Biliary-pancreatic duct stent for targeted drug delivery and method of use

Abstract

The application relates to the technical field of medical devices, and particularly provides a drug-targeting delivery biliary-pancreatic duct stent and a use method. The stent body is internally hollow and provided with an anti-retreating valve at the front end, and the stent body is moved to a blocked position to dredge the blocked position. The rear end of the stent body is provided with an anti-backflow valve, the anti-backflow valve prevents the backflow of bile or pancreatic juice, and a drug storage assembly is arranged in the stent body. The drug storage assembly internally stores drugs for decomposing blockages. When the stent body is blocked by gallstones, mucus or the like, the internal pressure of the stent body is increased to make the drug storage assembly release the drugs. The drugs can directly act on the blocked position, the blockages can be automatically decomposed without additional intervention, the trouble of replacing the traditional stent after blockage by surgery is avoided, and the pain of the patient and the medical cost are reduced.

Description

Technical Field

[0001] This invention relates to the field of medical device technology, and in particular to a drug-targeted delivery bile and pancreatic duct stent and its method of use. Background Technology

[0002] Biliary and pancreatic duct stents are interventional medical devices used to support the bile and pancreatic ducts and restore bile or pancreatic juice drainage. Their core function is to relieve obstruction and prevent complications.

[0003] For example, Chinese patent CN120436840B discloses a plastic biliary stent. This solution includes a stent body, a delivery unit, and a guidewire. The stent body includes a main tube, a first wing, and a second wing. The first wing is located at the distal end of the main tube, and the second wing is located at the proximal end of the main tube. The ends of the first and second wing that are close to each other can unfold relative to the main tube. The delivery unit includes a sheath and an inner tube. The inner tube moves within the sheath, and the distal end of the inner tube includes a cutting head. The guidewire is sequentially threaded through the main tube and the inner tube. The first wing is housed in the main tube via a connecting line. The distal end of the sheath is fitted onto the main tube and houses the second wing. This solution, through the cooperation of the stent body, the delivery unit, and the guidewire, enables the plastic biliary stent to reach the target position during delivery, and the first and second wing can gradually unfold in a predetermined order and embed into the surrounding tissue for positioning.

[0004] The biliary stent in the above solution can open up the pancreatic and biliary tract blockage during installation, but if internal blockage occurs during subsequent use, a new stent needs to be installed or the stent position needs to be adjusted, which increases the patient's pain and financial burden. Summary of the Invention

[0005] Therefore, it is necessary to provide a drug-targeted bile and pancreatic duct stent and its usage method to address the problem of current bile and pancreatic duct stents becoming blocked during use and needing to be replaced or moved, causing patient suffering and financial burden.

[0006] The above objectives are achieved through the following technical solutions: A drug-targeted delivery biliary and pancreatic duct stent, comprising: The stent body has a guide wire and an anti-retraction valve at its front end and an anti-backflow valve at its rear end. The stent body is hollow inside. A drug storage component is located inside the stent body and is configured to release medication to break down the blockage when the stent body becomes blocked.

[0007] Furthermore, the drug storage assembly includes a drug storage chamber and spikes. The drug storage chamber is located on the side wall of the support body, and the spikes are located inside the drug storage chamber. The spikes are radially distributed along the drug storage chamber, and the inner wall of the drug storage chamber is elastic and can be pierced by the spikes.

[0008] Furthermore, the support body includes an inner tube and an outer tube, with the drug storage chamber formed between the inner tube and the outer tube. The spikes are arranged radially along the outer tube, with one end of the spikes fixedly disposed on the inner wall of the outer tube, and the other end of the spikes having a pointed tip and being a predetermined distance from the inner tube.

[0009] Furthermore, the inner tube and the outer tube have multiple independent cavities along the axial direction, and each of the multiple independent cavities is a drug storage chamber.

[0010] Furthermore, the medicine storage compartment includes multiple sub-compartments, which are evenly distributed along the circumference of the cavity. Each sub-compartment is equipped with the spikes, and the length of the spikes increases sequentially in a clockwise or counterclockwise direction along the circumference of the outer tube.

[0011] Furthermore, multiple partition strips are provided between the inner tube and the outer tube, with one end of each partition strip fixedly connected to the outer circumference of the inner tube and the other end of each partition strip fixedly connected to the inner circumference of the outer tube.

[0012] Furthermore, multiple check valves are provided on the side wall of the outer tube along the axial direction, with the multiple check valves arranged in pairs and evenly distributed along the axial direction.

[0013] Furthermore, the outer side of the stent body is coated with a therapeutic solution.

[0014] Furthermore, a drug carrier is disposed on the outer side of the stent body, and the therapeutic solution is located on the drug carrier.

[0015] This invention also provides a method for using a drug-targeted delivery bile and pancreatic duct stent, comprising the following steps: Step S100: Perform a preoperative examination on the patient to determine the location of any blockage in the patient's bile duct or pancreatic duct, and fill the drug storage assembly with medication. Step S200: Deliver the stent body to the location of the blockage in the bile duct or pancreatic duct; Step S300: When a blockage occurs inside the stent body, the drug storage component releases drugs to break down the blockage. Step S400: Remove the stent body after the treatment cycle is completed.

[0016] The beneficial effects of this invention are: This invention incorporates a drug-storage component inside the stent. When the stent becomes blocked by gallstones, mucus, or other obstructions, the internal pressure increases, causing the drug-storage component to release medication. This medication acts directly on the blockage site, automatically breaking down the blockage without additional intervention. This avoids the inconvenience of surgical replacement required after a traditional stent becomes blocked, reducing patient suffering and medical costs.

[0017] This invention addresses secondary blockages at different locations by setting multiple independent drug storage chambers between the inner and outer tubes of the stent body, covering the entire length of the stent. Each drug storage chamber is further divided into multiple circumferentially distributed sub-drug chambers, with gradually varying spike lengths within each sub-drug chamber. The first blockage triggers drug release from the sub-drug chamber corresponding to the longest spike, while subsequent blockages trigger drug release from the sub-drug chamber with shorter spikes, enabling multiple drug releases from the same location. This multi-layered design significantly extends the effective lifespan of the stent and reduces the recurrence rate of blockages.

[0018] This invention involves placing a drug carrier on the outside of the stent body. The drug carrier is coated with an anti-proliferative drug, an anti-inflammatory drug, or an antibacterial drug. After implantation, the drug is continuously released locally into the bile and pancreatic ducts. The anti-proliferative drug can inhibit excessive mucosal proliferation, the anti-inflammatory drug can relieve inflammation and edema caused by foreign body stimulation, and the antibacterial drug can prevent infection. This reduces the risk of secondary blockage from the root cause and also assists in the treatment of bile and pancreatic duct inflammation. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of a drug-targeted delivery bile and pancreatic duct stent provided in an embodiment of the present invention; Figure 2 This is a view from another angle of a drug-targeted delivery bile and pancreatic duct stent provided in an embodiment of the present invention; Figure 3 for Figure 2 A cross-sectional view along AA of a drug-targeted delivery bile and pancreatic duct stent provided in one embodiment; Figure 4 for Figure 3 A magnified view of the X portion of the drug storage compartment of the drug-targeted delivery bile and pancreatic duct stent provided in one embodiment, when it is undisturbed; Figure 5 for Figure 3 A magnified view of a portion of the drug storage compartment of a bile and pancreatic duct stent for targeted drug delivery provided in one embodiment of the invention, when the compartment ruptures. Figure 6 for Figure 4 A partially enlarged view of the Y portion of a drug-targeted delivery bile and pancreatic duct stent provided in one embodiment; Figure 7 for Figure 2 A cross-sectional view along the BB of a drug-targeted delivery bile duct stent provided in one embodiment; Figure 8 for Figure 7A partially enlarged view of the Z portion of a drug-targeted delivery bile and pancreatic duct stent provided in one embodiment.

[0020] in: 100. Stent body; 110. Anti-retrograde valve; 120. Anti-retrograde valve; 130. Inner tube; 140. Outer tube; 141. Anti-retrograde valve; 150. Drug carrier; 200. Medicine storage compartment; 210. Sub-medicine compartment; 220. Spikes; 230. Divider strip. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0022] The component designations used in this document, such as "first" and "second," are merely for distinguishing the described objects and do not have any sequential or technical meaning. The terms "connection" and "linkage" used in this invention, unless otherwise specified, include both direct and indirect connections (linkages). It should be understood that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are used only for the convenience of describing the invention and simplifying the description. They do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the invention.

[0023] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0024] The following reference Figures 1-8 This invention describes a drug-targeted delivery bile and pancreatic duct stent provided by the present invention.

[0025] A drug-targeted bile and pancreatic duct stent, suitable for targeted treatment of bile duct or pancreatic duct obstruction, includes a stent body 100. The stent body 100 is hollow to allow fluid to pass through. A guide wire (not shown in the figure) and an anti-retraction valve 110 are provided at the front end of the stent body 100. The guide wire is used to guide the stent body 100 into the obstructed bile duct or pancreatic duct. The anti-retraction valve 110 at the front end of the stent body 100 does not affect the entry of the stent body 100 into the bile duct or pancreatic duct. After the stent body 100 moves to the designated position to open the obstructed bile duct or pancreatic duct, the anti-retraction valve 110 at the front end of the stent body 100 can prevent the stent body 100 from retracting, thereby positioning the stent body 100 in the bile duct or pancreatic duct. An anti-reflux valve 120 is provided at the rear end of the stent body 100 to prevent the backflow of bile or pancreatic juice. In existing technologies, stents can be moved to a designated position to open up blocked bile ducts or pancreatic ducts, thereby resolving the blockage. However, if internal blockage occurs during subsequent use, a new stent needs to be installed or the stent position adjusted, increasing patient suffering and financial burden.

[0026] Based on this, the present invention provides a drug storage component inside the stent body 100. The drug storage component can store drugs, which can break down blockages inside the stent body 100. When the stent body 100 becomes blocked during subsequent use, the drug storage component will release the stored drugs, which will break down the blockages and clear the blockage. This can increase the service life of the stent body 100 and eliminate the need to replace the stent body 100 or move its position within a certain period of time, thereby reducing the patient's pain and economic burden.

[0027] It should be noted that obstructions in the bile duct or pancreatic duct are generally caused by gallstones and mucus. If the obstruction is gallstones, medications that dissolve gallstones, such as ursodeoxycholic acid and chenodeoxycholic acid, can be used. These medications alter the composition of bile, reducing cholesterol saturation and promoting the dissolution of pigment gallstones. If the obstruction is a mucus plug or inflammatory secretion, pancreatic enzyme preparations (such as enteric-coated pancreatic enzyme capsules) and mucus dissolving agents (such as acetylcysteine) can be used. Pancreatic enzymes help degrade the protein components in the mucus, and acetylcysteine ​​disrupts the mucopolysaccharide structure of the mucus, promoting the excretion of secretions. Therefore, these medications (considering that various medications may interfere with each other when placed together, only one medication for dissolving gallstones and one for dissolving mucus is used) can be packed into a drug reservoir. When an obstruction occurs, the drug reservoir releases these medications, which can dissolve both gallstones and mucus, thus achieving targeted drug delivery and reducing obstruction.

[0028] Specifically, the drug storage component in this embodiment includes a drug storage chamber 200 and spikes 220. The drug storage chamber 200 is disposed on the side wall of the support body 100, while the spikes 220 are disposed inside the drug storage chamber 200. When the support body 100 is blocked, the side wall of the support body 100 will be subjected to greater pressure. At this time, the drug storage chamber 200 will be punctured by the spikes 220 when subjected to the squeezing force. The drug in the drug storage chamber 200 will be discharged from the puncture position of the spikes 220 and come into contact with the blockage at the blockage position. The drug can decompose the blockage.

[0029] It is understandable that, since the stent body 100 opens up the location of the blockage in the bile duct or pancreatic duct, bile or pancreatic juice will flow through the inside of the stent body 100. If there is a blockage in the bile or pancreatic juice, the blockage can easily get stuck inside the stent body 100 when it passes through. Since bile or pancreatic juice is constantly secreted, the blockage inside the stent body 100 will increase the internal pressure. The sidewall of the stent body 100 is elastic. At this time, the drug reservoir 200 on the sidewall of the stent body 100 will be under pressure and will approach the spike 220, which will then puncture it to release the drug to break down the blockage, thereby reducing the blockage inside the stent body 100.

[0030] More specifically, in this embodiment, the stent body 100 includes an inner tube 130 and an outer tube 140, forming the aforementioned drug storage chamber 200 between the inner tube 130 and the outer tube 140. A spike 220 is disposed between the inner tube 130 and the outer tube 140, arranged radially along the outer tube 140. One end of the spike 220 is fixedly connected to the inside of the outer tube 140, and the other end of the spike 220 has a pointed tip that is close to but does not contact the outer wall of the inner tube 130. A preset distance exists between them (this preset distance is the distance at which the spike 220 can contact the inner tube 130 after the inner tube 130 expands due to blockage). The inner tube 130 is used for the passage of bile or pancreatic juice. The inner tube 130 is elastic; when a blockage occurs inside the inner tube 130, the pressure inside increases, causing the inner tube 130 to expand radially outwards. The inner tube 130 expands until it contacts the tip of the spike 220, at which point it will be punctured. Specifically, as shown... Figures 4 to 5 As shown in the state change, the drug between the inner tube 130 and the outer tube 140 is discharged through the puncture point of the spike 220.

[0031] In a further embodiment, to further improve the service life of the stent body 100, the inner tube 130 and the outer tube 140 of the present invention have multiple independent cavities along the axial direction. Each of these independent cavities is filled with medication and is equipped with the aforementioned spikes 220. In other words, each of the multiple independent cavities serves as a medication reservoir 200. During the use of the stent body 100, since the inner tube 130 has a certain length, the location of blockages within the inner tube 130 is random and does not occur only once. If only one medication reservoir 200 is provided within the stent body 100, it can only overcome one blockage, and subsequent blockages at other locations cannot be decomposed. Therefore, this embodiment, by providing multiple medication reservoirs 200 along the axial direction, can promptly decompose blockages at different locations, thereby increasing the service life of the stent body 100.

[0032] It is understandable that the multiple drug reservoirs 200 are evenly distributed along the axial direction, ensuring that all locations inside the stent body 100 are covered by the drug reservoirs 200. When a blockage occurs in one area of ​​the inner tube 130, the increased pressure in the blocked area causes the inner tube 130 in that area to expand radially outward and come into contact with the tip of the spike 220. The tip of the spike 220 punctures the inner tube 130, causing the drug reservoir 200 in that area to discharge the drug. The drug breaks down the blockage in that area. When other areas of the inner tube 130 become blocked, the increased pressure in the blocked area causes the inner tube 130 in that area to expand radially outward and come into contact with the tip of the spike 220. The spike 220 punctures the inner tube 130 in that area, causing the drug reservoir 200 in that area to discharge the drug. When blockages occur in different areas subsequently, the drug reservoirs 200 in different areas will discharge the drug to break down the blockage, thereby effectively increasing the service life of the stent body 100.

[0033] In a further embodiment, the same area in the inner tube 130 may experience multiple blockages. If all medication is discharged after a single blockage in the same area, subsequent blockages will prevent the dissolution of the blockage, necessitating a new stent replacement. Therefore, in this embodiment, the drug storage compartment 200 in the same area includes multiple sub-compartments 210. These sub-compartments 210 are evenly distributed circumferentially along the cavity between the inner tube 130 and the outer tube 140. Each sub-compartment 210 contains the aforementioned spikes 220. The number of sub-compartments 210 determines the number of times the blockage can be dissolved in that area. In this embodiment, there are three sub-compartments 210. To prevent simultaneous discharge of medication from all three sub-compartments 210, the lengths of the spikes 220 in the three sub-compartments 210 are different. The length of the spikes 220 increases sequentially clockwise or counterclockwise along the circumference of the outer tube 140, ensuring that the medication is not discharged simultaneously. The distance between the tip of the spike 220 in the sub-drug chamber 210 and the inner tube 130 varies. The spike 220 closest to the inner tube 130 (i.e., the longest spike 220) will puncture the inner tube 130 first when a blockage occurs. The drug in this sub-drug chamber 210 will be discharged to dissolve the blockage. If a second blockage occurs in the same area, the spike 220 second closest to the inner tube 130 will puncture the corresponding sub-drug chamber 210 when a second blockage occurs, thus dissolving the drug in this sub-drug chamber 210. Similarly, if a third blockage occurs in the same area, the spike 220 furthest from the inner tube 130 (i.e., the shortest spike 220) will puncture the corresponding sub-drug chamber 210 when a third blockage occurs, thus dissolving the blockage for the third time. This allows the blockage in the same area to be dissolved multiple times, avoiding the situation where the blockage cannot be dissolved when there are multiple blockages in the same area.

[0034] It should be noted that if the blockage is severe, and the spike 220 cannot break down the blockage by piercing one sub-drug chamber 210, as the blockage time increases and the bile duct or pancreatic duct continues to secrete bile and pancreatic juice, the pressure in the blocked area continues to increase. The inner tube 130 of the blocked area continues to expand radially outward, causing another spike 220 to pierce another sub-drug chamber 210. The drug in the newly pierced sub-drug chamber 210 continues to break down the blockage. If it still cannot break down the blockage, a new sub-drug chamber 210 is pierced. In this embodiment, only three sub-drug chambers 210 are used as an example, and the number of sub-drug chambers 210 is not limited. For example, there can be four or five, etc.

[0035] Specifically, in this embodiment, multiple partition strips 230 are provided in each of the multiple medicine storage compartments 200 between the inner tube 130 and the outer tube 140, such as... Figure 8As shown, there are three dividing strips 230, which divide the medicine storage compartment 200 into three sub-compartments 210. One end of the dividing strip 230 is fixedly connected to the inner circumference of the outer tube 140, and the other end of the dividing strip 230 is fixedly connected to the outer circumference of the inner tube 130. The number of dividing strips 230 determines the number of sub-compartments 210, and the number of dividing strips 230 is not specifically limited here.

[0036] In a further embodiment, the outer tube 140 of the present invention is provided with a plurality of check valves 141 on its sidewall. The plurality of check valves 141 are arranged in pairs, and each pair of check valves 141 is axially and evenly distributed on the sidewall of the outer tube 140. The check valves 141 are used to prevent bile or pancreatic juice in the inner tube 130 from flowing back.

[0037] It should be noted that, as Figure 3 and Figure 4 As shown, the outer tube 140 in this embodiment is not continuous, but has multiple segments. Each segment of the outer tube 140 forms a drug storage chamber 200 with the inner tube 130. Both ends of the outer tube 140 are tapered, and the small end of the tapered tube is fixedly connected to the outer periphery of the inner tube 130. The aforementioned anti-retrograde valve 141 is provided at the connection position between the small end of the outer tube 140 and the inner tube 130. A through hole is provided on the inner tube 130 at the position corresponding to the anti-retrograde valve 141. The axial cross-sections of the inner tube 130 and the outer tube 140 are similar to parallelograms. One end of the outer tube 140 is a concave tapered shape, and the other end of the outer tube 140 is a convex tapered shape. The concave tapered end of an adjacent outer tube 140 is adapted to the convex tapered shape of another outer tube 140, so that the whole formed by multiple outer tubes 140 can be bent to adapt to different shapes of bile ducts or pancreatic ducts.

[0038] In a further embodiment, the outer side of the stent body 100 of the present invention is coated with a therapeutic solution. The therapeutic solution includes antiproliferative drugs, such as paclitaxel, rapamycin and their derivatives. Antiproliferative drugs are used to inhibit excessive tissue proliferation. Excessive proliferation of mucosal or smooth muscle cells in the narrowed part of the bile duct and pancreatic duct is the main cause of blockage of the stent body 100, and antiproliferative drugs can inhibit this process. Anti-inflammatory drugs, such as glucocorticoids, are used to reduce local inflammatory response. The implantation of the stent body 100 is a foreign body stimulation, which can cause inflammation. Anti-inflammatory drugs can relieve inflammatory edema and reduce the accumulation of secretions. The therapeutic solution also includes antibacterial drugs, which are used to prevent infection of the bile duct and pancreatic duct.

[0039] It should be noted that applying a therapeutic solution to the outside of the stent body 100 can inhibit the proliferation of the bile duct and pancreatic duct and has anti-inflammatory effects, which will reduce the risk of blockage of the stent body 100 during short-term use.

[0040] Specifically, to facilitate the coating of these drugs on the outer side of the stent body 100, a drug carrier 150 is provided on the outer periphery of the outer tube 140 in this embodiment. Common types of drug carriers 150 include liposomes, microspheres, and nanocarriers. The drug carrier 150 is used to carry the therapeutic solution and prevent the therapeutic solution from becoming ineffective.

[0041] The specific working process of the drug-targeted delivery bile and pancreatic duct stent provided by the present invention will be described in conjunction with the above embodiments: Filling with medication: Various preoperative examinations are performed on the patient to determine the location of the blockage in the bile duct or pancreatic duct, and the medication to break down the blockage is loaded into each sub-drug compartment 210. At the same time, the therapeutic solution is coated on the drug carrier 150 of the outer tube 140.

[0042] Conveyor support body 100: Medical staff use interventional devices to deliver the stent body 100 into the bile duct or pancreatic duct to be supported. The anti-retraction valve 110 on the stent body 100 does not affect the advancement of the stent body 100 in the bile duct or pancreatic duct. When the stent body 100 moves to the designated position in the bile duct or pancreatic duct, the anti-retraction valve 110 can position the stent body 100 to prevent dislodgement. The stent body 100 opens the obstruction in the bile duct or pancreatic duct, and the bile in the bile duct or the pancreatic juice in the pancreatic duct will pass through the inner tube 130 of the stent body 100, thereby playing a role in unblocking and guiding. In addition, the anti-backflow valve 120 at the rear end of the stent body 100 can prevent the bile or pancreatic juice that has passed through the stent body 100 from flowing back into the stent body 100.

[0043] When blockage occurs during the use of the support body 100: If obstruction caused by secretions from the bile duct or pancreatic duct blocks the inner tube 130 of the stent body 100, the pressure on the inner tube 130 continuously increases, causing the obstructed area of ​​the inner tube 130 to expand radially outward. During this expansion, the inner tube 130 can contact the tip of the spike 220 within the sub-drug reservoir 210, causing the sub-drug reservoir 210 to rupture. The medication within the sub-drug reservoir 210 is then released and acts on the obstruction, breaking it down and clearing the blockage. Since multiple sub-drug reservoirs 210 are distributed in the same area, if the medication in one sub-drug reservoir 210 is insufficient to break down the obstruction... When blockage occurs, the inner tube 130 of the blocked area continues to expand, causing the second sub-drug chamber 210 to rupture. The second sub-drug chamber 210 discharges medication to break down the blockage. If blockage recurs after the blockage in that area has been broken down, other sub-drug chambers 210 in that area will discharge medication to break down the blockage, thereby increasing the service life of the stent body 100. Similarly, if blockage occurs in other areas, multiple sub-drug chambers 210 in those areas will also discharge medication to break down the blockage, reducing the frequency of blockage in the stent body 100 during subsequent use.

[0044] Remove the support body 100: After the patient's treatment cycle is completed, medical staff will remove the stent body 100 with the assistance of other medical devices.

[0045] This invention also provides a method for using a drug-targeted delivery bile and pancreatic duct stent, comprising the following steps: Step S100: Perform a preoperative examination on the patient to determine the location of any blockage in the patient's bile duct or pancreatic duct, and fill the drug storage assembly with medication. Step S200: Deliver the stent body 100 to the location of the blockage in the bile duct or pancreatic duct; In step S300, when a blockage occurs inside the stent body 100, the drug storage component releases drugs to break down the blockage. Step S400: Remove the stent body 100 after the treatment cycle is completed.

[0046] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0047] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A drug-targeted bile and pancreatic duct stent, characterized in that, include: The stent body has a guide wire and an anti-retraction valve at its front end and an anti-backflow valve at its rear end. The stent body is hollow inside. A drug storage component is located inside the stent body and is configured to release drugs to break down the blockage when the stent body becomes blocked. The drug storage assembly includes a drug storage chamber and spikes. The drug storage chamber is located on the side wall of the support body, and the spikes are located inside the drug storage chamber. The spikes are radially distributed along the drug storage chamber. The inner wall of the drug storage chamber is elastic and can be pierced by the spikes. The support body includes an inner tube and an outer tube, and the drug storage chamber is formed between the inner tube and the outer tube. The spikes are arranged radially along the outer tube. One end of the spikes is fixedly disposed on the inner wall of the outer tube, and the other end of the spikes has a pointed tip and is at a predetermined distance from the inner tube. The inner tube and the outer tube have multiple independent cavities along the axial direction, and each of the multiple independent cavities is a drug storage chamber; The medicine storage compartment includes multiple sub-compartments, which are evenly distributed along the circumference of the cavity. Each sub-compartment is equipped with the spikes, and the length of the spikes increases sequentially in a clockwise or counterclockwise direction along the circumference of the outer tube.

2. The drug-targeted delivery bile and pancreatic duct stent according to claim 1, characterized in that, Multiple partition strips are provided between the inner tube and the outer tube. One end of the partition strips is fixedly connected to the outer circumference of the inner tube, and the other end of the partition strips is fixedly connected to the inner circumference of the outer tube.

3. The drug-targeted delivery bile and pancreatic duct stent according to claim 1, characterized in that, Multiple anti-reverse valves are provided on the side wall of the outer tube along the axial direction. The multiple anti-reverse valves are arranged in pairs and are evenly distributed along the axial direction.

4. The drug-targeted delivery bile and pancreatic duct stent according to claim 1, characterized in that, The outer side of the stent body is coated with a therapeutic solution.

5. The drug-targeted delivery bile and pancreatic duct stent according to claim 4, characterized in that, A drug carrier is disposed on the outer side of the stent body, and the therapeutic solution is located on the drug carrier.

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