Balloon catheter

Abstract

The present invention relates to the technical field of medical devices, and discloses a balloon catheter, comprising: an outer tube body, whose inner peripheral wall encloses an outer tube cavity; an inner tube body, which is embedded in the outer tube cavity; the inner peripheral wall of the inner tube body encloses an inner tube cavity; the outer peripheral wall of the inner tube body and the inner peripheral wall of the outer tube body are separated to form a fluid cavity; the balloon body comprises a proximal neck and a distal neck, the proximal neck is connected to the end of the outer tube body, and the distal neck is connected to the distal end of the inner tube body; the inner wall of the balloon body and the outer peripheral wall of the inner tube body enclose a balloon cavity; a connecting channel, one end of which is connected to an inner port of the channel and the other end is connected to an outer port of the channel, the cross-sectional area of ​​the connecting channel being smaller than the cross-sectional area of ​​the fluid cavity; and a limiting member arranged at the inner port of the channel. The balloon catheter provided by the present invention can not only ensure that no air is trapped, but also does not deteriorate the performance of the balloon body.

Description

Technical Field

[0001] The present invention relates to the technical field of medical devices, and in particular to a balloon catheter. Background Art

[0002] When air and contrast agent coexist in the balloon, the air cannot be visualized, resulting in a deviation between the balloon's appearance shape under X-rays and the actual balloon's filled shape. Therefore, clinically, balloons need to be deflated before use to expel the air in the balloon cavity and fluid cavity to prevent intraoperative gas from interfering with the balloon's filling effect.

[0003] Because the distal end of the balloon lumen is closed, completely evacuating the air from the balloon and fluid cavities is extremely difficult and time-consuming. Contrast agents are typically liquids, and air is lighter than liquids. Based on this characteristic, the prior art uses a repeated filling and aspiration process to perform the evacuation operation. For example, during aspiration, negative pressure is created within the balloon and fluid cavities. During inflation, the balloon is positioned downward, expanding, causing the contrast agent to flow downward and air from the balloon and fluid cavities to escape upward. Due to the small size of the fluid cavity and the influence of the liquid's surface tension, the air in the balloon and fluid cavities cannot completely escape upward, resulting in a time-consuming and labor-intensive operation. Even vibrating (or gently flicking) the balloon catheter has little effect. Furthermore, repeated filling and aspiration can cause wrinkles in the balloon, increasing the balloon's passable size, hindering subsequent clinical use, increasing the risks of instrument use, and increasing surgical time. Another way to vent air is to perform long-term continuous suction in order to achieve a vacuum state in the balloon cavity and expel all the air. This may cause adhesion between the folds of the balloon, resulting in failure to expand smoothly during clinical use.

[0004] For example, patent publication number CN112807553A discloses a balloon microcatheter comprising a catheter comprising a coaxial outer tube and inner tube. Ribs on the catheter separate the annular channel between the inner and outer tubes into a first filling chamber and a second filling chamber. A balloon is fixedly attached to the distal end of the catheter, and the inner chamber of the balloon communicates with both the first and second filling chambers. The two filling chambers are connected in a U-shaped design. When a contrast agent is infused into one filling channel, the other filling channel serves as an exhaust channel. However, this design also has some drawbacks. For example, the ribs between the inner and outer tubes reduce the catheter's flexibility, potentially preventing it from traversing tortuous blood vessels. Furthermore, since most balloon catheters are longer than one meter (110-170 cm), the ribs undoubtedly increase the production process and manufacturing costs. Patent document CN103648575A discloses a balloon catheter having one or more air-clearing paths at the interface between the inner tube and the distal portion of the balloon. These paths are highly permeable to gas and sealable to liquid. During use, the distal end of the balloon catheter is positioned higher than the proximal end, and then a balloon inflation medium, such as a contrast agent or saline solution, is injected through the proximal inflation port. When the inflation medium is filled, air is forced to flow out of the air-clearing paths. Due to the properties of air and water molecules, to achieve the function of being breathable and water-tight, the air-clearing paths need to be micron-sized, for example, 10 microns or less. Such a small size undoubtedly increases the difficulty of production. Patent publication number CN113648518A discloses a balloon catheter comprising an exhaust channel extending along the distal end of the balloon catheter and a purge port connected to the exhaust channel. The purge port comprises a membrane positioned proximal to the exhaust channel. The membrane selectively allows air to pass through while retaining liquid (the pore size of the membrane is approximately 0.4-0.6 microns). This allows air that passes through the membrane of the purge port to be transported and displaced outward through the exhaust channel, while preventing liquid from passing through. During use, the distal end of the balloon catheter is positioned higher than the proximal end, and an inflation medium, such as a contrast agent or saline solution, is then injected through the proximal inflation port. As the inflation medium fills the balloon, air is forced out through the air purge path.

[0005] However, on the one hand, the above solutions all squeeze out the remaining air in the balloon by injecting a contrast agent or saline solution from the proximal inflation port. Because the air removal path or membrane pore size is small and does not allow liquid to pass through, the balloon will inevitably need to be continuously pressurized during degassing, which may cause the balloon to be unable to fold into its original shape after depressurization. On the other hand, after the air is expelled, the balloon needs to be restored to its initial folded state before use, and accordingly, the contrast agent or saline solution in the balloon needs to be aspirated again. Because the air removal path or membrane allows air to pass through, air will inevitably be sucked into the balloon cavity through the air removal path or membrane. On the other hand, because the exhaust channel or membrane allows air to pass but does not allow liquid to pass through, this will inevitably result in the gas in the exhaust channel being unable to be discharged during the degassing process. Therefore, existing balloon catheters not only have difficulty in ensuring that there is no air remaining in the balloon, but also easily deteriorate the performance of the balloon. Summary of the Invention

[0006] In view of this, the present invention provides a balloon catheter to solve the problem that existing balloon catheters not only have difficulty in ensuring that there is no air residue in the balloon, but also that the gas in the exhaust channel of the balloon catheter with an exhaust channel cannot be discharged, and the performance of the balloon is easily deteriorated.

[0007] In a first aspect, the present invention provides a balloon catheter comprising:

[0008] The outer tube body has an inner peripheral wall enclosing an outer tube cavity;

[0009] The inner tube body is built into the outer tube cavity; the inner peripheral wall of the inner tube body encloses the inner tube cavity; the outer peripheral wall of the inner tube body and the inner peripheral wall of the outer tube body are separated to form a fluid cavity;

[0010] The balloon body includes a proximal neck and a distal neck, wherein the proximal neck is connected to the end of the outer tube body, and the distal neck is connected to the distal end of the inner tube body; the inner wall of the balloon body and the outer peripheral wall of the inner tube body enclose a balloon cavity;

[0011] a connecting channel, one end of which is connected to the inner channel port and the other end of which is connected to the outer channel port, wherein the cross-sectional area of ​​the connecting channel is smaller than the cross-sectional area of ​​the fluid cavity, wherein the inner channel port is disposed in the balloon cavity and the outer channel port is disposed outside the balloon cavity;

[0012] A limiting member is arranged at the port in the channel; when the pressure outside the balloon cavity is higher than the pressure inside the balloon cavity, the limiting member is suitable for unidirectionally opening the port in the channel under the action of the pressure difference, so as to only allow the fluid to flow into the balloon cavity through the connecting channel but not allow the fluid to flow out of the balloon cavity through the connecting channel; when the pressure inside the balloon cavity is higher than the pressure outside the balloon cavity, the limiting member is suitable for sealing the port in the channel under the action of the pressure difference, so as to prevent the fluid from flowing into or out of the balloon cavity through the connecting channel; when the balloon body is depressurized and folded to the initial state, the balloon body presses against the limiting member to prevent the fluid from flowing into the balloon cavity through the connecting channel.

[0013] In an optional embodiment, the limiting member includes a fixed portion and a folding portion, the fixed portion is fixedly arranged on the outer circumferential wall of the inner tube body or fixedly arranged on the inner circumferential wall of the balloon body, one side of the folding portion is connected to the fixed portion, and the other side is suitable for elastically folding relative to the fixed portion under the action of pressure difference to selectively connect the port in the channel with the balloon cavity.

[0014] In an optional embodiment, a connecting channel is opened on the inner tube body; one end of the connecting channel extends distally to the outside of the inner tube body and forms an external channel port, and the other end extends proximally to the inside of the balloon cavity and forms an internal channel port, which is suitable for communicating with the balloon cavity.

[0015] In an optional embodiment, the outer channel port is opened on the outer peripheral wall of the inner tube body; the outer channel port is arranged on the outer peripheral wall of the inner tube body near the distal neck;

[0016] Alternatively, the outer channel port is opened on the distal end surface of the inner tube body.

[0017] In an optional embodiment, a tube wall body is provided between the outer circumferential wall of the inner tube body and the inner circumferential wall of the balloon body, the outer circumferential wall of the tube wall body is fixedly connected to the distal neck, and a connecting channel is formed between the tube wall body and the inner tube body; one end of the connecting channel extends distally to the outside of the balloon cavity and forms an outer channel port, and the other end extends proximally to the inside of the balloon cavity and forms an inner channel port, and the inner channel port is suitable for communicating with the balloon cavity.

[0018] In an optional embodiment, the distal neck and the outer tube body are connected to form a first connecting portion, and a connecting channel is formed on the first connecting portion; one end of the connecting channel extends distally to the outside of the balloon cavity and forms an external channel port, and the other end extends proximally to the inside of the balloon cavity and forms an internal channel port, and the internal channel port is suitable for communicating with the balloon cavity.

[0019] In an optional embodiment, a connecting channel is opened on the balloon body, one end of the connecting channel extends to the outer circumferential wall of the balloon body and forms an outer channel port, and the other end extends to the inner circumferential wall of the balloon body and forms an inner channel port, which is suitable for communicating with the balloon cavity.

[0020] In an optional embodiment, the limiting member includes a fixing portion and a folding portion, the fixing portion being fixedly disposed on the inner peripheral wall of the balloon body, and the folding portion being adapted to selectively fit against the inner peripheral wall of the balloon body under the action of a pressure difference to selectively connect the port in the channel with the balloon cavity;

[0021] Alternatively, the fixing portion is fixedly arranged on the outer peripheral wall of the inner tube body, and the folded portion is suitable for selectively fitting with the inner peripheral wall of the balloon body under the action of pressure difference to selectively connect the port in the channel with the balloon cavity.

[0022] In an optional embodiment, the distal end of the balloon body is folded inward to form a second connecting portion; at least a portion of the second connecting portion is suitable for forming a distal neck, and the outer peripheral wall of the distal neck is fixedly connected to the distal outer peripheral wall of the inner tube body.

[0023] In an optional embodiment, the port in the channel is opened on the outer peripheral wall of the inner tube body, the distal end of the second connecting part is suitable for forming a distal neck, and the proximal end of the second connecting part is suitable for forming a limiting member, which is suitable for selectively sealing the port in the channel under the action of pressure difference.

[0024] In an optional embodiment, the port in the channel is arranged on the outer circumferential wall of the inner tube body; a limiting portion is provided on the inner circumferential wall of the balloon body, and the limiting portion is suitable for pressing against the limiting component when the balloon body contracts, so that the limiting component blocks the port in the channel.

[0025] In an optional embodiment, the limiting portion is directly formed by the inner peripheral wall of the balloon body protruding into the balloon cavity;

[0026] Alternatively, the limiting portion is formed by the outer peripheral wall of the balloon body being recessed toward the inner peripheral wall of the balloon body, so that the inner peripheral wall of the balloon body protrudes into the balloon cavity.

[0027] In an optional embodiment, a connecting channel is opened on the inner tube body, and the connecting channel is arranged through the inner tube body. One end of the connecting channel extends into the inner tube cavity and forms an external channel port, and the other end extends into the balloon cavity and forms an internal channel port. The internal channel port is suitable for communicating with the balloon cavity.

[0028] In an optional embodiment, the port in the channel is arranged on the outer circumferential wall of the inner tube body; the limiting member is beveled on the outer circumferential wall of the inner tube body at the port in the channel and forms a notch, and the notch is only connected to the port in the channel but not to the inner tube cavity; the limiting member includes a fixing portion and a folding portion, the fixing portion is connected to the outer circumferential wall of the inner tube body, and when the folding portion completely covers the port in the channel, the limiting member is completely embedded in the notch.

[0029] In an optional embodiment, the limiting member is obliquely cut from the outer peripheral wall of the inner tube body to the inner peripheral wall of the inner tube body to form a connecting channel; when the limiting member is completely in contact with the inner tube body, the connecting channel is completely closed.

[0030] In a second aspect, the present invention further provides a method for using the balloon catheter as described above, comprising:

[0031] Before use, the balloon body in the initial folded state is immersed in a contrast agent or saline solution; negative pressure is applied to the balloon cavity, so that the contrast agent or saline solution enters the balloon cavity through the connecting channel and continues to flow along the fluid cavity to the proximal end, completing the exhaust;

[0032] During use, contrast agent or saline solution is injected into the fluid cavity, so that positive pressure is formed in the balloon cavity and applied to the limiting member, so that the limiting member blocks the port in the channel, preventing the contrast agent or saline solution from overflowing out of the balloon cavity, thereby achieving filling of the balloon body;

[0033] After use, the pressure is released and contrast agent or saline solution is sucked toward the proximal end through the fluid cavity, causing the balloon body to be deflated.

[0034] In an optional embodiment, deflation of the balloon body further includes pressing the balloon body against a limiting member, so that the limiting member blocks and seals the port in the channel.

[0035] The balloon catheter provided by the present invention has the following beneficial effects:

[0036] The balloon catheter provided by the present invention is provided with a connecting channel. When the balloon catheter is vented before use, it is only necessary to apply negative pressure to the balloon cavity to allow the contrast agent or saline solution to enter the balloon cavity through the connecting channel. The balloon, which is already in a folded state, does not need to be inflated and expanded or repeatedly inflated and deflated, which is conducive to ensuring the performance of the balloon body.

[0037] Since the cross-sectional area of ​​the connecting channel is relatively small, under the action of liquid surface tension and capillary effect, when the outer end of the channel is placed in a contrast agent or saline solution, the contrast agent or saline solution will enter the connecting channel (the contact angle between the contrast agent or saline solution and the inner wall of the connecting channel is less than 90°);

[0038] At the same time, by providing the limiting member, when the balloon catheter is inflated during use, since the cross-sectional area of ​​the connecting channel is smaller than the cross-sectional area of ​​the fluid cavity, when contrast agent or saline solution is injected into the fluid cavity, a flow rate difference can be formed between the inside and outside of the balloon cavity (the flow rate entering the balloon cavity from the fluid cavity is greater than the flow rate flowing out of the balloon cavity from the connecting channel), thereby generating a positive pressure on the limiting member. The positive pressure prompts the limiting member to block the port in the channel, thereby preventing the contrast agent or saline solution from overflowing out of the balloon cavity, and achieving the balloon filling;

[0039] When the pressure is released after the balloon catheter is used, since the cross-sectional area of ​​the connecting channel is smaller than the cross-sectional area of ​​the fluid cavity, when the contrast agent or saline solution is sucked from the fluid cavity to the proximal end, the blood has not yet had time to enter the balloon cavity through the connecting channel (the flow rate of blood entering the balloon cavity from the connecting channel is smaller than the flow rate of the contrast agent or saline solution from the balloon cavity into the fluid cavity), and the balloon body is deflated. During the deflation process, the balloon body will press against the limiting component to prompt the limiting component to block the port in the channel (in this case, the pressure effect of the balloon body on the limiting component is greater than the pressure effect of the pressure difference between the inside and outside of the balloon cavity on the limiting component), preventing blood from being sucked into the balloon cavity and the fluid cavity, and the greater the pressure difference / flow difference, the more obvious the sealing effect.

[0040] Therefore, the balloon catheter provided by the present invention, first, by adopting a single suction and exhaust method, does not require filling the balloon body or repeatedly filling and suctioning the balloon body, and can completely exhaust the air in the balloon cavity and the fluid cavity. This is simple and fast, not only ensuring that there is no air residue, but also will not deteriorate the performance of the balloon body; secondly, in addition to being able to exhaust the air in the balloon cavity and the fluid cavity, the air in the connecting channel can also be exhausted, thereby truly achieving "zero air residue" of the air; thirdly, thanks to the fact that the balloon body does not need to be filled during the exhaust process, the balloon catheter provided by the present invention is not only suitable for non-compliant balloons and semi-compliant balloons, but also for compliant balloons. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the specific embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0042] Figure 1 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention;

[0043] Figure 2 for Figure 1 A schematic diagram of the working principle of a balloon catheter is shown;

[0044] Figure 3 This is a schematic structural diagram of another balloon catheter according to an embodiment of the present invention;

[0045] Figure 4 This is a schematic structural diagram of another balloon catheter according to an embodiment of the present invention;

[0046] Figure 5 This is a schematic structural diagram of another balloon catheter according to an embodiment of the present invention;

[0047] Figure 6 This is a schematic structural diagram of another balloon catheter according to an embodiment of the present invention;

[0048] Figure 7 for Figure 6 Schematic diagram of the cross-sectional structure of the AA section;

[0049] Figure 8 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention including multiple connecting channels;

[0050] Figure 9 for Figure 8 Schematic diagram of the cross-sectional structure of the middle BB section;

[0051] Figure 10 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention;

[0052] Figure 11 for Figure 10 Schematic diagram of the cross-sectional structure of the CC section;

[0053] Figure 12 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention;

[0054] Figure 13 for Figure 12 Schematic diagram of the cross-sectional structure of the middle DD section;

[0055] Figure 14 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention;

[0056] Figure 15 for Figure 14 Enlarged view of point E in the middle;

[0057] Figure 16 This is a schematic structural diagram of another balloon catheter according to an embodiment of the present invention;

[0058] Figure 17 for Figure 16 Enlarged view of point F in the middle;

[0059] Figure 18This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention when the port in the channel is closed;

[0060] Figure 19 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention when the port in the channel is opened;

[0061] Figure 20 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention;

[0062] Figure 21 This is a schematic structural diagram of another balloon catheter according to an embodiment of the present invention;

[0063] Figure 22 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention when the port in the channel is closed;

[0064] Figure 23 for Figure 22 The schematic diagram of the structure of the balloon catheter shown is when the port in the channel is opened;

[0065] Figure 24 for Figure 23 Enlarged view of point G in the middle;

[0066] Figure 25 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention;

[0067] Figure 26 for Figure 25 Enlarged view of point H in the middle;

[0068] Figure 27 This is a schematic structural diagram of a balloon catheter according to an embodiment of the present invention;

[0069] Figure 28 for Figure 27 The enlarged view of point I in the middle;

[0070] Figure 29 Schematic diagram of the structure of a Y-valve of a balloon catheter according to an embodiment of the present invention.

[0071] Description of reference numerals:

[0072] 10. Outer tube body;

[0073] 20. Inner tube body; 201. Inner tube lumen; 202. Fluid cavity; 203. Notch; 21. Distal end face;

[0074] 30. Balloon body; 301. Balloon cavity; 31. Proximal neck; 32. Distal neck; 321. First connecting portion; 322. Second connecting portion; 33. Position limiting portion;

[0075] 40, connecting channel; 401, port inside the channel; 402, port outside the channel;

[0076] 50. Restriction member; 51. Fixing portion; 52. Folding portion;

[0077] 60. Tube wall;

[0078] 70. Y-valve; 71. First cavity; 72. Second cavity. DETAILED DESCRIPTION

[0079] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative efforts shall fall within the scope of protection of the present invention.

[0080] The following combination Figures 1 to 29 , describing embodiments of the present invention.

[0081] According to an embodiment of the present invention, on the one hand, a balloon catheter is provided, comprising:

[0082] The outer tube body 10 has an inner peripheral wall enclosing an outer tube cavity;

[0083] The inner tube body 20 is built into the outer tube cavity; the inner peripheral wall of the inner tube body 20 encloses an inner tube cavity 201; the outer peripheral wall of the inner tube body 20 and the inner peripheral wall of the outer tube body 10 are separated to form a fluid cavity 202;

[0084] The balloon body 30 includes a proximal neck 31 and a distal neck 32. The proximal neck 31 is connected to the distal end of the outer tube body 10, and the distal neck 32 is connected to the distal end of the inner tube body 20. The "distal end" of the inner tube body 20 includes the distal end and the proximal section of the distal end of the inner tube body 20. The inner wall of the balloon body 30 and the outer peripheral wall of the inner tube body 20 enclose a balloon cavity 301.

[0085] A connecting channel 40, one end of which is connected to the inner channel port 401 and the other end of which is connected to the outer channel port 402. The cross-sectional area of ​​the connecting channel 40 is smaller than the cross-sectional area of ​​the fluid cavity 202, so as to form a pressure difference between the inside and outside of the balloon cavity 301 during the suction process. The inner channel port 401 is disposed inside the balloon cavity 301, and the outer channel port 402 is disposed outside the balloon cavity 301.

[0086] The limiting member 50 is arranged at the port 401 in the channel; when the pressure outside the balloon cavity 301 is higher than the pressure inside the balloon cavity 301, the limiting member 50 is suitable for unidirectionally opening the port 401 in the channel under the action of the pressure difference, so as to only allow the fluid to flow into the balloon cavity 301 through the connecting channel 40 but not allow the fluid to flow out of the balloon cavity 301 through the connecting channel 40; when the pressure inside the balloon cavity 301 is higher than the pressure outside the balloon cavity 301, the limiting member 50 is suitable for sealing the port 401 in the channel under the action of the pressure difference, so as to prevent the fluid from flowing into or out of the balloon cavity 301 through the connecting channel 40; when the balloon body 30 is depressurized and folded to the initial state, the balloon body 30 presses against the limiting member 50 (in this case, the pressing effect of the balloon body 30 on the limiting member 50 is greater than the effect of the pressure difference between the inside and outside of the balloon cavity 301) to prevent the fluid from flowing into the balloon cavity 301 through the connecting channel 40.

[0087] It should be noted that, for easier understanding, the terms "proximal" and "distal" are defined from the perspective of a physician (or other surgeon). Therefore, the term "proximal" refers to the side or end of the device closest to the external body wall and / or the surgeon, or the portion thereof, while the term "distal" refers to the side or end of the device in the direction opposite to the external body wall and / or the surgeon. The balloon body 30 is initially folded.

[0088] The balloon catheter provided in this embodiment is provided with a connecting channel 40. When the balloon catheter is vented before use, it is only necessary to apply a (relatively low) negative pressure to the balloon cavity 301 to allow the contrast agent or saline solution to enter the balloon cavity 301 through the connecting channel 40. The balloon body 30, which is already in a folded state, does not need to be inflated and expanded or repeatedly inflated and pumped, which is beneficial to ensuring the performance of the balloon body 30. Since the cross-sectional area of ​​the connecting channel 40 is relatively small, under the action of the liquid surface tension and the capillary effect, when the channel is folded, the contrast agent or saline solution can enter the balloon cavity 301. When the outer port is placed in a contrast agent or saline solution, the contrast agent or saline solution will enter the connecting channel (the contact angle between the contrast agent or saline solution and the inner wall of the connecting channel is less than 90 degrees); at the same time, by providing a limiting member 50, when the balloon catheter is filled in use, since the cross-sectional area of ​​the connecting channel 40 is smaller than the cross-sectional area of ​​the fluid cavity 202, when the contrast agent or saline solution is injected into the fluid cavity 202, a flow difference can be formed between the inside and outside of the balloon cavity 301 (the flow rate entering the balloon cavity from the fluid cavity is greater than the flow rate flowing out of the balloon cavity from the connecting channel), so as to prevent the flow of contrast agent or saline solution from flowing out of the balloon cavity from the connecting channel. Positive pressure is formed on the limiting member 50, which prompts the limiting member 50 to block the port 401 in the channel, thereby preventing the contrast agent or saline solution from overflowing out of the balloon cavity 301, thereby achieving the filling of the balloon; when the balloon catheter is depressurized after use, since the cross-sectional area of ​​the connecting channel 40 is smaller than the cross-sectional area of ​​the fluid cavity 202, when the contrast agent or saline solution is sucked from the fluid cavity 202 to the proximal end, blood has not yet entered the balloon cavity 301 through the connecting channel 40 (the flow rate of blood entering the balloon cavity 301 from the connecting channel 40 is smaller than that of the positive pressure). The balloon body 30 is deflated when the contrast agent or saline solution flows from the balloon cavity 301 into the fluid cavity 202. During the deflation process, the balloon body 30 presses against the limiting member 50 to prompt the limiting member 50 to seal the port 401 in the channel (in this case, the pressing effect of the balloon body 30 on the limiting member 50 is greater than the pressing effect of the pressure difference between the inside and outside of the balloon cavity 301 on the limiting member 50), preventing blood from being sucked into the balloon cavity 301 and the fluid cavity 202. The greater the pressure difference / flow difference, the more obvious the sealing effect.

[0089] Therefore, the balloon catheter provided in this embodiment, first, adopts a single suction and exhaust method, without filling the balloon body 30 or repeatedly filling and suctioning the balloon body 30, and can completely exhaust the air in the balloon cavity 301 and the fluid cavity 202. This is simple and fast, not only ensuring that there is no air residue, but also without deteriorating the performance of the balloon body 30; secondly, in addition to exhausting the air in the balloon cavity 301 and the fluid cavity 202, the air in the connecting channel 40 can also be discharged together, thereby truly achieving "zero air residue" of the air; thirdly, thanks to the fact that the balloon body 30 does not need to be filled during the exhaust process, the balloon catheter provided by the present invention is not only suitable for non-compliant balloons and semi-compliant balloons, but also for compliant balloons.

[0090] Furthermore, the distal end of the balloon catheter is positioned lower than the proximal end and is immersed in a contrast agent or saline solution for exhaust. For example, when the contrast agent or saline solution fills the balloon cavity 301 and the fluid cavity 202, the air is exhausted visibly, which is convenient for judgment.

[0091] Furthermore, a radiopaque marker is provided on the inner tube body 20 at the distal end of the inner tube body 20 and / or at both ends of the effective length of the balloon body 30. The radiopaque marker is made of an X-ray opaque metal material such as a platinum-iridium alloy or a polymer containing X-ray opaque particles. The radiopaque marker can be ring-shaped or C-shaped and is fixed to the outer circumferential wall of the inner tube body 20 or embedded in the inner circumferential wall of the inner tube body 20.

[0092] It should be noted that the structure of the connecting channel 40 can be a straight cylinder, a spiral channel formed by spirally winding around the axis of the inner tube body 20, or an S-shaped channel that spirals along the circumference of the tube wall of the inner tube body 20; the cross-section of the connecting channel 40 can be circular, elliptical, flat, or an optional arc shape, which can be adjusted according to actual usage and is not specifically limited in this embodiment.

[0093] Furthermore, the diameter of the equivalent circle of the cross section of the connecting channel 40 is D, and D is sufficient to allow contrast agent or saline solution to flow through. For example, D can be selected as 10 microns ≤ D ≤ 10000 microns, further selected as 10 microns ≤ D ≤ 5000 microns, and more preferably 10 microns ≤ D ≤ 1000 microns. The specific selection can be made based on the size of the inner tube body 20 and / or the balloon body 30.

[0094] In this embodiment, on the one hand, since the fluid (including gas and liquid) has a certain viscosity, if the diameter D of the equivalent circle of the cross section of the connecting channel 40 is too small, it is easy to cause the fluid (especially the contrast agent) to block the connecting channel 40, making it difficult for the fluid to enter the fluid cavity 202 and the balloon cavity 301 through the connecting channel 40. Therefore, the diameter D of the equivalent circle of the cross section of the connecting channel 40 must meet the flow of fluid, for example, D ≥ 10 microns; on the other hand, due to the size structure limitations of the inner tube body 20 and the balloon body 30, the diameter D of the equivalent circle of the cross section of the connecting channel 40 cannot be too large, and the cross-sectional area of ​​the connecting channel 40 must be smaller than the cross-sectional area of ​​the fluid cavity 202. Therefore, the diameter D of the equivalent circle of the cross section of the connecting channel 40 must also meet the requirement of D ≤ 10,000 microns. In the balloon catheter provided in this embodiment, the diameter D of the equivalent circle of the cross section of the connecting channel 40 is more preferably 10 microns ≤ D ≤ 1000 microns, thereby avoiding fluid blockage of the connecting channel 40 while ensuring the normal design size and normal operation of the inner tube body 20 and the balloon body 30, and ensuring that the fluid can flow smoothly through the connecting channel 40 and enter the fluid cavity 202 and the balloon cavity 301 during operation.

[0095] It is worth noting that the cross-sectional size of the connecting channel 40 of the balloon catheter provided in this embodiment is larger than the channel in the prior art that only allows gas to pass but not liquid to pass through. This can not only shorten the exhaust time before use, but also reduce the production difficulty and simplify the production process.

[0096] Furthermore, the cross-sectional area of ​​the connecting channel 40 is W, and W satisfies 1 / 35·S≤W≤1 / 10·S, where S is the cross-sectional area of ​​the fluid cavity 202 .

[0097] In this embodiment, the cross-sectional area of ​​the connecting channel 40 needs to be smaller than the cross-sectional area of ​​the fluid cavity 202. The cross-sectional area of ​​the fluid cavity 202 is usually a predetermined design value. However, if the cross-sectional area of ​​the connecting channel 40 is too small, it is easy to cause the fluid to block the connecting channel 40, making it difficult for the fluid to enter the fluid cavity 202 and the balloon cavity 301 through the connecting channel 40. Therefore, the cross-sectional area size W of the connecting channel 40 needs to satisfy W≥1 / 35·S; at the same time, the difference between the cross-sectional area of ​​the connecting channel 40 and the cross-sectional area of ​​the fluid cavity 202 cannot be too small, that is, under the premise that the cross-sectional area of ​​the fluid cavity 202 is determined, the cross-sectional area of ​​the connecting channel 40 cannot be too large, otherwise it will be difficult to form a sufficient pressure difference / flow difference between the inside and outside of the balloon cavity 301 during the suction process, and the balloon body 30 cannot be quickly deflated. Therefore, the cross-sectional area size W of the connecting channel 40 also needs to satisfy W≤1 / 10·S. The cross-sectional area W of the balloon catheter provided in this embodiment satisfies 1 / 35·S≤W≤1 / 10·S, which can not only prevent the fluid from clogging the connecting channel 40 and ensure that the fluid smoothly enters the fluid cavity 202 and the balloon cavity 301 through the connecting channel 40, but also ensure that a sufficient pressure difference / flow difference is formed inside and outside the balloon cavity 301, thereby causing the balloon body 30 to deflate quickly.

[0098] In this embodiment, the inner wall of the connecting channel 40 may be provided with a coating, for example, to increase the coating wetted by the contrast agent or saline solution to reduce the contact angle between the contrast agent or saline solution and the inner wall of the connecting channel 40 .

[0099] It should be noted that the materials, dimensions, and other parameters of the outer tube body 10, inner tube body 20, and balloon body 30 in this embodiment can be adjusted based on actual usage and are not specifically limited in this embodiment. The connection between the proximal neck 31 and the distal end of the outer tube body 10, and the connection between the distal neck 32 and the distal end of the inner tube body 20, can be achieved through welding, melting, gluing, or other polymeric or non-polymeric methods, or a combination thereof. The specific connection method between the balloon body 30 and the outer tube body 10 and inner tube body 20 can be adjusted based on actual usage and is not specifically limited in this embodiment.

[0100] It should be noted that when the balloon catheter provided in this embodiment is used for intracranial interventional treatment, the outer diameter of the outer tube body 10 can be 0.025 inches to 0.050 inches, for example, 0.025 inches to 0.045 inches, or 0.036 inches to 0.045 inches; and the wall thickness of the outer tube can be 0.0001 inches to 0.0050 inches, for example, 0.001 inches to 0.0045 inches, or 0.002 inches to 0.0040 inches. The outer tube body 10 is made of an elastic material to maintain its shape. Specifically, the material of the outer tube body 10 can include polyamide resin, polyester resin, polyurethane resin, polyolefin resin, fluorine-containing resin, vinyl chloride resin, silicone resin, natural rubber, synthetic rubber, etc. These materials can be used alone or in combination of two or more. The resin can be either a thermoplastic resin or a thermosetting resin, with thermoplastic resin being preferred. The outer tube body 10 can be configured with a gradually decreasing hardness from the proximal end to the distal end (in a segmented manner, with multiple ends connected together through heat shrinkage and / or reflow processes). For example, if the outer tube body 10 is made of resin, the proximal end can be made of a higher-hardness material and the distal end of a lower-hardness material. Alternatively, the proximal and distal ends can be made of the same material but with different grades, such as a higher-hardness proximal end (Shore hardness 65D-75D) and a lower-hardness distal end (Shore hardness 40D-55D). The specific configuration of the outer tube body 10 can be adjusted based on actual usage and is not specifically limited in this embodiment.

[0101] It should be noted that when the balloon catheter provided in this embodiment is used for intracranial interventional treatment, the outer diameter of the inner tube body 20 can be 0.016 inches to 0.040 inches, for example, 0.016 inches to 0.035 inches, or another example, 0.026 inches to 0.035 inches; the inner diameter of the inner tube body 20 can be 0.010 inches to 0.040 inches, for example, 0.015 inches to 0.040 inches, or another example, 0.021 inches to 0.035 inches. The inner tube body 20 includes an inner tube, an outer tube, and a reinforcement layer therebetween. It will be understood by those skilled in the art that both the inner tube and the outer tube can be made of various materials and structures that have the property of being able to bend along blood vessels, for example, at least one and / or a combination of multiple of polyamide, vinyl chloride, polyurethane, polyimide, polyethylene, polyester elastomer, polypropylene, polytetrafluoroethylene, polyetheretherketone, and polyvinylidene fluoride. Specifically, the reinforcement layer can utilize a spiral structure of wound metal wire, a braided mesh structure, or a combination thereof. The metal wire can be made of stainless steel, platinum, nickel, cobalt, chromium, titanium, tungsten, gold, Ni-Ti alloy, Co-Cr alloy, or combinations thereof. The density of the reinforcement layer gradually decreases from the proximal end to the distal end. This can be achieved by adjusting the helical angle (the angle between the helical plane and the inner tube axis, expressed as an acute angle), the pitch of the helical structure, or the braiding density of the mesh structure. The specific configuration of the inner tube body 20 can be adjusted based on actual usage and is not specifically limited in this embodiment.

[0102] It should be noted that when the balloon catheter provided in this embodiment is used for intracranial interventional treatment, the wall thickness of the balloon body 30 can be between 20 microns and 5000 microns, for example, between 100 microns and 5000 microns, or between 200 microns and 1000 microns. The balloon body 30 can be made of a non-compliant material, or a compliant material, or a material between compliance and non-compliance. The materials for preparing the balloon body 30 specifically include: for example, polyolefin resins, such as polyethylene, polypropylene, and ethylene-propylene copolymers; polyester resins, such as polyethylene terephthalate and polyester elastomers; polyurethane resins; polyamide resins; fluororesins; silicone resins; natural rubber; synthetic rubber, etc. The specific configuration of the balloon body 30 can be adjusted according to actual usage conditions and is not specifically limited in this embodiment.

[0103] It should be noted that to improve the compliance of the balloon segment, the helical structure in the overlapping section of the inner tube body 20 and the balloon body 30 has a smaller helical angle or a larger pitch than in other sections, or the mesh structure has a lower weave density than in other sections. For example, the helical angle in the overlapping section is less than 60° or less than 45°, while the helical angle in other sections is greater than 45° or greater than 60°. The helical pitch in the overlapping section is 0.0015-0.0060 inches, while that in other sections is 0.001-0.004 inches. The weave density in the overlapping section is 30-90 PPI, while that in other sections is 60-120 PPI. The metal wire can be round or flat. The diameter of the round wire is 0.0005-0.003 inches. The thickness of the flat wire is 0.0005-0.0025 inches, and the width is 0.001-0.005 inches.

[0104] It should be noted that when the balloon catheter provided by the present invention is used for coronary artery and valve interventional treatment, the outer diameter of the outer tube body 10, the outer diameter of the inner tube body 20, the wall thickness of the balloon body 30 and the spiral angle in the spiral structure of the inner tube body 20 can be adjusted according to actual passing conditions.

[0105] In some embodiments, the limiting member 50 includes a fixing portion 51 and a folding portion 52. The fixing portion 51 is fixedly arranged on the outer circumferential wall of the inner tube body 20 or fixedly arranged on the inner circumferential wall of the balloon body 30. One side of the folding portion 52 is connected to the fixing portion 51, and the other side is suitable for elastically folding relative to the fixing portion 51 under the action of pressure difference to selectively connect the port 401 in the channel with the balloon cavity 301.

[0106] When the pressure outside the balloon cavity 301 is higher than the pressure inside the balloon cavity 301, the pressure difference forces the folded portion 52 to move away from the channel port 401, thereby opening the channel port 401 and allowing fluid to enter the balloon cavity 301; when the pressure inside the balloon cavity 301 is higher than the pressure outside the balloon cavity 301, the pressure difference forces the folded portion 52 to fit tightly against the channel port 401, thereby blocking the channel port 401 and preventing the fluid from flowing out of the balloon cavity 301.

[0107] It should be noted that the restricting member 50 can preferably be a polymer film or polymer spring sheet with a certain degree of toughness, and the shape of the restricting member 50 can be adjusted based on the location at which the restricting member 50 is connected. The restricting member 50 can be connected to the outer circumferential wall of the inner tube body 20 or the inner circumferential wall of the balloon body 30 near the intra-channel port 401 by welding, melting, gluing, or other polymeric or non-polymeric methods, or a combination thereof, and covers the intra-channel port 401. It should be noted that the restricting member 50 covers the intra-channel port 401, but does not necessarily block it. The restricting member 50 can block the intra-channel port 401 under the action of a pressure differential. The restricting member 50 has elasticity that allows it to deform perpendicular to its axial direction. When one end is fixed, the other end can elastically deform away from its axis.

[0108] In some embodiments, see Figures 1-9 As shown, the connecting channel 40 is opened on the inner tube body 20, and the cross-sectional width of the connecting channel 40 is smaller than the wall thickness of the inner tube body 20; one end of the connecting channel 40 extends distally to the outside of the inner tube body 20 and forms an outer channel port 402, and the other end extends proximally to the inside of the balloon cavity 301 and forms an inner channel port 401, which is suitable for being connected to the balloon cavity 301.

[0109] In some embodiments, see Figure 2 As shown, the fixing portion 51 of the limiting member 50 is disposed on a side of the inner channel port 401 close to the proximal end.

[0110] In some embodiments, see Figure 3 As shown, the fixing portion 51 of the limiting member 50 is disposed on a side of the in-channel port 401 close to the distal end.

[0111] In some embodiments, see Figure 4 As shown, the limiting member 50 and the port 401 in the channel are on the same cross-section perpendicular to the axial direction. The limiting member 50 has an arc along the circumferential direction of the outer peripheral wall of the inner tube body 20 and semi-surrounds the outer peripheral wall of the inner tube body 20. The portion of the limiting member 50 corresponding to the port 401 in the channel is suitable for selectively blocking the port 401 in the channel, and the remaining portion is at least partially connected to the outer peripheral wall of the inner tube body 20.

[0112] In some embodiments, see Figure 5 As shown, the outer channel port 402 is opened on the outer peripheral wall of the inner tube body 20; the outer channel port 402 is set on the outer peripheral wall of the inner tube body 20 near the distal neck 32, thereby shortening the opening length of the connecting channel 40;

[0113] Alternatively, see Figure 6 and Figure 7As shown, the outer channel port 402 is opened on the distal end surface 21 of the inner tube body 20 , thereby reducing the complexity of the setting of the connecting channel 40 .

[0114] In some embodiments, see Figure 8 and Figure 9 As shown, the number of connecting channels 40 can also be two or more.

[0115] Furthermore, the connection channel 40 is provided by: the distal end of the inner tube body 20 is formed of a double-layer material, and the materials are connected together by welding, melting, gluing, or other polymeric / non-polymeric methods or a combination thereof; before the connection, a thread is pre-placed between the double-layer materials, and the thread is preferably made of metal. The middle section of the thread is embedded between the double-layer materials. The ends of the thread are exposed from the tube wall of the inner tube body 20 according to the above-mentioned different embodiments; after the double-layer materials are connected, the thread is removed to form the connection channel 40. Specifically, the materials of the double-layer materials can be the same or different. For example, the materials of the double-layer materials can be both polyether block polyamide resins, or the materials of the double-layer materials can be fluorine-containing resins for the inner layer and polyether block polyamide resins for the outer layer. The wall thicknesses of the double-layer materials can be the same or different.

[0116] In some embodiments, please combine Figure 10 and Figure 11 As shown, a tube wall body 60 is provided between the outer circumferential wall of the inner tube body 20 and the inner circumferential wall of the balloon body 30, the outer circumferential wall of the tube wall body 60 is fixedly connected to the distal neck 32, and a connecting channel 40 is formed between the tube wall body 60 and the inner tube body 20; one end of the connecting channel 40 extends distally to the outside of the balloon cavity 301 and forms an outer channel port 402, and the other end extends proximally to the inside of the balloon cavity 301 and forms an inner channel port 401, and the inner channel port 401 is suitable for being connected to the balloon cavity 301.

[0117] Preferably, the tube wall body 60 is disposed between the outer peripheral wall of the inner tube body 20 and the inner peripheral wall of the distal neck 32 .

[0118] Furthermore, the connection channel 40 is provided by connecting a tubular object to the outer wall surface of the inner tube body 20 by welding, melting, gluing or other polymeric or non-polymeric methods or a combination thereof, see Figure 11 As shown, the connection portion is smoothed if necessary; the distal neck 32 is connected to the inner tube body 20 and the circumferential outer surface of the tubular object.

[0119] In some embodiments, please combine Figure 12 and Figure 13As shown, the distal neck 32 and the outer tube body 10 are connected to form a first connecting portion 321, and a connecting channel 40 is formed on the first connecting portion 321; one end of the connecting channel 40 extends distally to the outside of the balloon cavity 301 and forms an external channel port 402, and the other end extends proximally to the inside of the balloon cavity 301 and forms an internal channel port 401, and the internal channel port 401 is suitable for being connected to the balloon cavity 301.

[0120] It should be noted that, in this embodiment, see Figure 12 As shown, the limiting member 50 is disposed near the distal neck portion 32 of the balloon body 30. Specifically, the fixing portion 51 of the limiting member 50 can be disposed on the inner circumferential wall of the balloon body 30 or on the outer circumferential wall of the inner tube body 20; preferably, the fixing portion 51 of the limiting member 50 is fixedly disposed on the outer circumferential wall of the inner tube body 20.

[0121] Furthermore, the setting method of the connecting channel 40 can be: before connecting the inner tube body 20 and the balloon body 30, a thread is preset between the distal neck 32 of the inner tube body 20 and the balloon body 30. After completing the connection between the inner tube body 20 and the balloon body 30, the thread is pulled out to form the connecting channel 40.

[0122] Furthermore, the setting method of the connecting channel 40 can also be: before connecting the inner tube body 20 and the balloon body 30, a wire is preset between the inner tube body 20 and the distal neck 32 of the balloon body 30, and the wire is a metal wire. The wire is heated so that the wire is at least partially embedded in the tube wall of the inner tube body 20, and then the inner tube body 20 and the balloon body 30 are connected, and finally the wire is pulled out to form the connecting channel 40.

[0123] In some embodiments, please combine Figure 14-17 As shown, the connecting channel 40 is opened on the balloon body 30, one end of the connecting channel 40 extends to the outer peripheral wall of the balloon body 30 and forms an outer channel port 402, and the other end extends to the inner peripheral wall of the balloon body 30 and forms an inner channel port 401, which is suitable for communicating with the balloon cavity 301.

[0124] Furthermore, the connection channel 40 is provided by opening the connection channel 40 on the balloon wall of the balloon body 30 by melting, puncturing, or the like.

[0125] Furthermore, the connecting channel 40 is opened at a position close to the distal end of the balloon body 30 .

[0126] Preferably, the connecting channel 40 is opened at the distal shoulder position of the balloon body 30.

[0127] In some embodiments, the limiting member 50 includes a fixing portion 51 and a folding portion 52. Figure 15 As shown, the fixing portion 51 is fixedly disposed on the inner peripheral wall of the balloon body 30, and the folded portion 52 is adapted to selectively fit with the inner peripheral wall of the balloon body 30 under the action of a pressure difference, so as to selectively connect the channel inner port 401 with the balloon cavity 301;

[0128] Alternatively, see Figure 17 As shown, the fixing portion 51 is fixedly arranged on the outer peripheral wall of the inner tube body 20, and the folded portion 52 is suitable for selectively fitting with the inner peripheral wall of the balloon body 30 under the action of pressure difference to selectively connect the channel port 401 with the balloon cavity 301.

[0129] In some embodiments, see Figure 18 and Figure 19 As shown, the distal end of the balloon body 30 is folded inward to form a second connecting portion 322; at least a portion of the second connecting portion 322 is suitable for forming a distal neck 32, and the outer peripheral wall of the distal neck 32 is fixedly connected to the distal outer peripheral wall of the inner tube body 20.

[0130] In some embodiments, see Figure 18 and Figure 19 As shown, the port 401 in the channel is opened on the outer peripheral wall of the inner tube body 20, the distal end of the second connecting portion 322 is suitable for forming the distal neck 32, and the proximal end of the second connecting portion 322 is suitable for forming a limiting member 50, which is suitable for selectively covering the port 401 in the channel under the action of pressure difference.

[0131] Furthermore, the connecting channel 40 can be opened on the inner tube body 20, wherein the outer channel port 402 can be opened on the distal end face 21 of the inner tube body 20, and the outer channel port 402 can also be opened on the outer peripheral wall of the inner tube body 20; the connecting channel 40 can also be arranged between the inner tube body 20 and the distal neck 32 of the balloon body 30.

[0132] In some embodiments, please combine Figure 20 and Figure 21 As shown, the port 401 in the channel is arranged on the outer peripheral wall of the inner tube body 20; a limiting portion 33 is provided on the inner peripheral wall of the balloon body 30, and the limiting portion 33 is suitable for pressing against the limiting member 50 when the balloon body 30 contracts, so that the limiting member 50 blocks the port 401 in the channel.

[0133] Furthermore, the limiting portion 33 can be circumferentially arranged around the inner circumferential wall of the balloon body 30 , or can be partially circumferentially arranged on the inner circumferential wall of the balloon body 30 .

[0134] In some embodiments, see Figure 20As shown, the limiting portion 33 is directly formed by the inner peripheral wall of the balloon body 30 protruding into the balloon cavity 301;

[0135] Alternatively, see Figure 21 As shown, the limiting portion 33 is formed by the outer peripheral wall of the balloon body 30 being recessed toward the inner peripheral wall of the balloon body 30 , so that the inner peripheral wall of the balloon body 30 protrudes into the balloon cavity 301 .

[0136] In this embodiment, by providing a limiting portion 33 on the inner circumferential wall of the balloon body 30, when the balloon body 30 needs to relieve pressure, negative pressure or high-flow suction is quickly applied to the balloon body 30. Since the cross-sectional area of ​​the connecting channel 40 is smaller than the cross-sectional area of ​​the fluid cavity 202, a pressure difference / flow difference between the inside and outside of the balloon cavity 301 is formed. This pressure difference / flow difference causes the balloon body 30 to contract. During the contraction of the balloon body 30, the limiting portion 33 presses against the limiting member 50, causing the limiting member 50 to block the port 401 in the channel. The greater the pressure difference, the better the blocking effect. In this way, the pressure of the balloon body 30 is relieved, facilitating the withdrawal of the balloon catheter from the body. It should be noted that in this case, the pressing effect of the balloon body 30 or the limiting portion 33 on the limiting member 50 is greater than the effect of the pressure difference between the inside and outside of the balloon cavity 301.

[0137] In some embodiments, see Figure 25-26 As shown, the connecting channel 40 is opened on the inner tube body 20, and the connecting channel 40 is set through the inner tube body 20. One end of the connecting channel 40 extends into the inner tube cavity 201 and forms an outer channel port 402, and the other end extends into the balloon cavity 301 and forms an inner channel port 401. The inner channel port 401 is suitable for being connected to the balloon cavity 301, thereby further shortening the length of the connecting channel 40.

[0138] Furthermore, the connecting channel 40 can be provided by directly forming the connecting channel 40 through physical drilling or chemical etching on the wall of the inner tube body 20, and then providing a restricting member 50 on the surface of the inner port 401. The specific configuration of the restricting member 50 can be any of the structural forms described in the above-mentioned embodiments. The connecting channel 40 can also be provided by first beveling the outer peripheral surface of the inner tube body 20 (the beveling direction is not limited) to form the restricting member 50, and then forming the connecting channel 40 through physical drilling or chemical etching on the beveled inner tube wall.

[0139] Furthermore, the outer channel port 402 is preferably disposed toward the distal end of the balloon catheter.

[0140] In some embodiments, see Figure 22-26As shown, the channel port 401 is arranged on the outer peripheral wall of the inner tube body 20; the limiting member 50 is beveled at the channel port 401 on the outer peripheral wall surface of the inner tube body 20 and forms a notch 203, and the notch 203 does not extend into the inner tube cavity 201; the limiting member 50 includes a fixing portion 51 and a folding portion 52, and the fixing portion 51 is connected to the outer peripheral wall of the inner tube body 20. When the folding portion 52 completely covers the channel port 401, the limiting member 50 is completely built into the notch 203, thereby reducing the outer diameter of the balloon body 30 after folding.

[0141] It should be noted that the channel outer port 402 may also be provided on the distal end surface 21 of the inner tube body 20 , or on the outer peripheral wall of the inner tube body 20 .

[0142] Furthermore, the setting method of the connecting channel 40 can be: the distal end of the inner tube body 20 is a double-layer material, and the double-layer material is connected together by welding, melting, gluing or other polymer / non-polymer methods or a combination thereof. Before the connection, a wire is pre-set between the double-layer materials. The wire is preferably made of metal. The middle section of the wire and the end close to the balloon body 30 are buried between the double-layer materials. After the double-layer materials are connected, the wire is pulled out to form a channel with one end in a sealed state (the end close to the balloon body 30 is sealed), and then the outer peripheral wall surface of the inner tube body 20 is beveled near the sealed end of the connecting channel 40 to cut the channel to form a port 401 in the channel.

[0143] In some embodiments, see Figure 27 and Figure 28 As shown, the outer peripheral wall of the inner tube body 20 is beveled and extends through the inner peripheral wall of the inner tube body 20, forming both the limiting member 50 and the connecting channel 40. When the limiting member 50 is fully in contact with the inner tube body 20, the connecting channel 40 is completely sealed. In this embodiment, the connecting channel 40 is formed by the inner tube body 20 wall at the cut surface and the beveled portion, eliminating the need for a separate connecting channel 40.

[0144] In some embodiments, see Figure 29 As shown, the balloon catheter further includes a Y-valve 70 , which includes a first lumen 71 and a second lumen 72 . The first lumen 71 is adapted to communicate with the inner lumen 201 , and the second lumen 72 is adapted to communicate with the fluid lumen 202 .

[0145] According to an embodiment of the present invention, on the other hand, a method for using the balloon catheter as described above is also provided, comprising:

[0146] Before use, the balloon body 30 in the initial folded state is evacuated by immersing it in a contrast agent or saline solution. Negative pressure (slow suction) is applied to the balloon cavity 301, so that the contrast agent or saline solution enters the balloon cavity 301 through the connecting channel 40 and continues to flow along the fluid cavity 202 to the proximal end, completing the evacuation.

[0147] During use, contrast agent or saline solution is injected into the fluid cavity 202. Due to the flow difference, positive pressure is generated on the limiting member 50, so that the limiting member 50 blocks the port 401 in the channel, preventing the contrast agent or saline solution from overflowing out of the balloon cavity 301, thereby achieving filling of the balloon body 30.

[0148] After use, the pressure is released and the contrast agent or saline solution is quickly sucked proximally through the fluid lumen 202 (compared to the slow suction of exhaust before use) to deflate the balloon body 30 .

[0149] In some embodiments, deflated the balloon body 30 further includes pressing the balloon body 30 against the restriction member 50 , so that the restriction member 50 blocks and seals the port 401 in the channel.

[0150] The following is a unified description of how to use a balloon catheter in conjunction with a Y-valve, where the Y-valve is located at the proximal end of the balloon catheter:

[0151] Exhaust before use: The balloon body 30 is in a folded state before use. The balloon body 30 is immersed in a contrast agent or saline solution. Preferably, the distal end of the balloon catheter is positioned lower than the proximal Y-valve 70. A syringe can be used to apply negative pressure (slow suction) to the balloon body 30 through the second lumen 72. The negative pressure does not need to be too large. It only needs to have a negative pressure effect and be able to suck the contrast agent or saline solution into the balloon cavity 301. The balloon body 30, which is already in a folded state, will not be further deformed. The contrast agent or saline solution enters the balloon cavity 301 through the connecting channel 40 and continues to flow along the fluid cavity 202 to the second lumen 72. The valve is closed or the piston of the syringe is fixed to avoid the flow of the contrast agent or saline solution. Because the cross-sectional area of ​​the connecting channel 40 is relatively small, under the action of the surface tension of the liquid, the contrast agent or saline solution will not flow out of the balloon cavity 301 from the connecting channel 40.

[0152] Filling during use: The contrast agent or saline solution stored in the syringe can be directly injected into the fluid cavity 202 through the second lumen 72; because the connecting channel 40 is smaller than the cross-sectional area of ​​the fluid cavity 202, when the contrast agent or saline solution is injected into the fluid cavity 202, a flow difference will be formed between the fluid cavity 202 and the connecting channel 40, thereby forming a positive pressure in the balloon cavity 301, and the positive pressure will be applied to the limiting member 50, so that the limiting member 50 blocks the port 401 in the channel, thereby preventing the contrast agent or saline solution from overflowing out of the balloon cavity 301, thereby achieving filling of the balloon body 30.

[0153] Pressure relief after use: rapid suction can be performed directly through the second cavity 72 (compared to the slow suction of exhaust before use); because the connecting channel 40 is smaller than the cross-sectional area of ​​the fluid cavity 202, when the contrast agent or saline solution is sucked from the fluid cavity 202 to the proximal Y-valve 70, the blood has not yet had time to pass through the connecting channel 40 into the balloon cavity 301, and the balloon body 30 is deflated. The limiting portion 33 provided on the inner wall of the balloon body 30 will press against the limiting member 50, prompting the limiting member 50 to block and seal the port 401 in the channel to prevent blood from being sucked into the balloon cavity 301 and the fluid cavity 202, and the greater the pressure difference, the more obvious the blocking and sealing effect.

[0154] The method of using the balloon catheter provided in this embodiment adopts a single suction and exhaust method. There is no need to fill the balloon body 30 or repeatedly fill and suction the balloon body 30 to completely exhaust the air in the balloon cavity 301 and the fluid cavity 202. This is simple and fast, not only ensuring that there is no air residue, but also without deteriorating the performance of the balloon body 30; secondly, in addition to exhausting the air in the balloon cavity 301 and the fluid cavity 202, the air in the connecting channel 40 can also be exhausted, thereby truly achieving "zero air residue" of the air; thirdly, thanks to the fact that the balloon body 30 does not need to be filled during the exhaust process, the balloon catheter provided by the present invention is not only suitable for non-compliant balloons and semi-compliant balloons, but also for compliant balloons; fourthly, the distal end of the balloon catheter is positioned lower than the proximal end and is immersed in a contrast agent or saline solution at the same time. When the balloon cavity and the fluid cavity are filled with a contrast agent or saline solution, the air is visibly exhausted, which is convenient for judgment.

[0155] Although the embodiments of the present invention have been described with reference to the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention. Such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A balloon catheter, characterized in that: include: An outer tube body (10), the inner peripheral wall of which encloses an outer tube cavity; An inner tube body (20) is built into the outer tube cavity; the inner peripheral wall of the inner tube body (20) encloses an inner tube cavity (201); and a fluid cavity (202) is formed between the outer peripheral wall of the inner tube body (20) and the inner peripheral wall of the outer tube body (10); The balloon body (30) comprises a proximal neck (31) and a distal neck (32), wherein the proximal neck (31) is connected to the end of the outer tube body (10), and the distal neck (32) is connected to the distal end of the inner tube body (20); the inner wall of the balloon body (30) and the outer peripheral wall of the inner tube body (20) enclose a balloon cavity (301); a connecting channel (40), one end of which is connected to the inner channel port (401) and the other end of which is connected to the outer channel port (402), wherein the cross-sectional area of ​​the connecting channel (40) is smaller than the cross-sectional area of ​​the fluid cavity (202), wherein the inner channel port (401) is arranged in the balloon cavity (301), and the outer channel port (402) is arranged outside the balloon cavity (301); The limiting member (50) is arranged at the port (401) in the channel; when the pressure outside the balloon cavity (301) is higher than the pressure inside the balloon cavity (301), the limiting member (50) is suitable for unidirectionally opening the port (401) in the channel under the action of the pressure difference, so as to only allow the fluid to flow into the balloon cavity (301) through the connecting channel (40) and not allow the fluid to flow out of the balloon cavity (301) through the connecting channel (40); when the balloon cavity (301) is ) when the pressure inside the balloon cavity (301) is higher than the pressure outside the balloon cavity (301), the limiting member (50) is suitable for sealing the port (401) in the channel under the action of the pressure difference to prevent the fluid from flowing into or out of the balloon cavity (301) through the connecting channel (40); when the balloon body (30) is depressurized and folded to the initial state, the balloon body (30) presses against the limiting member (50) to prevent the fluid from flowing into the balloon cavity (301) through the connecting channel (40).

2. The balloon catheter according to claim 1, characterized in that The limiting member (50) includes a fixing portion (51) and a folding portion (52), wherein the fixing portion (51) is fixedly arranged on the outer peripheral wall of the inner tube body (20) or fixedly arranged on the inner peripheral wall of the balloon body (30), and one side of the folding portion (52) is connected to the fixing portion (51), and the other side is suitable for elastically folding relative to the fixing portion (51) under the action of pressure difference, so as to selectively connect the port (401) in the channel with the balloon cavity (301).

3. The balloon catheter according to claim 1, characterized in that The connecting channel (40) is opened on the inner tube body (20); one end of the connecting channel (40) extends distally to the outside of the inner tube body (20) and forms an outer channel port (402), and the other end extends proximally to the inside of the balloon cavity (301) and forms an inner channel port (401), and the inner channel port (401) is suitable for being connected to the balloon cavity (301).

4. The balloon catheter according to claim 3, characterized in that The channel outer port (402) is opened on the outer peripheral wall of the inner tube body (20); the channel outer port (402) is arranged on the outer peripheral wall of the inner tube body (20) near the distal neck (32); Alternatively, the channel outer port (402) is opened on the distal end surface (21) of the inner tube body (20). The balloon catheter according to claim 1 , wherein: A tube wall body (60) is provided between the outer peripheral wall of the inner tube body (20) and the inner peripheral wall of the balloon body (30), the outer peripheral wall of the tube wall body (60) is fixedly connected to the distal neck (32), and the connecting channel (40) is formed between the tube wall body (60) and the inner tube body (20); one end of the connecting channel (40) extends distally to the outside of the balloon cavity (301) and forms an outer channel port (402), and the other end extends proximally to the inside of the balloon cavity (301) and forms an inner channel port (401), and the inner channel port (401) is suitable for being connected to the balloon cavity (301). The balloon catheter according to claim 1 , wherein: The distal neck portion (32) and the outer tube body (10) are connected to form a first connecting portion (321), and the first connecting portion (321) is provided with the connecting channel (40); one end of the connecting channel (40) extends distally to the outside of the balloon cavity (301) and forms an external channel port (402), and the other end extends proximally to the inside of the balloon cavity (301) and forms an internal channel port (401), and the internal channel port (401) is suitable for being connected to the balloon cavity (301).

7. The balloon catheter according to claim 1, characterized in that The connecting channel (40) is opened on the balloon body (30), one end of the connecting channel (40) extends to the outer peripheral wall of the balloon body (30) and forms an outer channel port (402), and the other end extends to the inner peripheral wall of the balloon body (30) and forms an inner channel port (401), and the inner channel port (401) is suitable for communicating with the balloon cavity (301).

8. The balloon catheter according to claim 3, 5, 6 or 7, characterized in that: The limiting member (50) includes a fixing portion (51) and a folding portion (52), wherein the fixing portion (51) is fixedly arranged on the inner peripheral wall of the balloon body (30), and the folding portion (52) is adapted to selectively fit with the inner peripheral wall of the balloon body (30) under the action of a pressure difference, so as to selectively connect the channel inner port (401) with the balloon cavity (301); Alternatively, the fixing portion (51) is fixedly arranged on the outer peripheral wall of the inner tube body (20), and the folded portion (52) is suitable for selectively fitting with the inner peripheral wall of the balloon body (30) under the action of pressure difference, so as to selectively connect the channel inner port (401) with the balloon cavity (301).

9. The balloon catheter according to claim 1, characterized in that The distal end of the balloon body (30) is folded inward to form a second connecting portion (322); at least a portion of the second connecting portion (322) is suitable for forming the distal neck (32), and the outer peripheral wall of the distal neck (32) is fixedly connected to the distal outer peripheral wall of the inner tube body (20).

10. The balloon catheter according to claim 9, characterized in that The in-channel port (401) is opened on the outer peripheral wall of the inner tube body (20); the distal end of the second connecting portion (322) is suitable for forming the distal neck (32); the proximal end of the second connecting portion (322) is suitable for forming the limiting member (50); and the limiting member (50) is suitable for selectively sealing the in-channel port (401) under the action of a pressure difference. The balloon catheter according to claim 1 , wherein: The channel inner port (401) is provided on the outer peripheral wall of the inner tube body (20); a limiting portion (33) is provided on the inner peripheral wall of the balloon body (30), and the limiting portion (33) is suitable for pressing the limiting member (50) when the balloon body (30) contracts, so that the limiting member (50) blocks the channel inner port (401).

12. The balloon catheter according to claim 11, characterized in that The limiting portion (33) is directly formed by the inner peripheral wall of the balloon body (30) protruding into the balloon cavity (301); Alternatively, the limiting portion (33) is formed by the outer peripheral wall of the balloon body (30) being recessed toward the inner peripheral wall of the balloon body (30), so that the inner peripheral wall of the balloon body (30) protrudes into the balloon cavity (301).

13. The balloon catheter according to claim 1, characterized in that The connecting channel (40) is opened on the inner tube body (20), and the connecting channel (40) is arranged to pass through the inner tube body (20). One end of the connecting channel (40) extends into the inner tube cavity (201) and forms an outer channel port (402), and the other end extends into the balloon cavity (301) and forms an inner channel port (401). The inner channel port (401) is suitable for being connected to the balloon cavity (301).

14. The balloon catheter according to claim 1, characterized in that The channel port (401) is arranged on the outer peripheral wall of the inner tube body (20); the limiting member (50) is beveled on the outer peripheral wall of the inner tube body (20) at the channel port (401) to form a notch (203), and the notch (203) is only connected to the channel port (401) but not to the inner tube cavity (201); the limiting member (50) includes a fixing portion (51) and a folding portion (52), the fixing portion (51) is connected to the outer peripheral wall of the inner tube body (20), and when the folding portion (52) completely covers the channel port (401), the limiting member (50) is completely built into the notch (203).

15. The balloon catheter according to claim 1, characterized in that The limiting member (50) is obliquely cut from the outer peripheral wall of the inner tube body (20) to the inner peripheral wall of the inner tube body (20) to form the connecting channel (40); when the limiting member (50) is completely fitted with the inner tube body (20), the connecting channel (40) is completely closed.

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