A microcatheter assembly

Abstract

The present application discloses a microcatheter assembly, which relates to the technical field of medical devices. The microcatheter assembly includes: a microcatheter; the microcatheter includes a first connecting tube, a corrugated tube and a second connecting tube which are connected in sequence; a balloon disposed on the first connecting tube; at least one control wire; the first connecting tube is further provided with first side holes corresponding one-to-one to the control wires; the front ends of the respective control wires pass through the corresponding first side holes and are connected to the inner wall of the second connecting tube. Through the arrangement of the first connecting tube, the corrugated tube, the second connecting tube and the control wires, the operator can accurately adjust the spatial angle of the front end of the microcatheter through the control wires, 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 part, and further the microcatheter can easily pass through the narrow parts with various different spatial angles of bends.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and particularly to a microcatheter assembly. Background Art

[0002] Cerebral artery occlusion is a serious cerebrovascular disease, which refers to the blockage or occlusion of intracranial arteries, resulting in severe ischemia and hypoxia in the blood supply areas of the brain, cerebellum or brainstem. Generally, as Figure 1 shown, cerebral artery occlusion is caused by the attachment of abnormal masses 2 (such as atherosclerotic plaques or abnormal hyperplastic masses, etc.) to the inner wall of cerebral artery 1. The abnormal mass 2 causes a stenosis 11 to form inside the cerebral artery 1. If the diameter of the stenosis 11 is extremely small or zero, it will cause the cerebral artery 1 to become occluded, and then it will be difficult for the heart to supply blood to the brain tissue. Over time, the patient will experience symptoms of cerebral infarction such as dizziness, headache, visual impairment, aphasia, limb impairment, etc. In severe cases, coma may occur, threatening life. To solve this technical problem, the prior art generally adopts the method of setting a stent at the stenosis 11 to support the cerebral artery 1, so as to ensure that the blood in the cerebral artery 1 can smoothly pass through the stenosis 11.

[0003] Specifically, before setting a stent at the stenosis 11, a 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. The microcatheter assembly of the prior art is as Figure 2 shown, including a microguide wire 3, a microcatheter 4 and a balloon 5. The microcatheter 4 and the balloon 5 are of an integrated structure; the microcatheter 4 is movably sleeved outside the microguide wire 3. When in use, first pass the microguide wire 3 through the stenosis 11 of the cerebral artery 1; then pass the microcatheter 4 along the microguide wire 3 through the stenosis 11 of the cerebral artery 1 until the balloon 5 is located at the stenosis 11 of the cerebral artery 1; finally, fill the balloon 5 with a medium (such as air or normal saline, etc.) through the microcatheter 4, so that the balloon 5 can expand, and then as Figure 3 shown, the expanded balloon 5 can pre-expand the stenosis 11 of the cerebral artery 1.

[0004] In the application scenarios of arterial blood vessels (such as cerebral arteries or pulmonary arteries, etc.), due to the various shapes of arterial blood vessels, if the bending space angle of the stenosis 11 of the arterial blood vessel is relatively large (for example, 180° bending or 360° bending, etc.), although the thinner microguide wire 3 can smoothly pass through the stenosis 11, the thicker microcatheter 4 is difficult to be advanced due to the excessive difference between the space angle at its front end and the bending space angle of the stenosis 11, that is, it is difficult for the microcatheter 4 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 it is difficult for the microcatheter to pass through a stenosis if the spatial angle at the front end of the microcatheter has a too large difference from the spatial angle at which it bends at the stenosis.

[0006] To achieve the above object, the present application provides the following technical solutions:

[0007] A microcatheter assembly, comprising:

[0008] A microcatheter; the microcatheter includes a first connecting tube, a bellows tube, and a second connecting tube connected in sequence;

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

[0010] At least one control microfilament; the first connecting tube is further provided with first side holes corresponding one-to-one to the control microfilaments; the front ends of the respective control microfilaments pass through the corresponding first side holes and are 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 second side holes; the second side holes are close to the front end of the microcatheter; the microcatheter assembly further includes:

[0012] A microguide wire; the microguide wire is adapted to the second side holes;

[0013] An OCT probe, disposed on the first connecting tube.

[0014] As a specific solution in the technical solution of the present application, the balloon and the microcatheter are of an integral structure; the balloon and the OCT probe are sequentially disposed on the microcatheter, and among 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 is in a tubular structure, and the balloon can be movably sleeved outside the microcatheter; a sealed cavity is formed inside the balloon; the microcatheter assembly further includes a push catheter, and the push catheter is connected to the rear end of the balloon; the push catheter is in communication with the sealed cavity.

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

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

[0018] A film, disposed outside the carrier; the sealed cavity is formed between the carrier and the film.

[0019] As a specific solution in the technical solution of the present application, the carrier includes a carrier tube; guiding portions are provided at both ends of the carrier tube; the outer diameter of the guiding portion decreases along a first direction; the first direction is parallel to the axial direction of the carrier tube and points from the guiding portion to the carrier tube.

[0020] As a specific solution in the technical solution of the present application, the maximum outer diameter of the guiding portion is greater than the outer diameter of the carrier tube; an accommodation groove is formed between the carrier tube and the two guiding portions; the thin film is stacked in the accommodation groove.

[0021] As a specific solution in the technical solution of the present application, multiple micro-titanium alloy wires are arranged inside the thin film; if the current state of the thin film is different from the initial state, elastic potential energy is formed in each micro-titanium alloy wire, and the elastic potential energy is used to make the thin film tend to change from the current state to the initial state.

[0022] As a specific solution in the technical solution of the present application, the thin film is stacked to form multiple stacked portions; each stacked portion 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 portion; multiple connecting micro-columns are provided between each stacked portion and the carrier, and the connecting micro-columns are arranged in an array along the axial direction of the carrier; the fracture stress of the connecting micro-columns is less than the cracking stress of the thin film; one end of each connecting micro-column is connected to the first stacked film, and the other end of each connecting micro-column is connected to the second stacked film; or, one end of each connecting micro-column is connected to the thin film, and the other end of each connecting micro-column 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 further provided with a limiting ring near the front end of the microcatheter; the maximum outer diameter of the limiting ring is greater than the inner diameter of the carrier.

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

[0025] Through the arrangement of the first connecting tube, the corrugated tube, the second connecting tube and the control micro-wire, the operator can accurately adjust the spatial angle of the front end of the microcatheter through the control micro-wire, 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 part, and then the microcatheter can easily pass through the narrow parts with various different bent spatial angles. Description of the Drawings

[0026] Figure 1 It is a schematic diagram of cerebral artery occlusion;

[0027] Figure 2A three-dimensional schematic diagram of a microcatheter assembly in the prior art;

[0028] Figure 3 It is for Figure 2 A schematic diagram of pre-dilating a stenosis of a cerebral artery using the microcatheter assembly in;

[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 not shown);

[0033] Figure 8 It is for Figure 7 A front view schematic diagram of the microcatheter assembly in;

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

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

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

[0037] Figure 12 A cross-sectional schematic diagram of a balloon proposed in an embodiment of the present application along the A-A line in; Figure 8 ;

[0038] Figure 13 It is for Figure 12 An enlarged view of part B in;

[0039] Figure 14 It is for Figure 12 After the first inflation of the balloon in, along the A-A line in; Figure 8 ;

[0040] Figure 15 It is for Figure 12 After the second inflation of the balloon in, along the A-A line in; Figure 8 ;

[0041] Figure 16 Another balloon proposed in an embodiment of the present application alongFigure 8 Schematic cross-sectional view along line A-A in

[0042] Figure 17 Another balloon proposed in the embodiment of the present application is in accordance with Figure 8 Schematic cross-sectional view along line A-A in

[0043] Figure 18 is Figure 12 Another enlarged view of part B in

[0044] Figure 19 is Figure 12 Another schematic cross-sectional view along line A-A in Figure 8 after the first inflation of the movable balloon in

[0045] In the figure: 1, cerebral artery; 11, stenosis; 2, abnormal mass; 3, micro-guide wire; 4, micro-catheter; 41, limit ring; 42, second side hole; 43, first connecting tube; 44, corrugated tube; 45, second connecting tube; 46, first side hole; 5, balloon; 51, sealed cavity; 52, carrier; 521, carrier tube; 522, guiding part; 523, placement groove; 53, film; 531, connecting micro-columns; 532, micro-titanium alloy wire; 533, first laminated film; 534, second laminated film; 6, push catheter; 7, OCT probe; 8, control micro-wire. Detailed implementation manners

[0046] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application.

[0047] It should be noted that in the description of the present application, the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present application.

[0048] In addition, it should be understood that, for the convenience of description, the dimensions of the various components shown in the accompanying drawings are not drawn in actual proportional relationship. For example, the thickness or width of some layers may be exaggerated relative to other layers.

[0049] It should be noted that similar reference numerals and letters represent similar items in the following drawings. Therefore, once an item is defined or described in one drawing, it will not be necessary to further specifically discuss and describe it in the description of subsequent drawings.

[0050] Before understanding the embodiments of the present application, it should be clear that in the embodiments below of the present application, only the application scenario of cerebral artery occlusion is taken as an example to illustrate the microcatheter assembly proposed by the present application. It does not mean that the microcatheter assembly proposed by the present application is only applicable to the application scenario of cerebral artery occlusion. It should be understood that the microcatheter assembly proposed by 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, etc., will not be listed and elaborated one by one here.

[0051] It should be noted that in this embodiment, as Figure 1 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 elaborated later.

[0052] Before understanding the embodiments of the present application, it should also be clear that most of the parts in the microcatheter assembly (for example: the microguide wire 3, the microcatheter 4 or the balloon 5, etc.) have two ends. In the embodiments below of the present application, the two ends of a part are respectively defined as the front end and the rear end, where the front end refers to the end of the part that first enters the cerebral artery 1 during use, and the rear end refers to the end of the part that does not enter or enters the cerebral artery 1 later during use, which will not be elaborated later.

[0053] To solve the technical problem in the background art 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, it is difficult for the microcatheter 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 microfilament 8. As Figure 5 and Figure 6 shown, the microcatheter 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 first side holes 46 corresponding one-to-one to the control microfilaments 8. As Figure 6 shown, the front ends of the respective control microfilaments 8 pass through the corresponding first side holes 46 and are connected to the inner wall of the second connecting tube 45. As Figure 5 shown, the balloon 5 is arranged on the first connecting tube 43.

[0054] During use, if the spatial angle at the front end of the microcatheter 4 differs significantly from the spatial angle of the bend at the stenosis 11, the spatial angle at the front end of the microcatheter 4 can be adjusted by controlling the microfilament 8 so that the spatial angle at 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. As Figure 6 shown, in this embodiment, if a thrust is applied to the control microfilament 8, it will definitely cause an increase in the portion of the control microfilament 8 that enters the interior of the microcatheter 4, that is, the control microfilament 8 can also apply a thrust to the second connecting tube 45. If the control microfilament 8 applies a thrust to the second connecting tube 45, then due to the uneven force on both sides of the corrugated tube 44, it will be as Figure 6 shown and bend along direction E. If a pulling force is applied to the control microfilament 8, it will definitely cause a decrease in the portion of the control microfilament 8 that enters the interior of the microcatheter 4, that is, the control microfilament 8 can also apply a pulling force to the second connecting tube 45. If the control microfilament 8 applies a pulling force to the second connecting tube 45, then due to the uneven force on both sides of the corrugated tube 44, it will be as Figure 6 shown and bend along direction F.

[0055] In this embodiment, only one control microfilament 8 can be provided. During use, the microcatheter 4 can be rotated first based on the spatial position of the stenosis 11, and then the bending spatial angle at the front end of the microcatheter 4 can be adjusted by controlling the microfilament 8 so that the spatial angle at the front end of the microcatheter 4 is similar to the spatial angle of the bend at the stenosis 11. In order to be able to adjust the spatial angle at the front end of the microcatheter 4 based on the spatial position of the stenosis 11 without rotating the microcatheter 4, in an embodiment of the present application, as Figure 5 shown, multiple control microfilaments 8 can be provided. It should be noted that the more the number of control microfilaments 8, the more convenient it is for the operator to control the spatial angle at the front end of the microcatheter 4, that is, it is easier to make the spatial angle at the front end of the microcatheter 4 similar to the spatial angle of the bend at the stenosis 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, then 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, during the movement of the microcatheter 4 in the cerebral artery 1, the inner wall of the cerebral artery 1 is not easily damaged.

[0057] In this embodiment, to avoid breakage of the first connecting pipe 43, the corrugated pipe 44, and the second connecting pipe 45 due to poor connection strength during use, the first connecting pipe 43, the corrugated pipe 44, and the second connecting pipe 45 can be an integrally formed structure. The integrally formed first connecting pipe 43, corrugated pipe 44, and second connecting pipe 45 have better connection strength and are not easily broken during use.

[0058] In the embodiment proposed by this application, through the settings of the first connecting pipe, the corrugated pipe, the second connecting pipe, and the control microfilament, an operator can precisely adjust the spatial angle of the front end of the microcatheter through the control microfilament, so that the spatial angle of the front end of the microcatheter can be similar to the spatial angle of the bend at the stenosis, thereby making it easy for the microcatheter to pass through stenoses with various different spatial angles of bends.

[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 withdrawn from the cerebral artery 1, and then an Optical Coherence Tomography (OCT) probe is inserted into the pre-dilated stenosis 11, and then the stenosis 11 is scanned through the OCT probe. If the size of the stenosis 11 after pre-dilation does not meet the requirements, the OCT probe also needs to be withdrawn from the cerebral artery 1, and then the microcatheter 4 carrying the balloon 5 is inserted 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 operation steps are relatively cumbersome, resulting in a long operation time and a large 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 withdrawing and inserting the microcatheter 4 or the OCT probe also correspondingly increases the risk of damage to the inner wall of the cerebral artery 1.

[0060] To solve the technical problems of complex operation steps and large operation difficulty when pre-dilating the stenosis of the cerebral artery using a balloon and an OCT probe, in an embodiment of this application, the microcatheter assembly can further include a microguide wire 3 and an OCT probe 7. As Figure 5 shown, the first connecting pipe 43 is provided with a second side hole 42, and the balloon 5 and the OCT probe 7 are also both arranged on the first connecting pipe 43. During use, the microguide wire 3 is passed through the second side hole 42 into the interior of the microcatheter 4, and then the microguide wire 3 passes out from the front end of the microcatheter 4. Furthermore, the microguide wire 3 can guide the microcatheter 4 so that the microcatheter 4 can move smoothly in the cerebral artery 1. In this embodiment, the microguide wire 3 is adapted to the second side hole 42. The microguide wire 3 being adapted to the second side hole 42 means that the microguide wire 3 can enter the interior of the microcatheter 4 through the second side hole 42. For example: the outer diameter of the microguide wire 3 can be equal to the inner diameter of the second side hole 42, or the outer diameter of the microguide wire 3 is smaller than the inner diameter of the second side hole 42.

[0061] During use, if it is necessary to pre - dilate the stenosis 11 in the cerebral artery 1, first insert the micro - guide wire 3 into the interior of the micro - catheter 4 through the second side - hole 42, and then let the micro - guide wire 3 penetrate out from the front end of the micro - catheter 4; further, pass the micro - guide wire 3 through the stenosis 11 of the cerebral artery 1; further, under the guidance of the micro - guide wire 3, pass the micro - catheter 4 through the stenosis 11 until the balloon 5 is located at the stenosis 11 of the cerebral artery 1; further, fill the balloon 5 with a medium so that the balloon 5 can expand, thereby pre - dilating the stenosis 11; after the pre - dilation is completed, extract the medium in the balloon 5 to make the balloon 5 return to its original state, and then move the OCT probe 7 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, then move the balloon 5 to the stenosis 11 of the cerebral artery 1 again 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 micro - catheter assembly proposed in this application, both the balloon and the OCT probe are arranged on the micro - catheter. During use, there is no need to frequently extract or insert the balloon or the OCT probe from the cerebral artery, and only a small distance (a dozen or dozens of millimeters) of movement of the balloon or the OCT probe in the cerebral artery is required. Compared with the prior art, its operation difficulty is small and the operation time is short, which can not only reduce the risk of damage to the inner wall of the patient's cerebral artery, but also reduce other risks borne by the patient during the operation.

[0063] In this embodiment, without affecting the OCT probe 7, the second side - hole 42 can be at any suitable position on the micro - catheter 4. In an embodiment of the present application, the second side - hole 42 can be close to the front end of the micro - catheter 4. It should be noted that if the second side - hole 42 is too close to the front end of the micro - catheter 4, that is, the length of the solid part (hereinafter referred to as the first part) between the second side - hole 42 and the front end of the micro - catheter 4 (that is, the distance S1 as shown in Figure 4 is short, then during the process of the micro - guide wire 3 passing through the second side - hole 42, due to the short length of the first part, that is, the strength of the first part along the axial direction of the micro - catheter 4 is poor, so the micro - guide wire 3 is likely to cause the first part to rupture. If the first part of the micro - catheter 4 ruptures, then the micro - guide wire 3 must be detached from the micro - catheter 4. If the micro - guide wire 3 is detached from the micro - catheter 4, then the micro - guide wire 3 cannot guide the micro - catheter 4, that is, the front end of the micro - catheter 4 cannot move forward smoothly in the cerebral artery 1. In order to avoid the rupture of the first part of the micro - catheter 4 during use, in the embodiment of the present application, the second side - hole 42 being close to the front end of the micro - catheter 4 can refer to the straight - line distance between the axis line of the second side - hole 42 and the front - end face of the micro - catheter 4 (that is, as shown in 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 can also be any distance between two adjacent above distances.

[0064] In this embodiment, since the OCT probe 7 is a mature technology, it will not be elaborated here. It should be noted that since the OCT probe 7 is relatively precise, if the OCT probe 7 is relatively close to the second side hole 42, during the process of the micro-guide wire 3 passing through the second side hole 42, it is easy to damage the OCT probe 7. 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 line of the second side hole 42 (that is, as Figure 4 shown by the distance S2, 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 can also be any distance between two adjacent above distances.

[0065] It should be noted that only when the length of the OCT probe 7 is greater than the length of the stenosis 11 can the OCT probe 7 perform a complete scan of 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 arranged on the microcatheter 4, the strength of the part of the microcatheter 4 located at the OCT probe 7 is also worse, and thus it is easier to break. In order to enable the OCT probe 7 to be applicable to the scan of most stenoses 11 in the cerebral artery 1 and to avoid the microcatheter 4 from breaking during use, in an embodiment of the present application, the length of the OCT probe 7 (that is, as Figure 4 shown by the length S3) 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 can also be any length between two adjacent above lengths.

[0066] In the embodiment of the present application, as Figure 4 or Figure 5 shown, the balloon 5 and the microcatheter 4 can be of an integral structure. The balloon 5 and the OCT probe 7 are sequentially arranged on the microcatheter 4, and among 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 easily damaging the inner wall of the end of the cerebral artery 1 or easily 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, Figure 9 or Figure 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 move along the microcatheter 4 through the push catheter 6, as long as the microcatheter 4 can successfully pass through the stenosis 11 of the cerebral artery 1, the balloon 5 can also successfully pass through the stenosis 11 of the cerebral artery 1, and thus 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 applied to the application scenario where 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 capable of applying a pushing force to the balloon 5, so the push catheter 6 needs to have a certain rigidity. If the rigidity of the push catheter 6 is too strong, during the pushing process, the push catheter 6 is likely to damage the blood vessel wall of the cerebral artery 1. 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 material, polyurethane material or polytetrafluoroethylene material, etc.

[0073] In the embodiment of the present application, there are no restrictions on the shape and structure of the balloon 5, as long as the balloon 5 can move along the microcatheter 4 under the pushing and pulling 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] Embodiment 1 of the balloon

[0075] In this embodiment, the balloon 5 can be as shown in Figure 9 It can be an integrally formed sac with a 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 the balloon 5 reaches the stenosis 11, it needs to expand, that is, the balloon 5 itself also needs to have good flexibility.

[0076] Embodiment 2 of the balloon

[0077] If the balloon 5 is an integrally formed sac with a uniform wall thickness, then the balloon 5 either has insufficient rigidity or insufficient flexibility, that is, the use effect of the balloon 5 is not good. 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. Among them, as shown in Figure 10 The carrier 52 has a tubular structure. The film 53 is disposed outside the carrier 52, and a sealed cavity 51 is formed between the carrier 52 and the film 53.

[0078] During use, the carrier 52 is mainly used to provide rigidity so that the balloon 5 can move along the microcatheter 4 under the pushing action of the pusher catheter 6. The film 53 is mainly used to provide flexibility so that after the balloon 5 reaches the stenosis 11, a medium is filled into the closed cavity 51, and the film 53 can expand, thereby pre-expanding the stenosis 11. In this embodiment, through the settings of the carrier 52 and the film 53, the balloon 5 has a good use effect. It should be noted that in this embodiment, the relatively high rigidity of the carrier 52 means that the rigidity of the carrier 52 is greater than that of the film 53. Since the carrier 52 needs to pass through blood vessels during use, the carrier 52 also needs to be able to bend appropriately to adapt to the bending changes of the blood vessels.

[0079] In this embodiment, the carrier 52 can be made of the same material as the film 53. If the carrier 52 and the film 53 are made of the same material, the thickness of the carrier 52 in the radial direction of the balloon 5 can be significantly greater than the thickness of the film 53, so that the carrier 52 has good rigidity while the film 53 can have good flexibility.

[0080] In the embodiments of the present application, no restrictions are imposed on the shape and structure of the carrier 52. For example, the carrier 52 can be in a circular tubular shape (for example, only including the carrier tube 521 as shown in Figure 11 ), or the carrier 52 can be as shown in Figure 11 and include the carrier tube 521. Guide portions 522 are provided at both ends of the carrier tube 521, and the outer diameter of the guide portion 522 decreases in a first direction. The first direction is parallel to the axial direction of the carrier tube 521 and points from the guide portion 522 to the carrier tube 521.

[0081] It should be clear that since the outer diameter of each guide portion 522 decreases in the first direction, the first direction is parallel to the axial direction of the carrier tube 521, and the first direction points from the guide portion 522 to the carrier tube 521. That is to say, during the movement of the carrier 52 in the cerebral artery 1, since the outer diameters of the front end and the rear end of the carrier 52 are both small and the outer diameter decreases, the carrier 52 is easy to move in the cerebral artery 1, and the front end or the rear end of the carrier 52 is not likely 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 rely on the film 53. After the film 53 changes from the expanded state to the contracted state, wrinkles or protrusions are likely to form on its surface. If these wrinkles or protrusions rub against the inner wall of the cerebral artery 1, it is easy to damage the inner wall of the cerebral artery 1. In order that during the movement of the balloon 5, the film 53 does not rub against the inner wall of the cerebral artery 1, that is, the film 53 is not likely to damage the inner wall of the cerebral artery 1, in this embodiment, as shown in Figure 11As shown, the maximum outer diameter of the guiding part 522 can be greater than the outer diameter of the bearing tube 521, that is, an installation groove 523 can be formed between the bearing tube 521 and the two guiding parts 522. During use, the film 53 can be arranged between the two guiding parts 522, that is, the film 53 is arranged in the installation groove 523. Since the film 53 is located in the installation groove 523, during the movement of the balloon 5, the film 53 will not form friction with the inner wall of the cerebral artery 1. If the film 53 does not form friction with the inner wall of the cerebral artery 1, then the film 53 must not be likely to damage the inner wall of the cerebral artery 1.

[0083] In the embodiment of the present application, as Figure 10 shown, the film 53 can be a film with excellent elasticity. When the medium is filled into the closed cavity 51, the film 53 can expand, and then pre-expand the stenosis 11. As Figure 12 shown, the film 53 can also be a film with poor elasticity. During production, the film 53 can be stacked and arranged in the installation groove 523. When the medium is filled into the closed cavity 51, the film 53 can also expand, and then pre-expand 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 installation groove 523 under the action of its own elasticity. That is, the film 53 with excellent elasticity can still maintain a state of not forming friction with the inner wall of the cerebral artery 1 after the pre-expansion is completed, that is, the film 53 with excellent elasticity is not likely to damage the inner wall of the cerebral artery 1. If the elasticity of the film 53 is poor and it is arranged in the installation 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 completely retract into the installation groove 523. If the film 53 produces wrinkles or protrusions, these wrinkles or protrusions may protrude outside the installation groove 523, and then form friction with the inner wall of the cerebral artery 1, that is, it may damage the inner wall of the cerebral artery 1.

[0085] In order to ensure that regardless of the quality of the elasticity of the film 53, after the medium in the closed cavity 51 is extracted, the film 53 can completely and smoothly retract into the installation groove 523. In an embodiment of the present application, as Figure 16 shown, multiple micro-titanium alloy wires 532 can be arranged inside the film 53 (that is, such as Figure 16 or such as Figure 17 shown red silk threads). Each micro-titanium alloy wire 532 is used for if the current state of the film 53 (for example, such as Figure 14 and Figure 15 shown use state) and the initial state (that is, such as Figure 16If it is different from the usage state shown, each micro-titanium alloy wire 532 forms elastic potential energy, and the elastic potential energy is used to make the film 53 tend to change from the current state to the initial state.

[0086] In this embodiment, it can be as Figure 16 shown that each micro-titanium alloy wire 532 is in a ring shape with the head and tail connected, and the folding form of the micro-titanium alloy wire 532 is the same as the stacked form of the film 53. That is to say, if the film 53 is propped up by an external force, when the external force is removed, the film 53 can return to the initial state under the action of the elastic force formed by the micro-titanium alloy wire 532, that is, it can return to the initial stacked form as Figure 16 shown. In this embodiment, it can also be as Figure 17 shown that the micro-titanium alloy wire 532 is arranged at the stacked turning point of the film 53, and the micro-titanium alloy wire 532 makes the stacked films of adjacent two layers have a tendency to converge and approach. That is to say, if the film 53 is propped up by an external force, when the external force is removed, the two films at the stacked turning point of the film 53 will converge and approach under the action of the elastic force of the micro-titanium alloy wire 532, and finally can return to the initial state, that is, it can return to the initial stacked form as Figure 17 shown.

[0087] It should be noted that in the embodiment of the present application, only the stacked state of the film 53 as Figure 16 and Figure 17 shown is used to illustrate the initial state of the film 53 of the present application, which does not mean that the film 53 in the embodiment of the present application can only be stacked according to the stacked state as Figure 16 or Figure 17 shown. 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 with different stacked states.

[0088] It should be clear that as Figure 1 shown, in the application scenario where the abnormal mass 2 in the cerebral artery 1 is large in size while the size of the stenosis 11 is small, if the balloon 5 is used to expand the size of the stenosis 11 to the place at one time, it is easy to cause the rupture of the cerebral artery 1, and then cause a medical accident. In order to avoid the occurrence of this medical accident, if the size of the stenosis 11 is small, generally a balloon 5 with a smaller size after inflation (hereinafter referred to as the first balloon) needs to be used to perform the first pre-dilation on the stenosis 11 first, and then a balloon 5 with a larger size after inflation (hereinafter referred to as the second balloon) is used to perform the second pre-dilation on the stenosis 11.

[0089] In the prior art, the operation steps for performing two pre-dilatations on the stenosis 11 are as follows: First, under the guidance of the micro-guide wire 3, the micro-catheter 4 carrying the first balloon is passed through the stenosis 11, then the first balloon is moved to the stenosis 11, and then the first balloon is inflated so that the first balloon can perform the first pre-dilatation 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-guide wire 3, the micro-catheter 4 carrying the second balloon is passed through the stenosis 11, then the second balloon is moved to the stenosis 11, and then the second balloon is inflated so that the second balloon can perform the second pre-dilatation on the stenosis 11.

[0090] It should be clear that the operation steps for performing two pre-dilatations on the stenosis 11 in the prior art are relatively cumbersome, resulting in a long operation time and a large operation difficulty. It is easy to understand that the longer the operation time, the greater the risk borne by the patient, and the risk of damage to the inner wall of the cerebral artery 1 due to the operation of repeatedly withdrawing and inserting the micro-catheter 4 is also correspondingly increased. In order to reduce the above risks, in an embodiment of the present application, as Figure 12 shown, the thin film 53 can be laminated to form a plurality of laminated portions. As Figure 13 shown, each laminated portion at least includes a first laminated film 533 and a second laminated film 534. The first laminated film 533 and the second laminated film 534 are any two adjacent films in the corresponding laminated portion. A plurality of connecting micro-columns 531 are formed between the first laminated film 533 and the second laminated film 534, and the respective connecting micro-columns 531 are arranged in an array along the axial direction of the carrier 52. One end of each connecting micro-column 531 is connected to the first laminated film 533, and the other end of each connecting micro-column 531 is connected to the second laminated film 534. The breaking stress of the connecting micro-column 531 is less than the cracking stress of the thin film 53.

[0091] During use, the micro-catheter 4 can be passed through the stenosis 11 under the guidance of the micro-guide wire 3; then, under the guidance of the micro-catheter 4, the balloon 5 carrying the above-mentioned thin film 53 is moved to the stenosis 11 through the push catheter 6; further, a medium with a pressure less than the breaking stress of the connecting micro-column 531 is injected into the closed cavity 51 through the push catheter 6, then the thin film 53 as Figure 12 shown can be inflated, and the inflated thin film 53 as Figure 14 shown can perform the first pre-dilatation on the stenosis 11. After the first pre-dilatation is completed, a medium with a pressure greater than the breaking stress of the connecting micro-column 531 and less than the cracking stress of the thin film 53 is then injected into the closed cavity 51 through the push catheter 6, and the thin film 53 can be further inflated, and the inflated thin film 53 as Figure 15As shown, the second pre - dilation of the stenosis 11 can be carried out. That is to say, in this embodiment, through a single balloon 5, the two pre - dilations with different size requirements for the stenosis 11 can be achieved. Compared with the prior art, the operation is simple, without the need to insert the micro - catheter 4 into the cerebral artery multiple times, and it can greatly save the time for pre - dilating the stenosis 11, that is, reduce the risk borne by the patient during the operation.

[0092] In another embodiment of the present application, as Figure 18 shown, one end of each connecting micro - column 531 can be connected to the thin film 53; the other end of each connecting micro - column 531 can be connected to the carrier 52 (that is, the carrier tube 521). During use, by pushing the catheter 6 to inject a medium with a pressure less than the breaking stress of the connecting micro - column 531 into the sealed cavity 51, then as Figure 12 shown, the thin film 53 can be inflated. After inflation, the thin film 53 as Figure 19 shown can carry out the first pre - dilation of the stenosis 11. After the first pre - dilation is completed, then by pushing the catheter 6 to inject a medium with a pressure greater than the breaking stress of the connecting micro - column 531 and less than the cracking stress of the thin film 53 into the sealed cavity 51, the thin film 53 can be further inflated. After inflation, the thin film 53 as Figure 15 shown can carry out the second pre - dilation of the stenosis 11.

[0093] It should be noted that as Figure 3 shown, when the micro - catheter assembly in the prior art dilates the stenosis 11 of the cerebral artery 1, the balloon 5 will block the entire cerebral artery 1. If the operation time is relatively long, it will cause insufficient blood supply to the patient's brain or other organs such as the head. Seriously, 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 micro - catheter assembly further includes a micro - guide wire 3 and a micro - catheter 4. As Figure 12 shown, the outer diameter of the micro - catheter 4 (that is, the outer diameter d as Figure 12 shown) is smaller than the inner diameter of the carrier 52 (that is, the inner diameter D as Figure 12 shown). As can be seen from the foregoing, since the carrier 52 has a certain rigidity, when the medium is filled into the sealed cavity 51, the inner wall of the carrier 52 and the outer wall of the micro - catheter 4 will not be completely adhered. If the inner wall of the carrier 52 and the outer wall of the micro - catheter 4 are not completely adhered, the blood in the cerebral artery 1 can freely flow through the gap between the carrier 52 and the micro - catheter 4. That is to say, it can effectively avoid the phenomenon that when dilating the stenosis 11 of the cerebral artery 1, due to the complete blockage of the cerebral artery 1, the blood supply to the patient's brain or other organs such as the head is insufficient.

[0094] As described above, the microcatheter assembly proposed in this 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 (i.e., 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 will be relatively close to the stenosis 11 during use. If the front end of the microcatheter 4 is relatively close to the stenosis 11, there is a risk of the balloon 5 detaching from the microcatheter 4 when the balloon 5 is moved by pushing the catheter 6. As described above, the microcatheter 4 is mainly used to guide the movement of the balloon 5. If the balloon 5 detaches from the microcatheter 4, it is difficult to remove the balloon 5 from the cerebral artery 1 without damaging the cerebral artery 1. To avoid the balloon 5 detaching from the microcatheter 4 during use, in an embodiment of this application, the microcatheter 4 can also be provided with a limiting ring 41, as Figure 7 and Figure 8 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 (i.e., the inner diameter D as Figure 12 shown).

[0095] It should be noted that in this embodiment, since the outer diameter of the limiting ring 41 is greater than the inner diameter of the balloon 5, the balloon 5 cannot detach from the microcatheter 4 at the front end of the microcatheter 4 under the limiting action of the limiting ring 41. In this embodiment, the limiting ring 41 being close to the front end of the microcatheter 4 means that 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 H as Figure 8 shown) is less than or equal to 2 mm. Of course, in other embodiments of this application, the distance between the front end face of the limiting ring 41 and the front end face of the microcatheter 4 can also be greater than 2 mm, for example: 4 mm or 5 mm, etc., and no limitation is made here.

[0096] In the embodiment of this application, the limiting ring 41 can be any ring that can limit the movement of the balloon 5. For example, the limiting ring 41 can be a ring with a square cross-section, where the cross-section is a section parallel to the axis of the limiting ring 41; the limiting ring 41 can also be as Figure 7 and Figure 8 shown, with a semi-circular cross-section. It is easy to understand that if the cross-section of the limiting ring 41 is semi-circular, it is not easy to damage the inner wall of the cerebral artery 1 when the limiting ring 41 moves in the cerebral artery 1.

[0097] In the embodiment proposed in this application, through the settings of the first connecting pipe, the corrugated pipe, the second connecting pipe, and the control microfilament, the operator can accurately adjust the spatial angle of the front end of the microcatheter through the control microfilament, so that the spatial angle of the front end of the microcatheter can be similar to the spatial angle of the bend at the stenosis, thereby making it easy for the microcatheter to pass through the stenosis with various different bend spatial angles.

[0098] Although embodiments of the present application have been shown and described, those of ordinary skill in the art will understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present application. The scope of the present application is defined by the appended claims and their equivalents.

Claims

1. A microcatheter assembly, characterized in that, Comprising: A microcatheter (4); the microcatheter (4) includes a first connecting tube (43), a corrugated tube (44), and a second connecting tube (45) connected in sequence; A balloon (5) disposed on the first connecting tube (43); At least one control microfilament (8); the first connecting tube (43) is further provided with first side holes (46) corresponding one-to-one to the control microfilaments (8); the front ends of the respective control microfilaments (8) pass through the corresponding first side holes (46) and are connected to the inner wall of the second connecting tube (45); The first connecting tube (43) is further 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 includes: A microguide wire (3); the microguide wire (3) is adapted to the second side hole (42); An OCT probe (7) disposed on the first connecting tube (43); The balloon (5) and the microcatheter (4) are of an integral structure; the balloon (5) and the OCT probe (7) are sequentially disposed on the microcatheter (4), and among the balloon (5) and the OCT probe (7), the OCT probe (7) is closer to the front end of the microcatheter (4); The balloon (5) is of a tubular structure, and the balloon (5) can be movably sleeved outside the microcatheter (4); a sealed cavity (51) is formed inside the balloon (5); the microcatheter assembly further includes a push catheter (6), and the push catheter (6) is connected to the rear end of the balloon (5); the push catheter (6) is communicated with the sealed cavity (51); The balloon (5) includes: A carrier (52); the carrier (52) is of a tubular structure; A thin film (53) disposed outside the carrier (52); the sealed cavity (51) is formed between the carrier (52) and the thin film (53); The carrier (52) includes a carrier tube (521); both ends of the carrier tube (521) are provided with guiding parts (522); the outer diameter of the guiding parts (522) decreases in a first direction; the first direction is parallel to the axial direction of the carrier tube (521) and points from the guiding parts (522) to the carrier tube (521).

2. The microcatheter assembly according to claim 1, wherein The maximum outer diameter of the guiding part (522) is greater than the outer diameter of the carrier tube (521); an installation groove (523) is formed between the carrier tube (521) and the two guiding parts (522); the thin film (53) is stacked in the installation groove (523).

3. The microcatheter assembly according to claim 2, wherein, Multiple micro-titanium alloy wires (532) are arranged inside the thin film (53); when the current state of the thin film (53) is different from the initial state, elastic potential energy is formed in the respective micro-titanium alloy wires (532), and the elastic potential energy is used to make the thin film (53) tend to change from the current state to the initial state.

4. The microcatheter assembly according to claim 3, wherein The thin film (53) is formed with a plurality of stacked portions; 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-columns (531) are provided between each stacked portion and the carrier (52), and the respective connecting micro-columns (531) are arrayed along the axial direction of the carrier (52); the fracture stress of the connecting micro-columns (531) is less than the cracking stress of the thin film (53); one end of each connecting micro-column (531) is connected to the first stacked film (533), and the other end of each connecting micro-column (531) is connected to the second stacked film (534); or, one end of each connecting micro-column (531) is connected to the thin film (53), and the other end of each connecting micro-column (531) is connected to the carrier (52).

5. The microcatheter assembly according to any one of claims 1 to 4, characterized in that, The outer diameter of the microcatheter (4) is smaller than the inner diameter of the carrier (52); the microcatheter (4) is further provided with a limiting ring (41), and the limiting ring (41) is close to the front end of the microcatheter (4); the maximum outer diameter of the limiting ring (41) is larger than the inner diameter of the carrier (52).

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