METHODS FOR STENT DELIVERY AND POSITIONING FOR TRANSLUMINAL APPLICATION

Methods, apparatuses, and systems are described for stent delivery and positioning for transluminal application. The method may include positioning the stent in an undeployed configuration through an access site in a wall of a first body lumen. In some cases, the method may include retracting an outer sheath proximally and past an anchoring component disposed at a distal portion of an inner tubular member based on positioning the stent. A distal portion of the stent may be disposed between the anchoring component and the outer sheath while the stent is in the undeployed configuration. The method may further include deploying the distal portion of the stent from the outer sheath and within the first body lumen and expanding a proximal portion of the stent from within the outer sheath such that upon fully exiting the outer sheath, the proximal portion expands to a deployed configuration within a second body lumen.

BACKGROUND

Diseases and disorders of the gallbladder, pancreas, and bile ducts (i.e., pancreaticobiliary system) are associated with significant morbidity, mortality, and impaired quality of life. Obstructions, tumors, injuries, leakages, inflammation, infection, and lesions can occur in these structures, which can eventually lead to conditions such as biliary colic, cholecystitis, choledocholithiasis, cholelithiasis, pancreatitis, pancreatic duct stone formations, and chronic abdominal pain. Diseases of the pancreaticobiliary system may also be associated with nutritional disorders, such as malnutrition, obesity, and high cholesterol.

To treat a biliary obstruction, a clinician may perform a stent delivery procedure to place a stent across the body lumen to bypass the obstruction. In general, a stent delivery procedure may include placing an endoscope into the gastrointestinal tract and accessing the bile duct with a catheter. A guidewire may then be deployed through the catheter and into the bile duct. Once the guidewire is in place, a stent or other treatment device may be advanced over the guidewire into the bile duct. After the stent is placed in the bile duct, the clinician may withdraw the stent delivery system.

SUMMARY

The described features generally relate to improved methods, systems, and devices for stent delivery and positioning for transluminal application. The method may include delivering the stent in an undeployed configuration through an access site of a body lumen and retracting an outer sheath proximally and past an anchoring component disposed at a distal portion of an inner tubular member. A distal portion of the stent may be disposed coaxially along the anchoring component such that the distal portion of the stent is disposed between the anchoring component and the outer sheath. In some cases, the distal portion of the stent may expand within the body lumen by retracting the outer sheath past the anchoring component. The proximal portion of the stent may expand from within the outer sheath such that the stent may then fully expand within a second body lumen.

A method for delivering a stent is described. The method may include positioning the stent in an undeployed configuration through an access site in a wall of a first body lumen, retracting an outer sheath proximally and past an anchoring component disposed at a distal portion of an inner tubular member based at least in part on positioning the stent, wherein a distal portion of the stent is disposed coaxially along the anchoring component such that the distal portion of the stent is disposed between the anchoring component and the outer sheath while the stent is in the undeployed configuration, deploying the distal portion of the stent from the outer sheath into a deployed configuration within the first body lumen based at least in part on retracting the outer sheath past the anchoring component, and expanding a proximal portion of the stent from within the outer sheath such that upon fully exiting the outer sheath, the proximal portion expands to a deployed configuration within a second body lumen.

The method may further include retaining the distal portion of the stent in place along the inner tubular member as the outer sheath is retracted past the anchoring component based at least in part on the distal portion of the stent being disposed between the anchoring component and the outer sheath. In some cases, deploying the distal portion of the stent may further include releasing the distal portion of the stent from the anchoring component and into the deployed configuration based at least in part on retracting the outer sheath past the anchoring component. In some cases, deploying the distal portion of the stent may further include expanding the distal portion of the stent from the undeployed configuration to the deployed configuration while the outer sheath is retracted based at least in part on a pressure being released between the anchoring component and the outer sheath as the outer sheath is retracted.

The method may further include compressing the distal portion of the stent in the undeployed configuration between the anchoring component and the outer sheath, wherein deploying the distal portion of the stent is based at least in part on compressing the distal portion of the stent. In some cases, deploying the distal portion of the stent may further include expanding a flared portion of the stent within the first body lumen based at least in part on retracting the outer sheath. The method may further include anchoring the flared portion of the stent within the first body lumen such that the distal portion of the stent remains in a fixed position.

The method may further include compressing the distal portion of the stent against the wall of the first body lumen based at least in part on deploying the distal portion of the stent from the outer sheath. The method may further include maintaining the anchoring component and the inner tubular member in a stationary position while retracting the outer sheath. The method may further include expanding an entire portion of the stent such that at least a portion of the stent extends through the first body lumen and into the second body lumen. The method may further include pulling the inner tubular member from a proximal end of the inner tubular member and removing the anchoring component and the inner tubular member from the first body lumen and the second body lumen after the stent fully deploys.

In some cases, the inner tubular member comprises a proximal marker around the inner tubular member and positioned such that a proximal end of the stent abuts against the proximal marker while the stent is in the undeployed configuration, and the method may further include aligning a distal end of the proximal marker with a wall of the second body lumen, maintaining the proximal marker in a stationary position while retracting the outer sheath based at least in part on aligning the distal end of the proximal marker, and withdrawing the outer sheath past the distal end of the proximal marker based at least in part on maintaining the proximal marker in the stationary position, wherein expanding the proximal portion of the stent is based at least in part on withdrawing the outer sheath past the proximal marker.

The method may further include withdrawing the outer sheath until the proximal portion of the stent fully exits the outer sheath based at least in part on deploying the distal portion of the stent. The method may further include advancing a stent delivery apparatus through the first body lumen and the second body lumen before delivering the stent and removing the stent delivery apparatus through the first body lumen and the second body lumen after expanding the stent. In some cases, the stent delivery apparatus comprises an electrocautery tip coupled with a distal end of the inner tubular member, and the method may include applying energy, via the electrocautery tip, to the wall of the first body lumen and accessing, via the access site, the first body lumen based at least in part on applying the energy to the wall of the first body lumen, wherein positioning the stent is based at least in part on accessing the first body lumen.

In some cases, the stent delivery apparatus comprises an isolation sheath, wherein the isolation sheath is disposed around the outer sheath, and wherein retracting the outer sheath may include maintaining the isolation sheath in a stationary position while retracting the outer sheath and withdrawing the outer sheath into the isolation sheath based at least in part on positioning the stent. In some cases, the stent delivery apparatus comprises a guidewire, wherein the guidewire is slidably disposed within the inner tubular member, and wherein the method further include advancing the guidewire through the access site before positioning the stent.

Certain embodiments of the present disclosure may include some, all, or none of the above advantages or features. One or more other technical advantages or features may be readily apparent to those skilled in the art from the figures, descriptions, and claims included herein. Moreover, while specific advantages or features have been enumerated above, various embodiments may include all, some, or none of the enumerated advantages or features.

DETAILED DESCRIPTION

The present disclosure is generally directed to delivering a stent and positioning the stent for transluminal application. In certain procedures described herein, to place a stent within a body lumen, the luminal wall is pierced, and a stent delivery system is advanced through the hole (i.e., access site or access hole) and positioned at the target site to bypass an obstruction. The stent is then deployed from the stent delivery system, and the stent delivery system is withdrawn back out of the lumen through the same hole. If the stent is not accurately and precisely deployed, the stent may be unable to form a bridge between two body lumens and therefore, may be unable to bypass the obstruction. For example, if the distal portion of the stent is deployed short of (e.g., below) the access hole, the stent may be unable to connect the two body lumens and unable to form an alternate route to bypass the obstruction. In some cases, inaccurate deployment may result in fluid from the lumen leaking out into the surrounding tissue and organs, which may potentially cause serious discomfort or other medical complications.

In some cases, the stent may be positioned through an access site in a wall of a first body lumen after using a distal cutting element to create the access site. The stent may be in an undeployed configuration such that the stent is housed within the outer sheath. The system for delivering the stent may include an inner tubular member that is configured to advance through an access site in a wall of the body lumen. The stent may be disposed coaxially onto the inner tubular member. The outer sheath may be disposed coaxially along at least a portion of the inner tubular member such that the stent is disposed between the inner tubular member and the outer sheath while the stent is in an undeployed configuration.

The system for delivering the stent may further include an anchoring component disposed at a distal portion of the inner tubular member. In some cases, a distal portion of the stent may be disposed coaxially along the anchoring component such that the distal portion of the stent is disposed between the anchoring component and the outer sheath while the stent is in the undeployed configuration. The anchoring component may be configured to retain a distal portion of the stent in place along the inner tubular member as the outer sheath is retracted proximally to deploy the stent. For example, the outer sheath may be retracted proximally and past the anchoring component disposed at a distal portion of an inner tubular member while the anchoring component and the inner tubular memory remain stationary.

Upon retraction of the outer sheath, the stent releases from the anchoring component and expands into a deployed configuration within the body lumen. For example, the distal portion of the stent may deploy from the outer sheath into a deployed configuration within the first body lumen based on retracting the outer sheath past the anchoring component. In such cases, the distal portion of the stent may accurately and precisely deploy in the first body lumen, thereby enabling the stent to be able to form a bridge between two body lumens and bypass the obstruction. For example, the distal portion of the stent may deploy in the first body lumen and anchor itself within the first body lumen.

The stent may be an example of a non-foreshortening stent. For example, the stent may include a helical wrapping pattern that may be configured to reduce a foreshortening of the stent body upon deployment from the undeployed configuration to the deployed configuration to less than ten percent of a length of the stent body in the undeployed configuration. In such cases, the stent may remain in place during retraction of the outer sheath and deployment of the distal portion as the outer sheath continues to be retracted proximally. The non-foreshortening stent may enable accurate deployment by positioning the stent within the body lumen and maintaining the position of the stent within the body lumen before and after deploying the stent.

The system for delivering the stent may further include a proximal marker disposed around the inner tubular member and positioned such that a proximal end of the stent abuts against the proximal marker while the stent is in the undeployed configuration. The proximal marker may be configured to indicate a location of the proximal end of the stent within the system endoscopically and/or fluoroscopically. For example, a distal end of the marker may be aligned with a wall of the second body lumen to ensure that the proximal portion of the stent precisely deploys within the second body lumen and allows the stent to bridge between two body lumens upon expansion. The outer sheath may be withdrawn past the distal end of the marker to expand the proximal portion of the stent. In such cases, the proximal portion of the stent may expand from within the outer sheath such that upon fully exiting the outer sheath, the proximal portion expands to a deployed configuration within the second body lumen. The deployed configuration may be an example of the stent fully exiting the outer sheath and expanding between the first body lumen and the second body lumen, thereby providing an alternative route to bypass the obstruction.

In some cases, the stent may include a stent body having a first diameter and a first length in a deployed configuration. The stent may include a helical wrapping pattern that is at least partially covered with a material. In some cases, the stent may include at least two anchoring members coupled with a distal portion and a proximal portion, respectively, of the stent body. For example, the stent may include a first anchoring member coupled with a distal portion of the stent body and configured to increase a diameter of the distal portion of the stent body to a second diameter greater than the first diameter. The stent may further include a second anchoring member coupled with a proximal portion of the stent body and configured to increase a diameter of the proximal portion of the stent body to the second diameter greater than the first diameter. Each of the anchoring members may be configured to anchor the distal and proximal portions of the stent within the respective body lumens such that the stent remains in a fixed position.

Embodiments of the present disclosure are now described in detail with reference to the drawings. As used herein, the term “clinician” refers to a doctor, surgeon, nurse, or any other car provider and may include support personnel. The term “proximal” will refer to the portion of the device or component thereof that is closer to the clinician and the term ‘distal” will refer to the portion of the device or component thereof that is farther from the clinician.

FIG.1illustrates a system100for providing access to a body lumen and delivering a stent in accordance with aspects of the present disclosure. The system100generally includes an outer sheath105, an isolation sheath110, a proximal marker115, an anchoring component120, an electrocautery tip125, an inner tubular member130, a stent150, and a guidewire145. The system100can be provided as individual components, selectively combined components, or all together as a kit of components.

During a luminal access and stent150delivery procedure, the electrocautery tip125may access the target body lumen by piercing a wall of the body lumen, for example, to deliver a stent150. In general, a stent150is a frame or scaffolding structure sized for placement within a body lumen and configured to provide structural support to the inner surface of the body lumen. A stent150may be used to restore patency across narrowed or blocked areas within the body lumen due to inflammation, tumors, plaque buildup, or any other obstructive feature. Although references to the pancreaticobiliary system are provided herein, it should be appreciated that the stents described herein may be used in any body lumen. Furthermore, as discussed in more detail below, the stent150may be disposed around the inner tubular member130.

The stent150may be made from any number of materials, combinations of materials, and constructions. In some examples, the stent150is a self-expanding stent. The stent150may be a wire-form stent formed by one or more helically wrapped wires. However, it should be appreciated that the stent150may be made from other stent constructions or combinations of stent constructions. In other examples, the stent150is a laser-cut stent formed from a single metallic tube with regions cut away for increased flexibility. In yet other examples, the stent150is a braided stent made from a plurality of wires joined together in a cross-hatch configuration. In some examples, the stent150may be a combination of the braided stent and the wire-form stent.

It may be appreciated that the different stent constructions may exhibit particular characteristics such as radial expansive force, flexibility, reduced foreshortening, or migration resistance that may render a certain construction advantageous for a particular use. For example, the helical wrapping pattern of the stent150may be configured to reduce a foreshortening of the stent body upon deployment from an undeployed configuration to the deployed configuration to less than ten percent of a length of the stent body in the undeployed configuration. In such cases, the stent150may be an example of a non-foreshortening stent.

The individual wires or frame of the stent150may be made from any number of metallic materials including, but not limited to, titanium, nitinol, or stainless steel. It should be appreciated that other metallic or non-metallic materials may be used to construct the stent150that provides suitable flexibility, stiffness, and biocompatibility. The stent150may include a polymeric or fabric sleeve (e.g., first material) that covers some or all of the surface of the stent150. Such a sleeve may protect the inner surface of the body lumen from the bare metal of the stent150and may prevent tissue ingrowth. For example, the stent150may include a helical wrapping pattern that is at least partially covered with a first material. In some examples, the stent150is a drug-eluting stent.

The outer sheath105of the system100has an elongate tubular body and an internal lumen extending from its proximal end to the distal end. In general, the outer sheath105may be configured to access a body lumen and to provide a conduit through which one or more devices (e.g., a guidewire145) may pass to facilitate subsequent treatment of the body lumen or associate organs. The outer sheath105may include features that facilitate the direction-controlled delivery of a guidewire145within the body lumen for subsequent delivery of a stent150, a biopsy device, a medicinal delivery element, or any number of other treatment or diagnostic devices.

The outer sheath105may be disposed coaxially along at least a portion of the inner tubular member130such that the stent150is disposed between the inner tubular member130and the outer sheath105while the stent150is in an undeployed configuration. The undeployed configuration may be an example of a stent150constrained within the outer sheath105, an unexpanded configuration of the stent150, or both. In some cases, the outer sheath105may include a braided extrusion in which a braided, distal section of the outer sheath105is fused with a braided, proximal section of the outer sheath105. In some cases, the outer sheath105may include a constant diameter along the length of the outer sheath105.

In some examples, the outer sheath105may include a lubrication coating disposed within an inner surface of the outer sheath105. The lubrication coating may be made from a variety of materials, including but not limited to silicone. In such cases, the lubrication coating may reduce deployment forces by at least thirty percent to ensure accurate placement of the stent150within the body lumen. In some cases, the lubrication coating of the outer sheath105may reduce the friction between the outer sheath105and the stent150as the outer sheath105is retracted over the stent150. The isolation sheath110may be configured to receive the outer sheath105as the outer sheath105is retracted. The isolation sheath110may include a lubrication coating disposed within an inner surface of the isolation sheath110.

The inner tubular member130is generally an elongate, tubular member with a proximal end135and distal end140and is dimensioned to be advanced through the internal lumen of the outer sheath105. The inner tubular member130may be configured to advance through an access site in a wall of the body lumen. In certain embodiments, the inner tubular member130includes one or more internal lumens extending from the proximal end135to the distal end140to house a power wire coupled with the electrocautery tip125in one internal lumen and the guidewire145in another internal lumen. The inner tubular member130may extend from a proximal end of the electrocautery tip125to a lure at the handle end and provide a passageway for the guidewire145. As described below, the inner tubular member130is configured to house the guidewire145. The inner tubular member130may be made of a number of materials, but not limited to polyether ether ketone (PEEK), polytetrafluoroethylene (PTFE), polyimide, or both.

The inner tubular member130may be coupled with an anchoring component120at the distal end140of the inner tubular member130. In certain embodiments, the distal end140of the inner tubular member130includes a tip or bulged portion (e.g., anchoring component120). The stent150may be coupled to the inner tubular member130and the anchoring component120. For example, the stent150may be concentric with the inner tubular member130and the anchoring component120. As such, the inner tubular member130may extend through the lumen of the stent150. For example, the stent150may be disposed coaxially onto the inner tubular member130. The stent150may be positioned between the outer sheath105and the inner tubular member130at the proximal end135of the inner tubular member130.

The anchoring component120may extend through the lumen of the stent150at a distal portion160of the stent150. In such cases, the stent150may be positioned between the outer sheath105and the anchoring component120at the distal end140of the inner tubular member130. For example, the distal portion160of the stent150may be disposed coaxially along the anchoring component120such that the distal portion160of the stent150is disposed between the anchoring component120and the outer sheath105while the stent150is in the undeployed configuration.

The anchoring component120may be made from a variety of materials, including but not limited to silicone. The anchoring component120may be disposed at a distal end140of the inner tubular member130and configured to retain a distal portion160of the stent150in place along the inner tubular member130as the outer sheath105is retracted proximally to deploy the stent150. As described below in further detail, upon retraction of the outer sheath105, the stent150may release from the anchoring component120and expand into a deployed configuration within the body lumen. The deployed configuration may be an example of an unconstrained configuration, an expanded configuration, or both.

The anchoring component120may be an example of a bump, an increased diameter component of the inner tubular member130, a hook, or a combination thereof. In such cases, the anchoring component120may be configured to keep the distal portion160of the stent150stationary as the outer sheath105is retracted. In some examples, the anchoring component120may be 8 mm in length or 4 cm in length for a stent150that is 8-10 cm in length. In some cases, the inner tubular member130may include a single anchoring component120or more than one anchoring component120. For example, the inner tubular member130may include at least three anchoring components120made of polyether block amide (PEBA) and positioned along the inner tubular member130. The anchoring components120may extend 1 cm higher from the outer surface of the inner tubular member130.

The system100may further include a proximal marker115. The proximal marker115may be an example of a proximal marker that is disposed around the inner tubular member130and positioned such that a proximal portion155of the stent150abuts against the proximal marker115while the stent150is in the undeployed configuration. The proximal marker115may be configured to indicate a location of the proximal portion155of the stent150within the system100. The proximal marker115may be configured to retain a proximal portion155of the stent150in place along the inner tubular member130as the outer sheath105is retracted proximally to deploy the stent150. In some cases, the proximal marker115may be coupled with the inner tubular member130such that the proximal marker115remains stationary as the outer sheath105is retracted.

The proximal marker115includes generally an elongate, tubular member and is configured to house the inner tubular member130. In some cases, the proximal marker115may be tapered such that a distal end of the proximal marker115may extend underneath the proximal portion155of the stent150. For example, the proximal marker115may be an example of a proximal anchoring component such that the proximal marker115may be configured to compress the proximal portion155of the stent150between the proximal marker115and the outer sheath105.

The electrocautery tip125may be an example of a distal cutting element coupled with the distal end140of the inner tubular member130and configured to create the access site in the wall of the body lumen. The electrocautery tip125may include a coiled electrode wire that extends radially around a circumference of a distal end of the electrocautery tip125, a single electrode wire that extends longitudinally and in a proximal direction from a distal end of the electrocautery tip125, a single, spiral electrode wire that extends around a distal end of the electrocautery tip125, or an electrode tube. In some case, the electrocautery tip125may include a tapered cover disposed around the electrocautery tip125. The outer sheath105may at least partially overlap the tapered cover. The tapered cover may be made from a variety of materials, including but not limited to silicone or other flexible materials. In some cases, the outer diameter of the electrocautery tip125may be equal to the inner diameter of the outer sheath105. In other examples, the outer diameter of the electrocautery tip125may be greater than the inner diameter of the outer sheath105.

The guidewire145is generally a flexible elongate member configured to slidably advance through the internal lumen of the inner tubular member130. In such cases, the guidewire145may be disposed within the inner tubular member130. The guidewire145may be uniform in size and stiffness along its entire length, or alternatively, may include sections of differing stiffness.

FIG.2illustrates a system200for providing access to a body lumen in accordance with aspects of the present disclosure. The system200generally includes the outer sheath105, the isolation sheath110, the proximal marker115, the anchoring component120(not shown), the electrocautery tip125, the inner tubular member130(not shown), and the stent150, which may be examples of the corresponding components described with reference toFIG.1. The system200may also include a thumbwheel205, a stationary member210, a guidewire lumen220, and a connector port225. The system200can be provided as individual components, selectively combined components, or all together as a kit of components.

The thumbwheel205may be coupled with a proximal end215of the isolation sheath110and configured to retract the outer sheath105proximally. In some cases, the outer sheath105may be bonded with a plastic component at a proximal end of the outer sheath105to the handle assembly230. The actuation of the thumbwheel205may retract the outer sheath105to deploy the stent150. As described below, the outer sheath105may be retracted into the stationary isolation sheath110.

The stationary member210may be an example of a locking pin. The stationary member210may be configured to prevent deployment when the device is inserted into the scope. For example, features of the stationary member210may engage into the carriage to prevent accidental deployment. To begin actuation of the thumbwheel205, the stationary member210may be removed from the handle assembly230. In such cases, the device may be deployed based on removing the stationary member210and actuating the thumbwheel205.

In some cases, the isolation sheath110may stabilize the device against the scope channel and isolate friction that the catheter may experience otherwise in tortuosity. In such cases, the system200may enable accurate deployment of the stent150through the sheath-based delivery system200(e.g., including at least the isolation sheath110and the outer sheath105) to ensure stability of the catheter against the scope. In some cases, the isolation sheath110may include two different diameters along the length of the isolation sheath110to customize interaction with the scope channel.

The isolation sheath110may made of a material such as high-density polyethylene (HDPE). The isolation sheath110may be in contact with the inner diameter of the working channel of the endoscope, thereby inducing friction between the isolation sheath110and working channel. As the thumbwheel is actuated the outer sheath105is retracted, the friction between the isolation sheath110and the working channel may be greater than the friction between the isolation sheath110and the outer sheath105such that the isolation sheath110remains stationary as the outer sheath105is retracted. In such cases, the isolation sheath110may be configured as a barrier between the outer sheath105and the working channel, thereby reducing the overall friction on the system200.

The outer sheath105may be inserted into a handle assembly230, and once assembled, the outer sheath105extends through the handle assembly230to the target body lumen. In some cases, a power wire may be connected to the electrocautery tip125and may be laminated on the inner lumen member by a polyester heat shrink. In such cases, the power wire may extend through the handle assembly230and through the connector port225. The electrode of the electrocautery tip125may be connected through the connector port225in the handle assembly230. In some cases, the electrode may connect to a radiofrequency (RF) generator.

The guidewire lumen220may generally be a tubular structure that is sized to deploy the stent150within the body lumen. The guidewire lumen220may access the human body through the working channel of an endoscope, for example. As will be appreciated, the guidewire lumen220may be made from any number of biocompatible materials or combinations of materials suitable for medical sheaths, catheters, and the like.

FIG.3Aillustrates a stent delivery system300-ain accordance with aspects of the present disclosure. The stent delivery system300-amay be configured to place a stent (not shown) within a first body lumen305to restore luminal flow from a first body lumen305to a second body lumen310, thereby bypassing narrowed areas or blockages within at least the first body lumen305. The stent delivery system300-amay be sized or otherwise adapted to place a stent within any body lumen, such as those associated with the pancreaticobiliary system, the arterial system, the bronchial system, the urinary system, or any other luminal system that may require stent treatment.

The stent delivery system300-amay generally include the isolation sheath110, the outer sheath105, the electrocautery tip125, and the guidewire145, which may be examples of the corresponding components described with reference toFIGS.1and2. The guidewire145may be part of the stent delivery system300-aor may be a separate component. The stent delivery system300-acan be provided as individual components, selectively combined components, or all together as a kit of components.

With reference toFIG.3A, a stent delivery system300-afor providing access to a body lumen is illustrated in accordance with aspects of the present disclosure. The stent delivery system300-amay be examples of or include functionality of the systems or components described with reference to any ofFIGS.1and2. The illustrated portions of the system include the first body lumen305(e.g., a common bile duct), which drains bile from both the cystic duct (which drains from the gallbladder) and the common hepatic duct (which drains from the liver) into the second body lumen310(e.g., duodenum), where the bile mixes and reacts with digesting food.

A clinician may advance an endoscope (e.g., an EUS endoscope) into the lumen of a patient's duodenum (e.g., second body lumen310) to a position in which the bile ducts may be visualized (e.g., via endosonography). The clinician may then access the common bile duct (e.g., first body lumen305) by advancing a separate access device from a working channel of the endoscope, through the wall325of the duodenum (i.e., trans-duodenally), and then through the wall320of the common bile duct.

The clinician may then insert a guidewire145via the separate access device, thereby allowing the stent delivery system300-ato be tracked over the guidewire145. After the stent delivery system300-ais advanced into the common bile duct, the stent delivery system300-amay retract the outer sheath105to position the stent through the first body lumen305and the second body lumen310, as described in reference toFIGS.3B-3E.

During a luminal access and stent delivery procedure, the electrocautery tip125may access the target lumen (e.g., first body lumen305) by piercing a wall320of the first body lumen305, for example. In some examples, a sharpened stylet may be used in conjunction with the electrocautery tip125to facilitate piercing the wall320(e.g., luminal wall). For example, the sharpened stylet may be advanced through the electrocautery tip125until it protrudes from the electrocautery tip125to pierce tissue. In some cases, the guidewire145may be advanced through the outer sheath105and into the first body lumen305as the electrocautery tip125accesses the first body lumen305. The electrocautery tip125may access the target lumen (e.g., first body lumen305) by piercing a wall325of the second body lumen310prior to piercing the wall320of the first body lumen305. In such cases, the electrocautery tip125may exit the second body lumen310and target access of the first body lumen305. The first body lumen305may be an example of the biliary duct, and the second body lumen310may be an example of the duodenum.

Referring still toFIG.3A, to place the stent delivery system300-awithin the first body lumen305, an access site315is formed through the wall320of the first body lumen305, and the guidewire145is then advanced through the access site315and into the first body lumen305. In some cases, to access the first body lumen305, the electrocautery tip125may apply energy to the wall320of the first body lumen305and access, via the access site315, the first body lumen305based on applying the energy to the wall320of the first body lumen305. In some cases, prior to accessing the first body lumen305, the electrocautery tip125may apply energy to the wall325of the second body lumen310and access the first body lumen305based on applying the energy to the wall325of the second body lumen310. For example, the electrocautery tip125may cut the tissue in contact with the electrode of the electrocautery tip125. The stent delivery system300-a(e.g., a stent delivery apparatus) may be advanced through the first body lumen305and the second body lumen310.

The stent delivery system300-amay be used to access and provide treatment to one or more body lumens within the gastrointestinal system or pancreaticobiliary system, for example. It may be appreciated that the stent delivery system300-amay also be used to provide access or treatment to other organs or luminal systems within the body such as the arterial system, the bronchial system, the urinary system, or any other luminal system were maneuverability and accuracy is desirable.

The stent delivery system300-amay be configured for choledochoduodenostomy (CDS) and hepaticogastrostomy (HGS) procedures in which the stent is implanted across two tissues layers (e.g., duodenum to common bile duct or stomach to intrahepatic duct). After the biliary duct is accessed and guidewire145is placed, the tract across the two tissues is dilated mechanically or via electrocautery followed by insertion of stent delivery system300-ato implant the stent. The tract dilation step may increase a rate of acute adverse events. In some cases, accurate stent deployment may be dependent on operator skillset and the operator may dynamically adjust the delivery system position after deployment is initiated and the stent is deployed. Therefore, techniques may be desired to utilize the stent delivery system300-ato enable increased deployment accuracy within the body lumen.

In some cases, the stent delivery system300-amay be configured for transmittal biliary drainage. In such cases, the stent may bridge between the second body lumen310(e.g., the duodenum) and a portion of the first body lumen305(e.g., the biliary duct) to create a bridge to bypass an obstruction. The obstruction may be an example of a distal malignant biliary obstruction that obstructs drainage. To access the first body lumen305, the stent delivery system300-amay perform a track dilation based on a mechanical dilation via a balloon or electrical dilation via a knife. In some cases, the track dilation may be performed by the electrocautery tip125. In such cases, the stent delivery system300-amay enable the track dilation step to be performed together with the delivery the stent as the electrocautery tip125is coupled with the distal end of the inner tubular member within the outer sheath105.

In some examples described herein, the handle assembly is coupled with an endoscope and the outer sheath105is guided via endoscopic ultrasound (EUS) to provide access to one or more body lumens or organs associated with the pancreaticobiliary system for the purpose of providing treatment. For example, the stent delivery system300-amay be configured to provide access to at least the common biliary duct to facilitate subsequent procedures to treat narrowed areas or blockages within the bile duct and create a bypass around the narrowed areas or blockages within the bile duct to provide access to the stomach and from the biliary duct via the stent.

FIG.3Billustrates a stent delivery system300-bwithin the first body lumen305in accordance with aspects of the present disclosure. Once the guidewire145is in place, the outer sheath105is advanced into the first body lumen305, over the guidewire145, through the access site315, and into the first body lumen305.

The stent (not shown) may be positioned, in the undeployed configuration, through an access site315in a wall320of a first body lumen305. In such cases, the stent may be constrained within the outer sheath105, and the outer sheath105may be advanced through the access site315. The stent may be positioned in the first body lumen305after advancing the stent delivery apparatus through the first body lumen305and the second body lumen310. In such cases, the stent may be positioned based on accessing the first body lumen305, accessing the second body lumen310, or both. In some cases, the stent may be positioned after advancing the guidewire145through the access site315.

The inner tubular member (not shown) may be operatively coupled with the stent. As such, the inner tubular member and stent may be advanced over the guidewire145and into the first body lumen305. As discussed in more detail below, the stent may be attached to the inner tubular member between the outer sheath105and the anchoring component (not shown) coupled with the inner tubular member.

Once in the first body lumen305, the outer sheath105, the inner lumen member, and the anchoring component may be advanced distally. In some cases, the outer sheath105and the inner lumen member may be advanced distally such that the outer sheath105and the inner lumen member extend through and into the biliary duct. The outer sheath105and the inner lumen member may be advanced until a distal end of the marker (not shown) is aligned with the wall325of the second body lumen310. In such cases, prior to retracting the outer sheath105, the anchoring component may be positioned within the first body lumen305, and the marker may be positioned within the second body lumen310such that the stent traverses the first body lumen305and the second body lumen310.

The outer sheath105may, be disposed around the inner lumen member and the anchoring component. As such, the distal portion of the stent is disposed between the anchoring component and the outer sheath105, and the proximal portion of the stent is disposed between the inner lumen member and the outer sheath105. For example, the distal portion of the stent may be compressed in the undeployed configuration between the anchoring component and the outer sheath. In some cases, the access site315may be covered by the outer sheath105.

FIG.3Cillustrates a stent delivery system300-cwith a flared portion of the stent150deployed in accordance with aspects of the present disclosure. Once the outer sheath105is removed through the access site315, the distal portion160of the stent150may deploy. As the outer sheath105is withdrawn through the access site315, the inner lumen member (not shown) and the anchoring component120may remain stationary, and the distal portion160of the stent150may be exposed within the first body lumen305. Once the desired anatomical position of the stent150has been achieved within the first body lumen305, the outer sheath105may be retracted.

The outer sheath105may be retracted proximally and past the anchoring component120disposed at a distal portion of an inner tubular member based on positioning the stent150. For example, the distal portion160of the stent150may be disposed coaxially along the anchoring component120such that the distal portion160of the stent150is disposed between the anchoring component120and the outer sheath105while the stent150is in the undeployed configuration. The distal portion160of the stent150may be deployed from the outer sheath105into a deployed configuration within the first body lumen305based on retracting the outer sheath105past the anchoring component120.

In some cases, the distal portion160of the stent150may be released from the anchoring component120and into the deployed configuration in response to retracting the outer sheath105past the anchoring component120. For example, the distal portion160of the stent150may expand from the undeployed configuration to the deployed configuration while the outer sheath105is retracted based on a pressure being released between the anchoring component120and the outer sheath105as the outer sheath105is retracted. In such cases, the distal portion160of the stent150is no longer compressed between the outer sheath105and the anchoring component120and is free to expand within the first body lumen305.

The distal portion160of the stent150may include a flared portion. In such cases, the flared portion may expand within the first body lumen305in direct response to retracting the outer sheath105past the anchoring component120. As the outer sheath105is removed through the access site315, the distal portion160of the stent150expands to expose the flared portion. As the distal portion160of the stent150expands, the flared portion contacts the wall320of the first body lumen305. The flared portion (e.g., distal portion160) of the stent150may be anchored within the first body lumen305such that the distal portion160of the stent150remains in a fixed position. In that case, the distal portion160prevents the stent150from being further withdrawn through the access site315. The clinician may be able to feel the resistance of the flared portion against the first body lumen305and may therefore infer the location of the stent150. Additionally or alternatively, the distal portion160of the stent150may be viewed under fluoroscopy or similar imaging techniques to infer the location of the stent150.

The distal portion160of the stent150may be retained in place along the inner tubular member as the outer sheath105is retracted past the anchoring component120based on the distal portion160of the stent150being disposed (e.g., compressed) between the anchoring component120and the outer sheath105. While the outer sheath105is retracted, the anchoring component120and the inner tubular member may be maintained in a locked position (e.g., stationary with respect to the withdrawn outer sheath105). As the outer sheath105is retracted, the isolation sheath110is maintained in a locked position while retracting and withdrawing the outer sheath105into the isolation sheath110.

The friction between the anchoring component120and the distal portion160of the stent150may keep the stent150in place along the inner tubular member as the outer sheath105is retracted. In some cases, the friction between the stent150and the outer sheath105may keep the stent150in place as the outer sheath105is retracted such that after the outer sheath105is retracted past the anchoring component120(e.g., clears the anchoring component120), the distal portion160of the stent150expands from an undeployed to a deployed configuration.

In such cases, the outer sheath105may be retracted to a first position (e.g., past a distal end of the anchoring component120), and the distal portion160of the stent150may deploy in a same location as compared to a location prior to retracting the outer sheath105. Once the outer sheath105is retracted past the distal end of the anchoring component120, the distal portion160of the stent150that was positioned between the outer sheath105and the anchoring component120may expand into the first body lumen305and anchor itself to the first body lumen305. In such cases, the anchored distal portion160of the stent150may maintain the stent in a stationary position as the outer sheath105is retracted.

FIG.3Dillustrates a stent delivery system300-dwith the stent150fully deployed in accordance with aspects of the present disclosure. As the outer sheath105is further withdrawn proximally, the inner lumen member (not shown) may remain stationary, and the stent150may be exposed within the first body lumen305and into the second body lumen310. To deploy the stent150within the first body lumen305and second body lumen310, the outer sheath105may be retracted past a distal end330of the proximal marker115. In the case of a non-foreshortening stent, the stent150expands to contact the inner surface of the first body lumen305and the inner surface of the second body lumen310such that the stent150forms a bridge between the first body lumen305and the second body lumen310.

The distal end330the proximal marker115may be aligned with the wall325of the second body lumen310. While the outer sheath105is retracted, the proximal marker115may be maintained in a locked position after aligning the distal end330of the proximal marker115with the wall325of the second body lumen310. Once the outer sheath105is retracted past the distal end330of the proximal marker115, the proximal portion155of the stent150may expand from within the outer sheath105in response to withdrawing the outer sheath105past the proximal marker115. For example, the proximal portion155of the stent150may expand from within the outer sheath105such that upon fully exiting the outer sheath105, the proximal portion155expands to a deployed configuration within the second body lumen310. In such cases, the entire portion of the stent150may expand such that at least a portion of the stent150extends through the first body lumen305and into the second body lumen310.

The proximal portion155of the stent150may be retained in place along the inner tubular member as the outer sheath105is retracted past the proximal marker115based on the proximal portion155of the stent150being disposed (e.g., compressed) between the inner lumen member and the outer sheath105. In some cases, the proximal portion155of the stent150may be retained in place as the outer sheath105is retracted based on the proximal portion of the stent150abutting a proximal end of the proximal marker115. While the outer sheath105is retracted, the inner tubular member may be maintained in a locked position (e.g., stationary with respect to the withdrawn outer sheath105). As the outer sheath105is retracted, the isolation sheath110is maintained in a locked position while retracting and withdrawing the outer sheath105into the isolation sheath110.

In such cases, the outer sheath105may be retracted to a second position (e.g., past the distal end330of the proximal marker115), and the proximal portion155of the stent150may deploy in a same location as compared to a location prior to retracting the outer sheath105. Once the outer sheath105is retracted past the distal end330of the proximal marker115, the proximal portion155of the stent150that was positioned between the outer sheath105and the inner lumen member may expand into the second body lumen310and anchor itself to the second body lumen310. In such cases, the anchored proximal portion155of the stent150may maintain the stent150in a stationary position as the inner lumen is retracted after the stent150fully deploys.

The proximal portion155of the stent150may include a flared portion. In such cases, the flared portion may expand within the second body lumen310in direct response to retracting the outer sheath105past the distal end330of the proximal marker115. As the outer sheath105is withdrawn past the proximal marker115and into the isolation sheath110, the proximal portion155of the stent150expands to expose the flared portion. As the proximal portion155of the stent150expands, the flared portion contacts the wall325of the second body lumen310. The flared portion (e.g., proximal portion155) of the stent150may be anchored within the second body lumen310such that the proximal portion155of the stent150remains in a fixed position.

FIG.3Eillustrates a stent delivery system300-ewith the system removed in accordance with aspects of the present disclosure. Once the stent150fully expands, the inner tubular member130, the anchoring component120, the electrocautery tip125, and the guidewire145are withdrawn through the access site315. Once the outer sheath105is fully retracted into the isolation sheath110, the inner tubular member130, the anchoring component120, and the electrocautery tip125may be removed from the first body lumen305, through the access site315, and from the second body lumen310after the stent150fully deploys. In such cases, the inner tubular member130and the anchoring component120may be retracted into the outer sheath105until the distal end of the outer sheath105at least partially overlaps with the electrocautery tip125. For example, the inner tubular member130may be pulled from a proximal end of the inner tubular member130. The stent delivery apparatus (e.g., stent delivery system300-e) may be removed through the first body lumen305and the second body lumen310after expanding the stent150.

The flared portion (e.g., distal portion160) of the stent150may be anchored within the first body lumen305such that the distal portion160of the stent150remains in a fixed position. In such cases, the distal portion160of the stent150may be compressed against the wall320of the first body lumen305based on deploying the distal portion160of the stent150from the outer sheath105. Furthermore, the stent150may at least partially cover the access site315.

The flared portion (e.g., proximal portion155) of the stent150may be anchored within the second body lumen310such that the proximal portion155of the stent150remains in a fixed position. In such cases, the proximal portion155of the stent150may be compressed against the wall325of the second body lumen310based on expanding the proximal portion155of the stent150from within the outer sheath105. Furthermore, the stent150may at least partially cover the access site of the second body lumen310.

FIG.4illustrates a flowchart of a method400for stent delivery and positioning for transluminal application in accordance with aspects of the present disclosure.

At405, the method may include positioning the stent in an undeployed configuration through an access site in a wall of a first body lumen. The operations of405may be performed in accordance with examples as disclosed herein.

At410, the method may include retracting an outer sheath proximally and past an anchoring component disposed at a distal portion of an inner tubular member based at least in part on positioning the stent, wherein a distal portion of the stent is disposed coaxially along the anchoring component such that the distal portion of the stent is disposed between the anchoring component and the outer sheath while the stent is in the undeployed configuration. The operations of410may be performed in accordance with examples as disclosed herein.

At415, the method may include deploying the distal portion of the stent from the outer sheath into a deployed configuration within the first body lumen based at least in part on retracting the outer sheath past the anchoring component. The operations of415may be performed in accordance with examples as disclosed herein.

At420, the method may include expanding a proximal portion of the stent from within the outer sheath such that upon fully exiting the outer sheath, the proximal portion expands to a deployed configuration within a second body lumen. The operations of420may be performed in accordance with examples as disclosed herein.

FIG.5illustrates a flowchart of a method500for stent delivery and positioning for transluminal application in accordance with aspects of the present disclosure.

At505, the method may include positioning the stent in an undeployed configuration through an access site in a wall of a first body lumen. The operations of505may be performed in accordance with examples as disclosed herein.

At510, the method may include retracting an outer sheath proximally and past an anchoring component disposed at a distal portion of an inner tubular member based at least in part on positioning the stent, wherein a distal portion of the stent is disposed coaxially along the anchoring component such that the distal portion of the stent is disposed between the anchoring component and the outer sheath while the stent is in the undeployed configuration. The operations of510may be performed in accordance with examples as disclosed herein.

At515, the method may include retaining the distal portion of the stent in place along the inner tubular member as the outer sheath is retracted past the anchoring component based at least in part on the distal portion of the stent being disposed between the anchoring component and the outer sheath. The operations of515may be performed in accordance with examples as disclosed herein.

At520, the method may include deploying the distal portion of the stent from the outer sheath into a deployed configuration within the first body lumen based at least in part on retracting the outer sheath past the anchoring component. The operations of520may be performed in accordance with examples as disclosed herein.

At525, the method may include expanding a proximal portion of the stent from within the outer sheath such that upon fully exiting the outer sheath, the proximal portion expands to a deployed configuration within a second body lumen. The operations of525may be performed in accordance with examples as disclosed herein.

It should be noted that these methods describe possible implementation, and that the operations and the steps may be rearranged or otherwise modified such that other implementations are possible. In some examples, aspects from two or more of the methods may be combined. For example, aspects of each of the methods may include steps or aspects of the other methods, or other steps or techniques described herein.

While several embodiments of the present disclosure have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means or structures for performing the functions or obtaining the results or one or more of the advantages described herein, and each of such variations or modifications is deemed to be within the scope of the present disclosure. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, or configurations will depend upon the specific application or applications for which the teachings of the present disclosure is/are used.

Those skilled in the art will recognize or be able to ascertain using no more than routine experimentation, many equivalents to the specific embodiments of the disclosure described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, the disclosure may be practiced otherwise than as specifically described and claimed. The present disclosure is directed to each individual feature, system, article, material, kit, or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, or methods, if such features, systems, articles. materials, kits, or methods are not mutually inconsistent, is included within the scope of the present disclosure.

All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, or ordinary meanings of the defined terms.

The indefinite articles “a” and “an,” as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean “at least one.” Also, as used herein, including in the claims, “or” as used in a list of items (for example, a list of items prefaced by a phrase such as “at least one of” or “one or more”) indicates an inclusive list such that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C).