A biliary drainage tube capable of end-face implantation of radioactive particles

Abstract

The application discloses a biliary drainage tube with end face implanted radioactive particles, which comprises a catheter and an end connecting assembly, and an internal main drainage channel and at least one particle channel are arranged axially in the catheter, the particle channel is used for loading radioactive particles, a bendable pigtail section is arranged at the front end of the catheter, a pull wire is arranged in the catheter and passes through the pigtail section, and the filling port of the particle channel is arranged on the rear end face of the catheter. The biliary drainage tube with end face implanted radioactive particles has the advantages that no hole needs to be opened on the side wall of the catheter, the overall structural integrity of the catheter body is completely reserved, the bending resistance and the tensile resistance of the catheter body are obviously improved, and the problems of the catheter body breakage, unsmooth drainage after bending and the like in clinical use are effectively avoided.

Description

Technical Field

[0001] This invention relates to biliary interventional devices, and more particularly to a biliary drainage tube with an end face capable of implanting radioactive particles, suitable for bile drainage in patients with malignant biliary obstruction. 125 I-particle internal radiotherapy is a core clinical application that integrates percutaneous transhepatic biliary drainage (PTCD) with intra-arterial radiotherapy for biliary tumors. Background Technology

[0002] Malignant biliary obstruction is a common clinical complication caused by malignant tumors such as pancreatic cancer, bile duct cancer, and gallbladder cancer compressing or invading the bile duct. It can lead to cholestasis, progressive liver damage, and in severe cases, fatal consequences such as liver and kidney failure and septic shock. Currently, percutaneous transhepatic biliary drainage (PTCD) is the preferred palliative treatment for patients with advanced malignant biliary obstruction who cannot undergo surgical resection. It can effectively relieve biliary obstruction, improve liver function, and prolong patient survival.

[0003] However, simple biliary drainage can only relieve obstruction symptoms and cannot treat the tumor itself. Continued tumor progression can lead to re-blockage of the drainage tube, resulting in a still relatively short patient survival. To address this issue, clinical practice has gradually adopted combined PTCD (percutaneous transluminal biliary drainage) with other methods. 125 A comprehensive treatment plan involving intra-biliary radiotherapy with I-particles, which involves placing a radioactive seed carrier within the bile duct... 125 The I-particle drainage tube, while draining bile, utilizes... 125 The continuous emission of low-energy gamma rays from I particles for local radiotherapy of tumors can effectively inhibit tumor growth, prolong the patency of drainage tubes, and significantly improve patient survival.

[0004] Application No. 202610205044.0 discloses a biliary drainage tube with particle radiotherapy function, including a tube body, a pull wire, and a pull wire traction and fastening device. The tube body has a flexible pig tail section at its front end, and an axially arranged drainage cavity and particle cavity inside. The pig tail section has a drainage hole in its wall connecting to the drainage cavity. The pull wire extends along the drainage cavity to the pig tail section, passes through the pull wire holes at both ends of the pig tail section, and then extends from the rear end of the tube body and converges to the fastening device. The front end of the first connector sleeve of the fastening device is fixed to the rear end of the tube body and communicates with the drainage cavity through the inner tube of the connector. The second connector sleeve is loosely fitted onto the inner tube of the connector. One end of the pull wire is fixed to the first connector sleeve, and the other end movably passes through the second connector sleeve. Pulling the pull wire can bend the pig tail section. Rotating the second connector sleeve to a set angle clamps the pull wire through the angle misalignment, maintaining the pig tail section in a bent state. This invention can conveniently control the bending of the pig tail section and stably maintain its anchored state, effectively improving the safety and reliability of clinical catheter placement.

[0005] This invention has the following drawbacks:

[0006] 1. This invention uses an arc-shaped particle groove on the rear sidewall of the tube to fill the particles, which is a typical sidewall implantation structure for radioactive particles, directly damaging the overall integrity of the tube wall. The tube has weak resistance to bending and tension, and problems such as tube breakage and poor drainage after bending occur in clinical use.

[0007] 2. This invention lacks a dedicated integrated sealing structure at the pull-wire perforation point; the pull-wire fixing structure and bile seal are independent of each other. On the one hand, bile leakage is prone to occur at the pull-wire hole location, increasing the patient's risk of infection; on the other hand, the split structure increases assembly and locking steps, making the overall operation process cumbersome.

[0008] 3. The tube body of this invention only has a dual-lumen structure of main drainage cavity + particle cavity, without an independent flushing channel. Clinical flushing can only be completed through the main drainage cavity, and the flushing process must interrupt normal bile drainage, which can easily lead to bile stasis; at the same time, without a dedicated flushing channel, it is impossible to directionally flush the sludge and necrotic tissue attached to the outer wall of the tube and the bile duct mucosa, and it is impossible to achieve simultaneous flushing and drainage.

[0009] 4. This invention does not integrate supporting consumables. In clinical use, medical staff need to prepare and verify various scattered parts separately, which is time-consuming in preoperative preparation and results in low overall operational efficiency.

[0010] The utility model patent with patent number 202021581869.7 discloses a subcutaneous implantable, portable, and replaceable device. 125 The I-particle bile duct drainage tube, this utility model also has four major drawbacks: side wall openings that damage the tube body, separate sealing and pull wire, outdated flushing function, and scattered consumables.

[0011] Therefore, there is an urgent need to design a biliary drainage tube with high structural strength, good sealing performance, independent flushing function, and convenient operation to solve the above-mentioned defects of existing technology and improve the treatment effect and quality of life of patients with malignant biliary obstruction. Summary of the Invention

[0012] The technical problem to be solved by the present invention is to provide a biliary drainage tube with good resistance to bending and tension, which is not prone to breakage during clinical use and has smooth drainage after bending.

[0013] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is a biliary drainage tube that can implant radioactive particles at its end face, including a catheter and an end connection assembly. The catheter has a main drainage cavity and at least one particle cavity axially arranged inside. The particle cavity is used to load radioactive particles. The front end of the catheter has a flexible pig tail section. A pull wire passing through the pig tail section is inserted inside the catheter. The loading port of the particle cavity is opened at the rear end face of the catheter.

[0014] The biliary drainage tube described above, capable of implanting radioactive particles at its end face, comprises an end-connecting assembly including an inner conical catheter seat and an outer conical fixation seat. The inner conical catheter seat includes a through-hole, and the rear end of the catheter is fixed to the front end of the central hole of the inner conical catheter seat. The outer conical fixation seat has a through-hole along its central axis, and a standard Luer connector is provided at its rear end. The rear part of the central hole of the inner conical catheter seat includes an inner conical hole that is smaller at the front and larger at the rear. The front end of the outer conical fixation seat includes a conical connector adapted to the inner conical hole. The outer conical fixation seat and the inner conical catheter seat are connected by... The connection is made by thread, with the tapered connector fitting snugly against the inner tapered hole. The pull wire has a fixed end and a movable end. The fixed end of the pull wire is fixed to the connection between the inner tapered catheter seat and the rear end of the catheter. The inner tapered catheter seat has a pull wire penetration hole that communicates with the center hole of the inner tapered catheter seat. The movable end of the pull wire extends along the main drainage cavity, passes through the pig tail section, turns back, passes through the contact surface between the tapered connector and the inner tapered hole, and exits through the pull wire penetration hole. The contact surface between the tapered connector and the inner tapered hole achieves the limiting of the pull wire and the sealing and leakage prevention between the inner tapered catheter seat and the outer tapered fixed seat.

[0015] The biliary drainage tube described above, which allows for the implantation of radioactive particles at its end face, includes a C-shaped pull-wire ring at the end. The movable end of the pull wire passes through the pull-wire penetration hole and connects to the pull-wire ring. The outer wall of the inner conical catheter seat is provided with a rectangular external spline or groove, and the inner wall of the pull-wire ring is provided with a convex key that mates with the external spline or groove. The pull-wire ring is fastened to the inner conical catheter seat, and the convex key on the inner wall of the pull-wire ring is engaged in the groove of the rectangular external spline of the inner conical catheter seat or in the groove of the inner conical catheter seat.

[0016] The biliary drainage tube described above, which allows for the implantation of radioactive particles at its end face, comprises two structural forms. The first structural form is a two-lumen structure, including one main drainage lumen and one particle lumen. The second structural form is a three-lumen structure, comprising one main drainage lumen and two symmetrically arranged particle lumens.

[0017] The biliary drainage tube described above, which allows for the implantation of radioactive particles at its end face, has a five-lumen cross-shaped structure, including one main drainage lumen, two particle lumens, and two flushing lumens. All lumens are independent of each other and do not communicate with each other. The two particle lumens are arranged symmetrically, and the two flushing lumens are arranged symmetrically. The front part of the flushing lumens includes a flushing hole, which is opened on the side wall of the tube.

[0018] The above-mentioned biliary drainage tube with radioactive particles implantable at the end face has an independent flushing connector on the inner conical catheter seat. The lower end of the independent flushing connector is connected to the main body of the inner conical catheter seat, and the outer end of the independent flushing connector has an external thread to facilitate connection with the flushing fluid supply equipment. The inner hole of the independent flushing connector is connected to the front part of the inner conical hole of the inner conical catheter seat. A flushing diversion block is embedded in the front part of the inner conical hole of the inner conical catheter seat. The flushing diversion block has 5 independent channels inside, and the 5 channels are respectively connected to the main drainage cavity, the particle cavity and the flushing cavity.

[0019] The above-mentioned biliary drainage tube, which allows for the implantation of radioactive particles at its end face, has a flushing diversion block whose main body is a cone-shaped structure, smaller at the front and larger at the rear. This cone is fitted with the front conical surface of the inner conical catheter seat's inner conical bore. A central hole, penetrating both the front and rear ends, is located along the central axis of the cone to connect the main drainage cavity of the catheter with the central hole of the outer conical fixing seat. The flushing diversion block has an I-shaped structure, including a front baffle, a rear baffle, and vertically arranged partitions. The front and rear baffles are connected by the partitions, and a flushing fluid channel exists between them. The upper part of the flushing fluid channel communicates with the inner hole of an independent flushing connector, allowing the flushing fluid to pass through. The channel is divided into left and right parts by a partition; the flushing diversion block also includes two insert tubes arranged laterally on the front end face of the front baffle. The axis of the insert tubes is parallel to the axis of the cone. The inner hole of the insert tube passes through the front baffle and communicates with the flushing fluid channel. The two insert tubes are respectively inserted into the rear end of the corresponding flushing chamber to realize the connection between the two flushing chambers and the flushing fluid channel; the flushing diversion block also includes two particle channels arranged vertically. The particle channels are parallel to the axis of the cone and pass through the cone from front to back. The two particle channels are coaxial with the two corresponding vertically arranged particle chambers on the catheter.

[0020] The biliary drainage tube described above, which allows for the implantation of radioactive particles at its end face, includes a particle fixing rod and a particle filling line. The particle filling line is used to embed radioactive particles and combine them to form a particle chain. The radioactive particles are loaded into the particle cavity in the form of a particle chain. The particle fixing rod is inserted into the loading end of the particle cavity. When the outer conical fixing seat is tightened, the front end face of the outer conical fixing seat presses against the head of the particle fixing rod to achieve axial positioning of the particle chain. The catheter is made of TPU material and coated with a PVP hydrophilic coating. An air vent is opened at the front end of the particle cavity, and a drainage hole is opened on the tube wall of the pig tail section. A contrast ring is provided on the outer wall of the catheter, and the contrast ring is made of platinum-iridium alloy. The outer wall of the catheter is printed with a particle loading indicator line.

[0021] The biliary drainage tube for implanting radioactive particles described above includes an adapter extension tube, which consists of a soft pagoda inner connector, a first PVC connecting tube, a Y-type connector, a Luer plug, a second PVC connecting tube, a tube body clamp, and a rotatable Luer connector assembly. The main pipe of the Y-type connector is connected to the soft pagoda inner connector via the first PVC connecting tube. The side pipe of the Y-type connector is a flushing interface and is equipped with a Luer plug. The main pipe of the Y-type connector is also connected to the rotatable Luer connector assembly via the second PVC connecting tube. The rotatable Luer connector assembly is sealed and connected to the Luer outer connector at the rear end of the outer conical fixing seat. The tube body clamp is sleeved on the outside of the second PVC connecting tube.

[0022] The biliary drainage tube described above, which allows for the implantation of radioactive particles at its end face, is integrated and packaged to form a biliary drainage tube kit. The biliary drainage tube kit also includes an adapter extension tube, a particle implanter, a particle fixation rod, a particle filling suture, a disposable guide wire, and a disposable anti-backflow drainage bag.

[0023] This invention employs a structure that implants radioactive particles at the end face, eliminating the need for opening holes in the sidewall of the catheter. This preserves the overall structural integrity of the catheter, significantly improving its resistance to bending and tension, and effectively preventing problems such as catheter breakage and poor drainage after bending during clinical use. Attached Figure Description

[0024] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0025] Figure 1 This is a schematic diagram of the structure of the biliary drainage tube with radioactive particles implantable at the end face in Embodiment 1 of the present invention.

[0026] Figure 2 This is a schematic diagram of the cross-section of the biliary drainage tube in Embodiment 1 of the present invention.

[0027] Figure 3 This is a cross-sectional view of the posterior structure of the biliary drainage tube in Embodiment 1 of the present invention.

[0028] Figure 4 This is an anatomical view of the end connection assembly in Embodiment 1 of the present invention.

[0029] Figure 5 This is a schematic diagram of the cross-section of the biliary drainage tube in Embodiment 2 of the present invention.

[0030] Figure 6 This is a schematic diagram of the cross-section of the biliary drainage tube in Embodiment 3 of the present invention.

[0031] Figure 7 This is a cross-sectional view of the posterior structure of the biliary drainage tube in Embodiment 3 of the present invention.

[0032] Figure 8This is an exploded view of the posterior structure of the biliary drainage tube in Embodiment 3 of the present invention.

[0033] Figure 9 This is a perspective view of the flushing diversion block in Embodiment 3 of the present invention.

[0034] Figure 10 This is a perspective view of the flushing diversion block from another angle in Embodiment 3 of the present invention.

[0035] Figure 11 This is a three-dimensional sectional view of the flushing diversion block installed in the inner conical guide seat according to Embodiment 3 of the present invention.

[0036] Figure 12 This is a schematic diagram of the structure of the adapter extension tube according to an embodiment of the present invention.

[0037] Figure 13 This is a schematic diagram of the end-face implantation of radioactive particles according to an embodiment of the present invention.

[0038] Figure 14 This is a schematic diagram of a biliary drainage tube kit for implanting radioactive particles at the end face, according to an embodiment of the present invention.

[0039] Figure label: 1. Pull the string; 2. 125 1. Particle; 100. Biliary drainage tube; 200. Adapter extension tube; 300. Particle inserter; 400. Guide wire; 500. Particle fixation rod; 600. Particle filling suture; 700. Disposable anti-backflow drainage bag; 10. Biliary drainage tube body; 11. Catheter; 11A. Pig tail segment; 111. Main drainage channel; 112. Particle channel; 113. Pull wire hole; 114. Drainage hole; 115. Particle cavity vent hole; 116. Flushing channel; 12. Imaging ring; 13. Marking line; 20. End connection assembly; 21. Inner conical catheter seat; 211. Center hole; 212. Pull wire penetration hole; 213. Rectangular external spline; 214. Inner conical hole; 215. External thread; 216. Independent flushing connector; 2161. Independent flushing connector external thread; 2162. Independent flushing connector inner hole; 217. Groove; 22. External conical... 221 External conical connector; 222 Nut; 223 Standard Luer external connector; 224 Center hole; 23 Pull ring; 231 Pull ring key; 24 Flushing diverter block; 241 Cone; 242 Front baffle; 243 Rear baffle; 244 Inner hole of insertion tube; 245 Partition; 246 Flushing fluid channel; 247 Insertion tube; 248 Particle channel; 249 Center hole; 201 Soft pagoda internal connector; 202 First PVC connecting pipe; 203 Y-type connector; 203AY-type connector main pipe; 203BY-type connector side pipe (drainage chamber flushing interface); 204 Luer plug; 205 Second PVC connecting pipe; 206 Tube clip (tube clamp); 207 Rotatable Luer connector assembly; 2071 Rotatable Luer nut; 2072 Luer internal connector. Detailed Implementation

[0040] An embodiment of the present invention is a biliary drainage tube kit with an end face capable of implanting radioactive particles, such as... Figure 14 As shown, the entire system adopts an integrated design for drainage and internal radiotherapy, mainly composed of a biliary drainage tube 100, an extension tube 200, a particle implanter 300, a guide wire 400, a particle fixation rod 500, a particle filling suture 600, and a disposable anti-backflow drainage bag 700. Among them, the biliary drainage tube 100 is the core component, including the biliary drainage tube body 10 and the end connection assembly 20.

[0041] The following are embodiments of three biliary drainage tube 100 structures. All three biliary drainage tubes 100 employ the method of implanting radioactive particles at the end face, and their specific structures are as follows:

[0042] 1. Example 1: Implantation of a radioactive particle biliary drainage tube (basic type, 10Fr specification) at the end face of a single-particle cavity, including a biliary drainage tube body 10 and an end connection assembly 20, such as... Figure 1 As shown.

[0043] like Figure 1 As shown, the main body 10 of the biliary drainage tube 100 in this embodiment includes a catheter 11, a contrast ring 12, and a marking line 13.

[0044] like Figure 1 and Figure 2 As shown, catheter 11 has a two-lumen structure, comprising a main drainage channel 111 and an independent particle channel 112. The particle channel 112 is adapted to a 0.8mm outer diameter. 125 The I-particle type is suitable for patients with narrow bile ducts. Catheter 11 is made of TPU (thermoplastic polyurethane elastomer) with a PVP (polyvinylpyrrolidone) hydrophilic coating, providing excellent resistance to bile corrosion, biostability, bending resistance, and tensile strength, while significantly reducing frictional resistance and minimizing damage to the bile duct mucosa. The outer diameter of the catheter is 10 Fr, and the effective length is 45 cm.

[0045] In this embodiment of the biliary drainage tube, the side of the catheter 11 has no particle loading port, while the particle loading port of the cavity 112 is located on the rear end face of the catheter 11. Figure 1 As shown, the front end of the particle cavity 112 has a particle cavity exhaust port 115 that communicates with the outside, eliminating the air gap at the front end of the particle cavity 112, facilitating particle placement, and eliminating the interference of the air gap at the front of the particle cavity 112 on the radiotherapy effect.

[0046] The imaging ring 12 is made of platinum-iridium alloy and is fixed on the outer wall of the catheter 11. It is embedded at the rear end of a drainage hole 114 on the last side of the catheter 11 (near the end connection component 20). It can be clearly visualized under X-ray or B-ultrasound guidance, which makes it easy for doctors to accurately locate the position of the drainage hole 114 on the catheter 11.

[0047] The anterior portion of the catheter 11 includes a flexible pig tail segment 11A, the external shape of which is basically consistent with the shape of existing biliary drainage tubes. The flexible pig tail segment 11A at the anterior end of the catheter 11 acts as an anchor to prevent displacement within the biliary lumen. A pull wire 1 is arranged in the axially arranged main drainage channel 111 within the catheter 11; the pull wire 1 controls the bending and straightening state of the pig tail segment 11A. Figure 1 As shown, pull-wire holes 113 are opened on the tube walls at both ends of the pig tail section 11A. The main body of the pull-wire 1 extends from the rear of the conduit 11 along the main drainage channel 111 to the pig tail section 11A. It first passes out through one of the pull-wire holes 113, and then passes back through the other pull-wire hole 113 to the main drainage channel 111. Through this through-and-back arrangement, the pull-wire 1 and the pig tail section 11A form a linkage force relationship, which can drive the pig tail section 11A to bend. The two ends of the pull-wire 1 that are folded back from the pig tail section 11A are respectively fixed to the end connecting assembly 20. When the end of the pull-wire 1 is tightened, the conduit 11 in the pig tail section 11A is bent back under the tension of the pull-wire 1. When the pull-wire 1 is relaxed, the conduit 11 in the pig tail section 11A can be straightened when the top core (an external tool for temporary auxiliary tube placement, not shown in the figure) is inserted into the conduit 11. Furthermore, multiple drainage holes 114 are evenly provided on both sides of the inner and outer rings of the tube 11 tail section 11A of the catheter 11 to connect the main drainage cavity 111 with the outside, for the purpose of draining bile in the bile duct.

[0048] like Figure 1 As shown, the end connection assembly 20 includes an inner conical guide seat 21, an outer conical fixing seat 22, and a pull wire ring 23.

[0049] like Figure 3 and Figure 4 As shown, the inner conical catheter seat 21 is made of ABS material. The rear end of the catheter 11 is inserted into the front end of the central hole 211 of the inner conical catheter seat 21, and the two are fixed together with medical adhesive. A wire penetration hole 212 on the outer wall of the rear part of the inner conical catheter seat 21 communicates with the axial central hole 211 of the inner conical catheter seat 21. A rectangular external spline 213 is located on the outer wall of the middle part of the inner conical catheter seat 21 for fixing the wire loop 23. At the rear of the axial central hole 211 of the inner conical catheter seat 21, there is an inner conical hole 214, which is smaller at the front and larger at the back, matching the conical connector 221 of the outer conical fixation seat 22. The rear end of the inner conical catheter seat 21 has an external thread 215 for connecting to the outer conical fixation seat 22.

[0050] The outer conical fixing seat 22 is made of ABS material. Its front end includes an outer conical connector 221, which is smaller at the front and larger at the back. The taper of the connector 221 matches the taper of the inner conical conical hole 214 of the inner conical conical guide seat 21. The conical connector 221 of the outer conical fixing seat 22 and the inner conical hole 214 of the inner conical conical guide seat 21 achieve simultaneous wire fixation and bile sealing, effectively preventing bile leakage from the wire hole.

[0051] The outer conical fixing seat 22 has a nut 222 on its outer periphery at the middle. The internal thread of the nut 222 is threadedly connected to the external thread 215 of the inner conical guide seat 21. The outer conical fixing seat 22 has a standard Luer connector 223 at its rear end, which can be connected to an adapter extension tube 200 or a syringe. The outer conical fixing seat 22 has a central hole 224 that is open at both ends along its central axis.

[0052] The pull cord 1 is made of medical-grade high-strength nylon thread. One end is bonded to the connection between the rear end of the catheter 11 and the inner conical catheter seat 21. The other end passes through the two pull cord holes 113 of the pigtail section 11A at the front of the catheter 11 along the main drainage channel 111 of the catheter 11 and returns, exiting through the central hole 211 and the pull cord penetration hole 212 of the inner conical catheter seat 21, and is tied to the pull cord ring 23. The pull cord ring 23 is a C-shaped ring larger than a semicircle, made of ABS material. The inner wall of the pull cord ring 23 has a protruding key (not shown in the figure) that matches the groove of the rectangular external spline 213 of the inner conical catheter seat 21. The pull cord ring 23 is fastened to the rectangular external spline 213 of the inner conical catheter seat 21. The protruding key on the inner wall of the pull cord ring 23 can be engaged with any groove of the rectangular external spline 213 of the inner conical catheter seat 21, preventing the pull cord ring 23 from rotating circumferentially, protecting the pull cord 1 and facilitating the doctor's operation.

[0053] 2. Example 2: Implantation of a radioactive particle biliary drainage tube (basic type, 12Fr / 13Fr specification) at the 112 end face of a dual-particle cavity.

[0054] This embodiment features a three-lumen structure. The catheter 11 includes one main drainage channel 111 and two symmetrically distributed independent particle channels 112, wherein the 12Fr specification is adapted to an outer diameter of 0.6mm. 125 I-particles, 13Fr specification compatible with outer diameter 0.8mm 125 I-particles are suitable for patients with larger bile duct diameters and larger tumor areas, enabling higher doses of local internal radiotherapy.

[0055] The cross-sectional structure of the conduit 11 is as follows: Figure 5 As shown, the main drainage channel 111 is located at the center of the tube body, and two particle channels 112 are symmetrically distributed on both sides of the main drainage channel 111. The three channels are independent of each other and do not communicate with each other. The outer diameters of the tube bodies are 12Fr and 13Fr, and the effective length of the tube body is 45cm for both.

[0056] The remaining structures (radiation ring 12, inner conical catheter seat 21, outer conical fixing seat 22, fixing pull wire, pull wire ring 23) are completely consistent with those in Example 1.

[0057] 3. Example 3: Five-lumen cross-shaped irrigation type end-face implantation radioactive particle biliary drainage tube (preferred type, 12Fr / 13Fr specification)

[0058] This embodiment is an optimized and upgraded version of embodiment 2. Based on the three-lumen structure of the catheter 11 with dual particle cavities 112 and main drainage cavity 111, two independent flushing cavities 116 are added to form a five-lumen cross-shaped symmetrical distribution structure. It is equipped with a dedicated flushing diversion block 24 to achieve completely independent flushing function. Flushing and drainage do not interfere with each other and can be flushed and drained at the same time.

[0059] Example 3: The cross-sectional structure of the catheter 11 is as follows Figure 6 As shown, a centrally symmetrical, five-chamber cross-shaped design is adopted. The largest central chamber is the main drainage channel 111, responsible for the continuous drainage of bile. The two larger, symmetrical chambers above and below are particle channels 112, used for loading... 125 I-particle internal radiotherapy is performed. The two symmetrical minimum cavities on the left and right are independent irrigation channels 116. The catheter 11 is located at the front of the irrigation channel 116. An irrigation hole (not shown in the figure) is opened on the side wall of the catheter 11. The irrigation fluid can be directly applied to the bile duct mucosa and the outer wall of the drainage tube through the irrigation hole to flush out biliary sludge and necrotic tissue.

[0060] like Figure 7 and Figure 8 As shown, the inner conical conduit seat 21 of Embodiment 3 of the present invention adds a vertically arranged independent flushing connector 216 to the inner conical conduit seat 21 of Embodiment 1. The lower end of the independent flushing connector 216 is connected to the main body of the inner conical conduit seat 21. The outer end of the independent flushing connector 216 has an external thread 2161, which facilitates connection with the flushing fluid supply device. The inner hole 2162 of the independent flushing connector 216 communicates with the front part of the inner conical hole 214 of the inner conical conduit seat 21.

[0061] The front (small end) of the inner tapered bore 214 of the inner conical guide seat 21 is fitted with a flushing diverter block 24. The structure of the flushing diverter block 24 is as follows: Figure 9 and Figure 10As shown, the flushing diversion block 24 is made of medical-grade transparent ABS material. Its main body is a cone 241, smaller at the front and larger at the back. A central hole 249 runs through the front and rear ends of the cone 241 along its central axis. This central hole 249 connects the main drainage channel 111 of the catheter 11 to the central hole 224 of the outer conical fixing seat 22. The flushing diversion block 24 is installed at the small end of the inner conical hole 214 of the inner conical catheter seat 21, with the cone 241 fitting the conical surface of the inner conical hole 214. The flushing diversion block 24 is I-shaped and includes a front baffle 242, a rear baffle 243, and a vertically arranged partition 245. The front baffle 242 and the rear baffle 243 are connected by the partition 245.

[0062] A flushing fluid channel 246 is located between the front baffle 242 and the rear baffle 243. The upper part of the flushing fluid channel 246 communicates with the inner hole 2162 of the independent flushing connector 216. The flushing fluid channel 246 is divided into left and right parts by a partition 245. The flushing diversion block 24 also includes two insertion tubes 247, which are arranged laterally on the front end face of the front baffle 242. The axis of the insertion tubes 247 is parallel to the axis of the cone 241. The inner hole 244 of the insertion tubes 247 passes through the front baffle 242 rearward and communicates with the flushing fluid channel 246. The two insertion tubes 247 are respectively inserted into the rear end of the corresponding flushing chamber 116, realizing the communication between the two flushing chambers 116 and the flushing fluid channel 246. The flushing diversion block 24 also includes two particle channels 248 arranged vertically. The particle channels 248 are parallel to the axis of the cone 241 and pass through the cone 241 from front to back. The two vertically arranged particle channels 248 are coaxial with the two vertically arranged particle cavities 112 on the conduit 11, respectively.

[0063] The front end of the flushing diversion block 24 is sealed to the two flushing chambers of the conduit 11, and is integrally embedded inside the inner conical conduit seat 21. The conical surface of the flushing diversion block 24 matches the inner conical hole 214 of the inner conical conduit seat 21. The flushing diversion block 24 is provided with an independent flushing fluid channel 246, which completely isolates the main drainage channel 111, the two particle channels 112 and the two flushing channels 116, ensuring that the flushing fluid does not enter the main drainage channel 111 and the particle channels 112.

[0064] The catheter 11 features a structure with two flushing cavities 116, which significantly improves flushing efficiency. The flushing fluid flows out from the side hole at the front end of the catheter, directly flushing the tumor surface and the outer wall of the drainage tube. Flushing and drainage do not interfere with each other, allowing flushing and drainage to occur simultaneously. This effectively prevents sludge adhesion and drainage tube blockage, and prolongs the patency of the drainage tube.

[0065] Based on the structure of Embodiment 1, the inner conical conduit seat 21 of Embodiment 3 of the present invention adds a vertically arranged independent flushing connector 216, and at the same time cancels the rectangular external spline 213, and instead sets a slot 217 at the front to cooperate with the protruding key 231 on the inner wall of the pull ring 23 for anti-rotation positioning of the pull ring 23 and prevents the pull ring 23 from rotating circumferentially.

[0066] The remaining structures of Embodiment 3 of the present invention (radiation ring 12, inner conical catheter seat 21, outer conical fixing seat 22, pull wire 1 and pull wire ring 23) are the same as those of Embodiment 2.

[0067] Particle placement and fixation system

[0068] All three embodiments of the biliary drainage tube employ a structure with radioactive particles implanted at the end face. After removing the outer conical fixation base 22, the openings of the corresponding number of particle cavities 112 are directly visible. Figure 13 As shown, according to the marking line 13 on the outside of the tube, a suitable length of particle filling line 600 is cut. The filling line and particle inserter 300 in the kit can then be used to insert the particle filling line and particle inserter 600 into the tube. 125 I particles are sequentially placed into each particle cavity 112 and pushed by the particle fixation rod 500, allowing multiple particles to form a particle chain and cross the tumor area. After removing the particle inserter 300, the particle fixation rod 500 is inserted again. After tightening the outer conical fixation seat 22, the front end of the outer conical fixation seat 22 simultaneously presses against the particle fixation rod 500, fixing the particles in all particle cavities 112 and effectively preventing particle displacement. The particle fixation rod 500 is of standard length, and the outer side of the catheter 11 is printed with marking lines 13 to facilitate the doctor's measurement of the cut length of the particle filling line 600 from the outside, accurately determining the particle filling position.

[0069] Adapter extension tube 200

[0070] like Figure 12As shown, the adapter extension tube 200 consists of a flexible pagoda-shaped inner connector 201, a first PVC connecting pipe 202, a Y-type connector 203, a Luer plug 204, a second PVC connecting pipe 205, a pipe body clamp 206, and a rotatable Luer connector assembly 207. The rotatable Luer connector assembly 207 consists of a rotatable Luer nut 2071 and a Luer inner connector 2072. The rear end of the main pipe 203A of the Y-type connector 203 is connected to the flexible pagoda-shaped inner connector 201 through the first PVC connecting pipe 202, and the flexible pagoda-shaped inner connector 201 is connected to the pagoda connector of the drainage bag 700. The front end of the main pipe 203A of the Y-type connector 203 is connected to the rotatable Luer connector assembly 207 through the second PVC connecting pipe 205, and the rotatable Luer connector assembly 207 is connected to the standard Luer outer connector 223 of the outer conical fixing seat 22 of the biliary drainage tube 100. The tube clamp 206 is fitted over the second PVC connecting tube 205. The side tube 203B of the Y-type connector 203 is the drainage cavity flushing interface, used for flushing the inside of the main drainage cavity. When not in use, the drainage cavity flushing interface is sealed with a Luer plug 204. The rotatable Luer nut 2071 and the inner Luer connector 2072 of the rotatable Luer connector assembly 207 are separate structures, making operation more convenient. The tube clamp 206 controls the fluid flow, and the external fixation occupies little space, avoiding the discomfort of compression when the patient is lying on their side.

[0071] Other supporting components

[0072] The biliary drainage tube kit that allows for the implantation of radioactive particles also includes a particle implanter 300, a disposable guidewire 400, a particle filling suture 600, a particle fixation rod 500, and a disposable anti-backflow drainage bag 700. All components are pre-integrated into one package, eliminating the need for medical staff to prepare and verify consumables separately.

[0073] Operation process example

[0074] Example 1: Procedure for implanting a radioactive particle biliary drainage tube at the end face of a single-particle cavity 112

[0075] The specific operating procedure of this device is adapted to percutaneous transhepatic biliary drainage (PTCD) combined with... 125 The specific implementation steps for intra-particle radiotherapy in clinical practice are as follows:

[0076] 1. Preoperative preparation: Select a 10Fr-1 drainage tube according to the patient's bile duct diameter and tumor condition, and check that all components in the kit are intact. Prepare the puncture needle and 0.8mm outer diameter particles.

[0077] 2. Percutaneous hepatic cholangiography: Under X-ray or ultrasound guidance, a needle is percutaneously inserted into the bile duct, and contrast agent is injected to reconfirm the location of biliary obstruction and the extent of the tumor. The required contrast agent is calculated based on the tumor length. 125The number of I particles 2.

[0078] 3. Particle Loading: Based on the tumor length and location, and the marking line 13 on the outer side of the tube, cut a suitable length of filling wire. Unscrew the outer conical fixation seat 22, and use the particle inserter 300 to insert into the single-particle cavity 112 opening on the end face. Load the pre-prepared filling wire and... 125 I particles 2 are sequentially placed into particle channels 112. The particles are pushed using particle fixation rods 500, ensuring that the particle chain spans 2 cm across both ends of the tumor area. Then, the particle inserter 300 is removed, and the particle fixation rods 500 are inserted. The outer conical fixation seat 22 is pre-tightened to press the particle fixation rods 500 against its end face, preventing particle displacement.

[0079] 4. Guidewire insertion and drainage tube advancement: Insert the guidewire 400 through the puncture needle, withdraw the puncture needle, insert the dilator along the guidewire 400 to expand the puncture channel, and then insert the pre-loaded... 125 The biliary drainage tube of particle I2 is pushed along guide wire 400 to the target position, so that the tip of the drainage tube passes over the obstruction site and enters the duodenum, and then withdraws from guide wire 400.

[0080] 5. Drainage Tube Fixation and Sealing: Tighten the pull line 1 to bend the pigtail section 11A of the biliary drainage tube head, fixing the drainage tube and preventing displacement. Tighten the outer conical fixing seat 22 to press the particle fixing rod 500 against its end face, preventing particle displacement. At the same time, the outer conical fixing seat 22 fits against the conical surface of the inner conical catheter seat 21, fixing the pull line 1 and achieving bile sealing. Wrap the pull line around the inner conical catheter seat 21, and then fasten the pull line loop 23 onto the inner conical catheter seat 21 and lock it in place.

[0081] 6. Drainage System Connection: Connect the Luer inner connector 2072 of the adapter extension tube 200 to the standard Luer outer connector 223 of the biliary drainage tube, and tighten the rotatable Luer nut 2071. Insert the pagoda connector of the disposable anti-backflow drainage bag 700 into the soft pagoda inner connector 201 of the adapter extension tube 200, open the tube clamp 206, and confirm that bile drainage is unobstructed.

[0082] 7. Postoperative fixation and care: Secure the drainage tube to the patient's body surface using a surface catheter fixation device and a medical catheter fixation device to prevent dislodgement. Postoperatively, regularly flush the main drainage cavity through the side tube 203B of the Y-type connector 203 of the adapter extension tube 200 to maintain unobstructed drainage. Regularly follow up with X-rays to confirm that the particle position has not shifted.

[0083] Example 2: Procedure for implanting a radioactive particle biliary drainage tube at the 112-end face of a dual-particle cavity

[0084] Steps 1, 2, and 4 are the same as in Example 1, while steps 3 and 5 are optimized as follows:

[0085] 3. Particle Loading: Based on the tumor length and location, and the marking line 13 on the outer side of the catheter 11, cut a suitable length of particle-filling wire 600. Unscrew the outer conical fixation base 22. Using the particle inserter 300 included in the kit, insert it sequentially into the openings of the two particle cavities 112 on the end face. Insert the pre-prepared particle-filling wire 600 and the particle inserter 300 into the two cavities through the inner cavity of the particle inserter 300. 125 1. Particle 2. Using particle fixation rods 500, push the particles into the two cavities respectively, so that the length of the particle chains on both sides spans 2cm across both ends of the tumor area. Then remove the particle inserter 300 and insert the particle fixation rods 500 respectively. Pre-tighten the outer conical fixation seat 22 to press the two particle fixation rods 500 through its end face to prevent particle displacement.

[0086] 5. Fixing and sealing the drainage tube: Tighten the pull wire 1 to bend the pig tail section 11A of the biliary drainage tube head, fixing the drainage tube and preventing displacement. Tighten the outer conical fixing seat 22, simultaneously pressing the particle fixing rods 500 of the two particle cavities 112 through its end face to prevent particle displacement. The remaining operations are the same as those in Example 1.

[0087] The operation in steps 6-7 is exactly the same as in Example 1.

[0088] Example 3: Operation procedure of a five-lumen cross-shaped independently flushing biliary drainage tube

[0089] Steps 1, 2, 4, 5, and 6 are completely identical to those in Example 2. Steps 3 and 7 are optimized as follows:

[0090] 3. Particle Loading: Based on the tumor length and location, and the marking line 13 on the outer side of the tube, cut a suitable length of particle-filling wire 600. Unscrew the outer conical fixation seat 22. Using the particle inserter 300 included in the kit, insert it sequentially into the upper and lower particle channels 248 of the flushing diversion block 24. Insert the pre-prepared particle-filling wire 600 and the particle inserter 300 into the two channels through the inner cavity of the particle inserter 300 respectively. 125 1. Particle 2. Using particle fixation rods 500, push the particles into the two cavities respectively, so that the length of the particle chains on both sides spans 2cm across both ends of the tumor area. Then remove the particle inserter 300 and insert the particle fixation rods 500 respectively. Pre-tighten the outer conical fixation seat 22 to press the two particle fixation rods 500 through its end face to prevent particle displacement.

[0091] 7. Postoperative Fixation and Care: Securely fix the drainage tube to the patient's body surface using a surface catheter fixation device and a medical catheter fixation device. Postoperatively, perform bile duct irrigation daily through the independent irrigation connector 216 on the inner conical catheter seat 21, slowly injecting 20-30 ml of normal saline each time. Irrigation and drainage can be performed simultaneously without interrupting bile drainage. Every 3 days, irrigate the main drainage cavity once through the side tube 203B of the Y-type connector 203 of the adapter extension tube 200. Regularly follow up with X-rays to confirm that the particle position has not shifted.

[0092] Beneficial effects:

[0093] 1. This invention uses a structure with radioactive particles implanted at the end face, which eliminates the need for opening holes in the side wall of the catheter, thus preserving the overall structural integrity of the tube. This significantly improves the tube's resistance to bending and tension, effectively avoiding problems such as tube breakage and poor drainage after bending during clinical use.

[0094] 2. Two basic specifications are available: single-particle channel (two-lumen) and dual-particle channel (three-lumen), which can be flexibly selected according to the patient's bile duct diameter and tumor condition to meet different clinical needs. The dual-particle channel can achieve higher doses of local internal radiotherapy, improving the treatment effect of tumors.

[0095] 3. An innovative design incorporates an outer conical fixation base and an inner conical catheter base structure. By fitting the conical surfaces together, it simultaneously achieves the dual functions of wire fixation and bile sealing. This one-step solution addresses the technical challenges of unreliable wire fixation and easy bile leakage from the wire hole in traditional products. The operation is simple and reliable, reducing the risk of infection for patients.

[0096] 4. The end-face compression particle fixation method is adopted. Tightening the outer conical fixation seat can simultaneously compress the particle fixation rods of all particle cavities through its end face, effectively preventing postoperative particle displacement, ensuring the stability of radiotherapy effect, and avoiding unnecessary radiation damage to normal tissues.

[0097] 5. The particle fixation rod is of standard length, and the outer side of the tube is printed with marking line 13, which makes it convenient for doctors to accurately measure and determine the particle filling position, improving the accuracy of particle placement and operational efficiency.

[0098] 6. The drainage catheter adopts a TPU+PVP hydrophilic coating structure, which has excellent resistance to bile corrosion, biological stability and lubricity, reduces damage to the bile duct mucosa, lowers the incidence of complications and extends the product's service life.

[0099] 7. The kit integrates all necessary components such as biliary drainage tube, adapter extension tube, anti-backflow drainage bag, guide wire, particle implanter, particle filling line, and particle fixation rod, eliminating the need for medical staff to prepare and check consumables separately, greatly shortening preoperative preparation time and improving clinical operation efficiency.

[0100] 8. The preferred embodiment features a newly added five-chamber, cross-shaped, independent irrigation system, achieving completely independent irrigation of the biliary tract wall. Irrigation and drainage do not interfere with each other, allowing for simultaneous irrigation and drainage, thus avoiding bile stasis during irrigation. The irrigation fluid does not enter the particle chamber, preventing particle displacement due to impact and ensuring the stability of the radiotherapy effect.

[0101] 9. The flushing fluid in the independent flushing chamber acts directly on the bile duct mucosa and the outer wall of the drainage tube, effectively flushing away biliary sludge and necrotic tumor tissue, significantly reducing the risk of drainage tube blockage and prolonging the drainage tube patency time. The dual flushing chamber design can greatly improve flushing efficiency.

[0102] 10. The overall design is fully compatible with the existing clinical operation procedures of PTCD combined with internal radiotherapy. Medical staff can quickly get started without additional training, and the difficulty of clinical promotion and translation is low.

Claims

1. A biliary drainage tube capable of implanting radioactive particles at its end face, comprising a catheter and an end connection assembly, wherein the catheter has an axially arranged main drainage cavity and at least one particle cavity inside, the particle cavity being used to load radioactive particles, the catheter tip having a flexible pig tail segment, and a drawstring passing through the pig tail segment passing through the catheter, characterized in that, The filling port of the particle cavity is located on the rear end face of the catheter.

2. The biliary drainage tube with end-face implantation of radioactive particles according to claim 1, characterized in that, The end connection assembly includes an inner conical guide seat and an outer conical fixing seat. The inner conical guide seat includes a through central hole, and the rear end of the guide tube is fixed to the front end of the central hole of the inner conical guide seat. The outer conical fixing seat has a through central hole along the central axis, and a standard Luer connector is provided at the rear end of the outer conical fixing seat. The rear part of the central hole of the inner conical guide seat includes an inner conical hole that is smaller at the front and larger at the rear. The front end of the outer conical fixing seat includes a conical connector that fits the inner conical hole. The outer conical fixing seat and the inner conical guide seat are connected by a thread. The conical connector fits snugly against the inner conical hole; the pull wire has a fixed end and a movable end, the fixed end of the pull wire is fixed to the connection between the inner conical catheter seat and the rear end of the catheter; the inner conical catheter seat has a pull wire penetration hole that communicates with the central hole of the inner conical catheter seat, the movable end of the pull wire extends along the main drainage cavity, passes through the pig tail section and then turns back, passes through the contact surface between the conical connector and the inner conical hole, and exits from the pull wire penetration hole; the contact surface between the conical connector and the inner conical hole achieves the limiting of the pull wire and the sealing and leakage prevention between the inner conical catheter seat and the outer conical fixed seat.

3. The biliary drainage tube with end-face implantation of radioactive particles according to claim 2, characterized in that, The end connection assembly includes a C-shaped pull ring, with the movable end of the pull wire passing through the pull wire penetration hole and connecting to the pull ring; the outer wall of the inner conical guide seat is provided with a rectangular external spline or slot, and the inner wall of the pull ring is provided with a protruding key that mates with the external spline or slot; the pull ring is fastened to the inner conical guide seat, and the protruding key on the inner wall of the pull ring is engaged in the groove of the rectangular external spline of the inner conical guide seat or in the slot of the inner conical guide seat.

4. The biliary drainage tube with end-face implantation of radioactive particles according to claim 1, characterized in that, The catheter has two structural forms. The first structural form is a two-lumen structure, which includes a main drainage cavity and a particle cavity. The second structural form is a three-lumen structure, which includes a main drainage cavity and two symmetrically arranged particle cavities.

5. The biliary drainage tube with end-face implantation of radioactive particles according to claim 2, characterized in that, The catheter has a five-lumen cross-shaped structure, including one main drainage cavity, two particle cavities, and two flushing cavities. All cavities are independent of each other and do not communicate with each other. The two particle cavities are arranged symmetrically, and the two flushing cavities are arranged symmetrically. The front part of the flushing cavity includes a flushing hole, which is opened on the side wall of the catheter.

6. The biliary drainage tube with an end face capable of implanting radioactive particles according to claim 5, characterized in that, The inner conical conduit seat is equipped with an independent flushing connector. The lower end of the independent flushing connector is connected to the main body of the inner conical conduit seat. The outer end of the independent flushing connector is provided with an external thread to facilitate connection with the flushing fluid supply equipment. The inner hole of the independent flushing connector is connected to the front part of the inner conical hole of the inner conical conduit seat. A flushing diversion block is embedded in the front part of the inner conical hole of the inner conical conduit seat. The flushing diversion block has 5 independent channels inside, and the 5 channels are respectively connected to the main drainage cavity, the particle cavity and the flushing cavity.

7. The biliary drainage tube with an end face capable of implanting radioactive particles according to claim 5, characterized in that, The main body of the flushing diversion block is a cone-shaped structure, smaller at the front and larger at the rear. The cone is fitted to the front conical surface of the inner conical bore of the inner conical catheter seat. A central hole, penetrating the front and rear ends, is located on the central axis of the cone to connect the main drainage channel of the catheter with the central hole of the outer conical fixing seat. The flushing diversion block has an I-shaped structure, including a front baffle, a rear baffle, and vertically arranged partitions. The front and rear baffles are connected by the partitions, and a flushing fluid channel exists between them. The upper part of the flushing fluid channel communicates with the inner hole of an independent flushing connector. The flushing fluid channel is divided into left and right sections by the partitions. The flushing diversion block consists of two parts; it also includes two insert tubes arranged laterally on the front end face of the front baffle, with the insert tube axis parallel to the cone axis. The inner hole of the insert tube passes through the front baffle and communicates with the flushing fluid channel. The two insert tubes are respectively inserted into the rear end of the corresponding flushing chamber to realize the connection between the two flushing chambers and the flushing fluid channel; the flushing diversion block also includes two particle channels arranged vertically, with the particle channels parallel to the cone axis and passing through the cone from front to back. The two particle channels are coaxial with the two corresponding vertically arranged particle chambers on the catheter.

8. The biliary drainage tube with end-face implantation of radioactive particles according to claim 2, characterized in that, The device includes a particle fixing rod and a particle filling line. The particle filling line is used to embed radioactive particles and combine them to form a particle chain. The radioactive particles are loaded into the particle channel in the form of a particle chain. The particle fixing rod is inserted into the filling end of the particle channel. When the outer conical fixing seat is tightened, the front end face of the outer conical fixing seat presses against the head of the particle fixing rod to achieve axial positioning of the particle chain. The catheter is made of TPU material and coated with a PVP hydrophilic coating. An exhaust hole is opened at the front end of the particle channel, and a drainage hole is opened on the tube wall of the pig tail section. A radiopaque ring is provided on the outer wall of the catheter. The radiopaque ring is made of platinum-iridium alloy. The outer wall of the catheter is printed with particle loading marking lines.

9. The biliary drainage tube with end-face implantation of radioactive particles according to claim 2, characterized in that, The system includes an adapter extension tube, which consists of a soft pagoda inner connector, a first PVC connecting pipe, a Y-type connector, a Luer plug, a second PVC connecting pipe, a pipe body clamp, and a rotatable Luer connector assembly. The main pipe of the Y-type connector is connected to the soft pagoda inner connector via the first PVC connecting pipe. The side pipe of the Y-type connector is a flushing interface and is equipped with a Luer plug. The main pipe of the Y-type connector is also connected to the rotatable Luer connector assembly via the second PVC connecting pipe. The rotatable Luer connector assembly is sealed and connected to the Luer outer connector at the rear end of the outer conical fixing seat. The pipe body clamp is sleeved on the outside of the second PVC connecting pipe.

10. The biliary drainage tube capable of implanting radioactive particles at its end face according to claim 1, characterized in that, The biliary drainage tube is integrated and packaged to form a biliary drainage tube kit, which also includes an adapter extension tube, a particle inserter, a particle fixing rod, a particle filling wire, a disposable guide wire, and a disposable anti-backflow drainage bag.

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