Side hole drug infusion microcatheter

Abstract

This invention discloses a side-hole drug infusion microcatheter, comprising: a catheter. The catheter has an embolization channel, an infusion channel, a guiding channel, and multiple through holes. The embolization channel, infusion channel, and guiding channel are arranged radially and isolated from each other. The infusion channel surrounds the periphery of the embolization channel. The guiding channel extends in the same direction as the catheter and is used for the insertion of a microguidewire into the body. The multiple through holes are located on the side wall of the catheter. The catheter integrates embolization delivery and drug infusion functions into a single device, eliminating the need to change the catheter during procedures due to function switching, fundamentally avoiding repeated mechanical stimulation of the vascular intima caused by multiple device exchanges. The combination of the infusion channel and the circumferentially distributed through holes allows the infused drug to be uniformly dispersed in the target area. The guiding channel provides a stable insertion path for the microguidewire, making the catheter push and positioning process smoother and reducing the need for repeated device adjustments.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a side-hole drug infusion microcatheter. Background Technology

[0002] Severe intracranial venous sinus thrombosis often leads to serious consequences, even death. Currently, after anticoagulation therapy fails, patients with severe intracranial venous sinus thrombosis often undergo neurointerventional treatment, such as intracranial venous sinus stent thrombectomy, intracranial venous sinus aspiration thrombectomy, or intracranial venous sinus balloon dilation. Because the thrombus burden of intracranial venous sinus thrombosis is generally much greater than that of arterial thrombosis, it is difficult to completely remove the thrombus from the intracranial venous sinus regardless of the mechanical thrombectomy method used. Therefore, after thrombectomy, a neurointerventional microcatheter is usually left in the intracranial venous sinus (in vivo). A microinfusion pump is connected to the end of the microcatheter (outside the body), and thrombolytic drugs are continuously infused intravenously through the microcatheter for approximately 72-60 hours to maximize the dissolution of the thrombus in the intracranial venous sinus, thereby improving intracranial venous sinus blood circulation, ultimately improving the patient's clinical symptoms, and reducing mortality and disability.

[0003] During embolization, if the tip of the microcatheter adheres to the vessel wall due to embolization adhesive residue or solidification, the pulling force applied along its long axis during catheter withdrawal will be directly transmitted to the local intimal contact surface through the catheter tip. The magnitude and direction of this force are influenced by multiple factors, including adhesion strength, withdrawal speed, and the relative angle between the catheter and the vessel wall. When the withdrawal path deviates from the natural course of the vessel, the axial tension will decompose into a tearing component perpendicular to the vessel wall and a shearing component along the vessel wall, which together constitute a composite load on the vessel wall structure. If the stress level exceeds the inherent tolerance threshold of the tissue, it can lead to intimal flap formation, medial delamination, or full-thickness rupture, ultimately manifesting as serious vascular events such as vascular dissection, pseudoaneurysm, or perforation. Once such damage occurs, it significantly increases the overall risk of intraoperative and postoperative vascular-related complications. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, the present invention aims to provide a side-port drug infusion microcatheter, which reduces damage to blood vessels during surgery. It also aims to reduce the likelihood of blockage in single-port catheters.

[0005] The objective of this invention is achieved through the following technical solution:

[0006] A side-hole drug infusion microcatheter, comprising:

[0007] The catheter has an embolization channel, an infusion channel, a guide channel, and multiple through holes. The embolization channel, the infusion channel, and the guide channel are arranged radially isolated from each other. The embolization channel extends in the same direction as the catheter. The infusion channel is arranged around the periphery of the embolization channel. The guide channel extends in the same direction as the catheter and is used for the insertion of a microguidewire into the human body. The multiple through holes are located on the sidewall of the catheter and are distributed circumferentially around the catheter. The through holes connect the infusion channel to the external environment and are used to allow the infused drug to exit the catheter.

[0008] Furthermore, the infusion channel includes a dispensing chamber and a diversion channel, which are distributed at intervals along the length of the embolic agent channel; the diversion channel is provided with multiple baffles, which are arranged at intervals around the circumference of the diversion channel to divide the diversion channel into multiple unit infusion channels; both ends of each unit infusion channel are respectively connected to the dispensing chamber and at least one of the through holes; the dispensing chamber contains a selection mechanism, which is used to selectively connect the dispensing chamber and at least one of the diversion channels.

[0009] Furthermore, the selection mechanism includes a conversion ring located at the junction of the dispensing chamber and the diversion channel. The conversion ring has an opening for connecting the dispensing chamber and at least one of the unit injection channels.

[0010] Furthermore, the outer wall of the conversion ring is provided with a plurality of first magnetic elements, and the outer wall of the conduit is rotatably fitted with a sleeve. The inner wall of the sleeve is provided with a plurality of second magnetic elements, and the second magnetic elements are magnetically attracted to the first magnetic elements so that the conversion ring rotates with the sleeve.

[0011] Furthermore, the outer contour of the opening is the same as the outer contour of the unit injection channel and the two have equal cross-sectional areas. When the first magnetic component and the second magnetic component remain stationary, the opening completely overlaps with one of the unit injection channels.

[0012] Furthermore, the end of the catheter for insertion into the human body is provided with a separable component, one end of the embolic agent channel is located on the separable component, and one end of the guide channel is located on the separable component; the separable component is detachably connected to the catheter via a locking release mechanism.

[0013] Furthermore, the locking release mechanism includes a first channel, a second channel, and a locking member. The first channel is disposed in the catheter, and the second channel is disposed in the separable member. The locking member is slidably connected to the first channel and the second channel so that the locking member can be simultaneously inserted into the first channel and the second channel to prevent the separable member from separating from the catheter. Also, the locking member can disengage from the first channel or the second channel to allow the separable member from separating from the catheter.

[0014] Furthermore, the end of the second channel away from the first channel is connected to the guide channel; the locking release mechanism also includes a coil spring and a gear, the conduit is provided with a receiving cavity communicating with the first channel, the receiving cavity accommodating the coil spring and the gear, the locking member is provided with a plurality of meshing teeth that cooperate with the gear, the plurality of meshing teeth being spaced apart along the extension direction of the locking member, the gear meshing with the locking member; one end of the coil spring is fixedly connected to the inner wall of the receiving cavity; the other end of the coil spring is connected to the gear, so that the gear has a tendency to drive the locking member to rotate away from the second channel; a micro guide wire passes through the guide channel, the micro guide wire preventing the locking member from entering the guide channel, and when the micro guide wire is withdrawn from the guide channel, the locking member leaves the second channel to release the obstruction state of the separable member.

[0015] Furthermore, the separable component is made of a developing material.

[0016] Furthermore, the separable member is provided with a drug cavity containing a drug; when the separable member is separated from the catheter, the drug in the drug cavity is released.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1. The embolic agent channel, the infusion channel, and the guiding channel are arranged radially isolated from each other along the catheter, with the embolic agent channel extending in the same direction as the catheter. By independently configuring the embolic agent channel, in the event of embolic agent adhesion, the catheter withdrawal force is confined within this channel structure, effectively reducing the transmission of the pulling force to the vessel wall and minimizing the risk of vascular injury or tearing.

[0019] 2. Based on the infusion channel and surrounding the periphery of the embolic agent channel; multiple through holes are provided on the sidewall of the catheter and distributed circumferentially around the catheter. The through holes connect the infusion channel to the external environment and are used to allow the infused drug to exit the catheter. The cooperation between the infusion channel and the circumferentially distributed through holes allows the infused drug to be uniformly dispersed in the target area, avoiding excessively high local concentrations and uneven infusion caused by single-point injection, thus improving the accuracy and safety of drug action.

[0020] 3. Since the guiding channel extends in the same direction as the catheter, it is used for the insertion of a microguidewire into the body. The guiding channel provides a stable insertion path for the microguidewire, making catheter advancement and positioning smoother and reducing the need for repeated instrument adjustments. Overall, this catheter, through structural integration and functional separation, significantly reduces the mechanical impact of surgical procedures on blood vessels, improving the safety of embolization treatment. The catheter integrates embolic agent delivery and drug infusion functions into a single device, eliminating the need to change catheters during procedures due to functional switching, fundamentally avoiding repeated mechanical stimulation of the vascular endothelium caused by multiple instrument exchanges. Attached Figure Description

[0021] Figure 1 This is a schematic diagram of the structure of the side-hole drug infusion microcatheter of the present invention;

[0022] Figure 2 for Figure 1 The sectional view shown;

[0023] Figure 3 for Figure 2 A magnified view of point A shown below;

[0024] Figure 4 for Figure 1 The sectional view shown.

[0025] In the diagram: 1. Conduit; 2. Embolizing agent channel; 3. Infusion channel; 4. Guide channel; 5. Through hole; 6. Dispensing chamber; 7. Baffle; 8. Unit infusion channel; 9. Converter ring; 10. Opening; 11. First magnetic component; 12. Sleeve; 13. Second magnetic component; 14. Separable component; 15. First channel; 16. Second channel; 17. Locking component; 18. Coil spring; 19. Gear; 20. Receiving cavity; 21. Meshing teeth. Detailed Implementation

[0026] The present invention will now be further described in conjunction with the accompanying drawings and specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.

[0027] It should be noted that when an element is described as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is described as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementations.

[0028] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0029] See Figures 1-4 A preferred embodiment of the present invention provides a side-hole drug infusion microcatheter 1, comprising: a catheter 1.

[0030] The catheter 1 is provided with an embolization channel 2, an infusion channel 3, a guide channel 4, and multiple through holes 5. The embolization channel 2, the infusion channel 3, and the guide channel 4 are arranged radially isolated from each other along the catheter 1. The embolization channel 2 extends in the same direction as the catheter 1. The infusion channel 3 is arranged around the periphery of the embolization channel 2. The guide channel 4 extends in the same direction as the catheter 1. The guide channel 4 is used for the insertion of a microguidewire into the human body. Multiple through holes 5 are provided on the side wall of the catheter 1 and are distributed circumferentially around the catheter 1. The through holes 5 connect the infusion channel 3 to the external environment and are used to allow the infused drug to exit the catheter 1.

[0031] The embolic agent channel 2 extends in the same direction as catheter 1, allowing unidirectional passage of the embolic agent to avoid mixing or interference between the embolic agent and the infused medication. It also ensures an independent flow path for the embolic agent during delivery, reducing the risk of catheter 1 being pulled due to embolic agent viscosity. The infusion channel 3 surrounds the embolic agent channel 2, with multiple through-holes 5 located on the sidewall of catheter 1 and spaced circumferentially around it. These through-holes 5 connect the infusion channel 3 to the external environment. After being delivered through the infusion channel 3, the infused medication can exit catheter 1 through the through-holes 5, achieving diffuse release of the medication in the target area. The guide channel 4 extends in the same direction as catheter 1, allowing the insertion of a microguidewire into the body. This ensures that catheter 1 maintains a stable axial direction during pushing and positioning, reducing the need for repeated adjustments and device exchanges. The catheter 1 can simultaneously deliver embolic material and infuse endothelialization-promoting drugs into the aneurysm neck region through the perforation port 5 to aid healing. It can also deliver embolic agents to occlude malformed vascular nests while simultaneously infusing vascular protective drugs into the surrounding normal vascular bed through the perfusion channel 3 to reduce the sequelae of misembolization. Furthermore, it can infuse chemotherapy drugs into the surrounding tissue through the perforation port 5 while performing embolization of the tumor-feeding arteries to increase local drug concentration and reduce systemic toxicity. This catheter 1 integrates embolic agent delivery and drug infusion functions into a single device, eliminating the need to replace catheter 1 during embolization procedures to switch between infusion and embolization. This avoids mechanical irritation to the vascular intima caused by repeated device exchanges and also reduces the risk of vascular damage due to catheter withdrawal traction.

[0032] Working Principle: Based on its internally isolated multi-cavity structure and sidewall through-holes 5, this device enables parallel operation of embolic agent delivery and drug infusion within the same device. The embolic agent channel 2 forms an independent unidirectional embolic agent delivery path, preventing mixing or interference between the embolic agent and the infused drug. After being delivered via the infusion channel 3, the infused drug exits the catheter 1 through the through-holes 5, achieving diffuse release of the drug in the target area. The guiding channel 4 extends in the same direction as the catheter 1, used for microguidewire insertion, maintaining the stability of the catheter 1 axis during advancement and positioning, reducing repeated device adjustments and exchanges. This catheter 1 integrates embolic agent delivery and drug infusion functions, eliminating the need to replace the catheter 1 during switching operations, avoiding mechanical stimulation of the vascular endothelium from multiple device exchanges, and reducing the risk of vascular injury caused by catheter withdrawal traction.

[0033] Clearly, this catheter 1 integrates embolization agent delivery and drug infusion functions into a single device, eliminating the need to replace catheter 1 during procedures to switch functions, fundamentally avoiding repeated mechanical stimulation of the vascular endothelium caused by multiple device exchanges. Through the independent design of the embolization agent channel 2, in the event of embolization agent adhesion, the withdrawal traction force is confined within this channel structure, effectively reducing the transmission of traction force to the vessel wall and minimizing the risk of vascular injury or tearing. The cooperation between the infusion channel 3 and the circumferentially distributed through-holes 5 allows for uniform diffusion of the infused drug in the target area, avoiding excessively high local concentrations and uneven perfusion overlap caused by single-point spraying, thus improving the accuracy and safety of drug action. The guiding channel 4 provides a stable path for the microguidewire, making the advancement and positioning of catheter 1 smoother and reducing the need for repeated device adjustments. Overall, this catheter 1, through structural integration and functional separation, significantly reduces the mechanical impact of surgical procedures on the blood vessel, improving the safety of embolization treatment.

[0034] In this embodiment, preferably, the infusion channel 3 includes a dispensing chamber 6 and a diversion channel, the dispensing chamber 6 and the diversion channel being distributed at intervals along the length of the embolic agent channel 2; the diversion channel is provided with multiple baffles 7, which are arranged at intervals around the circumference of the diversion channel to divide the diversion channel into multiple unit infusion channels 8; each unit infusion channel 8 is connected at both ends to the dispensing chamber 6 and at least one of the through holes 5; the dispensing chamber 6 contains a selection mechanism, which is used to selectively connect the dispensing chamber 6 and at least one of the diversion channels. The selection mechanism is housed in the dispensing chamber 6 and can selectively connect the dispensing chamber 6 to one or more diversion channels according to treatment needs, thereby controlling the release of the drug only through the unit infusion channels 8 and through holes 5 in a specific direction. For example, in intracranial aneurysm embolization, a single perfusion channel 8 can be opened only towards the aneurysm neck to precisely infuse endothelialization drugs into the aneurysm neck region to promote healing. In cerebral arteriovenous malformation embolization, a channel can be selected that avoids the direction of the malformed vascular nest to infuse vascular protective drugs only into the surrounding normal vascular bed to reduce the sequelae of misembolization. In preoperative embolization of highly vascularized tumors, multiple single perfusion channels 8 can be opened towards the branches of the tumor-feeding arteries to simultaneously infuse chemotherapy drugs into multiple target areas to increase local drug concentration and reduce systemic toxicity. This structure allows for selective control of the release direction, range, and area of ​​the infused drugs according to the lesion morphology and treatment needs, avoiding ineffective diffusion or mis-infusion of drugs into non-target areas, and improving the precision and safety of drug action during embolization therapy.

[0035] In this embodiment, preferably, the selection mechanism includes a conversion ring 9, which is located at the junction of the dispensing chamber 6 and the diversion channel. The conversion ring 9 has an opening 10 for connecting the dispensing chamber 6 and at least one of the unit infusion channels 8. The conversion ring 9 in the selection mechanism, located at the junction of the dispensing chamber 6 and the diversion channel, has an opening 10. By rotating the conversion ring 9, the opening 10 can selectively connect the dispensing chamber 6 to at least one unit infusion channel 8. After the infused drug enters the dispensing chamber 6, it only passes through the unit infusion channel 8 corresponding to the opening 10 of the conversion ring 9, and is then directionally released through the through-hole 5 connected to the unit infusion channel 8, achieving precise selection of the direction and range of drug release. In terms of structural implementation, the opening 10 of the conversion ring 9 can be configured as a single arc-shaped notch to connect only a single unit perfusion channel 8 for precise unidirectional perfusion; alternatively, the opening 10 of the conversion ring 9 can be configured as multiple spaced arc-shaped notches to simultaneously connect multiple non-adjacent unit perfusion channels 8 for synchronous perfusion in multiple regions. This structure, through the configuration of the shape and number of openings 10 in the conversion ring 9, achieves directional and controllable release of the perfused drug in multiple independent circumferential channels, avoiding ineffective diffusion of the drug into non-target areas and improving the accuracy and operational flexibility of drug perfusion during embolization therapy.

[0036] In this embodiment, preferably, the outer wall of the switching ring 9 is provided with a plurality of first magnetic elements 11, and the outer wall of the conduit 1 is rotatably fitted with a sleeve 12. The inner wall of the sleeve 12 is provided with a plurality of second magnetic elements 13. The second magnetic elements 13 are magnetically attracted to the first magnetic elements 11, so that the switching ring 9 rotates with the sleeve 12. When the operator rotates the sleeve 12, the torque is transmitted to the switching ring 9 through the magnetic field. There is no need to set any mechanical transmission components inside the conduit 1, thereby avoiding the space occupation of the dispensing chamber 6, the diversion channel and the unit perfusion channel 8 by the transmission structure, ensuring the continuity and smoothness of the inner wall of the perfusion channel 3, and reducing fluid resistance and the risk of thrombus adhesion. The magnetic coupling method eliminates the possibility of particle shedding caused by friction in mechanical transmission, and prevents foreign objects from entering the perfusion channel 3 or the blood system. The first magnetic elements 11 and the second magnetic elements 13 can be arranged symmetrically at multiple points to make the magnetic attraction force evenly distributed, ensuring that the switching ring 9 remains synchronized with the sleeve 12 at any rotation angle without deviation. The first magnetic component 11 and the second magnetic component 13 can be made of high-temperature sterilizable permanent magnet materials, allowing the entire catheter 1 to be repeatedly sterilized without affecting coupling performance. The first magnetic component 11 and the second magnetic component 13 can also be arranged in a staggered manner along the axial direction, maintaining the stability of magnetic coupling even when the catheter 1 is subjected to axial tension, thus avoiding drive failure due to slight displacement. This structure achieves remote and precise control of the conversion ring 9 through magnetic coupling, ensuring drive reliability while avoiding interference from the mechanical transmission structure to the internal lumen of the catheter 1, thereby improving operational safety and structural integrity.

[0037] In this embodiment, preferably, the outer contour of the opening 10 is the same as the outer contour of the unit infusion channel 8, and their cross-sectional areas are equal. When the first magnetic component 11 and the second magnetic component 13 remain stationary, the opening 10 completely overlaps with one of the unit infusion channels 8. In the stationary state, the opening 10 and the target unit infusion channel 8 form a precise docking without offset, ensuring that the flow channel cross-section remains continuous and consistent when the infused drug enters the unit infusion channel 8 from the dispensing chamber 6. This avoids turbulence, eddies, and pressure loss caused by abrupt changes or misalignments in the cross-section, ensuring the stability of the flow field and the accuracy of the flow rate during drug delivery. The complete overlap between the opening 10 and the channel eliminates the possibility of cross-flow between adjacent channels, preventing lateral leakage or accidental entry of the drug into non-target channels at the junction of the conversion ring 9 and the diversion channel, thereby achieving complete isolation between each unit infusion channel 8. The first magnetic component 11 and the second magnetic component 13 can be configured in even pairs and distributed at equal angles along the circumference, so that the conversion ring 9 can automatically return to a stable position where the opening 10 and the unit infusion channel 8 are completely aligned by magnetic attraction at each positioning point. This structure, through the consistent cross-sectional design of the opening 10 and the channel, combined with the magnetic positioning mechanism, achieves precise docking and sealing isolation of the flow channel in the selected state of the infusion channel 3, improving the accuracy of drug infusion direction selection and delivery stability.

[0038] In this embodiment, preferably, the end of the catheter 1 for insertion into the human body is provided with a separable member 14. One end of the embolic agent channel 2 is located at the separable member 14, and one end of the guide channel 4 is located at the separable member 14. The separable member 14 is detachably connected to the catheter 1 via a locking release mechanism. When the embolization operation is completed or the embolic agent adheres to the front end of the catheter 1, the operator can separate the separable member 14 from the catheter 1 body through the locking release mechanism, allowing the catheter 1 body to be safely withdrawn, while the separable member 14 remains in the target blood vessel as part of the embolization structure, avoiding the direct action of the traction force generated by forced catheter withdrawal on the blood vessel wall. In terms of structural implementation, the locking release mechanism can adopt a structure of mechanical buckle and traction wire cooperation, where the buckle is disengaged by external traction of the traction wire to achieve controlled release of the separable member 14; the locking release mechanism can also adopt an electrolytic release structure, where electrolytic corrosion of the connection point is achieved by applying an electrolytic current; the locking release mechanism can also adopt a thermal fusion release structure, where the fusible material of the connection point is melted by heating to achieve separation. The active release mechanism of the separable component 14 when embolization is completed or adhesion occurs effectively isolates the mechanical traction force that may be generated during catheter removal from the blood vessel wall, avoiding the risk of intimal tearing or damage caused by difficulty in catheter removal.

[0039] In this embodiment, preferably, the locking release mechanism includes a first channel 15, a second channel 16, and a locking member 17. The first channel 15 is disposed in the catheter 1, and the second channel 16 is disposed in the separable member 14. The locking member 17 is slidably connected to the first channel 15 and the second channel 16, so that the locking member 17 can simultaneously pass through the first channel 15 and the second channel 16 to prevent the separable member 14 from separating from the catheter 1; and the locking member 17 can disengage from either the first channel 15 or the second channel 16 to allow the separable member 14 to separate from the catheter 1. During the embolization operation, the locking member 17 simultaneously passes through the catheter 1 and the separable member 14, forming a mechanical locking connection, so that the separable member 14 and the catheter 1 body remain in a stable integrated state, ensuring the reliability of embolic agent delivery and catheter 1 controllability; when it is necessary to release the separable member 14, the locking member 17 is slidably disengaged along the channel through external operation, realizing the controllable separation of the separable member 14 from the catheter 1, avoiding damage to the blood vessel wall caused by forced traction. The locking element 17 can be a pin with a traction wire, which extends from the inside of the catheter 1 to the outside of the body. Pulling the traction wire causes the pin to exit the second channel 16, achieving separation. Alternatively, the locking element 17 can be an elastic claw structure, with a groove on the inner wall of the first channel 15 that engages with the claw. The traction wire unlocks the claw, causing it to disengage from the groove. The locking element 17 can also be a flexible wire folded into a loop structure, with the wire inserted after the first channel 15 and the second channel 16 are aligned. Removing the wire releases the lock. This structure, through the sliding insertion and withdrawal mechanism of the locking element 17, achieves the controllable release of the separable element 14, allowing for smooth separation of the catheter 1 from the indwelling portion when needed, avoiding the transmission of mechanical pulling force to the vessel wall during catheter removal.

[0040] In this embodiment, preferably, the end of the second channel 16 away from the first channel 15 is connected to the guide channel 4; the locking release mechanism further includes a coil spring 18 and a gear 19, the conduit 1 is provided with a receiving cavity 20 communicating with the first channel 15, the receiving cavity 20 accommodating the coil spring 18 and the gear 19, the locking member 17 is provided with a plurality of meshing teeth 21 cooperating with the gear 19, the plurality of meshing teeth 21 being spaced apart along the extension direction of the locking member 17, the gear 19 meshing with the locking member 17; one end of the coil spring 18 is fixedly connected to the inner wall of the receiving cavity 20; the other end of the coil spring 18 is connected to the gear 19, so that the gear 19 has a tendency to drive the locking member 17 to rotate away from the second channel 16; a microguide wire is passed through the guide channel 4, the microguide wire preventing the locking member 17 from entering the guide channel 4, when the microguide wire is withdrawn from the guide channel 4, the locking member 17 leaves the second channel 16 to release the blocking state of the separable member 14. The locking and releasing mechanism connects the end of the second channel 16 furthest from the first channel 15 to the guide channel 4, causing the movement path of the locking member 17 to intersect with the insertion path of the microguidewire. When the microguidewire is inserted into the guide channel 4, it directly blocks the locking member 17 from entering the guide channel 4, thereby maintaining the locking member 17 in a locked state where it is inserted into both the first channel 15 and the second channel 16, ensuring a stable connection between the separable member 14 and the catheter 1 during the embolization operation. When the operator completes the embolization operation or needs to release the separable member 14, they only need to remove the microguidewire according to the normal operating procedure. After the microguidewire is removed, the blocking effect disappears, and the coil spring 18 drives the locking member 17 to rotate automatically and disengage from the second channel 16 via the gear 19, thereby releasing the lock on the separable member 14. Based on this structure, the locking and release operation and the microguidewire withdrawal action are automatically linked, eliminating the need for the operator to perform additional unlocking steps. This avoids misoperation or delays caused by increased complexity in intraoperative procedures. Simultaneously, the coil spring 18 and gear 19 work together to ensure rapid and definite disengagement of the locking element 17, eliminating incomplete or delayed release that may occur with manual unlocking. This structure, through the coordination of the microguidewire as a temporary barrier and the drive mechanism, precisely links the locking and release timing of the separable element 14 to the presence of the microguidewire. This allows the operator to automatically prepare for the release of the separable element 14 without needing to pay extra attention to the unlocking process when withdrawing the microguidewire, reducing the cognitive burden and operational steps during the procedure. It also avoids mechanical traction damage to the vessel wall caused by forcibly withdrawing the catheter due to forgetting to unlock.

[0041] In this embodiment, preferably, the separable component 14 is made of a radiopaque material. The radiopaque material ensures the separable component 14 is clearly visible under medical imaging equipment. During catheter 1 advancement, the operator can confirm the relative position of the separable component 14 and the catheter 1 body in real time via imaging, ensuring the separable component 14 accurately reaches the target blood vessel area before embolization. When the locking release mechanism is locked, the connection interface between the separable component 14 and the catheter 1 body is clearly visible under imaging, facilitating operator confirmation of the locking status. When the microguidewire is withdrawn and the locking release mechanism is released, the separable component 14 and the catheter 1 body are separated under imaging, allowing the operator to visually confirm that the separable component 14 has been successfully placed in the predetermined position, at which point the catheter 1 body can be safely withdrawn. During postoperative follow-up, the separable component 14, due to its radiopaque properties, can be clearly located in imaging re-examination, facilitating long-term assessment of the stability of the placement position and changes in surrounding tissues. The separable component 14 can be made entirely of a platinum and tungsten alloy composite material, ensuring both radiopaqueness and biocompatibility. This structure, through the imaging properties of the separable element 14 itself, allows the operator to obtain intuitive image feedback at each stage of locking and maintaining, releasing decision, post-release confirmation, and postoperative follow-up, thereby improving the accuracy and reliability of the separable element 14 placement operation.

[0042] In this embodiment, preferably, the separable member 14 is provided with a drug cavity containing a drug; when the separable member 14 is separated from the catheter 1, the drug in the drug cavity is released. While the separable member 14 is placed in the target blood vessel, the drug in the drug cavity can be locally released at the placement site, allowing embolization treatment and local drug treatment to be completed simultaneously in the same operation, without the need for additional drug delivery via other devices. The drug in the drug cavity is released only after the separable member 14 is separated from the catheter 1, avoiding premature leakage or dilution of the drug during delivery and ensuring the accuracy of drug concentration and dosage at the target location. Structurally, the drug cavity can adopt a microencapsulation structure, encapsulating the drug in biodegradable polymer microcapsules. After the separable member 14 is placed, the microcapsules gradually degrade under the action of body fluids to achieve sustained drug release; alternatively, the drug cavity can adopt a diaphragm-sealed structure, with the drug cavity outlet sealed by a soluble diaphragm. After separation, the diaphragm dissolves upon contact with body fluids, thereby releasing the drug. By integrating the drug chamber into the separable component 14, the placement of the embolization material and the release of the drug are completed simultaneously at the same location, realizing an integrated operation of local treatment and avoiding repeated stimulation of the blood vessel wall caused by multiple instrument interventions.

[0043] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of those different embodiments or examples.

[0044] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0045] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various variations or substitutions within the technical scope disclosed in this application, and these should all be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A side-hole drug infusion microcatheter, characterized in that, include: The catheter (1) is provided with an embolization channel (2), an infusion channel (3), a guide channel (4) and multiple through holes (5). The embolization channel (2), the infusion channel (3) and the guide channel (4) are arranged radially isolated from each other along the catheter (1). The embolization channel (2) extends in the same direction as the catheter (1). The infusion channel (3) is arranged around the periphery of the embolization channel (2). The guide channel (4) extends in the same direction as the catheter (1). The guide channel (4) is used for the insertion of a microguidewire into the human body. Multiple through holes (5) are provided on the side wall of the catheter (1) and are distributed circumferentially around the catheter (1). The through holes (5) connect the infusion channel (3) and the external environment and are used for the infused drug to leave the catheter (1).

2. The side-hole drug infusion microcatheter according to claim 1, characterized in that, The infusion channel (3) includes a dispensing chamber (6) and a diversion channel, which are distributed at intervals along the length of the embolic agent channel (2). The diversion channel is provided with multiple baffles (7), which are arranged at intervals around the circumference of the diversion channel to divide the diversion channel into multiple unit infusion channels (8). The two ends of each unit infusion channel (8) are respectively connected to the dispensing chamber (6) and at least one of the through holes (5). The dispensing chamber (6) contains a selection mechanism for selectively connecting the dispensing chamber (6) and at least one of the diversion channels.

3. The side-hole drug infusion microcatheter according to claim 2, characterized in that, The selection mechanism includes a switching ring (9) located at the junction of the liquid distribution chamber (6) and the diversion channel. The switching ring (9) has an opening (10) for connecting the liquid distribution chamber (6) and at least one of the unit injection channels (8).

4. The side-hole drug infusion microcatheter according to claim 3, characterized in that, The outer wall of the conversion ring (9) is provided with a plurality of first magnetic elements (11), and the outer wall of the conduit (1) is rotatably fitted with a sleeve (12). The inner wall of the sleeve (12) is provided with a plurality of second magnetic elements (13). The second magnetic elements (13) are magnetically attracted to the first magnetic elements (11) so that the conversion ring (9) rotates with the sleeve (12).

5. A side-hole drug infusion microcatheter according to claim 4, characterized in that, The cross-sectional outer contour of the opening (10) is the same as the cross-sectional outer contour of the unit injection channel (8) and the cross-sectional area of ​​the two are equal. When the first magnetic element (11) and the second magnetic element (13) remain stationary, the opening (10) completely overlaps with one of the unit injection channels (8).

6. The side-hole drug infusion microcatheter according to claim 1, characterized in that, The catheter (1) has a separable part (14) at the end for insertion into the human body. One end of the embolic agent channel (2) is located on the separable part (14), and one end of the guide channel (4) is located on the separable part (14). The separable part (14) is detachably connected to the catheter (1) by a locking release mechanism.

7. A side-hole drug infusion microcatheter according to claim 6, characterized in that, The locking release mechanism includes a first channel (15), a second channel (16), and a locking member (17). The first channel (15) is disposed on the conduit (1), and the second channel (16) is disposed on the detachable member (14). The locking member (17) is slidably connected to the first channel (15) and the second channel (16) so that the locking member (17) can be simultaneously inserted into the first channel (15) and the second channel (16) to prevent the detachable member (14) and the conduit (1) from separating. The locking member (17) can also disengage from the first channel (15) or the second channel (16) to allow the detachable member (14) and the conduit (1) to separate.

8. A side-hole drug infusion microcatheter according to claim 7, characterized in that, The second channel (16) is connected to the guide channel (4) at one end away from the first channel (15); the locking release mechanism also includes a coil spring (18) and a gear (19). The guide tube (1) is provided with a receiving cavity (20) communicating with the first channel (15). The receiving cavity (20) accommodates the coil spring (18) and the gear (19). The locking member (17) is provided with a plurality of meshing teeth (21) that cooperate with the gear (19). The plurality of meshing teeth (21) are spaced apart along the extension direction of the locking member (17). The gear (19) and the locking member (18) are connected to the guide channel (4). 7) Engagement; one end of the coil spring (18) is fixedly connected to the inner wall of the receiving cavity (20); the other end of the coil spring (18) is connected to the gear (19) so that the gear (19) has a tendency to drive the locking member (17) to rotate away from the second channel (16); the guide channel (4) is provided with a micro guide wire, which blocks the locking member (17) from entering the guide channel (4). When the micro guide wire is pulled out of the guide channel (4), the locking member (17) leaves the second channel (16) to release the blocking state of the separable member (14).

9. A side-hole drug infusion microcatheter according to claim 6, characterized in that, The separable component (14) is made of developing material.

10. A side-hole drug infusion microcatheter according to claim 6, characterized in that, The separable member (14) is provided with a drug cavity containing a drug; when the separable member (14) is separated from the catheter (1), the drug in the drug cavity is released.

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