

[0016] As a specific solution in the technical solution of this application, the balloon includes:

[0017] A carrier; the carrier is a tubular structure;

[0018] The film is arranged outside the carrier; the closed cavity is formed between the carrier and the film.

[0019] As a specific solution in the technical solution of 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.

[0020] As a specific solution in the technical solution of the present application, the maximum outer diameter of the guide part is greater than the outer diameter of the supporting tube; an accommodation groove is formed between the supporting tube and the two guide parts; and the film is stacked in the accommodation groove.

[0021] As a specific solution in the technical solution of 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.

[0022] As a specific scheme in the technical scheme of the present application, the thin film stack forms 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 along the axial array of the carrier; the fracture stress of the connecting microcolumn is less than the cracking stress of the thin 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 thin film, and the other end of each connecting microcolumn is connected to the carrier.

[0023] As a specific solution in the technical solution of the present application, the outer diameter of the microcatheter is smaller than the inner diameter of the carrier; the microcatheter is also provided with a limiting ring, which is close to the front end of the microcatheter; the maximum outer diameter of the limiting ring is larger than the inner diameter of the carrier.

[0024] Compared with the prior art, the beneficial effects of this application are:

[0025] The present application provides a first connecting tube, a bellows, a second connecting tube and a control microwire, so that the operator can accurately adjust the spatial angle of the front end of the microcatheter by controlling the microwire, so that the spatial angle of the front end of the microcatheter can be similar to the spatial angle of the bend at the narrow place, thereby making it easy for the microcatheter to pass through narrow places with various different bending spatial angles. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 Schematic diagram of cerebral artery occlusion;

[0027] Figure 2It is a three-dimensional schematic diagram of a micro-catheter assembly in the prior art;

[0028] Figure 3 To adopt Figure 2 Schematic diagram of the microcatheter assembly in the pre-dilation of the stenosis of the cerebral artery;

[0029] Figure 4 A front view schematic diagram of a microcatheter assembly proposed in an embodiment of the present application;

[0030] Figure 5 A three-dimensional schematic diagram of a microcatheter assembly proposed in an embodiment of the present application;

[0031] Figure 6 A partial cross-sectional schematic diagram of a microcatheter assembly proposed in an embodiment of the present application;

[0032] Figure 7 A three-dimensional schematic diagram of another microcatheter assembly proposed in an embodiment of the present application (OCT probe is not shown);

[0033] Figure 8 for Figure 7 Schematic diagram of the front view of the microcatheter assembly;

[0034] Fig. 9 A schematic cross-sectional view of a balloon proposed in an embodiment of the present application;

[0035] Fig.10 A cross-sectional schematic diagram of another balloon proposed in an embodiment of the present application;

[0036] Fig.11 A three-dimensional schematic diagram of a carrier proposed in an embodiment of the present application;

[0037] Fig.12 A balloon according to an embodiment of the present application is provided Figure 8 Schematic cross-sectional view of the AA line;

[0038] Fig.13 for Fig.12 An enlarged view of part B;

[0039] Fig.14 for Fig.12 After the first inflation of the balloon Figure 8 Schematic cross-sectional view of the AA line;

[0040] Fig.15 for Fig.12 After the second inflation of the middle balloon, Figure 8 Schematic cross-sectional view of the AA line;

[0041] Fig.16 Another balloon proposed in the embodiment of the present application is according to Figure 8 Schematic cross-sectional view of the AA line;

[0042] Fig.17 Another balloon proposed in the embodiment of the present application is according to Figure 8 Schematic cross-sectional view of the AA line;

[0043] Fig.18 for Fig.12 Another enlarged view of part B;

[0044] Fig.19 for Fig.12 After the movable balloon is inflated for the first time, Figure 8 Schematic diagram of the cross-section along line AA.

[0045] In the figure: 1. cerebral artery; 11. stenosis; 2. abnormal mass; 3. micro guide wire; 4. micro catheter; 41. limiting ring; 42. second side hole; 43. first connecting tube; 44. bellows; 45. second connecting tube; 46. first side hole; 5. balloon; 51. closed cavity; 52. supporting member; 521. supporting tube; 522. guide part; 523. placement groove; 53. film; 531. connecting micro column; 532. micro titanium alloy wire; 533. first laminated membrane; 534. second laminated membrane; 6. push catheter; 7. OCT probe; 8. control micro wire. DETAILED DESCRIPTION

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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 proposed in the present application. It does not mean that the microcatheter assembly proposed in the present application is only applicable to the application scenario of cerebral artery occlusion. It should be understood that the microcatheter assembly proposed in the present application is 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.

[0051] 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, the application scenario of the microcatheter assembly can be cerebral artery stenosis or cerebral artery occlusion, which will not be described in detail later.

[0052] 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.

[0053] In order to solve the technical problem that if the spatial angle of the front end of the microcatheter is too different from the spatial angle of the bend at the stenosis, the microcatheter is difficult to pass through the stenosis, the present application proposes a microcatheter assembly, which includes a microcatheter 4, a balloon 5 and at least one control microwire 8. Figure 5 and Figure 6 As shown, the micro-catheter 4 includes a first connecting tube 43, a corrugated tube 44 and a second connecting tube 45 connected in sequence. The first connecting tube 43 is also provided with a first side hole 46 corresponding to the control micro-wire 8. Figure 6 As shown, the front end of each control microwire 8 passes through the corresponding first side hole 46 and is connected to the inner wall of the second connecting tube 45. Figure 5 As shown, the balloon 5 is arranged on the first connecting tube 43 .

[0054] When in use, if the spatial angle of the front end of the microcatheter 4 is significantly different from the spatial angle of the bend at the stenosis 11, the spatial angle of the front end of the microcatheter 4 can be adjusted by controlling the microwire 8 so that the spatial angle of the front end of the microcatheter 4 is similar to the spatial angle of the bend at the stenosis 11, thereby making it easier for the microcatheter 4 to pass through the stenosis 11. Figure 6 As shown in FIG. 1 , in this embodiment, if a thrust is applied to the control microwire 8, the portion of the control microwire 8 entering the microcatheter 4 will increase, that is, the control microwire 8 can also apply a thrust to the second connecting tube 45. If the control microwire 8 applies a thrust to the second connecting tube 45, the bellows 44 will be unevenly stressed on both sides, as shown in FIG. Figure 6 As shown, the bellows 44 bends along the direction E. If a pulling force is applied to the control microwire 8, the portion of the control microwire 8 entering the microcatheter 4 will be reduced, that is, the control microwire 8 can also apply a pulling force to the second connecting tube 45. If the control microwire 8 applies a pulling force to the second connecting tube 45, the bellows 44 will be bent due to the unbalanced forces on both sides. Figure 6 As shown, bending occurs along direction F.

[0055] In this embodiment, only one control microwire 8 may be provided. When in use, the microcatheter 4 may be rotated first based on the spatial position of the stenosis 11, and then the bending spatial angle of the front end of the microcatheter 4 may be adjusted by controlling the microwire 8, so that the spatial angle of the front end of the microcatheter 4 is similar to the bending spatial angle of the stenosis 11. In order to adjust the spatial angle of the front end of the microcatheter 4 based on the spatial position of the stenosis 11 without rotating the microcatheter 4, in one embodiment of the present application, Figure 5 As shown, a plurality of control microwires 8 may be provided. It should be noted that the more control microwires 8 there are, the easier it is for the operator to control the spatial angle of the front end of the microcatheter 4, that is, the easier it is to make the spatial angle of the front end of the microcatheter 4 similar to the spatial angle of the bend of the narrow part 11 without rotating the microcatheter 4.

[0056] In this embodiment, the first connecting tube 43 is a tube that can be bent, but the hardness of the first connecting tube 43 is greater than the hardness of the second connecting tube 45. If the hardness of the first connecting tube 43 is greater than the hardness of the second connecting tube 45, the harder first connecting tube 43 can push the second connecting tube 45 to move in the cerebral artery 1. The second connecting tube 45 is located at the front end of the microcatheter 4. Since the hardness of the second connecting tube 45 is less than the hardness of the first connecting tube 43, the microcatheter 4 is not easy to damage the inner wall of the cerebral artery 1 during the movement of the cerebral artery 1.

[0057] In this embodiment, in order to prevent the first connecting tube 43, the bellows 44 and the second connecting tube 45 from breaking due to poor connection strength during use, the first connecting tube 43, the bellows 44 and the second connecting tube 45 can be an integrally formed structure. The integrally formed first connecting tube 43, the bellows 44 and the second connecting tube 45 have good connection strength and are not easy to break during use.

[0058] The embodiments proposed in the present application enable the operator to precisely adjust the spatial angle of the front end of the microcatheter by controlling the microwire through the arrangement of the first connecting tube, the bellows, the second connecting tube and the control microwire, so that the spatial angle of the front end of the microcatheter can be similar to the spatial angle of the bend at the narrow place, thereby making it easy for the microcatheter to pass through narrow places with various bending spatial angles.

[0059] It should be noted that after the pre-dilation of the stenosis 11 of the cerebral artery 1 is completed, the microcatheter 4 needs to be extracted from the cerebral artery 1, and then the optical coherence tomography (OCT) probe is placed in the stenosis 11 after the pre-dilation is completed, and then the stenosis 11 is scanned by the OCT probe. If the size of the stenosis 11 after pre-dilation does not meet the requirements, it is also necessary to extract the OCT probe from the cerebral artery 1, and then insert the microcatheter 4 carrying the balloon 5 into the stenosis 11 to pre-dilate the stenosis 11 until the OCT probe detects that the size of the stenosis 11 after pre-dilation meets the requirements. The above-mentioned operation steps are relatively cumbersome, resulting in a long operation time and high difficulty in operation. 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 microcatheter 4 or the OCT probe increases the risk of damage to the inner wall of the cerebral artery 1.

[0060] In order to solve the technical problem of complicated operation steps and high difficulty in operation when using a balloon and an OCT probe to pre-dilate the stenosis of the cerebral artery, in one embodiment of the present application, the microcatheter assembly may further include a micro guidewire 3 and an OCT probe 7. Figure 5 As shown, the first connecting tube 43 is provided with a second side hole 42, and the balloon 5 and the OCT probe 7 are also provided on the first connecting tube 43. When in use, the microguidewire 3 is passed through the second side hole 42 into the interior of the microcatheter 4, and then the microguidewire 3 is passed out from the front end of the microcatheter 4, and then the microguidewire 3 can guide the microcatheter 4 so that the microcatheter 4 can move smoothly in the cerebral artery 1. In this embodiment, the microguidewire 3 is adapted to the second side hole 42. The adaptation of the microguidewire 3 to the second side hole 42 means that the microguidewire 3 can enter the interior of the microcatheter 4 through the second side hole 42, for example: the outer diameter of the microguidewire 3 can be equal to the inner diameter of the second side hole 42, or the outer diameter of the microguidewire 3 is smaller than the inner diameter of the second side hole 42.

[0061] During use, if the stenosis 11 in the cerebral artery 1 needs to be pre-dilated, firstly insert the micro-guidewire 3 into the interior of the micro-catheter 4 through the second side hole 42, and then insert the micro-guidewire 3 out of the front end of the micro-catheter 4; further, the micro-guidewire 3 is passed through the stenosis 11 of the cerebral artery 1; further, the micro-catheter 4 is passed through the stenosis 11 through the guidance of the micro-guidewire 3 until the balloon 5 is located at the stenosis 11 of the cerebral artery 1; further, a medium is filled into the balloon 5 so that the balloon 5 can be inflated, and then the stenosis 11 is pre-dilated; after the pre-dilation is completed, the medium in the balloon 5 is extracted so that the balloon 5 returns to its original state, and then the OCT probe 7 is moved to the stenosis 11 of the cerebral artery 1 through the micro-catheter 4 to scan the stenosis 11. If the size of the stenosis 11 after pre-dilation does not meet the requirements, the balloon 5 is moved to the stenosis 11 of the cerebral artery 1 for pre-dilation operation until the OCT probe 7 detects that the size of the stenosis 11 after pre-dilation meets the requirements.

[0062] In the embodiment of the microcatheter assembly proposed in the present application, both the balloon and the OCT probe are arranged in the microcatheter. When in use, there is no need to frequently extract or insert the balloon or the OCT probe from the cerebral artery. The balloon or the OCT probe only needs to be moved a small distance (a dozen or tens of millimeters) in the cerebral artery. Compared with the prior art, the operation difficulty is small and the operation time is short, which can reduce the risk of damage to the inner wall of the patient's cerebral artery and other risks borne by the patient during surgery.

[0063] In this embodiment, the second side hole 42 can be at any suitable position on the microcatheter 4 without affecting the OCT probe 7. In one embodiment of the present application, the second side hole 42 can be close to the front end of the microcatheter 4. It should be noted that if the second side hole 42 is too close to the front end of the microcatheter 4, that is, the length of the entity part of the microcatheter 4 between the second side hole 42 and the front end (hereinafter referred to as the first part) (that is, as shown in FIG. Figure 4 If the distance S1 shown in the figure is short, the microguidewire 3 is likely to break the first part during the passage of the microguidewire 3 through the second side hole 42 because the first part is short, that is, the strength of the first part along the axial direction of the microcatheter 4 is poor. If the first part of the microcatheter 4 is broken, the microguidewire 3 must be separated from the microcatheter 4. If the microguidewire 3 is separated from the microcatheter 4, the microguidewire 3 cannot guide the microcatheter 4, that is, the front end of the microcatheter 4 cannot smoothly advance in the cerebral artery 1. In order to avoid the first part of the microcatheter 4 from breaking during use, in an embodiment of the present application, the second side hole 42 close to the front end of the microcatheter 4 can refer to the straight-line distance between the axial centerline of the second side hole 42 and the front end face of the microcatheter 4 (that is, as shown in the figure). Figure 4The distance S1 shown, hereinafter referred to as the first distance) is greater than or equal to 1.0 mm and less than or equal to 3.0 mm. In this embodiment, the first distance can be any one of 1.0 mm, 1.2 mm, 1.4 mm, 1.6 mm, 1.8 mm, 2.0 mm, 2.2 mm, 2.4 mm, 2.6 mm, 2.8 mm and 3.0 mm, or any distance between two adjacent distances mentioned above.

[0064] In this embodiment, since the OCT probe 7 is a mature technology, it is not described in detail. It should be noted that since the OCT probe 7 is relatively precise, if the OCT probe 7 is close to the second side hole 42, the micro-guide wire 3 is likely to damage the OCT probe 7 during the passage of the second side hole 42. In order to avoid damage to the OCT probe 7, in the embodiment of the present application, the distance between the front end face of the OCT probe 7 and the axis of the second side hole 42 (i.e., Figure 4 The distance S2 shown, hereinafter referred to as the second distance) can be greater than or equal to 0.5 mm and less than or equal to 1.5 mm. In this embodiment, the second distance can be any one of 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1.0 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm and 1.5 mm, or any distance between two adjacent distances mentioned above.

[0065] It should be noted that only if the length of the OCT probe 7 is greater than the length of the stenosis 11, can the OCT probe 7 completely scan the stenosis 11. That is to say, in this embodiment, the longer the length of the OCT probe 7, the better. However, if the length of the OCT probe 7 is longer, after the OCT probe 7 is set in the microcatheter 4, the strength of the part of the microcatheter 4 located at the OCT probe 7 will be weaker, and therefore it will be easier to break. In order to make the OCT probe 7 suitable for scanning most of the stenosis 11 in the cerebral artery 1 and to avoid the microcatheter 4 from breaking during use, in one embodiment of the present application, the length of the OCT probe 7 (that is, as shown in FIG. 1 ) is greater than the length of the OCT probe 7. Figure 4 The length S3) shown can be greater than or equal to 15 mm and less than or equal to 20 mm. In this embodiment, the length of the OCT probe 7 can be any one of 15 mm, 16 mm, 17 mm, 18 mm, 19 mm and 20 mm, or any length between two adjacent lengths mentioned above.

[0066] In the embodiments of the present application, Figure 4 or Figure 5 As shown, the balloon 5 and the microcatheter 4 can be an integrated structure. The balloon 5 and the OCT probe 7 are sequentially arranged on the microcatheter 4, and between the balloon 5 and the OCT probe 7, the OCT probe 7 is closer to the front end of the microcatheter 4.

[0067] It should be noted that if Figure 4 or Figure 5 As shown, if the microcatheter 4 and the balloon 5 are an integrated structure, the balloon 5 is at a certain distance from the front end of the microcatheter 4 due to the presence of the OCT probe 7. If the stenosis 11 is located at the end of the cerebral artery 1, during 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 accommodation space at the end of the cerebral artery 1 (that is, various capillaries) is limited, 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.

[0068] In order to prevent the front end of the microcatheter 4 from damaging the inner wall of the end of the cerebral artery 1 or causing the cerebral artery 1 to rupture when the stenosis 11 is located at the end of the cerebral artery 1, in one embodiment of the present application, Fig. 9 or Fig.10 As shown, the balloon 5 is a tubular structure, and a closed cavity 51 is formed inside the balloon 5. Figure 7 and Figure 8 As shown, the balloon 5 can be movably sleeved on the outside of the microcatheter 4. The microcatheter assembly also includes a push catheter 6, which is connected to the rear end of the balloon 5 and communicates with the closed cavity 51.

[0069] 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 balloon 5 is moved to the stenosis 11 of the cerebral artery 1 through the push catheter 6; finally, a medium (for example, air or saline) is filled into the closed cavity 51 in the balloon 5 through the push catheter 6 to inflate the balloon 5, thereby pre-dilatating the stenosis 11 of the cerebral artery 1.

[0070] 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, 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, 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 in detail here.

[0071] In this embodiment, since the balloon 5 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 balloon 5 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 balloon 5. Compared with the embodiment in which the microcatheter and the balloon are integrated, the microcatheter assembly proposed in this embodiment can be applicable to the application scenario in which the stenosis is located at the end of the cerebral artery.

[0072] In the embodiment of the present application, the push catheter 6 is a catheter that can apply a push force to the balloon 5, so the push catheter 6 needs to have a certain rigidity. If the push catheter 6 is too rigid, the push catheter 6 is likely to damage the blood vessel 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 likely to damage the blood vessel 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.

[0073] In the embodiments of the present application, there is no limitation on the shape and structure of the balloon 5, as long as the balloon 5 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 balloon 5 can be at least as shown in the following two embodiments.

[0074] Balloon Embodiment 1

[0075] In this embodiment, the balloon 5 can be Fig. 9 As shown, it can be a one-piece balloon with uniform wall thickness. As can be seen from the foregoing, the balloon 5 needs to be able to move along the microcatheter 4 under the pushing action of the push catheter 6, that is, the balloon 5 itself needs to have good rigidity. After reaching the stenosis 11, the balloon 5 needs to be inflated, that is, the balloon 5 itself also needs to have good flexibility.

[0076] Example 2 of the balloon

[0077] 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. In order to improve the use effect of the balloon 5, in this embodiment, the balloon 5 includes a carrier 52 and a film 53. Fig.10 As shown, the carrier 52 is a tubular structure. The film 53 is arranged outside the carrier 52 , and the closed cavity 51 is formed between the carrier 52 and the film 53 .

[0078] When in use, the support member 52 is mainly used to provide rigidity so that the balloon 5 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 balloon 5 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 through the arrangement of the support member 52 and the film 53. 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.

[0079] In this embodiment, the support member 52 can be made of the same material as the film 53. If the support member 52 and the film 53 are made of the same material, the thickness of the support member 52 along the radial direction of the balloon 5 can 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.

[0080] 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 Fig.11 The support tube 521 shown in FIG. 5 , or the support member 52 may be as shown in FIG. Fig.11 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.

[0081] 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.

[0082] 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 5, that is, the film 53 is not easy to damage the inner wall of the cerebral artery 1, in this embodiment, Fig.11As 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 balloon 5. 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.

[0083] In the embodiments of the present application, Fig.10 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.12 As shown, the film 53 may also be a film with poor elasticity. During production, the film 53 may be stacked and arranged in the placement groove 523. When the medium is filled into the closed cavity 51, the film 53 may also swell, thereby pre-dilatating the stenosis 11. Thus, the second embodiment of the balloon is introduced.

[0084] 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.

[0085] 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.16 As shown, a plurality of titanium alloy microwires 532 (i.e., Fig.16 Or Fig.17 Each titanium alloy wire 532 is used to determine the current state of the film 53 (e.g., Fig.14 and Fig.15 The used state shown) and the initial state (that is, Fig.16If 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.

[0086] In this embodiment, Fig.16 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.16 In this embodiment, the initial stacking form can also be Fig.17 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.17 The initial stacking morphology is shown.

[0087] It should be noted that in the embodiments of the present application, only Fig.16 and Fig.17 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.16 or Fig.17 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.

[0088] It should be clear that if Figure 1 As shown, in the application scenario where the abnormal mass 2 in the cerebral artery 1 is relatively large and the stenosis 11 is relatively small, if the balloon 5 is used to expand the size of the stenosis 11 at one time, 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 stenosis 11 is relatively small, it is generally necessary to use a balloon 5 with a smaller size after inflation (hereinafter referred to as the first balloon) to perform a first pre-expansion of the stenosis 11, and then use a balloon 5 with a larger size after inflation (hereinafter referred to as the second balloon) to perform a second pre-expansion of the stenosis 11.

[0089] In the prior art, the operating steps for performing two pre-dilations on the stenosis 11 are as follows: first, under 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 perform the first pre-dilation on the stenosis 11; then, the micro-catheter 4 carrying the first balloon is withdrawn from the cerebral artery 1; finally, under 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 perform the second pre-dilation on the stenosis 11.

[0090] It should be understood that the prior art procedure of performing two pre-dilations on the stenosis 11 is relatively cumbersome, resulting in a long operation time and high difficulty. It is easy to understand that the longer the operation time, the greater the risk borne by the patient, and the multiple withdrawal and insertion of the microcatheter 4 increases the risk of damaging the inner wall of the cerebral artery 1. In order to reduce the above risks, in one embodiment of the present application, Fig.12 As shown, the film 53 may be stacked to form a plurality of stacked portions. Fig.13 As shown, each stacked portion includes at least 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 portion. A plurality of connecting micro-pillars 531 are formed between the first stacked film 533 and the second stacked film 534, and each connecting micro-pillar 531 is distributed in an axial array along the carrier 52. One end of each connecting micro-pillar 531 is connected to the first stacked film 533, and the other end of each connecting micro-pillar 531 is connected to the second stacked film 534. The fracture stress of the connecting micro-pillar 531 is less than the cracking stress of the film 53.

[0091] When in use, the microcatheter 4 can be guided through the narrow part 11 by the micro-guidewire 3; then, the balloon 5 carrying the film 53 can be moved to the narrow part 11 by the push catheter 6 under the guidance of the microcatheter 4; further, a medium with a pressure less than the fracture stress of the connecting micro-pillar 531 is injected into the closed cavity 51 by the push catheter 6, and then Fig.12 The film 53 shown can be expanded, and the expanded film 53 is as shown in FIG. Fig.14 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.15As shown, the stenosis 11 can be pre-dilated for the second time. That is, in this embodiment, two pre-dilations of different sizes of the stenosis 11 can be achieved by 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, that is, reduce the risk borne by the patient during the operation.

[0092] In another embodiment of the present application, Fig.18 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.12 The film 53 shown can be expanded, and the expanded film 53 is as shown in FIG. Fig.19 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.15 As shown, the stenosis 11 can be pre-dilated a second time.

[0093] 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 balloon 5 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.12 As shown, the outer diameter of the microcatheter 4 (i.e. Fig.12 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.12 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.

[0094] 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 (that is, various capillaries) 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 closer to the stenosis 11 during use. If the front end of the microcatheter 4 is closer to the stenosis 11, there is a risk that the balloon 5 will be separated from the microcatheter 4 when the balloon 5 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 balloon 5. If the balloon 5 is separated from the microcatheter 4, it is difficult to remove the balloon 5 from the cerebral artery 1 without damaging the cerebral artery 1. In order to avoid the balloon 5 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 7 and Figure 8 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 greater than the inner diameter of the balloon 5 (that is, as shown in FIG. Fig.12 Inner diameter D) shown.

[0095] 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 balloon 5, the balloon 5 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 is the distance between the front end face of the limiting ring 41 and the front end face of the microcatheter 4 (i.e., Figure 8 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.

[0096] In the embodiment of the present application, the limiting ring 41 may be any ring that can limit the movement of the balloon 5. For example, the limiting ring 41 may be a ring 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 may also be Figure 7 and Figure 8 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.

[0097] The embodiments proposed in the present application enable the operator to precisely adjust the spatial angle of the front end of the microcatheter by controlling the microwire through the arrangement of the first connecting tube, the bellows, the second connecting tube and the control microwire, so that the spatial angle of the front end of the microcatheter can be similar to the spatial angle of the bend at the narrow place, thereby making it easy for the microcatheter to pass through narrow places with various bending spatial angles.

[0098] 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 microcatheter assembly, characterized in that: include: A microcatheter (4); the microcatheter (4) comprises a first connecting tube (43), a corrugated tube (44) and a second connecting tube (45) which are connected in sequence; A balloon (5) arranged on the first connecting tube (43); At least one control microwire (8); the first connecting tube (43) is also provided with first side holes (46) corresponding to the control microwires (8); the front end of each control microwire (8) passes through the corresponding first side hole (46) and is connected to the inner wall of the second connecting tube (45).

2. The microcatheter assembly according to claim 1, characterized in that: The first connecting tube (43) is also provided with a second side hole (42); the second side hole (42) is close to the front end of the microcatheter (4); the microcatheter assembly further comprises: A micro guide wire (3); the micro guide wire (3) is adapted to the second side hole (42); The OCT probe (7) is arranged on the first connecting tube (43).

3. The microcatheter assembly according to claim 2, characterized in that: The balloon (5) and the microcatheter (4) are an integrated structure; the balloon (5) and the OCT probe (7) are sequentially arranged on the microcatheter (4), and between the balloon (5) and the OCT probe (7), the OCT probe (7) is closer to the front end of the microcatheter (4).

4. The microcatheter assembly according to claim 1, characterized in that: The balloon (5) is of tubular structure, and can be movably sleeved on the outside of the microcatheter (4); a closed cavity (51) is formed inside the balloon (5); the microcatheter assembly further comprises a push catheter (6), which is connected to the rear end of the balloon (5); the push catheter (6) is in communication with the closed cavity (51).

5. The microcatheter assembly according to claim 4, characterized in that: The balloon (5) comprises: A carrier (52); the carrier (52) is a tubular structure; The film (53) is arranged outside the carrier (52); the closed cavity (51) is formed between the carrier (52) and the film (53).

6. The microcatheter assembly according to claim 5, 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).

7. The microcatheter assembly according to claim 6, characterized in that: The maximum outer diameter of the guide portion (522) is greater than the outer diameter of the supporting tube (521); a placement groove (523) is formed between the supporting tube (521) and the two guide portions (522); and the film (53) is stacked and arranged in the placement groove (523).

8. The microcatheter assembly according to claim 7, 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.

9. The microcatheter assembly according to claim 8, characterized in that: The film (53) is stacked to form a plurality of stacked parts; each stacked part includes at least 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 part; a plurality of connecting microcolumns (531) are arranged between each stacked part and the supporting member (52), and each connecting microcolumn (531) is 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).

10. The microcatheter assembly according to any one of claims 5 to 8, characterized in that: The outer diameter of the microcatheter (4) is smaller than the inner diameter of the carrier (52); the microcatheter (4) is also provided with a limit ring (41), and the limit ring (41) is close to the front end of the microcatheter (4); the maximum outer diameter of the limit ring (41) is greater than the inner diameter of the carrier (52).

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