Steerable balloon occlusion microcatheter

Abstract

A steerable balloon occlusion microcatheter, which relates to the technical field of interventional catheters. The steerable balloon occlusion microcatheter comprises an integral balloon structure (231) and a steerable structure (1). The integral balloon (231) and a catheter outer layer (23) are integrally formed and are not bonded or welded to a catheter body (2), which can increase the strength of the balloon (231) and reduce the risks of using in high-pressure environments. The steerable structure (1) enables bending control of the distal end of the catheter body (2), which can improve the efficiency of the catheter passing through the human body lumen, thereby improving the success rate of surgery and the treatment precision, and reducing the risk of surgery and a waste caused by device failure.

Description

A controllable curved balloon occlusion microcatheter Technical Field

[0001] This invention relates to the field of interventional catheter technology, and in particular to a controllable curved balloon occlusion microcatheter. Background Technology

[0002] Interventional catheters are indispensable tools in procedures involving bifurcated vessels and requiring precise localization, such as diaphragmatic puncture, cardiovascular intervention, peripheral vascular intervention, atrial septal puncture, renal artery ablation, heart valve repair, and tumor embolization. Pre-shaped catheters are typically used to establish an external pathway to the target location, facilitating the entry of guidewires or other instruments for diagnosis and treatment. However, due to individual differences in human anatomy, pre-shaped catheters cannot perfectly adapt to all clinical needs. If an inserted catheter does not fit the patient's physiological structure, it must be withdrawn and a new catheter inserted, increasing procedure time and potentially causing harm to the patient.

[0003] To accommodate individual differences in human physiological and anatomical structures, controllable bending catheters have emerged and gained widespread application. A controllable bending catheter features a controllable bend at the distal end of the catheter body. By manipulating the catheter handle, the traction wire connected to the controllable bend moves axially, causing the distal end of the catheter to bend at different angles. When the bending angle of the controllable bend conforms to the specific physiological structural characteristics of the human lumen, the handle is stopped, and the distal end of the catheter is aligned with the target lumen inlet. Diagnostic and / or therapeutic instruments / media are then delivered into the target lumen through the catheter.

[0004] Interventional procedures such as tumor embolization, aneurysm embolization, and Marshall ablation typically employ balloon occlusion microcatheters. This involves infusing media and / or fluids and / or embolic materials and / or appropriate instruments (such as stents or coils) through the microcatheter, and temporarily occluding peripheral blood vessels or neurovascular structures by releasing the media from the distal end of the microcatheter via an inflatable balloon, or selectively blocking or controlling blood flow. Balloon occlusion microcatheters are a type of interventional catheter with a very small diameter. While there is no strict size definition, small catheters with a diameter of 0.70-1.30 mm are often referred to as microcatheters. Microcatheters generally have a reinforced, multi-layered composite structure and are frequently used in interventional treatments involving minute blood vessels.

[0005] Traditional balloon occlusion microcatheters connect or attach the balloon to the microcatheter body via adhesive or welding. These methods not only increase the complexity of the fabrication process but also pose a risk of instability in the connection structure under high pressure or complex working conditions. Furthermore, due to the inherent precision of the microcatheter and the special structure with the balloon, achieving controllable bending of balloon occlusion microcatheters presents significant challenges in terms of structural rationality, strength, and manufacturing feasibility. Existing conventional balloon occlusion microcatheters cannot, like larger-scale controllable bending conventional catheters, adjust their distal ends to adapt to a suitable bending shape to pass through narrow and convoluted human lumens. Therefore, current operators face significant operational difficulties, require improved treatment precision, and are susceptible to surgical risks and equipment failure / destruction.

[0006] Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of existing technologies and provide a controllable bending balloon occlusion microcatheter, comprising an integral balloon structure and a controllable bending structure. The integral balloon is molded as a single unit with the outer layer of the catheter and is not bonded or welded to the catheter, which reduces the complexity of the balloon microcatheter manufacturing process and lowers the risks associated with balloon use under high pressure. The controllable bending structure allows for manipulation of the distal bending of the catheter, improving the efficiency of the catheter passing through the body's lumen, thereby increasing the success rate and treatment precision of the procedure, and reducing surgical risks and equipment failure / waste.

[0008] To achieve the above objectives, the present invention provides a controllable bending balloon occlusion microcatheter, comprising a catheter body and a controllable bending base. The catheter body has a multi-layer structure, including an inner layer, a middle layer, and an outer layer, all made of high molecular polymer material. The inner layer forms an infusion lumen, and an expansion lumen is formed between the middle layer and the outer layer. The proximal end of the catheter body is an inflexible section, and the distal end is a flexible section.

[0009] The outer layer of the catheter is equipped with an integral balloon. The outer layer of the catheter can be divided into a non-balloon proximal segment, a balloon segment, and a non-balloon distal segment. The balloon segment is an elastic, expandable balloon. The balloon is integrally formed with the outer layer of the catheter and is not glued or welded to the catheter. The balloon has a smooth surface and is completely attached to the middle layer of the catheter when it is not inflated.

[0010] The catheter intermediate layer has at least one traction wire inside, and a limiting sleeve is provided outside the traction wire. The traction wire is connected to the distal end of the catheter intermediate layer. The controllable bending base is provided with a drug infusion interface, a medium infusion interface and a traction and bending control mechanism. The controllable bending base controls the bendable section of the catheter body through the traction wire. The drug infusion interface is connected to the infusion lumen, and the medium infusion interface is connected to the expansion lumen.

[0011] In some embodiments, a metal reinforcing layer is provided between the inner layer of the catheter and the middle layer of the catheter. The metal reinforcing layer is configured as a metal braided tube, a metal spring tube, a metal thiopanthus tube, or a composite tube formed by connecting a metal spring tube and a thiopanthus tube in series.

[0012] In some embodiments, the inner layer of the catheter includes a metal braided layer and a polymer layer, wherein the metal braided layer and the polymer layer are combined to form an integrated composite structure.

[0013] In some embodiments, the polymer materials used for the inner layer, middle layer, outer layer and limiting sleeve of the catheter include one or more of Nylon, PEBAX, PEU, PTFE, PU, ​​PI or PEEK.

[0014] In some embodiments, when the balloon is in an uninflated state, the difference between the outer diameter of the balloon segment of the outer layer of the catheter and the outer diameter of the proximal and distal non-balloon segments is less than 0.1 mm.

[0015] In some embodiments, a positioning component is provided at the distal end of the catheter intermediate layer. The positioning component is annular and sleeved on the catheter intermediate layer. The positioning component is made of radiopaque material. Traction lines are evenly distributed circumferentially in the catheter intermediate layer. The traction lines are connected to the positioning component, and the connection points are evenly distributed along the positioning component. The connection method includes welding or wrapping.

[0016] In some embodiments, no positioning component is set at the distal end of the catheter intermediate layer, and the traction wires are evenly distributed circumferentially along the central axis of the catheter intermediate layer. The traction wires are fixedly connected to the distal end of the catheter intermediate layer by winding. In a further aspect, when multiple traction wires are fixedly connected to the distal end of the catheter intermediate layer by winding, different traction wires can control the flexible section of the catheter body to bend in different directions.

[0017] In some embodiments, the balloon is provided with a first radiopaque ring and a second radiopaque ring. The first radiopaque ring is located at the junction of the proximal non-balloon segment and the balloon segment of the outer layer of the catheter, and the second radiopaque ring is located at the junction of the balloon segment and the distal non-balloon segment of the outer layer of the catheter.

[0018] In some embodiments, the traction bending control mechanism includes a manual bending control component and a locking component. The manual bending control component drives the traction line to move so as to drive the bendable section of the conduit body to bend. The locking component has two states: locked and unlocked. When the locking component is in the locked state, it restricts the movement of the manual bending control component.

[0019] In some embodiments, the manual bending control component and the locking component are designed as operable mechanical structures, which may take the form of a wheel, a knob, or a slide.

[0020] In some embodiments, the outer layer of the catheter includes a plurality of non-adjacent balloon segments, each balloon segment being an elastic, inflatable balloon, and all balloons communicating with an inflatable lumen. In a further aspect, the plurality of balloons may be inflated simultaneously.

[0021] In some embodiments, both the drug infusion interface and the medium infusion interface are Luer connectors.

[0022] In some embodiments, the distal end of the catheter intermediate layer is provided with two non-adjacent positioning components, each positioned at a different part of the flexible section of the catheter body, and traction lines are respectively connected to the positioning components to control multiple bends of the catheter body.

[0023] Due to the application of the above technical solution, the present invention has the following beneficial effects compared with the prior art. On the one hand, the controllable bending balloon occlusion microcatheter adopts an integral balloon structure. The outer balloon section of the catheter is an elastic, expandable balloon. The balloon and the outer layer of the catheter are integrally formed without being glued or welded. In high-pressure environments, the integral balloon can exhibit good safety and stability. The integral formation of the balloon and the outer layer of the catheter also avoids the cumbersome process of traditional balloons requiring gluing or welding. On the other hand, the controllable bending balloon occlusion microcatheter adopts a controllable bending structure. By controlling the bending of the flexible section of the catheter, the efficiency of the catheter passing through the human body lumen is improved, the operation time and surgical risks are reduced, and thus the success rate and treatment accuracy are improved. Attached Figure Description

[0024] Figure 1 is a schematic diagram of an embodiment of the controllable curved balloon occlusion microcatheter proposed in this invention;

[0025] Figure 2 is a schematic diagram of an embodiment of the controllable curved balloon occlusion microcatheter proposed in this invention in the balloon inflated, distally bent and locked state.

[0026] Figure 3 is a cross-sectional view of the catheter body of an embodiment of the controllable curved balloon occlusion microcatheter proposed in this invention;

[0027] Figure 4 is a schematic diagram of the outer layer structure of a controllable curved balloon occlusion microcatheter proposed in this invention.

[0028] Figure 5 is a schematic diagram of the traction line, positioning component and limiting sleeve in the catheter body of an embodiment of the controllable curved balloon occlusion microcatheter proposed in this invention.

[0029] Figures 6A, 6B, and 6C are schematic diagrams of the bending control and locking principles of multiple embodiments of the controllable bending balloon occlusion microcatheter proposed in this invention.

[0030] Figure 7 is a schematic diagram of the structure of an embodiment of the controllable curved balloon occlusion microcatheter proposed in this invention, showing that the outer layer of the catheter contains multiple non-adjacent balloon segments.

[0031] Figure 8 is a schematic diagram of an embodiment of the controllable curved balloon occlusion microcatheter proposed in this invention, showing that the distal end of the catheter's intermediate layer has two positioning components.

[0032] Figures 9A, 9B, and 9C are schematic diagrams showing the structure of the traction line and the middle layer of the catheter being wound and connected in several embodiments of the controllable curved balloon occlusion microcatheter proposed in this invention.

[0033] List of feature names corresponding to the reference numerals in the figure: 1. Controllable bending base; 11. Drug / device infusion interface; 12. Medium infusion interface; 13. Traction bending control mechanism; 131. Manual bending control component; 132. Locking component; 2. Catheter body; 21. Inner layer of catheter; 22. Middle layer of catheter; 221. Traction line; 222. Positioning component; 223. First contrast ring; 224. Second contrast ring; 225. Limiting sleeve; 23. Outer layer of catheter; 231. Balloon / balloon segment; 232. Proximal non-balloon segment; 233. Distal non-balloon segment; 24. Metal reinforcement layer; 25. Infusion lumen; 26. Expandable lumen; 3. Flexible section of catheter body; 4. Inflexible section of catheter body. Detailed Implementation

[0034] The present invention will be further described in detail below with reference to specific embodiments and accompanying drawings. In the field of medical devices, the proximal end refers to the end of the medical device that is controlled by a doctor or outside the human body, and the distal end refers to the other end of the medical device that plays a diagnostic / therapeutic role or is inside the human body. The proximal and distal directions are defined accordingly, and the distal and proximal ends of the overall structure or individual parts are named accordingly for the convenience of detailed description.

[0035] This invention proposes a controllable curved balloon occlusion microcatheter for use in interventional procedures such as tumor interventional embolization, aneurysm embolization, and Marshall anhydrous alcohol ablation. By infusing media and / or liquids and / or embolization materials and / or appropriate instruments (such as stents and coils), it can temporarily occlude peripheral blood vessels or neurovascular vessels, or selectively block or control blood flow.

[0036] An embodiment of the controllable curved balloon occlusion microcatheter in this invention:

[0037] A controllable-bend balloon occlusion microcatheter includes a controllable-bend base 1 and a catheter body 2. The controllable-bend base 1 is provided with a drug-device infusion interface 11, a medium infusion interface 12, and a traction control mechanism 13. The distal end of the controllable-bend base 1 is connected to the proximal end of the catheter body 2. The catheter body includes an inner layer 21, a middle layer 22, and an outer layer 23 from the inside out. The inner layer 21 and the outer layer 23 are made of a soft polymer material. The inner layer 21 forms an infusion lumen 25, and the outer layer and the middle layer form an expansion lumen 26.

[0038] The catheter intermediate layer 22 includes a metal braided layer and a polymer layer, which are combined to form an integrated composite structure. A limiting sleeve 225 is located in the middle of the catheter intermediate layer 22, and a traction wire 221 is located inside the limiting sleeve 225. A positioning component 222 is located at the distal end of the catheter intermediate layer 22. The positioning component 222 is a circular annular component made of radiopaque material and is fitted onto the catheter intermediate layer 22. The distal end of the traction wire 221 is connected to the positioning component 222 by welding.

[0039] The outer layer 23 of the catheter is provided with an integral balloon 231. The outer layer 23 of the catheter can be divided into a non-balloon proximal segment 232, a balloon segment 231, and a non-balloon distal segment 233. The balloon segment 231 is an elastic, expandable balloon 231. The balloon 231 is integrally formed with the outer layer 23 of the catheter and is not glued or welded to the catheter body 2. The balloon 231 has a smooth surface. When the balloon 231 is not inflated, it is completely attached to the middle layer 22 of the catheter. The expansion lumen 26 is connected to the balloon 231 and the medium infusion interface 12. When the fluid medium reaches the balloon 231 through the expansion lumen 26 via the medium infusion interface 12, the balloon 231 is no longer attached to the middle layer 22 of the catheter, thus forming a circumferentially expanded state. It then adheres to the inner wall of the human body lumen to temporarily block peripheral blood vessels or neurovascular vessels. The filling and unloading control of the fluid medium is the control of blood flow blockage and flow.

[0040] When the balloon 231 is in an uninflated state, the outer diameter of the balloon segment 231 of the outer layer 23 of the catheter is equal to the outer diameter of the non-balloon proximal segment 232 and the non-balloon distal segment 233 of the outer layer 23 of the catheter.

[0041] The traction bending mechanism 13 includes a manual bending component 131 and a locking component 132. The manual bending component 131 is connected to the proximal end of the traction line 221. The manual bending component 131 drives the proximal end of the traction line 221 to move, thereby causing the traction line 221 to drive the bendable section 3 in the catheter body 2 to bend. When the traction line 221 is displaced, the length remaining in the catheter body 2 is shortened, and the positioning component 222 in the catheter body 2 bends toward the traction line 221, thereby causing the catheter body 2 to bend. When the locking component 132 is in the open state, the manual bending component 131 can move freely to change the displacement of the traction line 221. When the locking component 132 is in the locked state, the manual bending component 131 is restricted from moving, thereby restricting the displacement of the traction line 221.

[0042] Inside the balloon 231, there are a first radiopaque ring 223 and a second radiopaque ring 224, wherein the first radiopaque ring 223 and the second radiopaque ring 224 are disposed inside the intermediate layer 22 of the catheter; the first radiopaque ring 223 is located at the adjacent position between the non-balloon proximal segment 232 and the balloon segment 231 of the outer layer 23 of the catheter, and the second radiopaque ring 224 is located at the adjacent position between the balloon segment 231 and the non-balloon distal segment 233 of the outer layer 23 of the catheter.

[0043] In one specific embodiment, the metal braided layer inside the catheter intermediate layer 22 is a composite structure formed by connecting a metal spring tube and a metal thiopanthate tube in series; the polymer material of the catheter inner layer 21 can be selected from PTFE, PU, ​​PEBAX, PI, Nylon or PEEK; the polymer material of the polymer layer included in the catheter intermediate layer 22 can be selected from Nylon, PEBAX or PEU, and the material of the metal braided layer included in the catheter intermediate layer 22 can be selected from nickel-titanium, stainless steel or tungsten; the polymer material of the catheter outer layer 23 can be selected from HDPE, PTFE, PEBAX, PI, PU, ​​silicone rubber or PEU; the material used for the limiting sleeve 225 can be selected from PTFE or UHMW-PE.

[0044] In one specific embodiment, the intermediate layer 22 of the catheter is provided with two limiting sleeves 225, which are symmetrically distributed in the intermediate layer 22. Each limiting sleeve 225 contains two traction wires 221, which are respectively connected to a ring-shaped positioning component 222 by welding, with the connection points symmetrically distributed. The manual bending control component 131 can independently manipulate the two traction wires 221 to achieve bending of the flexible section of the catheter body 2 in different directions.

[0045] In one specific embodiment, the distal end of the catheter intermediate layer 22 is provided with two non-adjacent positioning components 222, and the catheter intermediate layer 22 is provided with two limiting sleeves 225. The two limiting sleeves 225 are symmetrically distributed in the catheter intermediate layer 22, and there are two traction lines 221 inside the two limiting sleeves 225 respectively. The two traction lines 221 are respectively connected to the two positioning components 222. The traction bending mechanism 13 can independently operate the two traction lines 221 to realize the bending of multiple bendable sections of the catheter body 2 at the same time.

[0046] In one specific embodiment, the outer layer 2 of the catheter is provided with multiple non-adjacent balloon segments 231, that is, multiple balloon segments 231 are connected in series with multiple non-balloon segments to form an integrally formed outer layer 2 of the catheter; each balloon segment 231 is an elastic, expandable balloon 231, and multiple balloons 231 are connected to the expansion lumen 26. When the fluid medium reaches the multiple balloons 231 through the medium infusion interface 12 via the expansion lumen 26, the multiple balloons 231 no longer adhere to the middle layer 22 of the catheter, thus forming a circumferentially expanded state, and then adhering to the inner wall of multiple segments of the human body lumen to achieve precise occlusion of specific lumen segments.

[0047] In some specific embodiments, in order to avoid the impact on manufacturing difficulty, structural strength and balloon shape performance caused by the positioning component 222 being located in the section where the balloon 231 is located, preferably, the positioning component 222 is located in the non-balloon distal segment 233 of the outer layer 23 of the catheter.

[0048] In some specific embodiments, both the drug infusion interface 11 and the medium infusion interface 12 are Luer connectors to ensure a uniform standard for easy connection.

[0049] In the description of the embodiments of the present invention, terms such as "upper," "lower," "bottom," "inner," and "outer" that describe direction and positional relationships are used only for the convenience of describing the present invention and should not be construed as limiting the present invention.

[0050] In the relevant descriptions of this application, unless otherwise expressly stated, terms such as “connection” and “linked” should be interpreted broadly, including but not limited to fixed connection, detachable connection, integral connection, indirect connection through a medium, or mechanical connection, electrical connection, or connection of conductive components.

[0051] The embodiments of this invention are only for illustrating the technical concept and features of this invention, and are intended to enable those skilled in the art to understand the content of this invention and implement it. They should not be used to limit the scope of protection of this invention. All equivalent changes or modifications made in accordance with the spirit and essence of this invention should be covered within the scope of protection of this invention.

Claims

1. A controllable curved balloon occlusion microcatheter, characterized in that, Includes the catheter body and the controllable bending base; The catheter body includes an inner layer, a middle layer, and an outer layer. The inner layer, the middle layer, and the outer layer are made of a high molecular polymer material. The inner layer forms an infusion lumen, and the middle layer and the outer layer form an expansion lumen. The proximal end of the catheter body is an inflexible section, and the distal end of the catheter body is a flexible section. The outer layer of the catheter is provided with an integral balloon, which can be divided into a non-balloon proximal section, a balloon section and a non-balloon distal section. The balloon section is an elastic, expandable balloon, wherein the balloon is integrally formed with the outer layer of the catheter, the balloon has a smooth surface, and the balloon is completely attached to the middle layer of the catheter when it is not inflated. At least one traction wire is provided inside the intermediate layer of the catheter, and a limiting sleeve is provided outside the traction wire. The traction wire is connected to the distal end of the intermediate layer of the catheter. The controllable bending base is provided with a drug infusion interface, a medium infusion interface and a traction bending mechanism. The controllable bending base controls the bendable section of the catheter body via the traction line. The drug infusion interface is connected to the infusion lumen and the medium infusion interface is connected to the expansion lumen.

2. The controllable curved balloon occlusion microcatheter according to claim 1, characterized in that, A metal reinforcing layer is provided between the inner layer of the catheter and the middle layer of the catheter. The metal reinforcing layer is configured as a metal braided tube, a metal spring tube, a metal thiopanthate tube, or a composite tube formed by connecting a spring tube and a thiopanthate tube in series.

3. The controllable curved balloon occlusion microcatheter according to claim 1, characterized in that, The inner layer of the catheter includes a metal braided layer and a polymer layer, which are combined to form an integrated composite structure.

4. The controllable curved balloon occlusion microcatheter according to claim 2 or 3, characterized in that, The inner layer of the catheter, the middle layer of the catheter, the outer layer of the catheter, and the limiting sleeve are made of one or more of the following polymer materials: Nylon, PEBAX, PEU, PTFE, PU, ​​PI, or PEEK.

5. The controllable curved balloon occlusion microcatheter according to claim 4, characterized in that, When the balloon is in an uninflated state, the difference between the outer diameter of the balloon segment of the outer layer of the catheter and the outer diameter of the proximal and distal non-balloon segments is less than 0.5 mm.

6. The controllable curved balloon occlusion microcatheter according to claim 5, characterized in that, The distal end of the intermediate layer of the catheter is provided with a positioning component. The positioning component is circular in shape and is sleeved on the intermediate layer of the catheter. The positioning component is made of radiopaque material. The traction wires are evenly distributed circumferentially in the intermediate layer of the catheter. The traction wires are connected to the positioning component and the connection points are evenly distributed along the positioning component. The connection method includes welding or wrapping.

7. The controllable curved balloon occlusion microcatheter according to claim 5, characterized in that, No positioning component is set at the distal end of the intermediate layer of the catheter. The traction wires are evenly distributed circumferentially along the central axis of the intermediate layer of the catheter, and the distal end of the traction wires is fixedly connected to the intermediate layer of the catheter by winding.

8. The controllable curved balloon occlusion microcatheter according to claim 6 or 7, characterized in that, The balloon is provided with a first radiopaque ring and a second radiopaque ring. The first radiopaque ring is located at the junction of the proximal non-balloon segment and the balloon segment on the outer layer of the catheter, and the second radiopaque ring is located at the junction of the balloon segment and the distal non-balloon segment on the outer layer of the catheter.

9. The controllable curved balloon occlusion microcatheter according to any one of claims 1-8, characterized in that, The traction bending control mechanism includes a manual bending control component and a locking component. The manual bending control component drives the traction line to move so as to drive the bendable section of the conduit body to bend. The locking component has two states: locked and unlocked. When the locking component is in the locked state, it restricts the movement of the manual bending control component.

10. The controllable curved balloon occlusion microcatheter according to claim 9, characterized in that, The manual bending control component and the locking component are designed as operable mechanical structures, which may employ a wheel, knob, or slide.

11. The controllable curved balloon occlusion microcatheter according to claim 9, characterized in that, The outer layer of the catheter includes multiple non-adjacent balloon segments, each of which is an elastic, expandable balloon, and each balloon is connected to the expandable lumen.

12. The controllable curved balloon occlusion microcatheter according to claim 9, characterized in that, Both the drug infusion interface and the medium infusion interface are Luer connectors.

13. The controllable curved balloon occlusion microcatheter according to claim 6, characterized in that, The distal end of the intermediate layer of the catheter is provided with two non-adjacent positioning components. Each positioning component is located at a different position in the flexible section of the catheter body. The traction line is connected to the positioning component to control multiple bends of the catheter body.

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