Abstract: A stent graft delivery system includes a stent graft and a thermal stent graft cutter for shortening the stent graft to a desired length in vivo. The thermal stent graft cutter is coupled to at least one of a stent graft cover at a distal longitudinal end of a cover body thereof, and the inner lumen tip of an inner lumen. A safety system allows activation of the stent graft cutter only when the stent graft is suitably sandwiched between the inner lumen tip and the distal end of the stent graft cover to inhibit inadvertent activation of the cutter and provide for proper cutting of the stent graft.

Abstract: There is described a bioresorbable metal alloy which is particularly suitable for the formation of bioresorbable medical devices, for example stents. The metal alloy essentially comprises 3.2 to 4.8% by weight lithium, 0.5 to 2.0% by weight yttrium; and the balance being magnesium, in addition to any trace elements. The metal alloy can be drawn into a wire which can be shaped into a stent scaffold. The stent can be produced using one or more stent scaffolds together with one or more bioresorbable polymer connectors, for example formed from PLGA.

Abstract: A stent (scaffold) or other luminal prosthesis comprising circumferential structural elements which provide high strength after deployment and allows for scaffold to uncage, and/or allow for scaffold or luminal expansion thereafter. The circumferential scaffold is typically formed from non-degradable material and will be modified to expand and/or uncage after deployment.

Abstract: The invention described herein relates to telescoping stents. The embodiments described herein allow for adequate securement to, accommodation for movement by, and prevention of injury of tubular organs or hollow areas of the body. Certain embodiments relate to telescoping stents with loop interlocking mechanisms. Further embodiments relate to telescoping stents with ball-in-groove interlocking mechanisms.

Abstract: The present disclosure relates to a medical device, methods of making a medical device, and methods of delivering medical device. Particularly, aspects of the present disclosure are directed to a medical device having a self-expanding stent and a thin-film neural interface. The stent comprises a plurality of struts having a substantially elliptical or circular geometry arranged in series from a proximal end to a distal end of the stent, and a thin-film neural interface attached to the stent. Each strut of the self-expanding stent comprises a top portion and a base portion integrally connected with the top portion at a first connection point and a second connection point such that the top portion moves relative to the base portion. The self-expanding stent provides a retracted configuration to protect the thin-film neural interface during delivery, and an expanded configuration to deploy the thin-film neural interface.

Abstract: The invention relates to a stent and a system for putting in place a stent. Said stent is used especially for splinting a vein and consists of a braided, tubular supporting member (2) that has a minimum length of 60 mm. The supporting member is braided from one or more wires in such a way that portions of the wire or wires, resp., delimit rhombuses. The disclosed stent is characterized in that in the unloaded state of the stent, the longitudinal size of most of the rhombuses (7) in the longitudinal direction (15) of the stent (1) is not shorter than the transversal size of the rhombuses.

Abstract: A flow diverter device is used to redirect the blood flow inside the cerebral blood vessels and for the reduction of blood flow to the aneurysm, hence preventing the chance of aneurysm rupture as well as promoting the healing of the aneurysm. The novel design of the device, using a set of thicker wires, provides high kink resistance and radial strength. Two patterns of inter-braiding the thicker set of wires with the finer braid are disclosed, one having a checker-board and the other a ring structure. Both patterns are highly kink resistant with the checker-board design providing minimal loss in flexibility, whereas the ring design provides greater radial strength. The device could be made of super elastic materials like Nitinol wires with the thicker set being radio opaque. The device is highly kink resistant and sufficiently flexible for use in vasculature with complex bends.

Abstract: A tubular, folding flow diverter is provided. The flow diverter includes a plurality of sections, including a first section, a second section, and a third section. The flow diverter is shapeable to an elongated cylindrical shape and is movable to an implanted configuration. In the implanted configuration, the second section and at least a portion of the first and third sections overlap to form a three-layer shape. This three-layer shape can be positioned proximate an aneurysm neck when implanted in a patient. The overall porosity of the implant can be higher than legacy implants, because the overlapping portion of the three sections can decrease the porosity proximate the aneurysm neck.

Abstract: A bidirectional twistable stent is disclosed. The stent comprises a cylinder-shaped stent body having a plurality of axially arranged rows of struts encircling a central lumen and a plurality of flex connectors that connect at least two adjacent rows of struts in such a manner that allows the stent to be twisted clockwise or counter clockwise without causing deformation of any struts in the stent body. Also disclosed are the method of making the stent, method of using the stent, and a kit containing the stent.

Abstract: One embodiment of the invention incudes a single cylinder zigzag strut Z stent cylinder fixedly joined to a braided stent such that a portion of the joined Z stent cylinder extends beyond the termination end of the braided wire stent. The Z stent cylinder can have a larger in diameter than the braided stent when expanded.

Abstract: A stent suitable for deployment in a blood vessel to support at least part of an internal wall of the blood vessel comprises a plurality of longitudinally spaced-apart annular elements, and a plurality of connecting elements to connect adjacent annular elements. Each connecting element is circumferentially offset from the previous connecting element. Upon application of a load to the stent, the stent moves from an unloaded configuration to a loaded configuration. In the unloaded configuration the longitudinal axis of the stent is straight, and the stent is cylindrically shaped. In the loaded configuration the longitudinal axis of the stent is curved in three-dimensional space, and the stent is helically shaped.

Abstract: Some embodiments provide a system to facilitate transaction processing associated with an industrial asset supply chain having a first entity and a second entity. A first entity computer processor may retrieve, from a first entity database, information associated with pre-delivery data about the industrial asset. The first entity computer processor may then record pre-delivery data about the industrial asset via a secure, distributed transaction ledger. A second entity computer processor may retrieve, from a second entity database, information associated with a post-delivery event involving the industrial asset. The second entity computer processor may then record post-delivery event data about the industrial asset via a secure, distributed transaction ledger. The post-delivery event data might indicate, for example, that the industrial asset has been delivered, has been installed, is working properly, has been used, etc.

Abstract: The invention includes an expandable stent having a tubular shape when expanded, the shape including a portion t where the stent radius grows with stent length so that the growth in the portion is constant conductance growth or near-constant conductance growth. The invention includes sheaths that will encase the stent to restrict the growth of the stent to the desired expanded shape. The invention also includes expandable stent balloons that expand the stent to the desired shape configuration with constant or near constant conductance portion. The balloons can include a similar sheath or sleeve to restrict the balloon's growth to the desired shape. The stent radius growth can be piecewise, and is not necessarily 4th order growth, but can be such that rn/l is a constant in the portion, where n>4.

Abstract: Systems and methods for treating diseased bodily lumens involving branched lumen deployment sites include a main graft or stent-graft deployable in a main artery and a vent device or stent-graft deployable in a branch artery to maintain blood flow through the main artery and from the main artery to the branch artery. Systems and methods for treating diseased bodily lumens involving branched lumen deployment sites may also include a main graft or stent-graft deployable in the main artery, a chimney graft or stent-graft deployable in both branch artery and the main artery to the branch artery and a gutter-sealing device associated with the chimney graft to prevent flow of blood among the chimney graft, the main graft and a wall of the main artery.

Abstract: A virtual stent placement apparatus, a virtual stent placement method, and a virtual stent placement program for preventing a stent from blocking a branch of a blood vessel in a case in which the stent is virtually placed in the blood vessel extracted from a medical image are disclosed.

Abstract: A constraining structure for use with a balloon catheter can include multiple longitudinal struts and multiple, sinusoidal shaped radial rings. The constraining structure can expand to form a pattern of channels including substantially square windows. The constraining structure can modify, restrict, and control a shape and/or size of the balloon when inflated. Inflating the balloon catheter within the constraining structure can provide nonuniform pressure on a vessel wall adjacent the balloon.

Abstract: An expandable stent for implantation in a body lumen, such as an artery, is disclosed. The stent consists of a plurality of radially expandable cylindrical rings generally aligned on a common longitudinal stent axis and interconnected by one or more interconnecting links placed so that the stent is flexible in the longitudinal direction. The link pattern is optimized to enhance longitudinal flexibility and high longitudinal strength compression of the stent.

Abstract: Medical stent designs are disclosed. An example stent includes a tubular scaffold having a proximal end and a distal end. The tubular scaffold includes a first filament extending between the proximal end and the distal end, the first filament including a first biodegradable region positioned adjacent to a second biodegradable region. Further, the first biodegradable region includes a first biodegradable material, the first biodegradable material having a first rate of degradation. The second biodegradable region includes a second biodegradable material, the second biodegradable material having a second rate of degradation, wherein the first rate of degradation is different from the second rate of degradation.

Abstract: Apparatus and methods are described including a blood pump that includes an impeller configured to pump blood through a subject's body, and a frame disposed around the impeller. The frame defines struts having a structure that is such that, as the frame transitions from a proximal end of the frame toward a center of the frame, the struts pass through junctions, at which the two struts branch from a single strut, in a Y-shape. The structure of the struts of the frame is configured such that, in response to a distal end of a delivery catheter and the frame being moved into overlapping positions with respect to each other, the frame assumes a radially-constrained configuration by becoming axially elongated, and the frame causes the impeller to assume a radially-constrained configuration by becoming axially elongated. Other applications are also described.

Abstract: Prostheses and methods of making the same are provided. The prosthesis has an internal branch configuration. A trough or branch opening is at least partially defined by a trough wall extending into a main lumen from a sidewall of the prosthesis. The internal branch extends from the trough within the main lumen towards one of the outflow end of the graft body in a helical, retrograde arrangement. Other arrangements are described. The prosthesis may include a scalloped fenestration having a width larger than the trough. The trough may be positioned along a tapered region of the prosthesis. The trough and internal branch may be made from the same graft material. The trough and internal branch, in addition to the main graft body, may be made from the same graft material.

Abstract: A bifurcated implant delivery system is provided for deploying a bifurcated expandable implant in a patient lumen. A shaft has at least two shaft proximal openings. A shaft distal end has at least two shaft branches longitudinally extending from a shaft body distal end. Each of the shaft branches has a shaft open tip. The shaft has at least one shaft lumen that longitudinally extends between a respective shaft proximal opening and at least one respective shaft open tip. A reinforcing element longitudinally extends from the shaft body distal end. An outer sheath has an outer sheath proximal opening and at least one outer sheath open tip. An outer sheath lumen longitudinally extends between the outer sheath proximal opening and the at least one outer sheath open tip. The outer sheath lumen is for selectively holding at least a portion of the shaft and a bifurcated expandable implant therein.

Abstract: Prosthetic devices and frames for implantation at a cardiac valve annulus are provided that include an annular frame (having an inflow end and an outflow end) and a plurality of axial frame members that bridge two circumferentially extending rows of angled struts. The axial frame members can include a plurality of axially extending leaflet attachment members and a plurality of axial struts in a 1:1 ratio. Along each of the two rows, the frame can have at least three angled struts between adjacent axial frame members.

Abstract: A stent includes a fluid-permeable stent body having longitudinally separated proximal and distal stent ends. The stent body has inner and outer stent body surfaces. The stent body defines at least one longitudinally extending primary lumen and at least two longitudinally extending secondary lumens laterally spaced from one another with at least a portion of the primary lumen interposed laterally therebetween. The secondary and primary lumens all are at least partially fluid-permeable between the inner and outer stent body surfaces. At least one fluid-impermeable and longitudinally extending berm is located directly laterally adjacent a corresponding secondary lumen. The berm prevents fluid flow laterally between at least a portion of the corresponding secondary lumen and a space laterally opposite the secondary lumen beyond the berm. A method of using the stent in at least partially extending a superior landing zone of an abdominal aortic aneurysm is also described.

Abstract: A visceral double-barreled main body stent graft and methods for its use, the stent graft comprises, a main body stent graft having distal and proximal ends, the main body stent graft's length ranges from about 100-120 mm and diameter at the proximal end ranges from about 30-45 mm, first and second lumens defined at the main body stent graft's distal end, the first lumen's diameter ranges from about 18-20 mm, the second lumen's diameter ranges from about 16-18 mm, the first and second lumens have about the same length from about 50-70 mm, the first lumen is secured to the second lumen along a shared length, and the main body stent graft defines a tubular wall that is contiguous with the first and second lumens such that any fluid entering the main body must exit through one of the first or second lumens.

Abstract: A stent comprises a first longitudinally extended cylindrical-shaped member. The first member comprises a plurality of first longitudinal struts and an array of first radial struts extending between the first longitudinal struts. The stent further comprises an overlapping region to form a dense mesh.

Abstract: A bio-absorbable implant is configured to bear radially outwardly against a Eustachian tube of a patient. The implant includes a proximal portion and a distal portion. The proximal portion includes an array of dilating bodies and a tether assembly. The dilating bodies are formed of a bio-absorbable material and are dimensioned to bear radially outwardly against the Eustachian tube of the patient. The tether assembly connects adjacent dilating bodies of the array of dilating bodies. The tether assembly is configured to allow restricted movement of the array of dilating bodies to thereby change the longitudinal profile of the proximal portion. The distal portion includes an anchor assembly that is configured to secure the bio-absorbable implant in the Eustachian tube of the patient.

Abstract: In accordance with the present invention, there is provided a stent for insertion into a vessel of a patient. The stent is a tubular member having front and back open ends and a longitudinal axis extending there between. The tubular member has a first smaller diameter for insertion into a patient and navigation through the vessels, and a second larger diameter for deployment into the target area of a vessel. The tubular member is made from a plurality of adjacent hoops extending between the front and back ends. The hoops include a plurality of longitudinal struts and a plurality of loops connecting adjacent struts. The stent further includes a plurality of bridges having loop to bridge connections which connect adjacent hoops to one another. The bridge to loop connection points are separated angularly with respect to the longitudinal axis. The bridges have one end attached to a loop, another end attached to a loop on an adjacent hoop.

Abstract: In part, the disclosure relates to systems and methods to assess stent/scaffold expansion in a vessel on an expedited time scale after stent/scaffold placement and expansion. In one embodiment, the method generates a first representation of a stented segment of the blood vessel indicative of a level of stent expansion; determines using the detected stent struts, a first end of the stent and a second end of the stent; and generate a second representation of the segment of the blood vessel by interpolating a lumen profile using an offset distance from the first end and the second end.

Abstract: A sphincter assist device includes a plurality of interconnected and adjacent links which define a ring. Each link includes a body section and a latch cam. The body section includes a first set of side beams and a first set of snap arms. The latch cam includes a post extending from the body section and a cam disposed at an end portion of the post. The cam is engagable with the first set of snap arms of an adjacent link. Translation of the cam displaces the first set of snap arms and the first set of side beams to transition the sphincter assist device between open and closed configurations. The first set of snap arms, in combination with the first set of side beams, exert a positive non-linear force profile on the cam, thus defining a non-linear force profile of the sphincter assist device between the open and closed configurations.

Abstract: Provided herein is a system including, in some embodiments, a stent and a catheter. The stent includes a number of filaments arranged to form a tubular body of the stent, a number of microcells forming each filament of the number of filaments, and a port in an end portion of the stent. Each microcell includes a moveable microsurface. The port of the stent may be configured to accept power and control signals for moving the microsurfaces. The catheter may include a cable configured to connect with the port of the stent and provide the power and the control signals for moving the microsurfaces. Moving the microsurfaces may include matching a shape of an anatomical vessel to maintain patency thereof while mitigating stress on the anatomical vessel.

Abstract: Disclosed herein is a hybrid stent having a balloon-expandable portion joined to a self-expanding portion. The hybrid stent is capable of withstanding the forces applied by delivery. Delivery systems for deploying a hybrid stent are described, as are methods of using such delivery systems.

Abstract: A universal implantable integrated circuit medical device platform having integral and monolithic circuit traces. The platform allows for implanting into a mammalian body single and multi-functional interface devices for sensing, monitoring stimulating and/or modulating physiological conditions within the body. Microelectronic circuitry may be integrated onto the platform or may be joined as modular components to the platform.

Abstract: An actuator system is provided having a fluidic body member having a surface configured to be deformable in response to a pressure differential. One or more auxetic elements are disposed on and engage the surface of the fluidic body member in the form of a network of beam elements. The auxetic element has a negative Poisson's ratio resulting in kinematics such that upon application of the internal fluid pressure, the surface of the fluidic body member is caused to have specific kinematics enabling planar and 3D motions. In some embodiments, the plurality of non-auxetic elements cooperate with a plurality of auxetic elements.

Abstract: An interventional medical device delivery system comprises a loader provided with a loading tube, a delivery sheath, a dilator, a pushing component, and a hemostasis valve. The loading tube or the delivery sheath is provided with a position-limiting locking connector. An appropriate-rotation control mechanism for controlling a tightening degree between a distal end of the loading tube and a proximal end of the delivery sheath is disposed outside the loading tube or the delivery sheath. The proximal end of the delivery sheath and the distal end of the loading tube engage with each other in a sealed manner, and are threadingly fixed to each other by means of the position-limiting locking connector. The appropriate-rotation control mechanism rotates in one direction to appropriately tighten a thread-connection, and rotates in the opposite direction to release the thread-connection. The interventional medical device conveying system of the invention automatically determines a tightening degree.

Abstract: An absorbable stent includes an absorbable matrix. The matrix includes a number of wave-shaped rings connected by connection units and arranged in an axial direction. The wave-shaped ring includes a number of waves arranged in a circumferential direction. A peak, a valley and a support connecting the peak and the valley form the wave. Two adjacent wave-shaped rings and the connection unit form a closed side supporting unit. The matrix has a volume of [4, 40] ?m per unit blood vessel area. The absorbable stent has sufficient radial supporting strength for clinical applications. Moreover, the volume of the matrix per unit blood vessel area is less than volumes of existing stents. When the absorbable stent and existing stents are made of the same material, the absorbable stent has a shorter degradation and absorption cycle.

Abstract: The present invention relates to adurable and multifunctional superhydrophobic coating composition and water based fabrication method of producing the durable and multifunctional superhydrophobic coating composition via chemical modification and functionalization of hydrophilic material by silanes under room temperature without any organic solvents. Synthesis of chemically modified cellulose nanofibers or clay in water forms excellent water repelling thin films upon coating over various substrates. The super hydrophobic materials are used as additive for paints, pigments, paper, varnish and, textile and used for various industrial applications such as construction of buildings and other super structures.

Abstract: A multi-element, bioresorbable, vascular stent may be used to maintain or enhance patency of a blood vessel. The stent may be used in peripheral blood vessels, which may be long and/or tortuous. By using multiple, separate stent elements that are balloon expandable, the multi-element stent may be stronger than a traditional self-expanding stent but may also be more flexible, due to its multiple-element configuration, than a traditional balloon-expandable stent. Thus, the multi-element, bioresorbable, vascular stent described herein may be particularly advantageous for treating long lesions in tortuous peripheral blood vessels.

Abstract: A surgical heart valve includes a non-collapsible frame having features that enable the frame to expand from an initial condition having a first diameter to an expanded condition having a second diameter larger than the first diameter after the valve has been implanted within a patient. The frame may include members that prevent the unintended expansion of the frame, such as during implantation, and members that prevent the over-expansion of the frame. The surgical heart valve further includes a valve assembly connected to the frame and including a plurality of leaflets.

Abstract: An endovascular stent graft for treatment of a blood vessel is provided. The stent is configured to be inserted into the blood vessel while in a radially-contracted configuration, and may be opened into a radially-expanded configuration once properly located within the blood vessel. The stent graft includes a main body having a proximal end and a distal end. The distal end of the main body is connected to a first leg and a second leg. A first plurality of stitching extends along a first seam path and connects the main body to the first leg, while a second plurality of stitching extends along a second seam path and connects the main body to the second leg. At least one of the first or second seam axes can be offset, in that the seam path does not extent perpendicular to a longitudinal axis of the stent graft.

Abstract: An auxetic bi-stable structure that comprises an auxetic curved shell movable between a first and a second stable position, and a rigid element. At least part of the surface of the auxetic curved shell is joined to the rigid element such that the curved shell is movable with respect to the rigid element between the first and second stable positions.

Abstract: An intraluminal device and method of fixation of an intraluminal device at a recipient having an esophagus, a stomach with a cardiac portion and a GE junction between the esophagus and the cardiac portion of the stomach includes deploying the intraluminal device to the recipient. The intraluminal device has a wall defining a cardiac member that is configured to the size and shape of the cardiac portion of the stomach and deployed to the cardiac portion of the stomach and an esophageal member that is configured to the size and shape of a portion of the esophagus and deployed to the esophagus. The intraluminal device having a connector connected with the esophageal portion and cardiac portion and deployed to the GE junction. The wall is fixed to the recipient to resist distal migration of the wall. The fixing includes the wall having a wall characteristic that is configured to facilitate tissue ingrowth.

Abstract: An endograft is provided for a blood vessel having a branch extending from said blood vessel, including a body having a wall defining a lumen and an exterior surface. The endograft body includes a first portion defining or being made to define a non-circular cross-sectional dimension, and a second portion defining a circular cross-sectional dimension. Modular systems including the endograft and methods for creating endografts according to the disclosure are described also.

Abstract: Systems, devices and methods for occluding the left atrial appendage (LAA). The device excludes the LAA from blood flow. The implantable device is delivered via transcatheter delivery into the LAA and secured within the LAA. The implant comprises an expandable and compliant frame and an expandable and conformable tubular foam body. A delivery and tether retraction system includes a handle for controlling a pusher and tether. The pusher may be moved a distance away from the implant without changing the orientation of the implant, while the tether is still attached to the implant. Severing the tether and proximally retracting a control on the hand piece by a distance causes the severed end to advance distally by at least about twice that distance. A loader includes a conical portion with guides and a reservoir for submerging the foam prior to loading and delivery.

Abstract: The techniques of this disclosure generally relate to a modular stent device that is deployed into the ascending aorta via femoral access. The modular stent device is a base or anchor component to which additional modular stent devices can be attached to exclude diseased areas of the aorta while at the same time allowing perfusion of the brachiocephalic artery, the left common carotid artery, and/or the left subclavian artery.

Abstract: A device for capturing and removing an obstruction in a bodily duct of a patient. The device includes a cylindrical body having a circumference and a longitudinal axis. According to some implementations the cylindrical body is comprised of a plurality of closed cell structures arranged in diagonal rows around the longitudinal axis. At least some of closed cell structures have substantially the same shape and size. According to some implementations at least some of the closed cell structures of substantially the same shape and size occupy a same circumferential location in the cylindrical body and are longitudinally separated from one another by no less than two, three, four or more diagonal rows of closed cell structures. According to other implementations the closed cell structures include diagonally extending struts having at least a curve portion and a straight portion.

Abstract: A stent for use in hollow tubular organs, comprising a continuous tubular or cylindrical inner cavity which is delimited by a wall. The wall is formed in a tubular or cylindrical manner about an axis which runs in a longitudinal direction and has a structure which surrounds the wall. The structure is made of elements, and the elements are made of loops which are arranged about the longitudinal axis in the radial direction. The elements are rigidly connected via connection points such that a tubular or cylindrical single-piece wall structure is produced, and the stent has acute angles in the region of the connection points.

Abstract: Devices that can be delivered into a vascular system to divert flow are disclosed herein. According to some embodiments, devices are provided for treating aneurysms b diverting flow. An expandable device can comprise, for example, a plurality of strut regions and a plurality of bridge regions. Each of the strut regions may extend circumferentially about the expandable device and include a plurality of struts. Each of the plurality of bridge regions may be attached to and extend between two of the strut regions and comprise a plurality first bridges and second bridges that intersect one another and are movable relative to one another at their intersections.

Abstract: The present invention relates a vascular prosthesis for a blood vessel of a patient, which has the following: a hollow-cylindrical main body with a main lumen extending therein, an also a multiplicity of stent rings, which are not connected to one another, are arranged spaced apart one behind the other in the longitudinal direction of the vascular prosthesis and running around in a meandering formation. The vascular prosthesis also has four side branches, which extend distally into the main lumen from fenestrations in the prosthesis material lying between the stent rings.

Abstract: A multi-lumen stent assembly (100) for deployment in a bifurcated vessel. This assembly is made of a self-expandable main body component (200) and two lumen extensions (300), able to be inserted into one of the lumens of a double-barrelled portion (208) of the main body component (200). The main body component (200) has a proximal end (201) configured to be placed toward the heart and a distal end (202). The main body component (200) has a main body portion (203), a concaved portion (206), and a transition portion (205). The main body portion (203) has a cylindrical lumen (204) of constant diameter. The concaved portion (206) has a double-barrelled portion (208) having two lumens (211). A cross-section of the transition portion (205) evolving from a circular shape to an elliptical shape towards the transition portion (205), a larger diameter of this shape being in a central plane (CP).

Abstract: A ball-type anti-reflux biliary stent, including a meshed body, a cup and a ball. The cup and the ball are respectively provided at two ends of the meshed body. Inner diameters of the cup and the ball is larger than that of the meshed body. The meshed body includes a plurality of sections, and two adjacent sections are connected by a flexible wire. The cup of the stent is a cylinder open outwards, and the opening of the ball is connected to a tube having a substantially elliptical cross section. Therefore, a displacement of the stent is prevented for an accurate fixation of the stent. Moreover, the intestinal juice is prevented from flowing back into the biliary tract, avoiding infectious diseases.