Super-selective coaxial microcatheter

Abstract

The utility model relates to the technical field of medical instruments, in particular to a super-selection coaxial microcatheter which comprises a coaxial microcatheter body and a blocking structure, the coaxial microcatheter body comprises a double-cavity catheter, and the double-cavity catheter is provided with an outlet used for injecting medicine into a blood vessel. The blocking structure is arranged at the end, close to the outlet, of the double-cavity catheter and can enter the blood vessel along with the double-cavity catheter, and the blocking structure can expand to block the blood vessel or contract to exit the blood vessel. Medicament is conveyed to a tumor tissue artery through the double-cavity catheter, the blocking structure expands at the end, close to an outlet, of the double-cavity catheter for blocking so as to temporarily block the tumor tissue artery, regurgitation of the medicament is prevented, and normal tissue artery ischemia caused by ectopic embolism formed by reaction of the medicament in the normal tissue artery is avoided. The safety of embolism treatment is improved, meanwhile, rapid injection of the medicament can be achieved, the injection time is shortened, the filling amount of the medicament in the tumor tissue artery is increased, and the treatment effect is enhanced.

Description

Technical Field

[0001] The utility model relates to the technical field of medical devices, in particular to a super-selective coaxial microcatheter. Background Art

[0002] Hydrogel embolization agent is a new type of medical liquid embolization agent. Hydrogel embolization agent is superior to traditional embolization agents in aspects such as drug loading function, operation efficiency, accuracy, response speed, etc., and has broad application prospects in the fields of vascular intervention, tumor treatment, neurointervention, etc. During the process of hydrogel embolization treatment, doctors will use a coaxial microcatheter, that is, a double-lumen catheter is inserted into the femoral artery or other suitable arteries and advanced along the blood vessel to the target position. The double-lumen catheter has two independent channels, which are respectively connected to two syringes, and the syringes are respectively filled with polyethylene glycol precursor and initiator. Then, the doctor presses the two syringes simultaneously and injects them into the double-lumen catheter at the same rate and pressure. Subsequently, the polyethylene glycol precursor and the initiator are injected into the blood vessel through the double-lumen catheter under the action of pressure. The two substances will quickly polymerize into a soft water-based PEG (polyethylene glycol) hydrogel after reaching the blood vessel, and the synthesized water-based PEG hydrogel blocks the blood vessel and causes ischemic necrosis of the tumor tissue.

[0003] See Figure 1 , in the coaxial microcatheter of the current technology, after injecting the polyethylene glycol precursor and the initiator into the tumor tissue artery 02 when the double-lumen catheter 01 is in use, before the formed polymer completely blocks the tumor tissue artery 02, the polyethylene glycol precursor and the initiator will diffuse and be transported to the normal tissue artery 03 under the action of blood flow, thereby forming an ectopic embolism 04 in the normal tissue artery 03 and causing occlusion of the normal tissue artery 03. Summary of the Utility Model

[0004] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the utility model is to provide a super-selective coaxial microcatheter that can temporarily block the tumor tissue artery and prevent drug reflux.

[0005] To solve the above technical problem, the utility model adopts the following technical scheme:

[0006] The utility model provides a super-selective coaxial microcatheter, which includes a coaxial microcatheter body and a blocking structure. The coaxial microcatheter body includes a double-lumen catheter. The double-lumen catheter has an outlet for injecting medicine into the blood vessel. The blocking structure is arranged at one end of the double-lumen catheter close to the outlet and can enter the blood vessel along with the double-lumen catheter. The blocking structure can expand to block the blood vessel or contract to withdraw from the blood vessel.

[0007] Preferably, the blocking structure realizes expansion or contraction through the change of volume.

[0008] Preferably, the occlusion structure includes a balloon sleeved on the double-lumen catheter, and the balloon is inflated or deflated to expand or contract the balloon.

[0009] Preferably, the occlusion structure further includes a trachea and an air pump connected to the trachea. The air pump is connected to the balloon through the trachea to inflate or deflate the balloon.

[0010] Preferably, the double-lumen catheter includes a first catheter and a second catheter. The first catheter and the second catheter are used to deliver different medicaments respectively and both have output ends for outputting medicaments. The output end of the first catheter is sleeved on the output end of the second catheter, and the output ends of the first catheter and the second catheter together form the outlet of the double-lumen catheter.

[0011] Preferably, the coaxial microcatheter body further includes a first syringe and a second syringe. The first catheter and the second catheter both have input ends for receiving medicaments. The input end of the first catheter is connected to the first syringe, and the input end of the second catheter is connected to the second syringe.

[0012] Preferably, the trachea passes through the first catheter. An air hole is formed in the first catheter. The balloon has an inner cavity for storing gas, and the trachea is communicated with the inner cavity of the balloon through the air hole.

[0013] Preferably, the coaxial microcatheter body further includes a conversion component. A conversion cavity is arranged inside the conversion component. The first catheter includes an input catheter and an output catheter respectively communicated with the conversion cavity. One end of the input catheter far from the conversion cavity is used to receive medicaments, and one end of the output catheter far from the conversion cavity is used to output medicaments. The second catheter and the trachea both pass through the conversion component and penetrate into the output catheter through the conversion cavity.

[0014] Compared with the prior art, the present utility model has remarkable progress:

[0015] For the super-selective coaxial microcatheter of the present utility model, medicaments are delivered to the artery of the tumor tissue through the double-lumen catheter, and the occlusion structure is inflated at one end of the double-lumen catheter close to the outlet to block, so as to temporarily block the artery of the tumor tissue, prevent the reflux of medicaments, avoid the formation of ectopic embolism due to the reaction of medicaments in the artery of normal tissues, thus preventing ischemia of the artery of normal tissues, improving the safety of embolization treatment. At the same time, it can realize rapid injection of medicaments, shorten the injection time, increase the filling amount of medicaments in the artery of the tumor tissue, and enhance the treatment effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic diagram of the double-lumen catheter delivering medicaments in a blood vessel in a prior art coaxial microcatheter.

[0017] Figure 2 is a schematic structural diagram of the super-selective coaxial microcatheter according to an embodiment of the present utility model.

[0018] Figure 3 is Figure 2 an enlarged cross-sectional view of part A in

[0019] Figure 4 is Figure 2 an enlarged cross-sectional view of part B in

[0020] Figure 5 a schematic diagram showing a double-lumen catheter delivering a medicament in a blood vessel in a super-selective coaxial microcatheter according to an embodiment of the present invention.

[0021] Among them, the reference numerals are explained as follows:

[0022] 01 Double-lumen catheter

[0023] 02 Tumor tissue artery

[0024] 03 Normal tissue artery

[0025] 04 Ectopic embolization

[0026] 1 Coaxial microcatheter body

[0027] 10 Double-lumen catheter

[0028] 100 Air hole

[0029] 101 First catheter

[0030] 1010 Input catheter

[0031] 1011 Output catheter

[0032] 102 Second catheter

[0033] 11 First syringe

[0034] 12 Second syringe

[0035] 13 Conversion component

[0036] 130 Conversion cavity

[0037] 2 Sealing structure

[0038] 20 Balloon

[0039] 21 Trachea

[0040] 22 Air pump Specific embodiments

[0041] The following further details the specific embodiments of the present invention in conjunction with the accompanying drawings. These embodiments are only used to illustrate the present invention and are not intended to limit the present invention.

[0042] In the description of the present utility model, it should be noted that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to the present utility model. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0043] In the description of the present utility model, it should be noted that unless otherwise clearly specified and defined, the terms "installation", "connection", and "coupling" shall be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0044] In addition, in the description of the present utility model, unless otherwise stated, the meaning of "a plurality of" is two or more.

[0045] As Figures 2 to 5 shown, it is an embodiment of the super-selective coaxial microcatheter of the present utility model.

[0046] See Figure 2 , the super-selective coaxial microcatheter of this embodiment includes a coaxial microcatheter body 1 and a plugging structure 2.

[0047] Among them, the coaxial microcatheter body 1 includes a double-lumen catheter 10. The double-lumen catheter 10 has an outlet for injecting a medicament into a blood vessel. The double-lumen catheter 10 is a flexible hose with a certain length and diameter, and can be slidably inserted into the blood vessel where the medicament needs to be injected, so that the outlet of the double-lumen catheter 10 can move to a designated position in the blood vessel and inject the medicament. The double-lumen catheter 10 has two independent channels. Through the two independent channels, the double-lumen catheter 10 can simultaneously transport two different medicaments, and the channels isolate the medicaments, so that the two different medicaments transported through the double-lumen catheter 10 will not mix with each other inside the double-lumen catheter 10. The positional relationship between the two channels is that one channel is inserted inside the other channel or one channel is adjacent to the other channel. The outlet of the double-lumen catheter 10 is jointly constituted by the output ports where the medicaments flow out from the two channels, and the two medicaments flowing out from the outlet of the double-lumen catheter 10 converge in the blood vessel.

[0048] The occlusion structure 2 is provided at one end of the double-lumen catheter 10 near the outlet and can enter the blood vessel along with the double-lumen catheter 10. The occlusion structure 2 can expand to occlude the blood vessel or contract to withdraw from the blood vessel. The occlusion structure 2 is provided outside the double-lumen catheter 10 and can move synchronously with the double-lumen catheter 10. When the occlusion structure 2 is in the expanded or contracted state, it will not interfere with the outlet of the double-lumen catheter 10 and will not affect the rate of drug delivery through the double-lumen catheter 10. When the occlusion structure 2 expands to fit the inner wall surface of the blood vessel, it will not continue to expand and cause blood vessel dilation. According to the inner diameter of the blood vessel where the drug needs to be injected, the size of the occlusion structure 2 in the final state of occluding the blood vessel can be adjusted adaptively.

[0049] Therefore, when the super-selective coaxial microcatheter of this embodiment is in use, referring to Figure 5 , the outlet end of the double-lumen catheter 10 can be sent into the tumor tissue artery 02. The occlusion structure 2 is in a contracted state and reaches the tumor tissue artery 02 along with the outlet end of the double-lumen catheter 10. Then, the occlusion structure 2 is expanded to the state of occluding the tumor tissue artery 02, temporarily blocking the blood flow and closing the tumor tissue artery 02. Then, the drug is delivered to the tumor tissue artery 02 through the double-lumen catheter 10. Thus, by expanding the occlusion structure 2 at one end of the double-lumen catheter 10 near the outlet to occlude, the tumor tissue artery 02 can be temporarily blocked, preventing drug reflux, avoiding the formation of ectopic embolism 04 due to the reaction of the drug in the normal tissue artery 03, resulting in ischemia of the normal tissue artery 03, improving the safety of embolization treatment. At the same time, rapid injection of the drug can be achieved, shortening the injection time, increasing the filling amount of the drug in the tumor tissue artery 02, and enhancing the treatment effect.

[0050] Preferably, the occlusion structure 2 of this embodiment realizes expansion or contraction through the change in volume. The physical reaction or chemical reaction is combined with the material characteristics of the occlusion structure 2 itself to change its volume to realize expansion or contraction, or an external force is applied to the occlusion structure 2 to change its volume to realize the expansion or contraction of the occlusion structure 2.

[0051] Referring to Figure 2 and Figure 4, Preferably, the occlusion structure 2 of this embodiment includes a balloon 20 sleeved outside the double-lumen catheter 10, and the balloon 20 is inflated or deflated to make the balloon 20 expand or contract. The part where the balloon 20 is connected to the double-lumen catheter 10 is tightly combined with the outer wall surface of the double-lumen catheter 10, so that an inner cavity for storing gas is formed inside the balloon 20. When the balloon 20 is inflated, as more and more gas fills the inner cavity of the balloon 20, the pressure in the cavity gradually increases, and under the action of the internal pressure, the volume of the balloon 20 expands outwards; when the balloon 20 is deflated, the pressure in the cavity gradually decreases, and under the action of the external air pressure of the balloon 20, the volume of the balloon 20 contracts inwards. Further, the inflation speed can be adjusted to control the inflation speed of the balloon 20. Keeping the inflation speed constant, inflating the balloon 20 will cause the balloon 20 to expand evenly, and using the balloon 20 for inflation can make the process of occluding blood vessels more gentle.

[0052] See Figure 2 , Preferably, the occlusion structure 2 of this embodiment further includes a trachea 21 and an air pump 22 connected to the trachea 21. The air pump 22 is connected to the balloon 20 through the trachea 21 and inflates or deflates the balloon 20. The inside of the trachea 21 is hollow and both ends are through. One end of the trachea 21 is connected to the air pump 22, and the other end of the trachea 21 is connected to the inner cavity of the balloon 20. The air pump 22 can be switched to an inflation state or a deflation state according to different needs. When it is necessary to make the balloon 20 expand, the air pump 22 is placed in the inflation state, and the air pump 22 transports the external gas through the trachea 21 to the inner cavity of the balloon 20, and the balloon 20 gradually expands; when it is necessary to make the balloon 20 contract, the air pump 22 is placed in the deflation state, and the air pump 22 generates suction and extracts the gas in the inner cavity of the balloon 20 through the trachea 21, and the balloon 20 gradually contracts.

[0053] See Figure 2 , Preferably, the double-lumen catheter 10 of this embodiment includes a first catheter 101 and a second catheter 102. The first catheter 101 and the second catheter 102 are used to transport different medicaments respectively and both have output ends for outputting medicaments. The output end of the first catheter 101 is sleeved outside the output end of the second catheter 102, and the output ends of the first catheter 101 and the second catheter 102 together form the outlet of the double-lumen catheter 10. After the medicament enters the first catheter 101 / second catheter 102, it is transmitted to the output end of the first catheter 101 / second catheter 102 through the cavity formed inside the first catheter 101 / second catheter 102, and finally enters the blood vessel from the output end of the first catheter 101 / second catheter 102. The two different medicaments transported through the first catheter 101 and the second catheter 102 respectively will not mix with each other during the transmission process, so as to prevent the medicaments from reacting in the double-lumen catheter 10 to form polymers and block the double-lumen catheter 10.

[0054] See Figure 2, preferably, the coaxial microcatheter body 1 of this embodiment further includes a first syringe 11 and a second syringe 12. Both the first catheter 101 and the second catheter 102 have input ends for receiving medicaments. The input end of the first catheter 101 is connected to the first syringe 11, and the input end of the second catheter 102 is connected to the second syringe 12. During use, different medicaments are loaded in the first syringe 11 and the second syringe 12. The first syringe 11 and the second syringe 12 are pressed simultaneously, so that the medicaments in the first syringe 11 and the second syringe 12 are respectively injected into the first catheter 101 and the second catheter 102 from the input ends of the first catheter 101 and the second catheter 102 at the same rate and pressure.

[0055] See Figure 2 and Figure 4 , preferably, the trachea 21 is passed through the first catheter 101. An air hole 100 is formed in the first catheter 101. The balloon 20 has an inner cavity for storing gas. The trachea 21 is communicated with the inner cavity of the balloon 20 through the air hole 100. In this embodiment, the balloon 20 is sleeved on the first catheter 101. There are two joint parts connected to the balloon 20 on the tube wall of the first catheter 101. The air hole 100 is arranged on the tube wall between the two joint parts of the first catheter 101 and penetrates through one side tube wall of the first catheter 101. One end of the trachea 21 away from the air pump 22 has a port for outputting gas. The trachea 21 is passed through the inside of the first catheter 101 and the port of the trachea 21 is connected to the air hole 100. The tube wall of the trachea 21 and the hole wall of the air hole 100 are in sealing fit to prevent the medicament in the first catheter 101 from overflowing from the connection part between the trachea 21 and the air hole 100. During inflation, the air pump 22 conveys gas towards the port direction of the trachea 21 through the trachea 21. The gas is output from the port of the trachea 21 and enters the inner cavity of the balloon 20 through the air hole 100. As the gas in the inner cavity increases, the balloon 20 gradually expands; during deflation, the gas in the balloon 20 enters the trachea 21 through the air hole 100 and the port of the trachea 21 and is conveyed towards the direction of the air pump 22. As the gas in the inner cavity decreases, the balloon 20 gradually contracts.

[0056] See Figure 2 and Figure 3, Preferably, the coaxial microcatheter body 1 of this embodiment further includes a conversion component 13. A conversion cavity 130 is provided inside the conversion component 13. The first catheter 101 includes an input catheter 1010 and an output catheter 1011 that are respectively communicated with the conversion cavity 130. One end of the input catheter 1010 away from the conversion cavity 130 is used to receive the medicament, constituting the input end of the first catheter 101, and is connected to the first syringe 11. One end of the output catheter 1011 away from the conversion cavity 130 is used to output the medicament, constituting the output end of the first catheter 101. The second catheter 102 and the trachea 21 both penetrate through the conversion component 13 and penetrate into the output catheter 1011 through the conversion cavity 130. After the second catheter 102 penetrates into the output catheter 1011, the output end of the second catheter 102 and the end of the output catheter 1011 away from the conversion cavity 130 together constitute the outlet of the double-lumen catheter 10. After the trachea 21 passes through the conversion cavity 130 and penetrates into the output catheter 1011, it is communicated with the inner cavity of the balloon 20 through the air hole 100. During use, the medicament received by the input catheter 1010 is transmitted to the conversion cavity 130. The input catheter 1010 continuously conveys the medicament. The medicament enters the output catheter 1011 through the conversion cavity 130. After the conversion cavity 130 is filled with the medicament, the medicament entering the output catheter 1011 is output from the end of the output catheter 1011 away from the conversion cavity 130 into the blood vessel under the action of pressure. At the same time, the medicament conveyed by the second catheter 102 is output from the output end of the second catheter 102 into the blood vessel. The medicament conveyed by the second catheter 102 and the medicament conveyed by the output catheter 1011 enter the blood vessel through the outlet of the double-lumen catheter 10 and are mixed and reacted with each other to form a polymer.

[0057] The working process of the super-selective coaxial microcatheter of this embodiment is as follows:

[0058] First, through the ultrasonic guidance technique, the outlet of the double-lumen catheter 10 for injecting the medicament into the blood vessel is pulled to a position suitable for injecting the medicament in the tumor tissue artery 02, and the position of the outlet of the double-lumen catheter 10 is kept fixed. The balloon 20 is in a contracted state and reaches the tumor tissue artery 02 synchronously with the outlet end of the double-lumen catheter 10.

[0059] Then, start the air pump 22. The air pump 22 continuously inputs gas into the inner cavity of the balloon 20 through the trachea 21, and the balloon 20 gradually expands. During the expansion process of the balloon 20, observe the state of the balloon 20 through the B-ultrasound machine. When the balloon 20 expands to fit the inner wall surface of the blood vessel, stop inflating the balloon 20 and keep the state of the balloon 20 when the inflation is completed. At this time, the balloon 20 is anchored in the tumor tissue artery 02, temporarily blocking the blood flow and sealing the blood vessel.

[0060] Subsequently, the first syringe 11 and the second syringe 12 are simultaneously pressed. Different medicaments are contained in the first syringe 11 and the second syringe 12, and the two medicaments can react with each other to form a polymer. The medicaments in the first syringe 11 and the second syringe 12 are respectively injected into the first conduit 101 and the second conduit 102 from the input ends of the first conduit 101 and the second conduit 102 at the same rate and pressure. The medicament in the first syringe 11 is transmitted through the first conduit 101, and the medicament in the second syringe 12 is transmitted through the second conduit 102. The two medicaments are mixed and react to form a polymer after entering the tumor tissue artery 02 through the outlet of the double-lumen conduit 10. Refer to Figure 5 , since the tumor tissue artery 02 is blocked by the balloon 20, the medicaments entering the tumor tissue artery 02 can only fill the tumor tissue artery 02 and cannot move to other blood vessels. The medicaments are continuously injected into the tumor tissue artery 02 until the polymer formed after the medicaments reach a certain filling amount can block the blood flow in the tumor tissue artery 02.

[0061] Finally, the air pump 22 is switched to the air extraction state, and the gas in the balloon 20 is extracted through the trachea 21. After the balloon 20 shrinks to the state before inflation, the double-lumen conduit 10 carrying the balloon 20 is withdrawn from the patient's body, and at this time, the operation of blocking the tumor tissue artery 02 is completed.

[0062] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and replacements can be made, and these improvements and replacements should also be regarded as the protection scope of the present invention.

Claims

1. A super-selective coaxial microcatheter, characterized in that, It includes a coaxial microcatheter body (1) and a plugging structure (2). The coaxial microcatheter body (1) includes a double-lumen catheter (10). The double-lumen catheter (10) has an outlet for injecting a medicament into a blood vessel. The plugging structure (2) is provided at one end of the double-lumen catheter (10) near the outlet and can enter the blood vessel along with the double-lumen catheter (10). The plugging structure (2) can expand to plug the blood vessel or contract to withdraw from the blood vessel.

2. The super-selective coaxial microcatheter according to claim 1, wherein The plugging structure (2) realizes expansion or contraction through the change in its volume.

3. The super-selective coaxial microcatheter according to claim 2, characterized in that, The plugging structure (2) includes a balloon (20) sleeved outside the double-lumen catheter (10). The balloon (20) is inflated or deflated to expand or contract the balloon (20).

4. The super-selective coaxial microcatheter according to claim 3, wherein The plugging structure (2) further includes an air tube (21) and an air pump (22) connected to the air tube (21). The air pump (22) is connected to the balloon (20) through the air tube (21) to inflate or deflate the balloon (20).

5. The super-selective coaxial microcatheter according to claim 4, characterized in that, The double-lumen catheter (10) includes a first catheter (101) and a second catheter (102). The first catheter (101) and the second catheter (102) are used to respectively transport different medicaments and both have output ends for outputting the medicaments. The output end of the first catheter (101) is sleeved outside the output end of the second catheter (102). The outlet of the double-lumen catheter (10) is jointly constituted by the output end of the first catheter (101) and the output end of the second catheter (102).

6. The super-selective coaxial microcatheter according to claim 5, characterized in that, The coaxial microcatheter body (1) further includes a first syringe (11) and a second syringe (12). The first catheter (101) and the second catheter (102) both have input ends for receiving medicaments. The input end of the first catheter (101) is connected to the first syringe (11), and the input end of the second catheter (102) is connected to the second syringe (12).

7. The super-selective coaxial microcatheter according to claim 5, characterized in that, The air tube (21) passes through the first catheter (101). An air hole (100) is provided on the first catheter (101). The balloon (20) has an inner cavity for storing gas. The air tube (21) is communicated with the inner cavity of the balloon (20) through the air hole (100).

8. The super-selective coaxial microcatheter according to claim 7, characterized in that The coaxial microcatheter body (1) further includes a conversion component (13). A conversion cavity (130) is provided inside the conversion component (13). The first catheter (101) includes an input catheter (1010) and an output catheter (1011) respectively communicated with the conversion cavity (130). The end of the input catheter (1010) far from the conversion cavity (130) is used to receive a medicament, and the end of the output catheter (1011) far from the conversion cavity (130) is used to output the medicament. The second catheter (102) and the air tube (21) both pass through the conversion component (13) and penetrate into the output catheter (1011) through the conversion cavity (130).

Images