A three-stage dilatation balloon for preventing contrast agent leakage

Abstract

This invention belongs to the field of medical device technology, and specifically relates to a three-stage dilatation balloon for preventing contrast agent leakage. Addressing the problem that existing three-stage dilatation balloons rupture when the operating pressure exceeds the rated burst pressure, resulting in the instantaneous leakage of high-pressure contrast agent into the patient's body, leading to embolism or tissue damage, the following solution is proposed: an outer balloon body, an inner balloon body, a mesh reinforcement layer, a sheath, and a decompression balloon. The inner balloon body is located inside the outer balloon body, and the ultimate expansion diameter of the outer balloon body is larger than that of the inner balloon body. Both are made of different polymer materials, ensuring that the outer balloon body remains intact and forms a leakage-proof barrier when the inner balloon body ruptures. A mesh reinforcement layer is sandwiched between the inner and outer balloon bodies, and the intersection points of the mesh reinforcement layer are discretely connected to the outer wall of the inner balloon body via micro-anchors. This invention achieves automatic emergency storage and manual aspiration and removal of the contrast agent after balloon rupture, solving the safety problem of contrast agent leakage after overpressure rupture of existing balloons.

Description

Technical Field

[0001] This utility model relates to a three-stage dilatation balloon, specifically a three-stage dilatation balloon to prevent contrast agent leakage, and belongs to the field of medical device technology. Background Technology

[0002] Balloon catheters are widely used in percutaneous endovascular angioplasty to dilate stenosis or obstruction in coronary arteries, peripheral vessels, and non-vascular cavities (such as the digestive and urinary tracts), restoring patency at the narrowed site through balloon dilation. In interventional treatment of diseases such as acute myocardial infarction, balloon catheters are one of the core instruments. With the development of interventional techniques, three-stage dilatation balloons (progressive balloons) have emerged. These balloons use a pressure pump to inflate in stages, enabling multi-stage dilation diameters during a single intervention, avoiding the need for multiple catheter replacements required by traditional single-stage balloons, shortening the procedure time, and reducing the financial burden on patients. However, existing balloon catheters still have significant safety drawbacks: when the operating pressure exceeds the balloon's rated burst pressure, the balloon may rupture, and the contrast agent under high pressure may leak instantaneously into the bloodstream or body cavities, potentially leading to serious complications such as contrast agent embolism, allergic reactions, or tissue damage. This risk is particularly prominent in the clinical management of severely calcified lesions or complex stenosis.

[0003] To address the aforementioned issues, existing technologies have introduced multi-layer balloon designs. For example, CN210750823U discloses a balloon catheter whose balloon body comprises an inner balloon and an outer balloon. Both the inner and outer balloons are directly wrapped and fixed to the catheter, with the inner balloon located inside the outer balloon. A media channel is formed between the inner and outer balloons. The catheter has an outer media inlet and a media return outlet connected to the media channel. This design, by using a double-layer balloon body, allows the media to circulate within the media channel between the inner and outer balloons, primarily solving the technical problem of incomplete heat exchange on the inner surface of the balloon and improving heat exchange efficiency. For example, CN213100299U discloses a fold-resistant vasodilator balloon catheter. The balloon wall has a multi-layered structure, which allows the balloon to have a high rated burst pressure, thus preventing the "dog bone" phenomenon when dilating lesions with high rigidity. This design improves the overall pressure resistance of the balloon through a multi-layered structure; the technical idea is to "strengthen itself to prevent rupture." Another example is CN213466471U, which discloses a multi-layered balloon with at least two layers tightly bonded together. This multi-layered structure achieves ultra-high pressure resistance of 40 atm. However, the existing technologies have the following shortcomings: First, they lack a failure-safe design concept of "leakage prevention after rupture." Whether used for media circulation or high-pressure reinforcement, existing double-layer balloons lack an effective mechanism to prevent media leakage when either layer ruptures, and the high-pressure contrast agent may still directly enter the patient's body through the rupture opening. Second, in existing technologies, the inner and outer balloons are usually fixed in surface contact or form a connected media channel without an independent emergency media handling structure, making it impossible to actively guide the leaked contrast agent to external storage after rupture. Furthermore, existing double-layer balloons face the problem of the outer balloon body not retracting synchronously after expansion, affecting the safety and ease of operation of balloon withdrawal. Third, the sealing structure design at the connection of existing balloon catheters is relatively simple. The stacking of multiple balloon connection sections leads to an increase in local outer diameter, affecting the passage, and the connection is prone to stress concentration under high pressure. Utility Model Content

[0004] This invention addresses the problem of high-pressure contrast agent leakage into the patient's body, leading to embolism or tissue damage, when existing three-stage dilatation balloons rupture due to operating pressure exceeding the rated burst pressure. It provides a three-stage dilatation balloon body designed to prevent contrast agent leakage.

[0005] This utility model achieves the above-mentioned objective through the following technical solution: a three-stage dilatation balloon for preventing contrast agent leakage, comprising an outer balloon, an inner balloon, a mesh reinforcement layer, a sheath, and a decompression balloon. The inner balloon is located inside the outer balloon. The decompression balloon, the inner balloon, and the outer balloon are all sleeved on the sheath. The ultimate expansion diameter of the outer balloon is larger than that of the inner balloon. The inner balloon has a three-stage radial expansion elastic deformation state with pressure changes.

[0006] A mesh reinforcement layer is sandwiched between the inner and outer cysts. The mesh reinforcement layer is fixedly connected to the inner wall of the outer cyst, and the intersection points of the mesh lines of the mesh reinforcement layer are discretely connected to the outer wall of the inner cyst.

[0007] The outer wall of the sheath near the front end has a concave stepped surface, the inner bladder is fixedly connected in the concave stepped surface, and the outer bladder is sealed to the inner bladder.

[0008] The sheath has independent filling and decompression chambers. The filling chamber is connected to the inner cavity of the inner sac, and the decompression chamber is connected between the inner sac and the decompression balloon. A miniature one-way valve is fixedly connected to the sheath and connects the decompression chamber to the inner cavity of the inner sac.

[0009] As a further embodiment of this utility model: the outer bladder includes an integrally formed outer middle section, and outer diameter-changing sections and outer connecting sections located at both ends of the outer middle section; the inner bladder includes an integrally formed inner middle section, and inner diameter-changing sections and inner connecting sections located at both ends of the inner middle section; each section of the inner bladder corresponds to and is adapted to each section of the outer bladder; both the outer diameter-changing section and the inner diameter-changing section are tapered structures with smooth transitions; the inner connecting section is fixedly sleeved on both ends of the concave stepped surface; a portion of the outer connecting section is fixedly sleeved on the outside of the inner connecting section; and another portion of the outer connecting section is fixedly sleeved on the tube body of the sheath tube where the concave stepped surface is not opened.

[0010] As a further embodiment of this utility model: a mesh reinforcement layer is sandwiched between the outer middle section of the outer capsule and the inner middle section of the inner capsule. A number of micro anchors are provided between the mesh reinforcement layer and the inner middle section. One end of the micro anchor is fixedly connected to the outer wall of the inner capsule, and the other end of the micro anchor is connected to the intersection point of the mesh lines of the mesh reinforcement layer. A gap is formed between the inner capsule and the outer capsule through the micro anchors.

[0011] As a further improvement of this utility model: an annular limiting groove is provided on the outer wall of the outer docking section of the outer bladder, and an annular reinforcing rib is fixedly connected in the annular limiting groove.

[0012] As a further improvement of this utility model: the miniature check valve is a pressure-sensitive check valve, and the opening threshold of the miniature check valve is adapted to the rated burst pressure of the inner bladder. The filling cavity is provided with several filling holes on the end wall facing the inner bladder, and the filling cavity is connected to the inner cavity of the inner bladder through the filling holes.

[0013] As a further embodiment of this utility model: several developing points are embedded in the inner walls of both ends of the middle section of the outer layer, and the several developing points are evenly distributed along the circumference of the middle section of the outer layer. A developing ring is sleeved on the outer wall of the tube body with an inwardly concave stepped surface, and the connection position of the developing ring corresponds to both ends of the middle section of the inner layer.

[0014] As a further embodiment of this utility model: the sheath tube body is also provided with a guide wire cavity, which is independent of the filling cavity and the decompression cavity. The front end of the sheath tube is fixedly connected to a tube front soft head, and the rear end of the sheath tube is fixedly connected to a tube tail connector. The filling cavity and the guide wire cavity are both connected to the tube tail connector.

[0015] As a further improvement of this utility model: two connecting pipes are connected to the tube tail connector, one of which is connected to the filling cavity through the tube tail connector, and the other connecting pipe is connected to the guide wire cavity through the tube tail connector.

[0016] As a further improvement of this utility model: the walls of the filling cavity and the decompression cavity are fixedly connected with a number of auxiliary support blocks, which are evenly distributed along the circumference of the filling cavity and the decompression cavity, and the auxiliary support blocks are integrally formed with the sheath.

[0017] The beneficial effects of this utility model are:

[0018] 1. The utility model comprises an outer capsule, an inner capsule, a mesh reinforcement layer, a sheath, and a decompression balloon. The inner capsule is located inside the outer capsule. The decompression balloon, the inner capsule, and the outer capsule are all fitted onto the sheath. The ultimate expansion diameter of the outer capsule is larger than that of the inner capsule. The inner capsule exhibits a three-stage radial expansion elastic deformation state with pressure changes. The outer and inner capsules are made of different polymer materials. The inner capsule achieves three-stage expansion under rated filling pressure and provides support for the outer capsule. The outer capsule maintains structural integrity when the inner capsule ruptures due to overpressure, forming a contrast agent leakage barrier. Contrast agent is injected into the inner cavity of the inner capsule through the filling cavity. The inner capsule sequentially achieves three-stage expansion under rated filling pressure. At this time, the inner capsule acts as the main... The working layer not only provides stable internal support for the outer capsule, ensuring precise control of the expansion diameter, but also, due to the high hardness and support of the polymer material used, can effectively dilate narrowed lesions. When the filling pressure exceeds the inner capsule's tolerance limit due to operational errors or extremely hard lesions, the inner capsule ruptures due to overpressure. At this time, because the outer capsule's limit expansion diameter is greater than the inner capsule's expansion diameter before rupture, the outer capsule has not yet reached its physical expansion limit in terms of material or structure. Therefore, it can maintain structural integrity, forming a reliable contrast agent leakage barrier, sealing the high-pressure contrast agent inside the outer capsule, preventing it from leaking into the patient's body, and avoiding serious complications such as contrast agent embolism, allergic reactions, or tissue damage.

[0019] 2. In this invention, a mesh reinforcement layer is sandwiched between the inner and outer capsules. The mesh reinforcement layer is fixedly connected to the inner wall of the outer capsule, and the intersection points of the mesh lines of the mesh reinforcement layer are discretely connected to the outer wall of the inner capsule. When the inner capsule ruptures, the mesh reinforcement layer can act as the first buffer barrier to withstand the instantaneous impact of the high-pressure contrast agent, and its mesh structure can evenly distribute the impact force to the entire inner wall of the outer capsule, avoiding excessive local pressure that could lead to secondary rupture of the outer capsule. The discrete connection between the mesh reinforcement layer and the outer wall of the inner capsule means that they are fixed only at specific points, while maintaining gaps in other areas. This ensures that the inner capsule can provide sufficient support for the outer capsule during normal expansion, while avoiding stress concentration caused by surface contact fixation. Furthermore, when the inner capsule ruptures, the discrete connection points can also play a traction role, preventing asymmetric expansion caused by uneven local pressure and improving the accuracy of three-stage expansion.

[0020] 3. The sheath tube of this utility model has a concave stepped surface on the outer wall near the front end. The inner bladder is fixedly connected in the concave stepped surface, and the outer bladder is sealed to the inner bladder. The concave stepped surface makes the connection part of the inner bladder radially concave inward, avoiding the problem of excessive local outer diameter caused by the stacking of the connection parts of the inner and outer bladders in the same axial position. The connection sealing line of the inner bladder and the connection sealing line of the outer bladder are staggered in the axial direction. When the balloon expands under high pressure, the axial tensile force generated at the connection of the two bladders is distributed to two stepped surfaces of different diameters, reducing the stress concentration at a single connection point and effectively preventing the connection from failing or falling off under high pressure.

[0021] 4. The sheath of this invention has an independent filling chamber and a decompression chamber. The filling chamber is connected to the inner cavity of the inner sac, and the decompression chamber is connected between the inner sac and the decompression balloon. A miniature one-way valve fixedly connected to the sheath connects the decompression chamber and the inner cavity of the inner sac. Under normal use, the filling chamber is responsible for delivering contrast agent to the inner sac to achieve three-stage dilation, while the decompression chamber is closed and the miniature one-way valve remains closed. When the inner sac ruptures, the pressure inside the sac exceeds the preset opening threshold of the miniature one-way valve, which automatically opens, guiding the leaked contrast agent through the decompression chamber to the decompression balloon outside the body for storage, thus achieving a passive emergency fluid storage function. The independent design of the filling chamber and the decompression chamber ensures that the normal filling function and the emergency treatment function do not interfere with each other. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0023] Figure 2 This is a schematic diagram of the cross-sectional structure of the outer and inner capsules of this utility model;

[0024] Figure 3 This utility model Figure 2 Schematic diagram of the split structure of the annular reinforcing rib at point A;

[0025] Figure 4 This is a schematic diagram of the connection structure between the outer middle section, the inner middle section, and the mesh reinforcement layer of this utility model;

[0026] Figure 5 This utility model Figure 4 Schematic diagram of the structure at point B;

[0027] Figure 6 This is a schematic diagram of the connection structure between the middle section of the outer layer and the developing point of this utility model;

[0028] Figure 7 This is a schematic diagram of the internal structure of the sheath of this utility model;

[0029] Figure 8 This is a schematic diagram of the internal structure of the concave stepped surface portion of the sheath tube of this utility model;

[0030] Figure 9 This is a cross-sectional structural diagram of the decompression balloon and its connecting parts of the present invention.

[0031] In the diagram: 1. Outer capsule; 11. Outer middle section; 12. Outer diameter-changing section; 13. Outer connecting section; 14. Annular limiting groove; 15. Imaging point; 2. Inner capsule; 21. Inner middle section; 22. Inner diameter-changing section; 23. Inner connecting section; 3. Annular reinforcing rib; 4. Mesh reinforcement layer; 41. Micro-anchor; 5. Sheath; 51. Tube tail connector; 52. Concave stepped surface; 53. Imaging ring; 54. Filling cavity; 55. Decompression cavity; 56. Auxiliary support block; 57. Filling hole; 58. Miniature one-way valve; 59. Guide wire cavity; 6. Decompression balloon; 7. Tube front soft tip; 8. Connecting tube. Detailed Implementation

[0032] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0033] Example 1

[0034] like Figures 1 to 9As shown, a three-stage dilatation balloon for preventing contrast agent leakage includes an outer balloon 1, an inner balloon 2, a mesh reinforcement layer 4, a sheath 5, and a decompression balloon 6. The inner balloon 2 is located inside the outer balloon 1. The decompression balloon 6, the inner balloon 2, and the outer balloon 1 are all fitted onto the sheath 5. The ultimate expansion diameter of the outer balloon 1 is larger than that of the inner balloon 2. The inner balloon 2 exhibits a three-stage radial expansion elastic deformation state with pressure changes. It should be noted that the outer balloon 1 and the inner balloon 2 are made of different polymer materials. The inner balloon 2 achieves three-stage expansion under rated filling pressure and provides support for the outer balloon 1. The outer balloon 1 maintains structural integrity when the inner balloon 2 ruptures due to overpressure, forming a barrier against leakage of diluted contrast agent. Diluted contrast agent is injected into the inner cavity of the inner balloon 2 through the filling cavity 54. The inner balloon 2 undergoes three-stage expansion under rated filling pressure. In the current three-stage dilation, the inner capsule 2, as the main working layer, not only provides stable internal support for the outer capsule 1, ensuring precise control of the dilation diameter, but also, due to the high hardness and support of the polymer material used, can effectively dilate the narrowed lesion tissue. When the filling pressure exceeds the bearing limit of the inner capsule 2 due to operational errors or the extreme hardness of the lesion, the inner capsule 2 ruptures due to overpressure. At this time, since the ultimate dilation diameter of the outer capsule 1 is greater than the dilation diameter of the inner capsule 2 before rupture, the outer capsule 1 has not yet reached its physical dilation limit in terms of material or structure. Therefore, it can maintain structural integrity and form a reliable anti-leakage barrier for diluted contrast agent, sealing the high-pressure diluted contrast agent inside the outer capsule 1 to prevent it from leaking into the patient's body and avoiding serious complications such as embolism of diluted contrast agent, allergic reactions, or tissue damage.

[0035] A mesh reinforcement layer 4 is sandwiched between the inner capsule 2 and the outer capsule 1. The mesh reinforcement layer 4 is fixedly connected to the inner wall of the outer capsule 1, and the intersection points of the mesh lines of the mesh reinforcement layer 4 are discretely connected to the outer wall of the inner capsule 2. When the inner capsule 2 ruptures, the mesh reinforcement layer 4 can act as the first buffer barrier to withstand the instantaneous impact of the contrast agent after high-pressure dilution, and its mesh structure can evenly distribute the impact force to the entire inner wall of the outer capsule 1, avoiding excessive local pressure that could lead to secondary rupture of the outer capsule 1. The discrete connection between the mesh reinforcement layer 4 and the outer wall of the inner capsule 2 means that they are fixed only at specific points, while maintaining gaps in other areas. This ensures that the inner capsule 2 can provide sufficient support for the outer capsule 1 during normal expansion, while avoiding stress concentration caused by surface contact fixation. Furthermore, when the inner capsule 2 ruptures, the discrete connection points can also play a traction role, avoiding asymmetric expansion caused by uneven local pressure, and improving the accuracy of the three-stage expansion.

[0036] The outer wall of the sheath 5 near the front end has a concave stepped surface 52. The inner bladder 2 is fixedly connected in the concave stepped surface 52. The outer bladder 1 is sealed to the inner bladder 2. The concave stepped surface 52 makes the connection part of the inner bladder 2 radially concave inward, avoiding the problem of excessive local outer diameter caused by the stacking of the connection parts of the inner bladder 2 and the outer bladder 1 in the same axial position. The connection sealing line of the inner bladder 2 and the connection sealing line of the outer bladder 1 are staggered in the axial direction. When the balloon expands under high pressure, the axial tension generated at the connection of the two bladders is distributed to two stepped surfaces of different diameters, reducing the stress concentration at a single connection point and effectively preventing the connection from failing or falling off under high pressure.

[0037] The sheath 5 has an independent filling chamber 54 and a decompression chamber 55. The filling chamber 54 is connected to the inner cavity of the inner capsule 2, and the decompression chamber 55 is connected between the inner capsule 2 and the decompression balloon 6. A miniature one-way valve 58 is fixedly connected to the sheath 5 between the decompression chamber 55 and the inner cavity of the inner capsule 2. Under normal use, the filling chamber 54 is responsible for delivering diluted contrast agent to the inner capsule 2 to achieve three-stage expansion. The decompression chamber 55 is closed, and the miniature one-way valve 58 remains closed. When the inner capsule 2 ruptures, the pressure inside the capsule exceeds the preset opening threshold of the miniature one-way valve 58. The miniature one-way valve 58 automatically opens, guiding the leaked diluted contrast agent through the decompression chamber 55 to the decompression balloon 6 outside the body for storage, realizing a passive emergency fluid storage function. The independent design of the filling chamber 54 and the decompression chamber 55 ensures that the normal filling function and the emergency treatment function do not interfere with each other.

[0038] Example 2

[0039] Improvements based on Example 1:

[0040] like Figures 1 to 6As shown, the outer sheath 1 includes an integrally formed outer middle section 11, and outer diameter-changing sections 12 and outer connecting sections 13 located at both ends of the outer middle section 11. The inner sheath 2 includes an integrally formed inner middle section 21, and inner diameter-changing sections 22 and inner connecting sections 23 located at both ends of the inner middle section 21. Each segment of the inner sheath 2 corresponds to and fits each segment of the outer sheath 1. Both the outer diameter-changing section 12 and the inner diameter-changing section 22 are smoothly transitioned conical structures. The inner connecting section 23 is fixedly sleeved on both ends of the concave stepped surface 52. A portion of the outer connecting section 13 is fixedly sleeved on the outside of the inner connecting section 23, and another portion of the outer connecting section 13 is fixedly sleeved on the tube body of the sheath 5 where the concave stepped surface 52 is not opened. The outer middle section 11 and the inner middle section 21 are integrally formed. Segment 21, as the main working area of ​​the balloon, undertakes the core function of dilating stenotic lesions. Its straight cylindrical structure ensures uniform radial expansion force when inflated, avoiding tissue damage caused by local stress concentration. Both the outer diameter-changing segment 12 and the inner diameter-changing segment 22 are designed as smoothly transitioning conical structures, so that the diameter change of the balloon from the working segment to the connecting segment is gradual during expansion, eliminating stress concentration points caused by abrupt diameter changes. The staggered connection structure between the inner connecting segment 23 and the outer connecting segment 13 makes the connection area between the inner balloon body 2 and the outer balloon body 1 form a stepped distribution in the axial direction, effectively dispersing the axial tension borne by the connection point during balloon expansion, further improving the safety of the balloon catheter in extreme situations.

[0041] Furthermore, the mesh reinforcement layer 4 is sandwiched between the outer middle section 11 of the outer capsule 1 and the inner middle section 21 of the inner capsule 2. Several micro-anchors 41 are disposed between the mesh reinforcement layer 4 and the inner middle section 21. One end of each micro-anchor 41 is fixedly connected to the outer wall of the inner capsule 2, and the other end is connected to the intersection point of the mesh lines of the mesh reinforcement layer 4. A gap is formed between the inner capsule 2 and the outer capsule 1 through the micro-anchors 41. During the inflation and expansion of the balloon, the micro-anchors 41 can transmit the expansion force of the inner capsule 2 to the mesh reinforcement layer 4 and the outer capsule 1 through discrete points. The inner capsule 1 ensures uniform force transmission; when the balloon deflates and retracts, the micro-anchor 41 can transfer the retraction force of the inner capsule 2 to the outer capsule 1, causing the outer capsule 1 to retract synchronously, effectively solving the problem that the outer capsule 1 cannot retract autonomously after the double-layer balloon is expanded; the gap formed by the micro-anchor 41 between the two layers acts as a buffer space during normal expansion, absorbing some of the deformation energy during the expansion process; when the inner capsule 2 ruptures, the gap provides a temporary containment space for the leaked diluted contrast agent, avoiding the instantaneous pressure impact directly acting on the inner wall of the outer capsule 1.

[0042] Furthermore, an annular limiting groove 14 is provided on the outer wall of the outer docking section 13 of the outer capsule 1. An annular reinforcing rib 3 is fixedly connected in the annular limiting groove 14. The annular limiting groove 14 is located on the outer wall of the outer docking section 13. Its concave structure provides positioning space for the annular reinforcing rib 3, preventing the annular reinforcing rib 3 from axially shifting or circumferentially deviating during the expansion and contraction of the balloon. This ensures that the annular reinforcing rib 3 is always in the connection area that needs the most reinforcement. The annular reinforcing rib 3 is fixedly connected in the annular limiting groove 14. By increasing the local wall thickness, the tensile strength and tear resistance of the outer docking section 13 under high pressure are improved.

[0043] Furthermore, the miniature check valve 58 is a pressure-sensitive check valve, and its opening threshold is adapted to the rated burst pressure of the inner bladder 2. The filling chamber 54 has several filling holes 57 on its end wall facing the inner bladder 2. The filling chamber 54 is connected to the inner cavity of the inner bladder 2 through the filling holes 57. The miniature check valve 58 adopts a pressure-sensitive design to ensure that the opening timing of the miniature check valve 58 is highly synchronized with the rupture timing of the inner bladder 2. This avoids both erroneous opening under normal expansion pressure due to an excessively low opening threshold, thus preventing interference with normal use, and erroneous opening due to an excessively high opening threshold. After the inner capsule 2 ruptures, the micro check valve 58 fails to open in time and loses its emergency liquid storage function. When the inner capsule 2 ruptures, the capsule pressure rises to the opening threshold of the micro check valve 58, and the micro check valve 58 immediately opens automatically, introducing the high-pressure diluted contrast agent into the decompression chamber 55 and finally storing it in the decompression balloon 6, realizing fully automatic emergency treatment. Several filling holes 57 are opened so that the diluted contrast agent can enter the inner cavity of the inner capsule 2 evenly in a multi-channel manner, avoiding the local jet impact caused by single-hole injection and reducing the scouring and wear on the inner wall of the inner capsule 2.

[0044] Furthermore, several imaging points 15 are embedded in the inner walls of both ends of the outer middle section 11. These imaging points 15 are evenly distributed circumferentially along the outer middle section 11. The outer wall of the sheath 5, which has an inwardly concave stepped surface 52, is fitted with an imaging ring 53. The connection positions of the imaging ring 53 correspond to the two ends of the inner middle section 21. The imaging points 15 are evenly distributed circumferentially, so that under X-ray fluoroscopy, regardless of the rotation angle of the balloon catheter in the body, the doctor can clearly observe the boundary positions of both ends of the outer middle section 11, thereby accurately determining the positioning of the balloon at the stenotic lesion and ensuring that the outer middle section 11 completely covers the lesion area that needs to be dilated. The imaging ring 53 fitted on the sheath 5 and the imaging points 15 form a double imaging marker, which can help the doctor dynamically monitor the morphological changes of the balloon during balloon dilation. When an abnormal increase in the axial distance between the imaging points 15 is found or an unexpected change in the relative position of the imaging points 15 and the imaging ring 53 is found, it can be determined in time whether the balloon has been over-dilated or ruptured.

[0045] like Figure 1 , Figures 7 to 9 As shown, the sheath 5 also has a guidewire lumen 59. The guidewire lumen 59 is independent of the filling lumen 54 and the decompression lumen 55. The front end of the sheath 5 is fixedly connected to the inlet soft tip 7, and the rear end of the sheath 5 is fixedly connected to the tail connector 51. The filling lumen 54 and the guidewire lumen 59 are both connected to the tail connector 51. The independent design of the guidewire lumen 59 from the filling lumen 54 and the decompression lumen 55 ensures that when the guidewire is moved forward, backward, or rotated through the guidewire lumen 59, it will not interfere with the fluid in the filling lumen 54 and the decompression lumen 55, ensuring that balloon inflation and decompression operations can be performed independently under any circumstances. When the inner balloon body 2 ruptures and the decompression lumen 55 is used for emergency aspiration, the presence of the guidewire will not affect the aspiration efficiency of the decompression lumen 55. When the balloon catheter passes through a narrow lesion or a tortuous blood vessel, the inlet soft tip 7 fixedly connected to the front end of the sheath 5 can conform to the natural curvature of the blood vessel, avoiding scratches or perforations to the inner wall of the blood vessel.

[0046] Furthermore, two connecting tubes 8 are connected to the end connector 51. One connecting tube 8 is connected to the filling chamber 54 through the end connector 51, and the other connecting tube 8 is connected to the guidewire chamber 59 through the end connector 51. The two connecting tubes 8 separate the filling function and the guidewire function outside the body. The connecting tube 8 corresponding to the filling chamber 54 can be connected to a pressure pump or syringe for balloon inflation and depressurization, while the connecting tube 8 corresponding to the guidewire chamber 59 serves as the guidewire inlet and operation channel, avoiding the risk of misoperation due to interface confusion.

[0047] Furthermore, the walls of both the filling chamber 54 and the decompression chamber 55 are fixedly connected with several auxiliary support blocks 56. These auxiliary support blocks 56 are evenly distributed circumferentially along the filling chamber 54 and the decompression chamber 55, and the auxiliary support blocks 56 are integrally formed with the sheath 5. The even distribution of the auxiliary support blocks 56 circumferentially along the filling chamber 54 and the decompression chamber 55 forms a uniform support skeleton inside the sheath 5, effectively preventing the filling chamber 54 and the decompression chamber 55 from collapsing and deforming under negative pressure. This ensures that even during suction or decompression, the two chambers can maintain a smooth flow section, ensuring the smooth operation of balloon inflation and decompression.

[0048] Working principle: During the procedure, the balloon catheter is pushed along the guidewire inside the guidewire lumen 59 to the narrowed lesion in the body's physiological cavity. It is connected to a pressure pump via the end connector 51 and connecting tube 8. The diluted contrast agent enters the inner cavity of the inner balloon 2 through the filling lumen 54 and filling orifice 57. The inner balloon 2 expands radially in three stages according to the rated filling pressure applied by the pressure pump. The middle section 21 of the inner layer expands outward as the main working layer, and the expansion force is transmitted to the mesh reinforcement layer 4 through the micro-anchor 41 for further expansion. The transmission to the outer capsule 1 causes the middle section 11 of the outer layer to expand synchronously. The conical structure of the inner variable diameter section 22 and the outer variable diameter section 12 achieves a smooth transition in diameter. The inner docking section 23 is fixed on the concave stepped surface 52 of the sheath tube 5. The outer docking section 13 is partially sleeved on the outside of the inner docking section 23 and partially sleeved on the main body of the sheath tube 5, forming a stepped sealing structure. The annular reinforcing rib 3 enhances the strength of the connection. The imaging point 15 and the imaging ring 53 assist in positioning the working section of the balloon under X-ray.

[0049] When the inner capsule 2 ruptures due to the operating pressure exceeding the rated burst pressure, the high-pressure diluted contrast agent instantly rushes into the gap between the inner capsule 2 and the outer capsule 1. The mesh reinforcement layer 4 first bears the impact and evenly distributes the pressure to the inner wall of the outer capsule 1. Since the ultimate expansion diameter of the outer capsule 1 is greater than the expansion diameter of the inner capsule 2 before rupture, the outer capsule 1 maintains structural integrity. When the inner capsule 2 ruptures, the capsule pressure exceeds the preset opening threshold of the micro check valve 58, triggering the micro check valve 58 to open automatically. The leaked diluted contrast agent is guided to the extracorporeal decompression balloon 6 through the decompression chamber 55 for storage, realizing passive emergency liquid storage.

[0050] After emergency treatment is completed, the pressure of the inner bladder 2 is released through the filling cavity 54. When the inner bladder 2 retracts, the mesh reinforcement layer 4 and the outer bladder 1 retract synchronously through the micro anchor 41. The auxiliary support block 56 prevents the decompression cavity 55 from collapsing under negative pressure, ensuring that the aspiration channel is unobstructed. Finally, the entire balloon retracts to its initial shape and is withdrawn from the body along with the sheath 5. The soft tip 7 at the front of the tube protects the inner wall of the blood vessel from damage during the pushing and withdrawal process.

[0051] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered illustrative and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0052] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A three-stage dilatation balloon for preventing contrast agent leakage, comprising an outer balloon (1), an inner balloon (2), a mesh reinforcement layer (4), a sheath (5), and a decompression balloon (6), characterized in that: The inner bladder (2) is located inside the outer bladder (1). The decompression balloon (6), the inner bladder (2) and the outer bladder (1) are all fitted onto the tube body of the sheath (5). The ultimate expansion diameter of the outer bladder (1) is greater than that of the inner bladder (2). The inner bladder (2) has a three-stage radial expansion elastic deformation state with pressure changes. A mesh reinforcement layer (4) is sandwiched between the inner cyst (2) and the outer cyst (1). The mesh reinforcement layer (4) is fixedly connected to the inner wall of the outer cyst (1), and the intersection points of the mesh lines of the mesh reinforcement layer (4) are discretely connected to the outer wall of the inner cyst (2). The outer wall of the sheath (5) near the front end is provided with a concave stepped surface (52), the inner bladder (2) is fixedly connected in the concave stepped surface (52), and the outer bladder (1) is sealed to the inner bladder (2). The sheath (5) has an independent filling chamber (54) and a decompression chamber (55). The filling chamber (54) is connected to the inner cavity of the inner bladder (2). The decompression chamber (55) is connected between the inner bladder (2) and the decompression balloon (6). A miniature one-way valve (58) is fixedly connected to the sheath (5) between the decompression chamber (55) and the inner cavity of the inner bladder (2).

2. The three-stage dilatation balloon for preventing contrast agent leakage according to claim 1, characterized in that: The outer bladder (1) includes an integrally formed outer middle section (11), and an outer variable diameter section (12) and an outer docking section (13) located at both ends of the outer middle section (11). The inner bladder (2) includes an integrally formed inner middle section (21), and an inner variable diameter section (22) and an inner docking section (23) located at both ends of the inner middle section (21). Each segment of the inner bladder (2) corresponds to and is adapted to each segment of the outer bladder (1). Both the outer variable diameter section (12) and the inner variable diameter section (22) are tapered structures with smooth transitions. The inner docking section (23) is fixedly sleeved on both ends of the concave stepped surface (52). A portion of the outer docking section (13) is fixedly sleeved on the outside of the inner docking section (23), and another portion of the outer docking section (13) is fixedly sleeved on the tube body of the sheath tube (5) where the concave stepped surface (52) is not opened.

3. The three-stage dilatation balloon body for preventing contrast agent leakage according to claim 2, characterized in that: The mesh reinforcement layer (4) is sandwiched between the outer middle section (11) of the outer capsule (1) and the inner middle section (21) of the inner capsule (2). A number of micro anchors (41) are provided between the mesh reinforcement layer (4) and the inner middle section (21). One end of the micro anchor (41) is fixedly connected to the outer wall of the inner capsule (2), and the other end of the micro anchor (41) is connected to the intersection point of the mesh lines of the mesh reinforcement layer (4). A gap is formed between the inner capsule (2) and the outer capsule (1) through the micro anchors (41).

4. The three-stage dilatation balloon body for preventing contrast agent leakage according to claim 2, characterized in that: The outer wall of the outer docking section (13) of the outer bladder (1) is provided with an annular limiting groove (14), and an annular reinforcing rib (3) is fixedly connected in the annular limiting groove (14).

5. The three-stage dilatation balloon body for preventing contrast agent leakage according to claim 1, characterized in that: The miniature check valve (58) is a pressure-sensitive check valve, and the opening threshold of the miniature check valve (58) is adapted to the rated burst pressure of the inner bladder (2). The filling cavity (54) has several filling holes (57) on the end wall facing the inner bladder (2), and the filling cavity (54) is connected to the inner cavity of the inner bladder (2) through the filling holes (57).

6. The three-stage dilatation balloon body for preventing contrast agent leakage according to claim 2, characterized in that: The inner walls of both ends of the outer middle section (11) are provided with a number of developing points (15), and the developing points (15) are evenly distributed along the circumference of the outer middle section (11). The outer wall of the sheath tube (5) with the concave stepped surface (52) is provided with a developing ring (53), and the connection position of the developing ring (53) corresponds to both ends of the inner middle section (21).

7. The three-stage dilatation balloon body for preventing contrast agent leakage according to claim 1, characterized in that: The sheath (5) also has a guide wire cavity (59) in its body. The guide wire cavity (59) is independent of the filling cavity (54) and the decompression cavity (55). The front end of the sheath (5) is fixedly connected to a tube front soft head (7), and the rear end of the sheath (5) is fixedly connected to a tube tail connector (51). The filling cavity (54) and the guide wire cavity (59) are both connected to the tube tail connector (51).

8. The three-stage dilatation balloon body for preventing contrast agent leakage according to claim 7, characterized in that: Two connecting pipes (8) are connected to the tube end connector (51). One of the connecting pipes (8) is connected to the filling cavity (54) through the tube end connector (51), and the other connecting pipe (8) is connected to the guide wire cavity (59) through the tube end connector (51).

9. The three-stage dilatation balloon for preventing contrast agent leakage according to claim 1, characterized in that: The walls of the filling cavity (54) and the decompression cavity (55) are fixedly connected with a number of auxiliary support blocks (56). The auxiliary support blocks (56) are evenly distributed along the circumference of the filling cavity (54) and the decompression cavity (55), and the auxiliary support blocks (56) and the sheath (5) are integrally formed.

Images