Double-disengagement-point electrolysis disengagement micro-catheter

Abstract

The invention provides a double-release-point electrolysis release micro-catheter, which relates to the field of medical instruments and comprises a far-section catheter, a middle-section catheter and a near-section catheter, the far-section catheter is connected with the middle-section catheter and is provided with a far-end disengagement point; the middle-section catheter is connected with the near-section catheter and is provided with a near-end disengagement point; the device further comprises a first anode conductor, a second anode conductor, a cathode conductor and a power supply. The first anode conductor is respectively connected with the far-end release and the positive pole of the power supply; the second anode conductor is respectively connected with the near-end release point and the positive pole of the power supply; one end of the cathode conductor is fixed on the outer side of the near-section catheter, and the other end is connected with the cathode of the power supply. The problems that in the prior art, due to the fact that glue injected into a blood vessel gradually coagulates to form blockage and forms a gap with a catheter, if glue is injected continuously, the glue is subjected to pressure formed by blockage, easily flows back along the outer wall of the catheter from the gap and covers a metal release point, a current loop cannot be formed, and the service life of the catheter is affected can be solved. The far section and the near section of the catheter cannot be separated.

Description

Technical Field

[0001] The present invention relates to the field of medical devices, in particular to a double-release-point electro-release microcatheter. Background Art

[0002] A microcatheter is a percutaneous medical device that can deliver diagnostic or therapeutic materials to specific locations through blood vessels or other cavities in the human body. In the treatment of cerebral arteriovenous malformations, microcatheters are mainly used clinically to deliver liquid embolic glue for embolization therapy. However, the distal end of the microcatheter often adheres to the embolic glue during the delivery process, making it difficult to remove the catheter.

[0003] For example, Chinese patent application number 202410423991.8 discloses an electrolytically detachable catheter device, comprising a developing marker, a detachable distal catheter section, a proximal catheter section, a support tube, a tube seat, an electrode rod, an anode conductive wire, and a cathode conductive wire. The catheter device provided by this patent utilizes the principle of electrolytic reaction to allow the predetermined metal release point of the catheter to undergo controllable oxidative decomposition and complete separation in a short period of time, thereby achieving the release of the detachable distal catheter section and the proximal catheter section, thereby solving the problem of being unable to remove the catheter due to adhesion of the liquid embolic glue to the catheter.

[0004] However, when using the catheter device provided by the above patent to inject glue, the glue injected into the blood vessel will gradually coagulate and form a blockage, forming a gap between the glue and the catheter. If the glue injection is still continued at this time, the glue will be subjected to the pressure formed by the blockage. The glue subsequently flowing out of the catheter will be forced to flow back from the gap along the outer wall of the catheter under pressure and cover the metal release point, thereby preventing the metal release point from contacting the blood to form an electric current loop. The distal section of the detachable catheter and the proximal section of the catheter cannot be separated, thereby causing a catheter retention accident and increasing the risk of surgery. Summary of the Invention

[0005] In response to the above-mentioned problems, the present invention provides a double-release-point electrolytically detachable microcatheter, which can solve the problem in the prior art that when injecting glue, the glue injected into the blood vessel will gradually coagulate and form a blockage, forming a gap between the glue and the catheter. At this time, if the glue injection continues, the glue will be subjected to the pressure formed by the blockage, and the glue subsequently flowing out of the catheter will be forced to flow back from the gap along the outer wall of the catheter under pressure, and cover the metal release point, so that the metal release point cannot contact the blood to form an electric current loop, and the detachable distal section and proximal section of the catheter cannot be separated, thereby causing catheter retention accidents and increasing surgical risks. The invention avoids accidents of catheter retention due to glue backflow and reduces surgical risks.

[0006] To achieve the above object, the technical solution adopted by the present invention is:

[0007] The present invention provides a double-release-point electrolytically detachable microcatheter, comprising a distal catheter, a middle catheter, and a proximal catheter; the proximal end of the distal catheter is connected to the distal end of the middle catheter, and a distal release point is provided at the connection; the proximal end of the middle catheter is connected to the distal end of the proximal catheter, and a proximal release point is provided at the connection;

[0008] It also includes a first anode conductor, a second anode conductor, a cathode conductor and a power supply; the first anode conductor and the second anode conductor are both located in the side wall of the double-release-point electrolytic release microcatheter; one end of the first anode conductor is connected to the distal release point, and the other end is connected to the positive pole of the power supply; the second anode conductor is connected to the proximal release point, and the other end is connected to the positive pole of the power supply; one end of the cathode conductor is fixed to the outside of the proximal catheter, and the other end is connected to the negative pole of the power supply.

[0009] The double-release-point electrolytically detachable microcatheter provided by the present invention preferably comprises the distal catheter, the middle catheter and the proximal catheter each comprising an outer layer, an intermediate layer and an inner layer; the outer layer is a biocompatible polymer layer; the intermediate layer is a metal reinforcement layer; and the inner layer is a PTFE lubricating layer.

[0010] The double-release-point electrolytic release microcatheter provided by the present invention preferably has an outer layer made of polyurethane, Pebax or Nylon; and a middle layer made of 304 stainless steel, 316L stainless steel or NiTi.

[0011] The dual-release-point electrolytically detachable microcatheter provided by the present invention preferably further comprises two development markers; the two development markers are respectively located on the distal catheter and the middle catheter.

[0012] The dual-release-point electrolytic release microcatheter provided by the present invention preferably further comprises two NTC thermistors; the two NTC thermistors are respectively arranged at the distal release point and the proximal release point; and the NTC thermistors are electrically connected to the power supply.

[0013] The double-release-point electrolytic release microcatheter provided by the present invention preferably comprises a distal release point comprising a first release wire and a PLGA layer; the first release wire is spiral-shaped; the PLGA layer covers the outside of the first release wire;

[0014] The proximal release point includes a second release thread and a TPU layer; the second release thread is cross-woven; and the TPU layer covers the outside of the second release thread.

[0015] In the dual-release-point electrolytic release microcatheter provided by the present invention, preferably, a plurality of grooves are provided on the PLGA layer and the TPU layer; the grooves are circumferentially arranged with the axis of the dual-release-point electrolytic release microcatheter as the center;

[0016] A plurality of through holes are formed on the PLGA layer and the TPU layer.

[0017] The double-release-point electrolytic release microcatheter provided by the present invention is preferably such that the cathode conductor is a diffusion stress tube; the diffusion stress tube is sleeved on the outside of the proximal section catheter; an insulating layer is provided between the diffusion stress tube and the proximal section catheter; and the diffusion stress tube is connected to the negative pole of the power supply.

[0018] The dual-release-point electrolytic release microcatheter provided by the present invention preferably further comprises a third anode conductor;

[0019] The first anode conductor is arranged in the side wall of the middle section of the catheter; the second anode conductor is arranged in the side wall of the proximal section of the catheter; the third anode conductor is arranged in the side wall of the distal section of the catheter; the first anode conductor and the second anode conductor are respectively connected to the two ends of the proximal release point; the second anode conductor and the third anode conductor are respectively connected to the two ends of the distal release point.

[0020] The double-release-point electrolytic release microcatheter provided by the present invention is preferably such that the first anode conductor passes through the middle section catheter, the proximal release point and the proximal section catheter; the first anode conductor is arranged in the side walls of the middle section catheter, the proximal release point and the proximal section catheter; and the second anode conductor is arranged in the side wall of the proximal section catheter.

[0021] The above technical solution has the following advantages or beneficial effects:

[0022] The double-release-point electrolytically detachable microcatheter provided by the present invention comprises a distal catheter, a middle catheter and a proximal catheter; the proximal end of the distal catheter is connected to the distal end of the middle catheter, and a distal release point is provided at the connection; the proximal end of the middle catheter is connected to the distal end of the proximal catheter, and a proximal release point is provided at the connection; by selecting either the distal release point or the proximal release point, electrifying it and breaking it, the front section and the rear section of the release point can be separated, thereby avoiding the situation where glue adheres to the microcatheter outlet, so that the microcatheter can be withdrawn in time; further, by setting two release points at different positions on the microcatheter, different positions of the microcatheter can be selectively electrolytically separated to adapt to different application environments. In particular, when using the microcatheter to inject glue, the glue injected into the blood vessel will gradually coagulate to form a blockage, forming a gap with the microcatheter. At this time, if it is still maintained When glue is continuously injected, the glue is subjected to the pressure formed by the blockage. The glue subsequently flowing out of the microcatheter outlet, that is, the distal catheter, is forced to flow back from the gap along the outer wall of the distal catheter under pressure and cover the distal release point, so that the distal release point cannot contact the blood to form a current loop. The distal catheter and the middle catheter cannot be electrolytically separated, and a microcatheter retention accident occurs. For this reason, a proximal release point is set at the proximal position of the distal release point. Since the glue coagulates at the microcatheter outlet and the coagulated glue is sticky, the speed of the glue backflow on the outer wall of the microcatheter is slow, and the blood flow outside the microcatheter flows forward, which is opposite to the direction of the glue backflow, which can slow down the speed of the glue backflow outside the microcatheter, thereby preventing the glue from flowing back to the proximal release point. In this case, the operator can break and separate the microcatheter through the proximal release point, thereby successfully removing the tube;

[0023] In order to achieve electrolysis of the distal release point and the proximal release point by energizing, the device further includes a first anode conductor, a second anode conductor, a cathode conductor and a power supply; one end of the first anode conductor is connected to the distal release point, and the other end is connected to the positive pole of the power supply; the second anode conductor is connected to the proximal release point, and the other end is connected to the positive pole of the power supply, so that the current output by the power supply can pass through the distal release point and the proximal release point, thereby achieving electrolytic splitting of the distal release point and the proximal release point; in order to prevent the current released from the power supply from directly contacting the blood when passing through the first anode conductor or the second anode conductor, the first anode conductor and the second anode conductor are both located in the side wall of the dual-release-point electrolysis release microcatheter, thereby ensuring that the first anode conductor and the second anode conductor can respectively allow the current released from the power supply to accurately pass through the distal release point and the proximal release point; one end of the cathode conductor is fixed to the outside of the proximal catheter, the distal release point or the proximal release point is connected to the cathode conductor through blood, and the other end of the cathode conductor is connected to the negative pole of the power supply to achieve a circuit loop;

[0024] The existing technology uses a single release point. When injecting glue, the glue injected into the blood vessel will gradually coagulate and form a blockage, forming a gap between the catheter and the glue. At this time, if the glue injection is still continued, the glue will be subjected to the pressure formed by the blockage. The glue that subsequently flows out of the catheter is forced to easily flow back from the gap along the outer wall of the catheter under pressure and cover the metal release point, so that the metal release point cannot contact the blood to form a current loop, and the detachable distal section and proximal section of the catheter cannot be separated, thereby causing a catheter retention accident, increasing the surgical risk; the dual-release-point electro-detachable microcatheter provided by the present invention can effectively avoid the problem of microcatheter retention caused by the distal release point being unable to form a circuit loop with the cathode conductor when glue flows back, by setting the distal release point and the proximal release point at the same time. The circuit loop is formed with the cathode conductor through the proximal release point, thereby breaking and separating the microcatheter at the proximal release point, thereby avoiding catheter retention accidents and reducing surgical risks. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention and its features, configurations, and advantages will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings. Like reference numerals indicate like parts throughout the drawings. The drawings are not drawn to scale, emphasis instead being placed on illustrating the subject matter of the present invention.

[0026] Figure 1 It is a schematic cross-sectional structural diagram of the double-release-point electrolytic release microcatheter provided in Example 1 of the present invention.

[0027] Figure 2 It is a schematic diagram of the cross-sectional structure of the distal release point in the double-release-point electrolytic release microcatheter provided in Example 1 of the present invention.

[0028] Figure 3 yes Figure 2 A partial enlarged schematic diagram.

[0029] Figure 4 It is a schematic diagram of the cross-sectional structure of the proximal release point in the double-release-point electrolytic release microcatheter provided in Example 1 of the present invention.

[0030] Figure 5 yes Figure 4 A partial enlarged schematic diagram.

[0031] Figure 6 It is a schematic cross-sectional structure diagram of the grooves and through holes in the double-release-point electrolytic release microcatheter provided in Example 1 of the present invention.

[0032] Figure 7 It is a schematic cross-sectional structural diagram of a diffusion stress tube sheathed outside the proximal catheter in a double-release-point electrolytic release microcatheter provided in Example 1 of the present invention. DETAILED DESCRIPTION

[0033] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0034] Example 1:

[0035] like Figures 1 and 2 and Figure 3 As shown, a double-release-point electrolytically detachable microcatheter provided in Example 1 of the present invention includes a distal catheter 1, a middle catheter 2, and a proximal catheter 3; the proximal end of the distal catheter 1 is connected to the distal end of the middle catheter 2, and a distal release point 4 is provided at the connection; the proximal end of the middle catheter 2 is connected to the distal end of the proximal catheter 3, and a proximal release point 5 is provided at the connection;

[0036] It also includes a first anode conductor, a second anode conductor, a cathode conductor and a power supply; the first anode conductor and the second anode conductor are both located in the side wall of the double-release-point electrolytic release microcatheter; one end of the first anode conductor is connected to the distal release point, and the other end is connected to the positive pole of the power supply; the second anode conductor is connected to the proximal release point, and the other end is connected to the positive pole of the power supply; one end of the cathode conductor is fixed to the outside of the proximal catheter, and the other end is connected to the negative pole of the power supply.

[0037] When using the double-release-point electrolytically detachable microcatheter provided in Example 1 of the present invention, the double-release-point electrolytically detachable microcatheter is assembled on the tube seat so that the proximal catheter 3 is fixed to the tube seat; the double-release-point electrolytically detachable microcatheter is extended into the blood vessel so that the tube mouth of the distal catheter 1 is at the gel position required by the blood vessel, glue is injected into the microcatheter, and the glue is transported to the distal catheter 1 for release; after the glue is released, the positive electrode of the power supply releases current to the first anode conductor, and the current is directed to the distal release point 4. The distal release point 4 and the cathode conductor are connected through the blood, and the current is discharged by The cathode conductor returns to the negative pole of the power supply. At this time, under the continuous action of the current, the distal release point 4 undergoes an electrolytic reaction and breaks, separating the distal catheter 1 and the middle catheter 2; if the distal release point 4 cannot break, the current is released to the second anode conductor through the positive pole of the power supply, and the current is directed to the proximal release point 5. The proximal release point 5 and the cathode conductor are connected through the blood, and the current returns to the negative pole of the power supply from the cathode conductor. At this time, under the continuous action of the current, the proximal release point 5 undergoes an electrolytic reaction and breaks, separating the middle catheter 2 and the proximal catheter 3.

[0038] The double-release-point electrolytically detachable microcatheter provided in Example 1 of the present invention comprises a distal catheter 1, a middle catheter 2 and a proximal catheter 3; the proximal end of the distal catheter 1 is connected to the distal end of the middle catheter 2, and a distal release point 4 is provided at the connection; the proximal end of the middle catheter 2 is connected to the distal end of the proximal catheter 3, and a proximal release point 5 is provided at the connection; by selecting either the distal release point 4 or the proximal release point 5, electrifying and breaking it, the front and rear sections of the release point can be separated, thereby avoiding the situation where glue adheres to the microcatheter outlet, so that the microcatheter can be withdrawn in time; further, by setting two release points at different positions on the microcatheter, different positions of the microcatheter can be selectively electrolytically separated to adapt to different application environments. In particular, when using the microcatheter to inject glue, the glue injected into the blood vessel will gradually coagulate to form a blockage, forming a gap with the microcatheter. At this time, if Glue injection is still continued, and the glue is subjected to the pressure formed by the blockage. The glue subsequently flowing out of the microcatheter outlet, that is, the distal catheter 1, is forced to flow back from the gap along the outer wall of the distal catheter 1 under pressure, and covers the distal release point 4, so that the distal release point 4 cannot contact the blood to form a current loop, and the distal catheter 1 and the middle catheter 2 cannot be electrolytically separated, thereby causing a microcatheter retention accident. For this reason, a proximal release point 5 is set at the proximal position of the distal release point 4. Since the glue coagulates at the microcatheter outlet and the coagulated glue is sticky, the speed of the glue backflow on the outer wall of the microcatheter is slow, and the blood flow outside the microcatheter flows forward, which is opposite to the direction of the glue backflow, which can slow down the speed of the glue backflow outside the microcatheter, thereby preventing the glue from flowing back to the proximal release point 5, so that the operator can break and separate the microcatheter through the proximal release point 5 in this case, thereby successfully withdrawing the tube;

[0039] In order to realize the electrolysis of the distal release point 4 and the proximal release point 5 by energizing, the device further includes a first anode conductor, a second anode conductor, a cathode conductor and a power supply; one end of the first anode conductor is connected to the distal release point 4, and the other end is connected to the positive pole of the power supply; the second anode conductor is connected to the proximal release point 5, and the other end is connected to the positive pole of the power supply, so that the current output by the power supply can pass through the distal release point 4 and the proximal release point 5, thereby realizing the electrolytic splitting of the distal release point 4 and the proximal release point 5; in order to avoid the current released from the power supply passing through The first anode conductor or the second anode conductor is in direct contact with the blood. The first anode conductor and the second anode conductor are both located within the side wall of the dual-release-point electrolytic release microcatheter, thereby ensuring that the first anode conductor and the second anode conductor can respectively allow the current released from the power source to accurately pass through the distal release point 4 and the proximal release point 5; one end of the cathode conductor is fixed to the outside of the proximal catheter, the distal release point 4 or the proximal release point 5 is connected to the cathode conductor through the blood, and the other end of the cathode conductor is connected to the negative pole of the power source to achieve a circuit loop;

[0040] The existing technology uses a single release point. When injecting glue, the glue injected into the blood vessel will gradually coagulate and form a blockage, forming a gap between the catheter and the glue. If the glue injection is still continued at this time, the glue will be subjected to the pressure formed by the blockage. The glue that subsequently flows out of the catheter is forced to flow back from the gap along the outer wall of the catheter under pressure and cover the metal release point, so that the metal release point cannot contact the blood to form a current loop, and the detachable distal section and proximal section of the catheter cannot be separated, thereby causing a catheter retention accident, increasing the surgical risk; the dual-release-point electro-detachable microcatheter provided in Example 1 of the present invention, by simultaneously setting a distal release point 4 and a proximal release point 5, can effectively avoid the problem that the distal release point 4 cannot form a circuit loop with the cathode conductor when the glue flows back, causing the microcatheter to be retained, and realizes the formation of a circuit loop with the cathode conductor through the proximal release point 5, thereby breaking and separating the microcatheter at the proximal release point 5, thereby avoiding the accident of catheter retention and reducing the surgical risk.

[0041] like Figure 1 As shown, the double-release-point electrolytically detachable microcatheter provided in Example 1 of the present invention preferably comprises the distal catheter 1, the middle catheter 2 and the proximal catheter 3 each including an outer layer 01, an intermediate layer 02 and an inner layer 03. The outer layer 01 is a biocompatible polymer layer for compatibility with blood, the intermediate layer 02 is a metal reinforcement layer for supporting the shape of the microcatheter, and the inner layer 03 is a PTFE lubricating layer for preventing glue from adhering to the microcatheter.

[0042] The double-release-point electrolytically detachable microcatheter provided in Example 1 of the present invention preferably has an outer layer 01 made of a biocompatible polymer layer made of materials such as polyurethane, Pebax or Nylon, so that the outer layer 01 has good biocompatibility; the middle layer 02 can be made of a metal reinforcement layer made of materials such as 304 stainless steel, 316L stainless steel or NiTi, so that the middle layer 02 has a good supporting effect.

[0043] like Figure 1 As shown, the double-release-point electrolytically detachable microcatheter provided in Example 1 of the present invention preferably also includes two developing marks 6, which are respectively located on the distal catheter 1 and the middle catheter 2, and are used to identify the positions of the distal catheter 1 and the middle catheter 2 in the blood vessel, so as to accurately locate the position of glue discharge and determine whether the distal catheter 1 and the middle catheter 2 are broken and separated.

[0044] The dual-release-point electrolytic release microcatheter provided in Example 1 of the present invention preferably also includes two NTC thermistors. Since electrolysis is used to break the distal release point 4 or the proximal release point 5, heat will be generated. If the heat is high, it may damage the blood vessels. Therefore, it is necessary to monitor the heat generated by electrolysis. Specifically, the two NTC thermistors are respectively set at the distal release point 4 and the proximal release point 5, and the NTC thermistors are electrically connected to the power supply. When the temperature generated by electrolysis is higher than 60°C, the power supply is controlled to be cut off.

[0045] like Figures 2 to 5 As shown, the double-release-point electrolytic release microcatheter provided in Example 1 of the present invention preferably has the distal release point 4 and the proximal release point 5 both in a tubular shape in order to ensure that the outer surface and the inner cavity of the microcatheter are consistent;

[0046] Furthermore, to ensure that the microcatheter can adapt to the extension direction of the blood vessel after being inserted into the blood vessel, the distal release point 4 located deeper in the blood vessel is more flexible than the proximal release point 5. Since the curvature of the microcatheter needs to be adjusted at the distal release point 4 to adapt to the extension direction of the blood vessel, the distal release point 4 includes a first release thread 41 and a PLGA layer 42. The first release thread 41 is spirally shaped, giving the distal release point 4 good flexibility. The PLGA layer 42 is covered on the outside of the first release thread 41, making the first release thread 41 more compatible with blood.

[0047] In order to ensure that the microcatheter can be withdrawn after it breaks at the distal release point 4, the proximal release point 5 is more resilient than the distal release point 4; since the proximal release point 5 needs to withstand the stress generated by the pulling of the microcatheter, the proximal release point 5 includes a second release wire 51 and a TPU layer 52, so that the second release wire 51 is cross-woven, so that the proximal release point 5 has good resilient, and the TPU layer 52 is covered on the outside of the second release wire 51, so that the second release wire 51 has better compatibility with blood.

[0048] like Figure 6 As shown, the dual-release-point electrolytically detachable microcatheter provided in Example 1 of the present invention preferably has a plurality of grooves 4501 formed on the PLGA layer 42 and the TPU layer 52 to prevent the distal release point 4 and the proximal release point 5 from being unable to smoothly contact blood and breaking after being coated with the PLGA layer 42 and the TPU layer 52. The grooves 4501 are circumferentially arranged with the axis of the dual-release-point electrolytically detachable microcatheter as the center. By providing the grooves 4501 or pre-treating the distal release point 4 and the proximal release point 5 with cracks, the PLGA layer 42 and the TPU layer 52 can be more easily detached during electrolytic detachment, so that the distal release point 4 and the proximal release point 5 break faster, thereby improving the efficiency of tube removal.

[0049] A number of through holes 4502 are provided on the PLGA layer 42 and the TPU layer 52. The through holes 4502 connect the outer side and the inner side of the PLGA layer 42, exposing the first release thread 41 to the outside, making it easy for the first release thread 41 to come into contact with blood; similarly, the through holes 4502 connect the outer side and the inner side of the TPU layer 52, exposing the second release thread 51 to the outside, making it easy for the second release thread 51 to come into contact with blood.

[0050] like Figure 7 As shown, in the double-release-point electrolytically release microcatheter provided in Example 1 of the present invention, preferably, the cathode conductor is a diffusion stress tube 7, which is connected to the tube seat. The diffusion stress tube 7 is sleeved on the outside of the proximal catheter 3, and an insulating layer 8 is provided between the diffusion stress tube 7 and the proximal catheter 3. The diffusion stress tube 7 is connected to the negative pole of the power supply. When the diffusion stress tube 7 and the proximal catheter 3 enter the blood vessel together, the diffusion stress tube 7 can contact the blood to form a circuit loop; further, the use of the diffusion stress tube 7 sleeved on the outside of the proximal catheter 3 can avoid the conductive wire from breaking when it is extended into the blood vessel, thereby improving the risk resistance of the microcatheter.

[0051] The double-release-point electrolytic release microcatheter provided in Example 1 of the present invention preferably further comprises a third anode conductor;

[0052] The first anode conductor is arranged in the side wall of the middle section catheter 2, the second anode conductor is arranged in the side wall of the proximal section catheter 3, and the third anode conductor is arranged in the side wall of the distal section catheter 1, so that the first anode conductor and the second anode conductor are respectively connected to the two ends of the proximal release point 5, and the second anode conductor and the third anode conductor are respectively connected to the two ends of the distal release point 4, so that the first anode conductor, the second anode conductor and the third anode conductor are connected in series, and the distal release point 4 and the proximal release point 5 are electrolyzed simultaneously by a power supply; in order to realize the process of releasing the distal release point 4 first and then releasing the proximal release point 5, a first electrolytic wire with a spiral structure that is easier to electrolyze is used at the distal release point 4, and a second electrolytic wire with a braided structure that is more difficult to electrolyze is used at the proximal release point 5. The implementation method of first small current and then large current is adopted, and a small current is used to electrolyze the distal release point 4. If the distal release point 4 is covered with glue, a large current is used to electrolyze the proximal release point 5.

[0053] In the dual-release-point electrolytically detachable microcatheter provided in Example 1 of the present invention, preferably, the middle layer 02 can adopt one of a braided structure, a coil structure, or a hypotube structure, or a combination of multiple structures, such as a braided structure on the outer side and a coil structure on the inner side. By adopting the above structures, the microcatheter can have better pushability, flexibility, tracking, kink resistance, and support, thereby ensuring safe and effective surgery.

[0054] When the intermediate layer 02 is made of a braided structure, several, for example, eight, of the first anode conductor, the second anode conductor, and the third anode conductor can be selected from a plurality of braided wires and used as conductive wires.

[0055] Example 2:

[0056] like Figures 1 and 2 and Figure 3 As shown, a dual-release-point electrolytically detachable microcatheter provided in Example 2 of the present invention includes a distal catheter 1, a middle catheter 2, and a proximal catheter 3; the proximal end of the distal catheter 1 is connected to the distal end of the middle catheter 2, and a distal release point 4 is provided at the connection; the proximal end of the middle catheter 2 is connected to the distal end of the proximal catheter 3, and a proximal release point 5 is provided at the connection;

[0057] It also includes a first anode conductor, a second anode conductor, a cathode conductor and a power supply; the first anode conductor and the second anode conductor are both located in the side wall of the double-release-point electrolytic release microcatheter; one end of the first anode conductor is connected to the distal release point, and the other end is connected to the positive pole of the power supply; the second anode conductor is connected to the proximal release point, and the other end is connected to the positive pole of the power supply; one end of the cathode conductor is fixed to the outside of the proximal catheter, and the other end is connected to the negative pole of the power supply.

[0058] When using the double-release-point electrolytically detachable microcatheter provided in Example 2 of the present invention, the double-release-point electrolytically detachable microcatheter is assembled on the tube seat so that the proximal catheter 3 is fixed to the tube seat; the double-release-point electrolytically detachable microcatheter is extended into the blood vessel so that the tube mouth of the distal catheter 1 is at the gel position required by the blood vessel, glue is injected into the microcatheter, and the glue is transported to the distal catheter 1 for release; after the glue is released, the positive electrode of the power supply releases current to the first anode conductor, and the current is directed to the distal release point 4. The distal release point 4 and the cathode conductor are connected through the blood, and the current is discharged by The cathode conductor returns to the negative pole of the power supply. At this time, under the continuous action of the current, the distal release point 4 undergoes an electrolytic reaction and breaks, separating the distal catheter 1 and the middle catheter 2; if the distal release point 4 cannot break, the current is released to the second anode conductor through the positive pole of the power supply, and the current is directed to the proximal release point 5. The proximal release point 5 and the cathode conductor are connected through the blood, and the current returns to the negative pole of the power supply from the cathode conductor. At this time, under the continuous action of the current, the proximal release point 5 undergoes an electrolytic reaction and breaks, separating the middle catheter 2 and the proximal catheter 3.

[0059] The double-release-point electrolytically detachable microcatheter provided in Example 2 of the present invention comprises a distal catheter 1, a middle catheter 2 and a proximal catheter 3; the proximal end of the distal catheter 1 is connected to the distal end of the middle catheter 2, and a distal release point 4 is provided at the connection; the proximal end of the middle catheter 2 is connected to the distal end of the proximal catheter 3, and a proximal release point 5 is provided at the connection; by selecting either the distal release point 4 or the proximal release point 5, electrifying and breaking it, the front and rear sections of the release point can be separated, thereby avoiding the situation where glue adheres to the microcatheter outlet, so that the microcatheter can be withdrawn in time; further, by setting two release points at different positions on the microcatheter, different positions of the microcatheter can be selectively electrolytically separated to adapt to different application environments. In particular, when using the microcatheter to inject glue, the glue injected into the blood vessel will gradually coagulate to form a blockage, forming a gap with the microcatheter. At this time, if Glue injection is still continued, and the glue is subjected to the pressure formed by the blockage. The glue subsequently flowing out of the microcatheter outlet, that is, the distal catheter 1, is forced to flow back from the gap along the outer wall of the distal catheter 1 under pressure, and covers the distal release point 4, so that the distal release point 4 cannot contact the blood to form a current loop, and the distal catheter 1 and the middle catheter 2 cannot be electrolytically separated, thereby causing a microcatheter retention accident. For this reason, a proximal release point 5 is set at the proximal position of the distal release point 4. Since the glue coagulates at the microcatheter outlet and the coagulated glue is sticky, the speed of the glue backflow on the outer wall of the microcatheter is slow, and the blood flow outside the microcatheter flows forward, which is opposite to the direction of the glue backflow, which can slow down the speed of the glue backflow outside the microcatheter, thereby preventing the glue from flowing back to the proximal release point 5, so that the operator can break and separate the microcatheter through the proximal release point 5 in this case, thereby successfully withdrawing the tube;

[0060] In order to realize the electrolysis of the distal release point 4 and the proximal release point 5 by energizing, the device further includes a first anode conductor, a second anode conductor, a cathode conductor and a power supply; one end of the first anode conductor is connected to the distal release point 4, and the other end is connected to the positive pole of the power supply; the second anode conductor is connected to the proximal release point 5, and the other end is connected to the positive pole of the power supply, so that the current output by the power supply can pass through the distal release point 4 and the proximal release point 5, thereby realizing the electrolytic splitting of the distal release point 4 and the proximal release point 5; in order to avoid the current released from the power supply passing through The first anode conductor or the second anode conductor is in direct contact with the blood. The first anode conductor and the second anode conductor are both located within the side wall of the dual-release-point electrolytic release microcatheter, thereby ensuring that the first anode conductor and the second anode conductor can respectively allow the current released from the power source to accurately pass through the distal release point 4 and the proximal release point 5; one end of the cathode conductor is fixed to the outside of the proximal catheter, the distal release point 4 or the proximal release point 5 is connected to the cathode conductor through the blood, and the other end of the cathode conductor is connected to the negative pole of the power source to achieve a circuit loop;

[0061] The existing technology uses a single release point. When injecting glue, the glue injected into the blood vessel will gradually coagulate and form a blockage, forming a gap between the catheter and the glue. If the glue injection is still continued at this time, the glue will be subjected to the pressure formed by the blockage. The glue that subsequently flows out of the catheter is forced to flow back from the gap along the outer wall of the catheter under pressure and cover the metal release point, so that the metal release point cannot contact the blood to form a current loop, and the detachable distal section and proximal section of the catheter cannot be separated, thereby causing a catheter retention accident, increasing the surgical risk; the dual-release-point electro-detachable microcatheter provided in Example 2 of the present invention, by simultaneously setting a distal release point 4 and a proximal release point 5, can effectively avoid the problem of the distal release point 4 being unable to form a circuit loop with the cathode conductor when the glue flows back, causing the microcatheter to be retained, and realize the formation of a circuit loop with the cathode conductor through the proximal release point 5, thereby breaking and separating the microcatheter at the proximal release point 5, thereby avoiding the accident of catheter retention and reducing the surgical risk.

[0062] like Figure 1 As shown, the double-release-point electrolytically detachable microcatheter provided in Example 2 of the present invention preferably comprises the distal catheter 1, the middle catheter 2 and the proximal catheter 3 each including an outer layer 01, an intermediate layer 02 and an inner layer 03. The outer layer 01 is a biocompatible polymer layer for compatibility with blood, the intermediate layer 02 is a metal reinforcement layer for supporting the shape of the microcatheter, and the inner layer 03 is a PTFE lubricating layer for preventing glue from adhering to the microcatheter.

[0063] The double-release-point electrolytically detachable microcatheter provided in Example 2 of the present invention preferably has an outer layer 01 made of a biocompatible polymer layer made of materials such as polyurethane, Pebax or Nylon, so that the outer layer 01 has good biocompatibility; the middle layer 02 can be made of a metal reinforcement layer made of materials such as 304 stainless steel, 316L stainless steel or NiTi, so that the middle layer 02 has a good supporting effect.

[0064] like Figure 1 As shown, the double-release-point electrolytically detachable microcatheter provided in Example 2 of the present invention preferably also includes two developing marks 6, which are respectively located on the distal catheter 1 and the middle catheter 2, and are used to identify the positions of the distal catheter 1 and the middle catheter 2 in the blood vessel, so as to accurately locate the position of glue discharge and determine whether the distal catheter 1 and the middle catheter 2 are broken and separated.

[0065] The dual-release-point electrolytic release microcatheter provided in Example 2 of the present invention preferably also includes two NTC thermistors. Since electrolysis is used to break the distal release point 4 or the proximal release point 5, heat will be generated. If the heat is high, it may damage the blood vessels. Therefore, it is necessary to monitor the heat generated by electrolysis. Specifically, the two NTC thermistors are respectively set at the distal release point 4 and the proximal release point 5, and the NTC thermistors are electrically connected to the power supply. When the temperature generated by electrolysis is higher than 60°C, the power supply is controlled to be cut off.

[0066] like Figures 2 to 5 As shown, the double-release-point electrolytic release microcatheter provided in Example 2 of the present invention preferably has the distal release point 4 and the proximal release point 5 both in a tubular shape in order to ensure that the outer surface and the inner cavity of the microcatheter are consistent;

[0067] Furthermore, to ensure that the microcatheter can adapt to the extension direction of the blood vessel after being inserted into the blood vessel, the distal release point 4 located deeper in the blood vessel is more flexible than the proximal release point 5. Since the curvature of the microcatheter needs to be adjusted at the distal release point 4 to adapt to the extension direction of the blood vessel, the distal release point 4 includes a first release thread 41 and a PLGA layer 42. The first release thread 41 is spirally shaped, giving the distal release point 4 good flexibility. The PLGA layer 42 is covered on the outside of the first release thread 41, making the first release thread 41 more compatible with blood.

[0068] In order to ensure that the microcatheter can be withdrawn after it breaks at the distal release point 4, the proximal release point 5 is more resilient than the distal release point 4; since the proximal release point 5 needs to withstand the stress generated by the pulling of the microcatheter, the proximal release point 5 includes a second release wire 51 and a TPU layer 52, so that the second release wire 51 is cross-woven, so that the proximal release point 5 has good resilient, and the TPU layer 52 is covered on the outside of the second release wire 51, so that the second release wire 51 has better compatibility with blood.

[0069] like Figure 6 As shown, the dual-release-point electrolytically detachable microcatheter provided in Example 2 of the present invention preferably has a plurality of grooves 4501 formed on the PLGA layer 42 and the TPU layer 52 to prevent the distal release point 4 and the proximal release point 5 from being unable to smoothly contact blood and breaking after being coated with the PLGA layer 42 and the TPU layer 52. The grooves 4501 are circumferentially arranged with the axis of the dual-release-point electrolytically detachable microcatheter as the center. By providing the grooves 4501 or pre-treating the distal release point 4 and the proximal release point 5 with cracks, the PLGA layer 42 and the TPU layer 52 can be more easily detached during electrolytic detachment, so that the distal release point 4 and the proximal release point 5 break faster, thereby improving the efficiency of tube removal.

[0070] A number of through holes 4502 are provided on the PLGA layer 42 and the TPU layer 52. The through holes 4502 connect the outer side and the inner side of the PLGA layer 42, exposing the first release thread 41 to the outside, making it easy for the first release thread 41 to come into contact with blood; similarly, the through holes 4502 connect the outer side and the inner side of the TPU layer 52, exposing the second release thread 51 to the outside, making it easy for the second release thread 51 to come into contact with blood.

[0071] like Figure 7 As shown, in the double-release-point electrolytically release microcatheter provided in Example 2 of the present invention, preferably, the cathode conductor is a diffusion stress tube 7, which is connected to the tube seat. The diffusion stress tube 7 is sleeved on the outside of the proximal catheter 3, and an insulating layer 8 is provided between the diffusion stress tube 7 and the proximal catheter 3. The diffusion stress tube 7 is connected to the negative pole of the power supply. When the diffusion stress tube 7 and the proximal catheter 3 enter the blood vessel together, the diffusion stress tube 7 can contact the blood to form a circuit loop; further, the use of the diffusion stress tube 7 sleeved on the outside of the proximal catheter 3 can avoid the conductive wire from breaking when it is inserted into the blood vessel, thereby improving the risk resistance of the microcatheter.

[0072] The double-release-point electrolysis-release microcatheter provided in Example 2 of the present invention preferably has a first anode conductor passing through the middle catheter 2, the proximal release point 5 and the proximal catheter 3, the first anode conductor is arranged in the side walls of the middle catheter 2, the proximal release point 5 and the proximal catheter 3, the second anode conductor is arranged in the side wall of the proximal catheter 3, a first switch is arranged at the connection between the first anode conductor and the power supply, and a second switch is arranged at the connection between the second anode conductor and the power supply, and the electrolysis operations of the distal release point 4 and the proximal release point 5 are respectively controlled by the same power supply; in order to realize the process of releasing the distal release point 4 first and then the proximal release point 5, the first switch is closed first, and the current electrolyzes the distal release point 4; if the distal release point 4 is covered by glue, the second switch is closed, and the current electrolyzes the proximal release point 5.

[0073] In the dual-release-point electrolytically detachable microcatheter provided in Example 2 of the present invention, preferably, the middle layer 02 can adopt one of a braided structure, a coil structure, or a hypotube structure, or a combination of multiple structures, such as a braided structure on the outer side and a coil structure on the inner side. By adopting the above structures, the microcatheter can have better pushability, flexibility, tracking, kink resistance, and support, thereby ensuring safe and effective surgery.

[0074] When the intermediate layer 02 is made of a braided structure, several, for example, eight, of the first anode conductor, the second anode conductor, and the third anode conductor can be selected from a plurality of braided wires and used as conductive wires.

[0075] To sum up, the double-release-point electrolytically detachable microcatheter provided by the present invention can solve the problem in the prior art that when injecting glue, the glue injected into the blood vessel will gradually coagulate to form a blockage, forming a gap between the glue and the catheter. At this time, if the glue injection continues, the glue will be subjected to the pressure formed by the blockage, and the glue subsequently flowing out of the catheter will be forced to flow back from the gap along the outer wall of the catheter under pressure, and cover the metal release point, so that the metal release point cannot contact the blood to form an electric current loop, and the detachable distal section and the proximal section of the catheter cannot be separated, thereby causing catheter retention accidents and increasing surgical risks. The invention can avoid accidents of catheter retention due to glue backflow and reduce surgical risks.

[0076] Those skilled in the art should understand that they can implement the above-mentioned variations by combining the existing technology and the above-mentioned embodiments, which will not be described in detail here. Such variations do not affect the essence of the present invention and will not be described in detail here.

[0077] The above describes the preferred embodiments of the present invention. It should be understood that the present invention is not limited to the above-mentioned specific embodiments, and the devices and structures that are not described in detail should be understood to be implemented in a common manner in the art; any technician familiar with the art can make many possible changes and modifications without departing from the technical solution of the present invention, or modify them into equivalent embodiments with equivalent changes, which does not affect the essential content of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention that do not depart from the content of the technical solution of the present invention are still within the scope of protection of the technical solution of the present invention.

Claims

1. A double-release-point electrolytic release microcatheter, characterized in that: It comprises a distal catheter, a middle catheter and a proximal catheter; the proximal end of the distal catheter is connected to the distal end of the middle catheter, and a distal release point is provided at the connection; the proximal end of the middle catheter is connected to the distal end of the proximal catheter, and a proximal release point is provided at the connection; Also included are a first anode conductor, a second anode conductor, a cathode conductor, and a power source; The first anode conductor and the second anode conductor are both located in the side wall of the double-release-point electrolytic release microcatheter; One end of the first anode conductor is connected to the distal release point, and the other end is connected to the positive pole of the power supply; the second anode conductor is connected to the proximal release point, and the other end is connected to the positive pole of the power supply; one end of the cathode conductor is fixed to the outside of the proximal catheter, and the other end is connected to the negative pole of the power supply.

2. The dual-release-point electrolytic release microcatheter according to claim 1, wherein: The distal catheter, the middle catheter and the proximal catheter all include an outer layer, an intermediate layer and an inner layer; the outer layer is a biocompatible polymer layer; the intermediate layer is a metal reinforcement layer; and the inner layer is a PTFE lubricating layer.

3. The dual-release-point electrolytic release microcatheter according to claim 2, wherein: The outer layer is made of polyurethane, Pebax or Nylon; the middle layer is made of 304 stainless steel, 316L stainless steel or NiTi.

4. The dual-release-point electrolytic release microcatheter according to claim 1, wherein: It also includes two visualization marks; the two visualization marks are respectively located on the distal catheter and the middle catheter.

5. The dual-release-point electrolytic release microcatheter according to claim 1, wherein: It also includes two NTC thermistors; the two NTC thermistors are respectively arranged at the distal release point and the proximal release point; and the NTC thermistors are electrically connected to the power supply.

6. The dual-release-point electrolytic release microcatheter according to claim 1, wherein: The distal release point includes a first release thread and a PLGA layer; the first release thread is spiral; the PLGA layer covers the outside of the first release thread; The proximal release point includes a second release thread and a TPU layer; the second release thread is cross-woven; and the TPU layer covers the outside of the second release thread.

7. The dual-release-point electrolytic release microcatheter according to claim 6, wherein: A plurality of grooves are provided on the PLGA layer and the TPU layer; the grooves are arranged circumferentially with the axis of the double-release-point electrolytic release microcatheter as the center; A plurality of through holes are formed on the PLGA layer and the TPU layer.

8. The dual-release-point electrolytic release microcatheter according to claim 1, wherein: The cathode conductor is a diffusion stress tube; the diffusion stress tube is sleeved on the outside of the proximal section conduit; an insulating layer is provided between the diffusion stress tube and the proximal section conduit; and the diffusion stress tube is connected to the negative pole of the power supply.

9. The dual-release-point electrolytic release microcatheter according to claim 8, wherein: Also included is a third anode conductor; The first anode conductor is disposed in the side wall of the middle section conduit; the second anode conductor is disposed in the side wall of the proximal section conduit; and the third anode conductor is disposed in the side wall of the distal section conduit; The first anode conductor and the second anode conductor are respectively connected to two ends of the proximal release point; The second anode conductor and the third anode conductor are connected to two ends of the distal release point, respectively.

10. The dual-release-point electrolytic release microcatheter according to claim 8, wherein: The first anode conductor passes through the mid-section catheter, the proximal release point and the proximal section catheter; The first anode conductor is arranged in the side wall of the middle section catheter, the proximal release point and the proximal section catheter; the second anode conductor is arranged in the side wall of the proximal section catheter.

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