Intracranial low-pressure drug-coated balloon dilatation catheter

Abstract

The invention discloses an intracranial low-pressure drug-coated balloon dilatation catheter, which belongs to the technical field of medical instruments, and comprises a balloon dilatation catheter assembly, a balloon dilatation catheter, a balloon dilatation catheter and a balloon dilatation catheter, the sacculus part is fixed on the peripheral outer wall of one end, close to the guide end tube, of the outer tube, and the peripheral outer wall of the sacculus part is provided with a medicine part; the medicine coating wrapping protection assembly comprises an elastic wrapping expansion body wrapping the peripheral side of the balloon piece in a totally-closed mode; wherein the balloon part extrudes the elastic wrapping expansion body after being inflated and expanded, so that the elastic wrapping expansion body is synchronously and elastically expanded and then opens and exposes the medicine part, the medicine part is laid on the blood vessel wall of an affected part, and the elastic wrapping expansion body comprises two half elastic expansion bodies which are symmetrically arranged. The drug parts on the surface of the balloon part are protected and prevented from being washed away by blood or released in advance before reaching the target position, and the integrity and activity of the drug parts in the conveying process are effectively protected.

Description

Technical Field

[0001] The invention belongs to the technical field of medical devices, in particular to an intracranial hypotension drug-coated balloon dilatation catheter. Background Art

[0002] Intracranial vascular stenosis or occlusion is one of the main causes of serious neurological diseases such as stroke. Traditional treatments include drug therapy, surgery and interventional therapy, among which balloon dilatation is a commonly used interventional therapy. By sending a balloon catheter into the lesion and inflating it, the narrowed blood vessels can be effectively dilated and blood flow can be restored. However, existing balloon dilatation catheters have some problems and limitations in practical applications, which limit their therapeutic effects and patient safety.

[0003] Traditional balloon dilatation catheters usually do not have a drug protection structure, making it difficult to ensure that the drug is evenly distributed in the lesion site, resulting in the drug being washed away by the blood during delivery. Premature release or loss of the drug may cause the local drug concentration to be too high or too low, affecting the treatment effect. Summary of the invention

[0004] The purpose of the present invention is to provide an intracranial hypotension drug-coated balloon dilatation catheter to solve the problems raised in the background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: an intracranial hypotension drug-coated balloon dilatation catheter, comprising:

[0006] The balloon dilatation catheter assembly comprises an outer tube and a guide end tube connected to one end of the outer tube;

[0007] A balloon component is fixed on the peripheral outer wall of the outer tube near one end of the guide end tube, and the peripheral outer wall of the balloon component has a medicine component;

[0008] The drug coating and protection component includes an elastically wrapped expansion body that is fully enclosed and wrapped around the circumference of the balloon component;

[0009] When the balloon is inflated, it squeezes the elastically wrapped expansion body, so that the elastically wrapped expansion body is elastically expanded synchronously and then opens to expose the medicine piece, and the medicine piece is applied to the blood vessel wall of the affected area.

[0010] Preferably, the elastically wrapped expansion body comprises two symmetrically arranged halves of the elastic expansion body, and the two halves of the elastic expansion body are sealed and connected together at opposite ends by a first tearable point line;

[0011] The two halves of the elastic expansion bodies are arranged to be rolled back and away from each other on the circumference of the balloon component.

[0012] Preferably, in this solution, the balloon member comprises a first side end expansion portion and a second side end expansion portion, and opposite ends of the two halves of the elastic expansion bodies are fixedly wrapped around the peripheral outer walls of the first side end expansion portion and the second side end expansion portion respectively.

[0013] In this solution, preferably, a plurality of medicine grooves are provided in an annular array on the outer wall of the circumference of the balloon member between the first side end expansion portion and the second side end expansion portion;

[0014] A portion of the medicine pieces are stored and accumulated in the medicine trough;

[0015] Another part of the drug component is coated on the first side end expansion portion, the second side end expansion portion and between two adjacent drug grooves and is located on the outer wall of the balloon component.

[0016] In this solution, a chamfered slope is preferably provided between the two side edges of each medicine groove and the outer wall of the balloon. If a sharp angle is formed between the two side edges of the medicine groove and the outer wall of the balloon, when the balloon is inflated, the two side edges of the medicine groove will be squeezed and deformed toward the inside of the medicine groove, and the design of the chamfered slope replaces the sharp corners to prevent the medicine from being stuck in the gap between the inner wall of the medicine groove and the two side edges, thereby reducing the blockage loss of the medicine.

[0017] In this solution, each of the medicine grooves has an expansion rebound portion on the inner wall of the balloon part behind it, and the expansion rebound portion is integrally formed with the balloon part. When the balloon part is inflated, the gas naturally pushes up the expansion rebound portion, so that all the medicines in the medicine grooves are output and laid on the blood vessel wall, preventing the medicines from accumulating at the bottom of the medicine groove and being unable to be discharged.

[0018] Preferably, at least two ball caps are bonded to the outer walls of the two halves of the elastic expansion bodies at opposite ends, and an elastic pull line is connected to the outer wall of each ball cap. The elastic pull line is tied to the outer wall of the half elastic expansion body, and the opposite ends of the elastic pull lines on the two halves of the elastic expansion body are fixedly connected to the first side expansion part and the second side expansion part respectively. When the elastically wrapped expansion body is synchronously expanded and propped up, the first tearable point line is disconnected, so that the two halves of the elastic expansion body retreat backwards under the action of their own elasticity, and at the same time, the elastic pull line elastically pulls the ball cap, and the ball cap is connected to the free end of the half elastic expansion body, so that after the half elastic expansion body is disconnected, the elastic pull line quickly pulls the ball cap, so that the two halves of the elastic expansion body are rolled up in opposite directions. The elastic pull line can further improve the disconnection and retreat efficiency of the half elastic expansion body.

[0019] Preferably, both ends of the balloon member are provided with side medicine bags located on the periphery of the outer tube, and the inner walls of the two side medicine bags are integrally connected with a separation ring body, and the perforations of the separation ring body are sleeved on the outer tube;

[0020] The separating ring body symmetrically divides the inner circle of the side end medicine bag into an expansion clamping cavity and a limiting rebound cavity. Each of the expansion clamping cavities and the inner wall located at the side end medicine bag has a second tearable point line, and the inside of the side end medicine bag has a medicine storage cavity for containing medicines.

[0021] Preferably, in this solution, the expansion clamping cavities of the two side end medicine pouches are frictionally clamped on the outer walls of the adjacent first side end expansion part and the second side end expansion part respectively. When the balloon is inflated, the first side expansion part and the second side expansion part are also inflated. At this time, the first side expansion part and the second side expansion part will squeeze the expansion clamping cavity of the two side medicine bag bags, and the inner walls of the two expansion clamping cavities are squeezed and deformed, so that the second easy-to-tear point line is disconnected. At this time, the two side medicine bag bags have not yet slipped off the first side expansion part and the second side expansion part, so the medicine pieces will not spill out. Under the squeezing force, the two expansion clamping cavities are gradually squeezed and rubbed against each other on the outer walls of the first side expansion part and the second side expansion part. When the two halves of the elastic expansion bodies are stretched open, under the impact of the elastic backward reaction force of the half elastic expansion bodies themselves and the elastic pull line, the two side medicine bag bags are completely hit from the first side expansion part and the second side expansion part and slide down to the side of the outer tube. As the side medicine bag bags slide, the medicine pieces in the medicine storage cavity are spilled onto the blood vessel wall, which plays a further therapeutic role after the medicine pieces on the outer wall of the balloon are laid.

[0022] In this solution, the two side medicine bags are preferably fixed with limiting rings on the opposite sides and on the periphery of the outer tube, and multiple extrusion springs are fixed on the outer walls of both sides of each of the separating ring bodies. The extrusion springs far away from the limiting rings elastically abut against the outer walls of the first side expansion part and the second side expansion part, respectively, while the extrusion springs close to the limiting rings elastically abut against the inner wall of the limiting rings. When the side medicine bag is hit by the half elastic expansion body, the elastic pull line and the ball head cap, the side medicine bag will slide on the periphery of the outer tube. At the same time, under the setting of the extrusion springs on both sides, when the side medicine bag slides, it drives the limiting ring to hit the first side expansion part, the second side expansion part and the limiting ring, so that the two side medicine bags will reciprocate and elastically shake between the limiting ring and the first side expansion part and the limiting ring and the second side expansion part, respectively, so as to further accelerate the shaking out of the drug from the drug storage cavity, accelerate the discharge of the drug, and improve the efficiency of the drug application on the blood vessel wall.

[0023] Compared with the prior art, the technical effects and advantages of the present invention are as follows:

[0024] The intracranial hypotension drug-coated balloon dilatation catheter has an elastically wrapped expansion body that tightly wraps the balloon component when not in use, forming a closed structure. This structure protects the drug components on the surface of the balloon component, preventing them from being washed away by blood or released prematurely before reaching the target location, and effectively protecting the integrity and activity of the drug components during the delivery process;

[0025] The drug coating protection component includes an elastic expansion body, which can fully enclose the balloon component to protect the drug component from the external environment. When the balloon component is inflated, the elastic expansion body will expand and open synchronously, exposing the drug component and laying it on the blood vessel wall, ensuring that the drug is released at the right time and location and that the drug can be concentrated in the area that needs to be treated, thereby increasing the local concentration of the drug. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 It is a structural schematic diagram of the present invention;

[0028] Figure 2 This is a schematic diagram of the structure of the first tearable point line disconnected state of the present invention;

[0029] Figure 3 It is a schematic diagram of the connection structure of the elastic pull wire of the present invention;

[0030] Figure 4 It is a structural schematic diagram of the medicine groove part of the present invention;

[0031] Figure 5 For the present invention Figure 4 A schematic diagram of the enlarged structure at A in the middle;

[0032] Figure 6 is a cross-sectional view of the balloon member of the present invention;

[0033] Figure 7 It is a schematic diagram of the structure in which the drug piece of the present invention is coated on the balloon piece;

[0034] Figure 8 This is a schematic diagram of the connection structure of the second tearable point line of the present invention;

[0035] Fig. 9 It is a schematic structural diagram of the extrusion spring of the present invention in a disassembled state;

[0036] Fig.10 It is a cross-sectional view of the side end medicine pouch of the present invention.

[0037] Description of reference numerals:

[0038] In the figure: 1. Balloon dilatation catheter assembly; 2. Outer tube; 3. Guide end tube; 4. Drug coating protection component; 5. Elastic wrapped expansion body; 6. First tear-off point line; 7. Side drug bag; 8. Balloon component; 9. Half elastic expansion body; 10. Limiting ring; 11. Elastic pull line; 12. Ball head cap; 13. Drug component; 14. First side end expansion part; 15. Second side end expansion part; 16. Drug groove part; 17. Rounded slope part; 18. Expansion rebound part; 19. Separation ring body; 20. Perforation; 21. Second tear-off point line; 22. Extrusion spring; 23. Expansion clamping cavity; 24. Limiting rebound cavity; 25. Drug storage cavity. DETAILED DESCRIPTION

[0039] In the following description, a large number of specific details are provided to provide a more thorough understanding of the present invention. However, it is apparent to those skilled in the art that the present invention can be implemented without one or more of these details. In other examples, in order to avoid confusion with the present invention, some technical features well known in the art are not described.

[0040] Unless otherwise defined, the up, down, left, right, front, back, inside and outside directions involved in this document are based on the up, down, left, right, front, back, inside and outside directions in the figures shown in the present invention, and are explained here together.

[0041] This embodiment provides Figures 1 to 10 The intracranial low-pressure drug-coated balloon dilatation catheter shown includes: a balloon dilatation catheter assembly 1, a balloon component 8, and a drug-coated protective component 4.

[0042] In this embodiment, the balloon dilatation catheter assembly 1 includes an outer tube 2 and a guide end tube 3 connected to one end of the outer tube 2; the outer tube 2 serves as a guide path to support and protect the internal balloon component 8 and the side end drug bag 7 assembly. The guide end tube 3 assists the catheter in entering the target position and helps the catheter to pass through the tortuous and complex blood vessel path through a soft design. This improves positioning accuracy and reduces surgical risks. It ensures smooth movement of the instrument in the blood vessel and minimal damage to surrounding tissues.

[0043] In this embodiment, the balloon member 8 is fixed to the peripheral outer wall of the outer tube 2 near one end of the guide end tube 3, and the peripheral outer wall of the balloon member 8 has a drug member 13; the balloon member 8 performs the main task of vascular dilation, expanding the narrowed or occluded blood vessel segment by inflation and restoring the normal blood flow channel.

[0044] In this embodiment, the drug coating protection component 4 includes an elastically wrapped expansion body 5 fully enclosed and wrapped around the side of the balloon component 8; the drug coating protection component 4 protects the drug coating from the external environment until the time of use. It is composed of an elastically wrapped expansion body 5, which remains in a closed state when not unfolded, ensuring the effectiveness of the drug component 13 until it is released to the designated area. The elastically wrapped expansion body 5 opens with the expansion of the balloon component 8, exposing the drug component 13. When the balloon is inflated, the elastically wrapped expansion body 5 expands synchronously, allowing the drug to directly contact the lesion site, achieving local drug administration and improving treatment efficiency.

[0045] In this embodiment, when the balloon member 8 is inflated, it squeezes the elastically wrapped expansion body 5, so that the elastically wrapped expansion body 5 is elastically expanded synchronously and then opens to expose the drug member 13, and the drug member 13 is applied to the blood vessel wall of the affected area.

[0046] In this embodiment, the elastically wrapped expansion body 5 includes two symmetrically arranged halves of the elastic expansion body 9, and the two halves of the elastic expansion body 9 are sealed and connected together at opposite ends through a first tear-off point line 6; the first tear-off point line 6 connects the two halves of the elastic expansion body 9 and breaks under the inflation pressure. The separation process of the elastically wrapped expansion body 5 is controlled to ensure the uniform distribution and release of the drug. The half elastic expansion body 9 forms a complete wrapping structure together with the elastically wrapped expansion body 5. After the balloon part 8 is expanded, they will separate to expose the drug part 13, allowing the drug to directly contact the blood vessel wall. And the two halves of the elastic expansion body 9 are arranged to be rolled back in opposite directions on the sides of the balloon part 8.

[0047] In this embodiment, the balloon member 8 includes a first side expansion portion 14 and a second side expansion portion 15, and the opposite ends of the two halves of the elastic expansion body 9 are fixedly wrapped around the outer wall of the first side expansion portion 14 and the second side expansion portion 15. The first side expansion portion 14 and the second side expansion portion 15 are part of the balloon member 8 and are responsible for the expansion of a specific area.

[0048] In this embodiment, a plurality of drug grooves 16 are provided in a circular array between the first side expansion portion 14 and the second side expansion portion 15 and on the peripheral outer wall of the balloon component 8; a portion of the drug components 13 are stored and accumulated in the drug grooves 16; another portion of the drug components 13 are coated on the first side expansion portion 14, the second side expansion portion 15, and between two adjacent drug grooves 16 and on the outer wall of the balloon component 8.

[0049] In this embodiment, a chamfered slope 17 is provided between the two side edges of each medicine groove 16 and the outer wall of the balloon 8. If a sharp angle is formed between the two side edges of the medicine groove 16 and the outer wall of the balloon 8, when the balloon 8 is inflated, the two side edges of the medicine groove 16 will be squeezed and deformed toward the inside of the medicine groove 16, and the design of the chamfered slope 17 replaces the sharp corners to prevent the medicine 13 from being stuck in the gap between the inner wall of the medicine groove 16 and the two side edges, thereby reducing the blockage loss of the medicine 13. The chamfered slope 17 prevents the edge of the medicine groove 16 from being too sharp, and the smooth transition design prevents the drug from getting stuck, reduces the loss of the drug, and ensures the effective use of the drug.

[0050] In this embodiment, each medicine groove 16 has an expansion rebound portion 18 behind it and located on the inner wall of the balloon member 8, and the expansion rebound portion 18 is integrally formed with the balloon member 8. When the balloon member 8 is inflated, the gas naturally pushes up the expansion rebound portion 18, so that all the medicine pieces 13 in the medicine groove 16 are output and laid on the blood vessel wall, preventing the medicine pieces 13 from accumulating at the bottom of the medicine groove 16 and being unable to be discharged. The expansion rebound portion 18 promotes the complete discharge of the medicine pieces 13 in the medicine groove 16, and deforms as the balloon expands, pushing the medicine out of the medicine groove, thereby increasing the speed and integrity of the drug release.

[0051] In this embodiment, at least two ball caps 12 are bonded to the outer wall of the opposite ends of the two half elastic expansion bodies 9, and the outer wall of each ball cap 12 is connected to an elastic pull line 11, which is tied to the outer wall of the half elastic expansion body 9. The opposite ends of the elastic pull lines 11 on the two half elastic expansion bodies 9 are fixedly connected to the first side expansion part 14 and the second side expansion part 15 respectively. When the elastic wrapped expansion body 5 is synchronously expanded and propped up, the first easy-to-tear break point line 6 is disconnected, so that the two half elastic expansion bodies 9 retreat backwards under the action of their own elasticity, and at the same time, the elastic pull line 11 elastically pulls the ball cap 12, and the ball cap 12 is connected to the free end of the half elastic expansion body 9, so that after the half elastic expansion body 9 is disconnected, the elastic pull line 11 quickly pulls the ball cap 12, so that the two half elastic expansion bodies 9 are rolled up in opposite directions. The elastic pull line 11 can further improve the disconnection and retreat efficiency of the half elastic expansion body 9.

[0052] In this embodiment, side medicine bags 7 are provided at both ends of the balloon member 8 and are located on the circumferential side of the outer tube 2. The inner ring walls of the two side medicine bags 7 are integrally connected with a separating ring body 19, and the perforations 20 of the separating ring body 19 are sleeved on the outer tube 2; the side medicine bags 7 store additional drugs and release them.

[0053] Specifically, the separation ring body 19 symmetrically divides the inner circle of the side end medicine bag 7 into an expansion clamping cavity 23 and a limit rebound cavity 24. Each expansion clamping cavity 23 and the inner wall of the side end medicine bag 7 have a second easy-tear point line 21, and the inside of the side end medicine bag 7 has a medicine storage cavity 25 for containing the medicine 13. The second easy-tear point line 21 is located in the expansion clamping cavity 23, controls the opening time of the side end medicine bag 7, breaks under the inflation pressure, allows the medicine to flow out of the medicine storage cavity 25, and realizes a controllable drug release mechanism.

[0054] In this embodiment, the expansion clamping cavities 23 of the two side end medicine pouches 7 are respectively frictionally clamped on the outer walls of the adjacent first side end expansion part 14 and the second side end expansion part 15. When the balloon part 8 is inflated, the first side end expansion part 14 and the second side end expansion part 15 are also inflated. At this time, the first side end expansion part 14 and the second side end expansion part 15 will squeeze the expansion clamping cavities 23 of the two side end medicine pouches 7. The inner walls of the two expansion clamping cavities 23 are squeezed and deformed, so that the second tear point line 21 is disconnected. At this time, the two side end medicine pouches 7 have not yet slipped off the first side end expansion part 14 and the second side end expansion part 15, so the medicine piece 13 will not spill out. Under the squeezing force, the two expansion clamping cavities 23 are gradually squeezed together. The outer walls of the first side expansion part 14 and the second side expansion part 15 rub and slide against each other, and when the two halves of the elastic expansion body 9 are stretched open, the two side medicine bags 7 are completely hit from the first side expansion part 14 and the second side expansion part 15 and slide to the side of the outer tube 2 under the elastic backward reaction force of the half elastic expansion body 9 itself and the elastic pull line 11. As the side medicine bag 7 slides, the medicine piece 13 in the medicine storage cavity 25 is spilled onto the blood vessel wall, which plays a further therapeutic role after the medicine piece 13 on the outer wall of the balloon piece 8 is laid.

[0055] Specifically, the elastic pull line 11 pulls the half elastic expansion body 9 to make it shrink quickly, accelerate the retraction speed of the half elastic expansion body 9, speed up the drug release process, and reduce the operation time. The ball head cap 12 fixes the position of the elastic pull line 11 to help the elastic pull line 11 to play a better role.

[0056] In this embodiment, the two side end medicine pouches 7 are fixed with limit rings 10 on the opposite sides and around the outer tube 2, and the limit rings 10 limit the movement range of the side end medicine pouches 7, and cooperate with the extrusion springs 22 to ensure the correct position of the medicine pouches, so as to ensure that the medicine is accurately applied to the target area. Multiple extrusion springs 22 are fixed to the outer walls of both sides of each separation ring body 19. The extrusion springs 22 away from the limiting ring 10 elastically abut against the outer walls of the first side expansion part 14 and the second side expansion part 15 respectively, while the extrusion springs 22 close to the limiting ring 10 elastically abut against the inner wall of the limiting ring 10. When the side medicine bag 7 is hit by the half elastic expansion body 9, the elastic pull line 11 and the ball head cap 12, the side medicine bag 7 will slide around the outer tube 2. At the same time, under the setting of the extrusion springs 22 on both sides, when the side medicine bag 7 slides, it will drive the limiting ring 10 to hit the first side expansion part 14, the second side expansion part 15 and the limiting ring 10, so that the two side medicine bags 7 will reciprocate elastically between the limiting ring 10 and the first side expansion part 14 and the limiting ring 10 and the second side expansion part 15 respectively, thereby further accelerating the shaking out of the drug piece 13 from the drug storage cavity 25, accelerating the discharge of the drug, and improving the efficiency of drug application on the blood vessel wall.

[0057] In this embodiment, when the elastically wrapped expansion body 5 is not in use, the elastically wrapped expansion body 5 tightly wraps the balloon part 8 to form a closed structure. This structure protects the drug part 13 on the surface of the balloon part 8 to prevent them from being washed away by blood or released prematurely before reaching the target position. With the help of the outer tube 2 and the guide end tube 3, the entire device is carefully delivered into the patient's vascular system and accurately positioned to the lesion site that needs to be treated. Once the target position is reached, the doctor will inject gas into the balloon part 8 through the catheter to make it start to expand. As the volume of the balloon part 8 increases, it will exert pressure on the surrounding elastically wrapped expansion body 5. Since the elastically wrapped expansion body 5 has a certain elasticity and ductility, when it is subjected to pressure from the balloon part 8, it will be forced to expand outward. In this process, the first tear-off point line 6 will break under a predetermined pressure, so that the two halves of the elastic expansion body 9 are separated and rolled back, thereby exposing the drug part 13 carried on the balloon part 8.

[0058] As the elastically wrapped expansion body 5 is opened, the drug piece 13 directly contacts the blood vessel wall. These drugs can be anti-proliferative drugs or other drugs that help prevent restenosis. They will adhere to the blood vessel wall and exert a local therapeutic effect. After the treatment is completed, the doctor will stop inflating the balloon piece 8 and deflate it, and then remove the entire device from the patient's body. At this time, the elastically wrapped expansion body 5 may partially shrink, but the main function has been completed, that is, to ensure that the drug is released at the right time and location. In short, the design of the elastically wrapped expansion body 5 is to ensure that the drug piece 13 can be accurately and effectively delivered to the lesion site, while providing a controllable way to expose and release the drug to achieve the best therapeutic effect.

[0059] In this embodiment, the first tear-off point line 6 is designed to automatically disconnect when a certain pressure or expansion degree is reached when the balloon part 8 is inflated. Specifically, its disconnection timing and conditions are as follows: when the doctor injects gas into the balloon part 8 through the catheter and the balloon begins to expand, the outer wall of the balloon part 8 will gradually expand outward. As the balloon part 8 expands, it will exert an increasing radial pressure on the elastically wrapped expansion body 5 wrapped outside it. This pressure will be transmitted to the first tear-off point line 6. The first tear-off point line 6 is a weak link pre-designed to have strength. When the inflation pressure of the balloon part 8 reaches the preset value, this weak link will not be able to withstand further pressure and will break. Usually, this preset value is carefully calculated based on clinical needs and material properties to ensure disconnection at the right time.

[0060] Specifically, once the first tear-off point line 6 is broken, the two halves of the elastic expansion body 9 will be pushed apart under the pressure of the balloon member 8 continuing to expand, and will be rolled back in opposite directions along their own elastic properties. This allows the drug member 13 to be exposed and contact the blood vessel wall, thereby achieving local drug administration. In short, the first tear-off point line 6 is broken during the inflation process of the balloon member 8 when the balloon expands to a certain extent, that is, when the designed pressure threshold is reached. This ensures that the drug member 13 can be released at the most appropriate time so that it can fully contact the lesion site and exert a therapeutic effect.

[0061] In this embodiment, the drug-coated protective component 4 plays a key protective role in the intracranial low-pressure drug-coated balloon dilatation catheter, ensuring that the drug piece 13 will not be washed away by the blood or released prematurely before reaching the target position. The following are the specific steps for the drug-coated protective component 4 to protect the drug: the drug-coated protective component 4 includes an elastically wrapped expansion body 5, which is tightly wrapped around the outer surface of the balloon piece 8 to form a complete closed structure. This closed design can effectively isolate the external environment and prevent the drug piece 13 from direct contact with blood or other body fluids, thereby preventing the drug from dissolving or losing prematurely. The elastically wrapped expansion body 5 is made of a polymer material with good biocompatibility. These materials have good adsorption and stability to drugs. The material needs to be able to resist the physiological environment in the blood vessel, such as enzymes in the blood, pH changes, etc., to ensure that the drug remains active during the delivery process.

[0062] Specifically, the elastically wrapped expansion body 5 provides a physical barrier to protect the drug from the friction and shear force that may be generated when the catheter moves in the blood vessel. The first tear-off point line 6 is a pre-set weak link, which breaks when the balloon member 8 is inflated to a predetermined pressure. When the first tear-off point line 6 breaks, the two halves of the elastic expansion body 9 will quickly separate and roll back, thereby exposing the drug member 13 and achieving precise release of the drug.

[0063] Specifically, the elastic pull line 11 is connected to the ball cap 12. When the first tear-off point line 6 breaks, the elastic pull line 11 will quickly pull the ball cap 12 to help the half elastic expansion body 9 separate faster. This mechanism improves the speed and efficiency of drug exposure and ensures that the drug can contact the lesion in the shortest time. The drug groove portion 16 is used to store part of the drug piece 13 and ensure that it is evenly distributed on the surface of the balloon piece 8. The design of the rounded slope portion 17 can prevent the drug from getting stuck at the edge of the drug groove portion 16, ensuring that the drug can be released smoothly from the drug groove. The side end drug bag 7 can provide additional drug storage space at both ends of the balloon piece 8, and control the release time of the drug through the second tear-off point line 21. When the balloon piece 8 expands, the drug in the side end drug bag 7 will also be released, further enhancing the local drug concentration and improving the therapeutic effect. Through the above design, the drug coating and wrapping protection component 4 not only protects the integrity and activity of the drug piece 13 during the transportation process, but also ensures that the drug can be accurately released at the right time and position, thereby achieving the best therapeutic effect.

[0064] Working principle:

[0065] The intracranial low-pressure drug-coated balloon dilatation catheter ensures that all instruments and operating areas are disinfected, the patient is given local anesthesia, and the lesion site is located through imaging equipment such as X-ray, CT or MRI. First, a thin guide wire is sent through the patient's vascular system to the target location, and the outer tube 2 is sent into the blood vessel along the guide wire until it reaches the vicinity of the lesion site. Imaging equipment is used to confirm that the catheter has been correctly placed at the location that needs treatment.

[0066] The guide end tube 3 in the outer tube 2 is used to further accurately guide the balloon 8 to the lesion site, and the imaging device is used again to confirm that the balloon 8 is located at the correct vascular stenosis or occlusion site. The syringe connected to the tail end of the outer tube 2 is used to inject gas into the balloon 8 to make the balloon 8 start to expand. As the balloon 8 expands, it applies pressure to the external elastic expansion body 5. When the preset pressure threshold is reached, the first tear point line 6 is broken, and the two halves of the elastic expansion body 9 are separated and rolled back, exposing the drug 13 on the surface of the balloon 8.

[0067] The balloon member 8 continues to expand, so that the drug member 13 directly contacts the blood vessel wall at the lesion site, and the drug components in the drug member 13 begin to penetrate into the blood vessel wall tissue, exerting a local therapeutic effect, such as inhibiting smooth muscle cell proliferation and preventing restenosis.

[0068] The drug storage cavity 25 inside the side medicine pouch 7 can store additional drugs. When the balloon component 8 is expanded, the first side expansion portion 14 and the second side expansion portion 15 will apply pressure to the expansion clamping cavity 23 of the side medicine pouch 7, causing the second tear point line 21 to break, thereby releasing the drugs stored in the drug storage cavity 25. These additional drugs will further enhance the local drug concentration and improve the therapeutic effect after the drugs on the outer wall of the balloon component 8 are released.

[0069] The elastic pull line 11 helps the half elastic expansion body 9 to be quickly rolled up after the first easy tear point line 6 breaks, thereby accelerating the drug exposure process. The extrusion spring 22 cooperates with the limiting ring 10 to generate a certain vibration when the side end drug bag 7 moves, which helps to distribute the drug more evenly on the blood vessel wall.

[0070] After the drug release is completed, the doctor extracts the gas in the balloon member 8 through a syringe to restore the balloon member 8 to its initial state, and slowly and carefully withdraws the entire device from the patient's body while monitoring whether any complications occur.

[0071] The patient's vital signs should be closely monitored after the operation to ensure that there is no bleeding or other complications. Reexamination with imaging equipment may be required for a period of time after the operation to evaluate the treatment effect.

[0072] It should be noted that, in this article, relational terms such as one and two are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions. The sentence "includes an element defined by ... does not exclude the existence of other identical elements in the process, method, article or device including the element".

[0073] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A drug-coated balloon dilatation catheter for intracranial hypotension, characterized in that: include: A balloon dilatation catheter assembly (1) comprises an outer tube (2) and a guide end tube (3); A balloon component (8) is fixed on the peripheral outer wall of the outer tube (2) close to one end of the guide end tube (3), and the peripheral outer wall of the balloon component (8) has a medicine component (13); The drug coating and protection component (4) comprises an elastically wrapped expansion body (5) which is fully enclosed and wrapped around the circumference of the balloon component (8); When the balloon component (8) is inflated, it squeezes the elastically wrapped expansion body (5), so that the elastically wrapped expansion body (5) is elastically expanded synchronously and then opens to expose the drug component (13), and the drug component (13) is applied to the blood vessel wall of the affected area.

2. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 1, characterized in that: The elastically wrapped expansion body (5) comprises two symmetrically arranged halves of the elastic expansion body (9), and opposite ends of the two halves of the elastic expansion body (9) are sealed and connected together via a first tearable point line (6); Furthermore, the two halves of the elastic expansion bodies (9) are arranged to be rolled back and away from each other on the peripheral side of the balloon component (8).

3. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 1, characterized in that: The balloon component (8) comprises a first side end expansion portion (14) and a second side end expansion portion (15), and the two opposite ends of the two half elastic expansion bodies (9) are fixedly wrapped around the peripheral outer walls of the first side end expansion portion (14) and the second side end expansion portion (15).

4. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 3, characterized in that: A plurality of medicine grooves (16) are provided in an annular array on the peripheral outer wall of the balloon member (8) between the first side end expansion portion (14) and the second side end expansion portion (15); A portion of the drug pieces (13) are stored and accumulated in the drug trough (16); Another part of the drug component (13) is coated on the first side end expansion portion (14), the second side end expansion portion (15) and between two adjacent drug groove portions (16) and is located on the outer wall of the balloon component (8).

5. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 4, characterized in that: A chamfered slope portion (17) is provided between the two side edges of each medicine groove portion (16) and the outer wall of the balloon member (8).

6. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 5, characterized in that: Each of the medicine grooves (16) has an expansion rebound portion (18) located behind the medicine groove portion (16) and on the inner wall of the balloon component (8), and the expansion rebound portion (18) is integrally formed with the balloon component (8).

7. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 6, characterized in that: At least two ball caps (12) are bonded to the outer walls of the opposite ends of the two half elastic expansion bodies (9), and the outer wall of each ball cap (12) is connected to an elastic pull wire (11), which is tightened on the outer wall of the half elastic expansion body (9). The opposite ends of the elastic pull wires (11) on the two half elastic expansion bodies (9) are fixedly connected to the first side expansion part (14) and the second side expansion part (15), respectively.

8. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 7, characterized in that: Side medicine bags (7) are provided at both ends of the balloon member (8) and are located on the circumferential side of the outer tube (2); the inner walls of the two side medicine bags (7) are integrally connected with a separation ring body (19); and the through hole (20) of the separation ring body (19) is sleeved on the outer tube (2); The separating ring body (19) symmetrically divides the inner circle of the side end medicine bag (7) into an expansion clamping cavity (23) and a limiting rebound cavity (24), and each of the expansion clamping cavities (23) and the inner wall of the side end medicine bag (7) has a second easy-to-tear point line (21), and the inside of the side end medicine bag (7) has a medicine storage cavity (25) for containing medicine pieces (13).

9. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 8, characterized in that: The expansion clamping cavities (23) of the two side end medicine pouches (7) are respectively frictionally clamped on the outer walls of the adjacent first side end expansion portion (14) and the second side end expansion portion (15).

10. The intracranial hypotension drug-coated balloon dilatation catheter according to claim 9, characterized in that: The two side end medicine bags (7) are both fixed with limiting rings (10) on the opposite sides and located around the outer tube (2), and the outer walls on both sides of each of the separation ring bodies (19) are fixed with a plurality of extrusion springs (22).

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