A covered stent and delivery system
By designing the supporting framework and membrane structure of the covered stent, the problem of inserting an additional plastic stent in gallbladder-preserving stone removal surgery was solved, enabling the smooth outflow of bile and pancreatic juice, and reducing the cost and complexity of the surgery.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- MICRO-TECH (NANJING) CO LTD
- Filing Date
- 2025-01-21
- Publication Date
- 2026-05-29
AI Technical Summary
Current techniques require the placement of an additional plastic stent in the common bile duct during gallbladder-preserving stone removal surgery to aid in drainage, which increases the cost and complexity of the procedure.
A covered stent was designed, including a support frame and a membrane. The support frame is a cylindrical structure with a hollowed-out periphery. The membrane covers part of the support frame to form drainage mesh. After expansion, the stent forms a temporary channel between the duodenal papilla and the gallbladder, allowing bile and pancreatic juice to pass through, thus avoiding the need for additional plastic stent placement.
This allows for the smooth outflow of bile and pancreatic juice, reducing surgical costs and complexity, and avoiding the need for additional plastic stents.
Smart Images
Figure CN224292054U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of medical device technology, and in particular to a covered stent and its implantation system. Background Technology
[0002] The gallbladder is located below the liver. A normal gallbladder is about 8-12 cm long, 3-5 cm wide, and has a capacity of about 30-60 ml. Connected to the common bile duct via the bile duct, the gallbladder functions to store bile, concentrate bile, secrete mucus, and empty itself, making it a vital digestive and immune organ. Gallstones are a common type of cholelithiasis. While a small percentage of asymptomatic gallstones can be monitored, most require surgical treatment. The surgical procedure for gallstones is cholecystectomy, which can be broadly divided into two types: open surgery and minimally invasive surgery, primarily laparoscopic surgery. During gallbladder surgery, the relationships between important structures such as the cystic duct, common bile duct, common hepatic duct, and left and right hepatic ducts must first be clearly identified. Then, the gallbladder vessels are severed, the cystic duct is ligated and cut, and finally, the gallbladder is removed from the gallbladder bed of the liver.
[0003] Because gallbladder removal can lead to numerous side effects, such as indigestion, diarrhea, bloating, bile reflux gastritis, common bile duct stone formation, and even an increased risk of colon cancer, gallbladder-preserving stone removal surgery is receiving increasing attention in the medical field. In some gallbladder-preserving stone removal surgeries, a stent needs to be placed outside the gallbladder-cystic duct-common bile duct-duodenal papilla. Once the stent has fully expanded, a channel for stone removal is created. Stents typically include uncovered stents and fully covered stents. Uncovered stents are more likely to irritate the duct walls; while fully covered stents can compress the common bile duct, preventing bile from flowing out and reaching the papilla. Therefore, it is necessary to place an additional plastic stent within the common bile duct to aid drainage, increasing the cost and complexity of the surgery. Utility Model Content
[0004] The first objective of this invention is to provide a covered stent to solve the technical problem that existing techniques require the placement of an additional plastic stent in the common bile duct to aid in drainage during gallbladder-preserving stone removal, which increases surgical costs and complexity.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A membrane-covered scaffold includes a support frame and a membrane, wherein:
[0007] The supporting frame is a cylindrical structure with a hollowed-out circumference, which can be radially compressed and expanded.
[0008] The film covers a portion of the support frame, forming drainage mesh in the areas of the support frame not covered by the film.
[0009] Furthermore, when the supporting frame is expanded, the aperture of the drainage mesh ranges from 1 to 4 mm.
[0010] Furthermore, the drainage mesh is rhomboid, rectangular, circular, or other polygonal.
[0011] Furthermore, the number of drainage mesh holes is multiple and they are evenly distributed in an array on the circumferential surface of the support frame;
[0012] Alternatively, the number of drainage mesh holes is multiple and they are arranged in a spiral pattern on the circumferential surface of the support frame.
[0013] Furthermore, the common bile duct, cystic duct, and gallbladder are sequentially inserted from outside the duodenal papilla, and the drainage mesh is provided on the supporting frame at the interface positions corresponding to the gallbladder, the common bile duct and the common hepatic duct, and the interface position between the common bile duct and the pancreatic duct.
[0014] Furthermore, the film is wrapped around the support frame in a grid or stripe pattern.
[0015] Furthermore, the support frame has a proximal end and a distal end arranged opposite each other along the axial direction, and a pair of tantalum marks are provided at predetermined intervals from the proximal end to the distal end of the support frame.
[0016] Furthermore, the outer diameter of the support frame when it is extended is in the range of 6-11 mm;
[0017] The length of the support frame when it is extended ranges from 70 to 130 mm.
[0018] The second objective of this invention is to provide an implantation system comprising the covered stent described in any of the preceding claims.
[0019] Furthermore, it also includes an implanter for placing the covered stent into the human body, the implanter having a proximal end and a distal end arranged opposite each other along the axial direction, the distal end of the implanter being provided with an electrical cutting structure for cutting open a narrow region.
[0020] The beneficial effects of this utility model are:
[0021] This invention provides a covered stent and its placement system. The covered stent includes a supporting frame and a membrane. The supporting frame is a cylindrical structure with a perforated circumferential surface, capable of radial compression and expansion. The membrane covers a portion of the supporting frame, forming drainage mesh in the areas of the supporting frame not covered by the membrane. During use, the covered stent is first inserted sequentially through the duodenal papilla from the outside in a fully contracted state, along with the common bile duct, cystic duct, and gallbladder. Then, it expands radially to open the duodenal papilla, common bile duct, cystic duct, and gallbladder, forming a temporary channel between the duodenal papilla and the gallbladder. Because the membrane covers part of the supporting framework, drainage holes are formed in the areas of the supporting framework not covered by the membrane. Bile from the gallbladder, bile from the common hepatic duct, and pancreatic juice from the pancreatic duct can enter the interior of the covered stent through the drainage holes and reach the duodenal papilla. This avoids the common bile duct being compressed by the stent, which would prevent bile and pancreatic juice from flowing out of the common bile duct and reaching the duodenal papilla. At the same time, there is no need to place an additional plastic stent in the common bile duct to help with drainage, thus reducing surgical costs and the complexity of the surgery. Attached Figure Description
[0022] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0023] Figure 1 A three-dimensional schematic diagram of the film-coated support provided in an embodiment of this utility model;
[0024] Figure 2 for Figure 1 Enlarged view at point A;
[0025] Figure 3 A front view of the film-coated support provided in an embodiment of this utility model;
[0026] Figure 4 This is a schematic diagram showing the position of the covered stent provided in this embodiment of the invention when placed in the human body.
[0027] icon:
[0028] 1-Supporting skeleton; 2-Thin film; 3-Drainage mesh; 4-Tantalum marker;
[0029] 100 - Duodenal papilla; 200 - Common bile duct; 300 - Cystic duct; 400 - Gallbladder; 500 - Common hepatic duct; 600 - Pancreatic duct. Detailed Implementation
[0030] The technical solution of this utility model will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.
[0031] It should be noted that in the description of this utility model, the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used solely for the convenience of describing this utility model and for simplifying the description, and 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. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0032] It should be noted that in the description of this utility model, the terms "connection" and "installation" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or a connection through an intermediate medium; they can refer to a mechanical connection or an electrical connection. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.
[0033] To address the technical problem that existing techniques for cholecystolithotomy using covered stents require the placement of an additional plastic stent within the common bile duct to aid drainage, increasing surgical costs and complexity, the first aspect of this utility model provides a covered stent, as described above. Figures 1 to 3 The film-coated support includes a support frame 1 and a film 2, wherein:
[0034] The supporting frame 1 is a cylindrical structure with a hollowed-out circumference, which can be radially compressed and expanded;
[0035] The film 2 covers part of the support frame 1, and drainage mesh 3 is formed in the area of the support frame 1 that is not covered by the film 2.
[0036] During the use of the above-mentioned film-coated stent, combined with Figure 4First, with the covered stent in a fully contracted state, the common bile duct 200, cystic duct 300, and gallbladder 400 are sequentially inserted from outside the duodenal papilla 100 (as shown by the dotted lines in the drawing). Then, radial expansion is performed to open the duodenal papilla, common bile duct 200, cystic duct 300, and gallbladder 400, forming a temporary channel between the duodenal papilla and gallbladder 400. Because the membrane 2 covers part of the supporting skeleton 1 (i.e., the covered stent is a partially covered structure), drainage mesh 3 is formed in the area of the supporting skeleton 1 that is not covered by the membrane 2. Bile in the gallbladder 400, bile in the common hepatic duct 500, and pancreatic juice in the pancreatic duct 600 can enter the interior of the covered stent through the drainage mesh 3 and reach the duodenal papilla. This avoids the common bile duct 200 being compressed by the stent, which would prevent bile and pancreatic juice from flowing out of the common bile duct 200 and reaching the duodenal papilla. At the same time, there is no need to place an additional plastic stent in the common bile duct 200 to help with drainage, thereby reducing surgical costs and the complexity of the surgery.
[0037] The covered stent provided in this embodiment can be inserted into an implanter with an outer diameter ranging from 2.16 mm to 2.83 mm (preferably 2.5 mm), ensuring that the implanter can be guided by a guidewire with a diameter ranging from 0.5 mm to 0.89 mm. Due to the small outer diameter of the implanter, it can more easily pass through the patient's common bile duct 200, cystic duct 300, spiral fold, and gallbladder neck, and enter the gallbladder 400. Then, the covered stent is inserted, establishing a temporary channel between the gallbladder 400 and the duodenal papilla, thereby forming a channel for surgical instruments to enter and exit within the supporting framework 1. This facilitates the entry of instruments such as choledochoscopes into the gallbladder for lithotripsy and stone removal, eliminating the need for gallbladder resection. Furthermore, the covered stent provided in this embodiment can also be applied to gallbladder polyp removal surgery and gallbladder biopsy via natural orifice.
[0038] In some embodiments, such as Figures 1 to 3 As shown, the drainage mesh 3 is a plurality of holes arranged in a spiral pattern on the circumferential surface of the support frame 1; or, the drainage mesh 3 is a plurality of holes arranged in an array uniformly distributed on the circumferential surface of the support frame 1. For example, the plurality of drainage mesh 3 are divided into at least two spaced-apart groups of holes, each group arranged in a spiral pattern around the support frame 1; or, the plurality of drainage mesh 3 are arranged in an array along the axial and circumferential directions of the support frame 1.
[0039] Figures 1 to 3In the illustrated embodiment, multiple drainage mesh openings 3 are evenly arranged in a spiral pattern on the circumferential surface of the supporting frame 1, giving the entire covered stent a sieve-like covered structure. Bile and pancreatic juice can flow into the interior of the supporting frame 1 through the sieve-like openings of the stent and then flow out of the duodenum along the supporting frame 1. Because the drainage mesh openings 3 are evenly distributed on the circumferential surface of the supporting frame 1, the inflow of bile and pancreatic juice in various areas is facilitated, achieving an excellent drainage effect.
[0040] Based on the above structure, the thin film 2 is wrapped around the support frame 1 in a grid or stripe pattern.
[0041] Figures 1 to 3 The embodiment shown is in which the film 2 is covered on the support frame 1 in a grid pattern. In this embodiment, each gap of the film 2 forms a drainage mesh 3, thereby forming a plurality of uniformly distributed drainage mesh 3 on the periphery of the support frame 1.
[0042] In the embodiment where the film 2 is striped and covered on the support frame 1, the film 2 includes a plurality of film rings spaced apart along the axial direction of the support frame 1, and drainage mesh 3 is formed in the gap between two adjacent film rings.
[0043] Preferably, the film 2 is wrapped around the support frame 1 in a grid pattern, which can increase the coverage area without affecting the discharge of bile and pancreatic juice.
[0044] In other embodiments, the drainage mesh 3 may be provided only at the interface locations on the support frame 1 corresponding to the gallbladder 400, the common bile duct 200 and the common hepatic duct 500, and the interface location between the common bile duct 200 and the pancreatic duct 600. Specifically, a mesh-like film 2 may be provided only at the portion of the support frame 1 corresponding to the gallbladder 400, the interface locations between the common bile duct 200 and the common hepatic duct 500, and the interface location between the common bile duct 200 and the pancreatic duct 600 (or the film 2 may be omitted), while a complete film 2 is provided at other locations on the support frame 1. The advantage of this structure is that it can increase the coverage area.
[0045] In some embodiments, the support frame 1 is woven from nickel-titanium wire to form a straight cylindrical structure with a hollowed-out circumference, and the cross-section of the support frame 1 is circular. The outer diameter of the support frame 1 when it is extended ranges from 6 to 11 mm; for example, the outer diameter of the support frame 1 when it is extended can be 6 mm, 8 mm, 10 mm, 11 mm, etc. The length of the support frame 1 when it is extended ranges from 70 to 130 mm; for example, the length of the support frame 1 when it is extended can be 70 mm, 90 mm, 100 mm, 110 mm, 120 mm, etc.
[0046] In the above structure, the supporting frame 1 has a cylindrical shape, which makes it easier to adapt to the shape of the bile duct and ensures a balance in the supporting strength and supporting force. Setting the outer diameter of the supporting frame 1 when expanded to 6-11 mm prevents it from being too small to form a suitable temporary channel within the body, thus affecting the passage of surgical instruments and stones, while also preventing it from being too large to hinder its insertion during surgery. Setting the length of the supporting frame 1 when expanded to 70-130 mm effectively forms a temporary channel between the bile duct orifice and the gallbladder 400, avoiding the problem of the supporting frame 1 being too long or too short.
[0047] Continue to refer to Figure 3 The support frame 1 has a proximal end and a distal end arranged axially opposite each other. A pair of tantalum markers 4 are provided at predetermined intervals from the proximal end to the distal end of the support frame 1. Taking a length of 100mm when the support frame 1 is expanded in vitro at room temperature as an example, a pair of tantalum markers 4 are installed at both ends of the support frame 1 and at intervals of 20mm starting from one end, for a total of six pairs. The tantalum markers 4 can be displayed under fluoroscopy to accurately identify the insertion position of the covered stent.
[0048] Furthermore, a retrieval line is provided at the proximal end of the support frame 1. Specifically, the retrieval line is located at the edge of the proximal end of the support frame 1. When it is necessary to remove the covered stent from the patient's body, the retrieval line is grasped by the retrieval device to remove the support frame 1 from the patient's body, which facilitates the operation.
[0049] In some embodiments, the film 2 is made of silicone, latex, or a polymer (e.g., polytetrafluoroethylene). During the fabrication of the coated support, a complete film 2 can be formed on the support frame 1 first, and then multiple holes can be peeled out on the film 2 to form drainage mesh 3.
[0050] In some embodiments, when the support frame 1 is extended, the aperture of the drainage mesh 3 ranges from 1 to 4 mm. For example, the aperture of the drainage mesh 3 is 1 mm, 2 mm, 2.5 mm, 2.7 mm, 3 mm, or 4 mm. The drainage mesh 3 can be rhomboid, rectangular, circular, or other polygonal.
[0051] Setting the aperture range of the drainage mesh 3 to 1-4 mm allows bile from the gallbladder, bile from the common hepatic duct 500, and pancreatic juice from the pancreatic duct 600 to smoothly enter the support frame 1, while also giving the support frame 1 a larger coverage area.
[0052] A second aspect of this utility model provides an implantation system, which includes the covered stent described in any of the above embodiments; it also includes an implanter for implanting the covered stent into the human body, the implanter having a proximal end and a distal end arranged opposite each other along the axial direction, and the distal end of the implanter having an electrocautery structure for cutting open a narrow area. Because the distal end of the implanter has an electrocautery function, when the implanter enters a narrow location such as the gallbladder neck along the guide wire, electricity can be applied to cut open the narrow area, facilitating the implanter's entry into the gallbladder 400 through the narrow location.
[0053] The implantation system provided in this application also has at least all the technical effects of the aforementioned covered stent, which will not be repeated here.
[0054] The method of using the implantation system provided in this application includes:
[0055] Based on ERCP (Endoscopic Retrograde Cholangiopancreatography), a guidewire is inserted into the gallbladder 400° through the duodenal endoscope channel.
[0056] The implanter with the covered stent is placed along the guidewire into the gallbladder 400, cystic duct 300, common bile duct 200 and duodenal papilla 100, and then the covered stent is released.
[0057] After the covered stent is fully expanded, gallbladder stone removal, gallbladder polyp removal, or gallbladder biopsy are performed under direct cholangioscopy.
[0058] The covered stent was removed after the surgery.
[0059] During the procedure, bile from the gallbladder (400), bile from the common hepatic duct (500), and pancreatic juice from the pancreatic duct (600) can enter the supporting framework (1) through the drainage mesh (3), and then flow out from the common bile duct (200) along the supporting framework and into the duodenum. Compared to traditional surgery, the covered stent and placement system provided in this application saves the cost of a plastic stent and other related drainage instruments, reduces the complexity of the surgery, and eliminates the need to consider the outflow of bile and pancreatic juice during the procedure, thus reducing the difficulty of the surgery.
[0060] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A covered stent, characterized in that, It includes a supporting framework (1) and a membrane (2), wherein: The supporting frame (1) is a cylindrical structure with a hollowed-out circumferential surface, which can be radially compressed and expanded; The film (2) covers part of the support frame (1), and drainage mesh (3) is formed in the area of the support frame (1) that is not covered by the film (2).
2. The covered stent according to claim 1, characterized in that, When the support frame (1) is opened, the aperture of the drainage mesh (3) is in the range of 1-4 mm.
3. The covered stent according to claim 1, characterized in that, The drainage mesh (3) is rhomboid, rectangular, circular, or other polygonal.
4. The covered stent according to claim 1, characterized in that, The number of drainage mesh holes (3) is multiple and they are arranged in a spiral shape on the circumferential surface of the support frame (1); Alternatively, the number of drainage mesh holes (3) is multiple and they are evenly distributed in an array on the circumferential surface of the support frame (1).
5. The covered stent according to claim 1, characterized in that, For sequential insertion of the common bile duct (200), cystic duct (300) and gallbladder (400) from outside the duodenal papilla (100), the drainage mesh (3) is provided on the support frame (1) at the interface positions of the gallbladder (400), the common bile duct (200) and the common hepatic duct (500), and the interface position of the common bile duct (200) and the pancreatic duct (600).
6. The covered stent according to claim 1, characterized in that, The film (2) is covered on the support frame (1) in a grid or stripe pattern.
7. The covered stent according to claim 1, characterized in that, The support frame (1) has a proximal end and a distal end arranged opposite each other along the axial direction. From the proximal end of the support frame (1) to the distal end of the support frame (1), a pair of tantalum marks (4) are provided at a predetermined interval.
8. The covered stent according to claim 1, characterized in that, The outer diameter of the support frame (1) when it is unfolded is in the range of 6-11mm; The length of the support frame (1) when it is extended is 70-130mm.
9. An insertion system, characterized in that, Including the covered stent as described in any one of claims 1 to 8.
10. The implantation system according to claim 9, characterized in that, It also includes an implanter for placing the covered stent into the human body, the implanter having a proximal end and a distal end arranged opposite each other along the axial direction, the distal end of the implanter being provided with an electrical cutting structure for cutting open a narrow region.