Biliary tract stent and conveying device
By designing a multi-leaf biliary stent and the synergistic effect of the delivery device's wings, the problems of limited delivery and blockage of traditional biliary stents are solved, achieving reliable expansion and drainage effects.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-07-03
- Publication Date
- 2026-03-27
AI Technical Summary
Traditional biliary stents are limited by the maximum diameter of the endoscopic device channel during delivery, and are prone to blockage after expansion, lacking effective mechanical expansion and drainage channels.
A biliary stent with multiple leaflets and folds was designed. The leaflets switch between constricted and dilated positions and are expanded with the aid of the flaps of the delivery device to form an external channel. The stent is made of a biocompatible material.
It enables reliable delivery and expansion of biliary stents, provides an external drainage channel, extends the service life of the stent, and avoids blockage problems.
Smart Images
Figure CN121752225A_ABST
Abstract
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 512,554, filed July 7, 2023, the disclosure of which is incorporated herein by reference. TECHNICAL FIELD
[0002] The present disclosure relates generally to medical devices, and more particularly, to expandable biliary stents. BACKGROUND
[0003] Partial or complete obstruction of one or more bile ducts can be remedied by the use of biliary stents. Conventional biliary stents are tubes made of plastic or metal, generally having a circular or oval cross-section. With the advent of endoscopic procedures for installing the stents, the maximum radius of each stent is limited by the maximum diameter of the endoscope device channel used to deliver them. Expandable biliary stents are known, but the smooth cylindrical shape of the stents causes the stent to fill the bile duct and quickly become clogged. There is a need for a reliable method to deliver and deploy an expandable stent with easy mechanical expansion and external channels for drainage.
[0004] The present disclosure provides medical devices that avoid the above-mentioned shortcomings of existing devices and methods of using the same. SUMMARY
[0005] The present disclosure provides design, material, method of manufacture, and use alternatives for medical devices and medical systems. In a first example, a biliary stent comprises a plurality of lobes radially alternating with a plurality of pleats; wherein each of the plurality of lobes has a first collapsed position biased inward from the pleats such that the biliary stent has a first cross-sectional diameter; and wherein each of the plurality of lobes has a second expanded position biased outward from the pleats such that the biliary stent has a second cross-sectional diameter greater than the first cross-sectional diameter.
[0006] In addition to the features of any of the above example alternatives, or as an alternative thereto, the plurality of lobes have the same length such that the stent is symmetrical.
[0007] In addition to the features of any of the above example alternatives, or as an alternative thereto, the stent is made of a biocompatible plastic.
[0008] In addition to the features of any of the above example alternatives, or as an alternative thereto, when in the second expanded position, each lobe forms a convex curve with an adjacent pleat such that once the biliary stent is expanded, the adjacent lobes form a sidewall of a channel outside of the stent.
[0009] In addition to or in lieu of the features of any of the example embodiments described above, the stent in the first, collapsed position has a cross-sectional diameter of between 1 mm and 5 mm.
[0010] In addition to or in lieu of the features of any of the example embodiments described above, the stent in the second, expanded position has a cross-sectional diameter of between 2 mm and 10 mm.
[0011] In addition to or in lieu of the features of any of the example embodiments described above, the stent has an axial length of between 2 mm and 20 mm.
[0012] In another example, a biliary stent delivery device includes a shaft sized for insertion into a patient's bile duct and one or more wings at a distal end of the shaft, wherein each wing transitions between a first, proximal orientation pointing toward a proximal end of the shaft and a second, distal orientation pointing toward a distal end of the shaft.
[0013] In addition to or in lieu of the features of any of the example embodiments described above, the shaft is loaded with an expandable biliary stent for insertion into the bile duct, the expandable stent positioned proximally of the one or more wings such that when the shaft is retracted through the loaded stent, the wings transition from the first, proximal orientation to the second, distal orientation to outwardly crush the stent, expanding the stent.
[0014] In addition to or in lieu of the features of any of the example embodiments described above, the wings have a cross-sectional diameter of between 2.3 mm and 4.2 mm in the first, proximal orientation.
[0015] In addition to or in lieu of the features of any of the example embodiments described above, the wings have a cross-sectional diameter of between 2.3 mm and 4.2 mm in the second, proximal orientation.
[0016] In another example, a method of deploying a biliary stent of any of the examples described above can include the steps of loading the stent in a first position onto a shaft of a delivery device of any of the examples described above; inserting a distal end of the shaft into a bile duct of a patient; positioning the stent within the patient; expanding the stent to a second position; and retracting the shaft, leaving the expanded stent in the bile duct.
[0017] In addition to or in lieu of the features of any of the example embodiments described above, the one or more wings at the distal end of the shaft are positioned in the first, proximal orientation during the inserting of the distal end of the shaft and the positioning of the stent. The retracting of the shaft includes moving the distal end of the shaft through the stent such that the wings transition from the first, proximal orientation to the second, distal orientation. The expanding of the stent is a result of the wings outwardly crushing the stent as the distal end of the shaft moves through the stent.
[0018] In addition to or in lieu of the features of any of the example embodiments described above, the method further includes the step of deploying a second stent loaded on the device.
[0019] These and other features and advantages of the present disclosure will be readily apparent to those skilled in the art from the following detailed description, wherein the scope of the claimed application is set forth in the appended claims. BRIEF DESCRIPTION OF DRAWINGS
[0020] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate various embodiments of the present disclosure and together with the description, serve to explain the principles of the present disclosure.
[0021] Figure 1 depicts a medical delivery device;
[0022] Figure 2A and 2B depicts a biliary stent in a contracted position;
[0023] Figure 3A and 3B depicts a biliary stent in an expanded position;
[0024] Figure 4 depicts a wing of the delivery device in a proximal orientation;
[0025] Figure 5 depicts the wing in a distal orientation;
[0026] Figures 6A to 6E depicts deployment of a biliary stent loaded on a shaft of a medical delivery device.
[0027] While the present disclosure can be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and will be described in detail herein. However, it should be understood that the intention is not to limit the application to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the present disclosure. DETAILED DESCRIPTION
[0028] The present disclosure will now be described with reference to an illustrative medical system that can be used in an endoscopic medical procedure. However, it should be noted that reference to this particular procedure is for convenience only and is not intended to limit the present disclosure. Those of ordinary skill in the art will recognize the underlying concepts of the disclosed devices and related methods of use can be used in any suitable procedure, whether medical or otherwise. The present disclosure can be understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals.
[0029] All numerical values herein are assumed to be qualified by the term “about,” whether or not explicitly indicated. The term “about” in the context of a numerical value generally means a range of values that a person of skill in the art would consider equivalent to the recited value (e.g., having the same function or result). In many cases, the term “about” can include numbers rounded to the nearest significant figure. Other uses of the term “about” (e.g., in contexts other than numerical values) are assumed to have their ordinary and customary definition as understood from the context of the specification and consistent therewith, unless otherwise indicated.
[0030] Numerical ranges recited herein include all numbers and include the endpoints (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5). Although some suitable dimensions, ranges and / or values are disclosed for various components, features and / or specifications, a person of ordinary skill in the art will understand that desired dimensions, ranges and / or values can deviate from those explicitly disclosed without departing from the scope of the disclosure.
[0031] As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense of “and / or” unless the content clearly dictates otherwise. It should be noted that for ease of understanding, certain features of the disclosure can be described in singular form even though these features can be plural or repeated in the disclosed embodiments. Each instance of a feature can include and / or be encompassed by the singularly disclosed content unless explicitly stated to the contrary. For simplicity and clarity, not every element or feature of the disclosure can be shown or discussed in every figure or discussed in the following detailed description. However, it will be understood that the following discussion applies equally to any and / or all elements having more than one part, unless explicitly stated to the contrary. In addition, for clarity and conciseness, not every instance of certain elements or features can be shown in every figure.
[0032] It should be noted that references to “one embodiment,” “some embodiments,” “other embodiments,” etc. in the specification mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. The appearances of the phrase “in one embodiment” in various places in the specification are not necessarily all referring to the same embodiment, though it can. Furthermore, the particular features, structures, or characteristics can be combined in any suitable manner in one or more embodiments. Additionally, the terms “first,” “second,” “third,” etc. are used herein to describe various elements or features and are not intended to be a permanent or absolute nomenclature.
[0033] For clarity, certain identifying numerical nomenclature (e.g., first, second, third, fourth, etc.) can be used throughout the description and / or claims to name and / or distinguish various described and / or claimed features. It will be understood that the numerical nomenclature is not intended to be limiting, and is merely illustrative. In some embodiments, for brevity and clarity, previously used numerical nomenclature can be changed and deviated from. That is, a feature identified as a “first” element can later be referred to as a “second” element, a “third” element, etc., or can be omitted altogether, and / or a different feature can be referred to as the “first” element. The meaning and / or designation in each instance will be apparent to the skilled practitioner.
[0034] The detailed description is intended to illustrate but not limit the present disclosure. Those skilled in the art will recognize that the various elements described can be arranged in various combinations and configurations, without departing from the scope of the disclosure. The detailed description illustrates example embodiments of the disclosure.
[0035] Figure 1 A biliary access device 100 according to some aspects of the present disclosure is shown. The device 100 includes a distal shaft 102 adapted for insertion into or near a patient’s biliary duct. The shaft 102 is sized and shaped to be fed over a guidewire via an auxiliary channel of an endoscope, the shaft 102 loaded with one or more biliary stents. A proximal handle 104 includes any necessary interface components for controlling the distal shaft 102, unloading the biliary stents, and expanding the stents during deployment as further described below. The handle 104 provides control over the shaft 102 during transport and deployment of the stents and final retraction and removal of the device 100.
[0036] A biliary stent 200 is shown in Figures 2A-3B The biliary stent 200 can have a first, collapsed form in which the plurality of leaflets 202 are biased inwardly concave between the pleats 204. In some implementations, the stent 200 can be formed of a resilient material such as a rigid thermoplastic that is able to maintain its shape. Those of ordinary skill in the art will recognize that any biocompatible material can be used, although the suitability of the material can depend on the nature of the procedure and placement of the stent. In Figure 3A and 3B In the expanded form, the leaflets 202 are biased outwardly convex between the pleats 204, greatly expanding the cross-sectional area of the stent 200. In this regard, the pleats 204 serve as hinge locations for the leaflets 202 to transition from the inwardly concave orientation to the outwardly convex orientation. Upon expansion after deployment as further described below, the stent 200 can have an effective radius greater than the channel through which it was transported upon deployment.
[0037] Biliary stent 200 is shown with five pleats and five symmetrical arc lengths of leaflets, although one of ordinary skill in the art will recognize that different numbers of leaflets are possible, including three, four, six, seven, eight, etc., and one or more leaflets can be longer than one or more other leaflets.
[0038] As shown in FIG. 2, expanded stent 200 forms an opening with the surrounding biliary tissue 302, which includes external passageways 304. These passageways 304 provide drainage along the exterior of stent 200, which can extend the life of stent 200 compared to the smooth, symmetrical sidewalls employed by conventional plastic tube stents. Figure 3B
[0039] The length and width of stent 200 can depend on its intended placement and / or the limitations of the access device. In some embodiments, the stent can have an axial length between 2 and 20 mm, and a cross-sectional diameter that can expand from 1 mm to 5 mm when collapsed to 2 mm to 10 mm when expanded.
[0040] Deployment of the biliary stent is aided by a shaft 400 with a wing 402, as shown in FIG. 3. Figure 4 and 5 Wing 402 can be transitioned between a first, proximal orientation position, as shown in FIG. 4, and a second, distal orientation position, as shown in FIG. 5. Wing 402 can be integrally formed with shaft 400, or can be attached to shaft 400 by mechanical means or by adhesive. Figure 4 Figure 5
[0041] Figures 6A to 6E Deployment of biliary stent 200 over shaft 400 is shown in FIG. 6. As shaft 400 is retracted through stent 200, wing 402 is transitioned from a proximal orientation to a distal orientation by contact with stent 200, with wing 402 passing through an intermediate orientation between the proximal and distal orientations. Wing 402 has sufficient resiliency and diameter that it does not collapse completely against the body of shaft 400, pushing stent 200 outward as they pass, opening stent 200 and re-orienting stent 200 from a collapsed state with leaflets in an inwardly concave orientation to an expanded state with leaflets in an outwardly convex orientation. Because wing 402 is flexible, and can tend to flatten due to the resistance provided by collapsed stent 200, multiple wings in series can be used in some embodiments to enhance the effectiveness of the leading wing, as the next wing in series acts as a barrier, thereby supporting the ability of the leading wing to overcome the resistance of the collapsed stent.
[0042] The cross-sectional diameter of the flaps 402 relates to the cross-sectional diameter of the stent 200 both before and after expansion, and can be the same or different when oriented in the first position or the second position. In some embodiments, each of the first and second flap positions can have a cross-sectional diameter between 2.3 mm and 4.2 mm.
[0043] In some embodiments, once the stent 200 is expanded and deployed, the flaps 402 can be biased to naturally return to a distal orientation against the shaft 400. In some embodiments, a mechanism such as a guidewire or thread can be provided to fold the flaps 402 against the shaft 400. Multiple stents 200 can be loaded on one shaft 400 for deployment during a single operation.
[0044] The stent 200 can be made of any biocompatible material, such as polyethylene plastic, that has sufficient flexibility and resiliency. The flaps 402 likewise can be made of any material that allows for proper transitioning between positions. In some embodiments, the flaps 402 can be made of a more rigid material than the stent 200 to ensure proper deployment interaction between the two.
[0045] It should be understood that the present disclosure is in many aspects only illustrative. Changes can be made in detail, particularly in matters of shape, size, and arrangement of steps, without exceeding the scope of the present disclosure. This can include, where appropriate, the use of an example embodiment for any other embodiment. The scope of the present application is defined by the language of the claims that follow, and no limitation arising therefrom is to be understood in the absence of a special contrary meaning in the specification.
Claims
1. A biliary stent, the biliary stent comprising a plurality of leaflets, the plurality of leaflets being radially alternating with a plurality of folds; in, Each of the plurality of leaflets has a first contraction position, the first contraction position being offset inward from the fold, such that the biliary stent has a first cross-sectional diameter. and Each of the plurality of leaflets has a second expansion position offset outward from the fold, such that the biliary stent has a second cross-sectional diameter that is larger than the first cross-sectional diameter.
2. The biliary stent according to claim 1, wherein the plurality of leaflets have the same length, such that the stent is symmetrical.
3. The biliary stent according to claim 1 or 2, wherein the stent is made of biocompatible plastic.
4. The biliary stent according to any one of claims 1 to 3, wherein when in the second expanded position, each of the leaflets forms a convex curve with an adjacent fold, such that once the biliary stent expands, the adjacent leaflets form a sidewall of the external passage of the stent.
5. The biliary stent according to any one of claims 1 to 4, wherein the stent in the first constricted position has a cross-sectional diameter between 1 mm and 5 mm.
6. The biliary stent according to any one of claims 1 to 5, wherein the stent in the second expansion position has a cross-sectional diameter between 2 mm and 10 mm.
7. The biliary stent according to any one of claims 1 to 6, wherein the stent has an axial length between 2 mm and 20 mm.
8. A biliary stent delivery device, comprising: A shaft, the dimensions of which are adapted for insertion into the patient's bile duct; as well as One or more flaps at the distal end of the shaft, wherein each flap switches between a first proximal orientation pointing towards the proximal end of the shaft and a second distal orientation pointing towards the distal end of the shaft.
9. The apparatus of claim 8, wherein the shaft is loaded with an expandable biliary stent for insertion into the bile duct, the expandable stent being positioned proximal to the one or more flaps such that, when the shaft retracts via the loaded stent, the flaps change from a first proximal orientation to a second distal orientation to outwardly compress the stent, causing the stent to expand.
10. The device according to claim 8 or 9, wherein the expandable biliary stent is a stent as described in any one of claims 1 to 7.
11. The device according to any one of claims 8 to 10, wherein the blade has a cross-sectional diameter between 2.3 mm and 4.2 mm in the first proximal orientation.
12. The device according to any one of claims 8 to 11, wherein the blade has a cross-sectional diameter between 2.3 mm and 4.2 mm in the second proximal orientation.
13. A method for deploying a biliary stent according to any one of claims 1 to 7, comprising the following steps: The bracket in the first position is loaded onto the shaft of the conveying device as described in any one of claims 8 to 12; Insert the distal end of the shaft into the patient's bile duct; Position the stent inside the patient's body; Expand the support to the second position; as well as The shaft is retracted, leaving the expanded stent in the bile duct.
14. The method of claim 13, wherein during insertion and positioning of the support at the distal end of the shaft, one or more flaps at the distal end of the shaft are positioned in a first proximal orientation; and Retracting the shaft includes moving the distal end of the shaft through the bracket, causing the flap to change from the first proximal orientation to the second distal orientation; Furthermore, the expansion of the support is a result of the flaps pressing the support outward as they move through the support at the distal end of the axis.
15. The method of claim 13 or 14, further comprising the step of deploying a second support mounted on the device.