Patent ID: 12233226

While the disclosure is amenable to various modifications and alternative forms, specifics thereof have been shown by way of example in the drawings and will be described in detail. It should be understood, however, that the intention is not to limit the invention to the particular embodiments described. On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure.

DETAILED DESCRIPTION

For the following defined terms, these definitions shall be applied, unless a different definition is given in the claims or elsewhere in this specification.

All numeric values are herein assumed to be modified by the term “about”, whether or not explicitly indicated. The term “about” generally refers to a range of numbers that one of skill in the art would consider equivalent to the recited value (e.g., having the same function or result). In many instances, the terms “about” may include numbers that are rounded to the nearest significant figure.

The recitation of numerical ranges by endpoints includes all numbers within that range (e.g. 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4, and 5).

As used in this specification and the appended claims, the singular forms “a”, “an”, and “the” include plural referents unless the content clearly dictates otherwise. As used in this specification and the appended claims, the term “or” is generally employed in its sense including “and/or” unless the content clearly dictates otherwise.

It is noted that references in the specification to “an embodiment”, “some embodiments”, “other embodiments”, etc., indicate that the embodiment described may include one or more particular features, structures, and/or characteristics. However, such recitations do not necessarily mean that all embodiments include the particular features, structures, and/or characteristics. Additionally, when particular features, structures, and/or characteristics are described in connection with one embodiment, it should be understood that such features, structures, and/or characteristics may also be used connection with other embodiments whether or not explicitly described unless clearly stated to the contrary.

The following detailed description should be read with reference to the drawings in which similar elements in different drawings are numbered the same. The drawings, which are not necessarily to scale, depict illustrative embodiments and are not intended to limit the scope of the invention.

In endoscopy, a frequent medical condition arises when a patient presents with abdominal pain with or without associated jaundice. The etiology is usually some type of obstruction in the biliary tree which prevents bile from flowing naturally from the proximal tree into the duodenum. The blockage may be the result of biliary stones caught in the lumen of the ducts or a tumor which is either in the wall of the duct or impinging upon the wall from adjacent tissue. When such a stricture occurs the duct proximal to the stricture dilates and the duct distal to the stricture receives a reduced flow of bile. In order to relieve the patient's symptoms, gastroenterologists seek to find a method for resuming the flow of bile from the proximal dilated duct into the duodenum. Some interventions contemplated for reliving symptoms may include placing a stent across the stricture to drain the proximal duct, removing a stone, and/or the like.

The most common method of placing a stent across the stricture is to perform an endoscopic retrograde cholangio-pancreatography (ERCP) where a side-viewing endoscope is placed in the duodenum at the location of the biliary papilla and a guidewire is placed through the papilla and up the biliary duct, across the stricture, in a retrograde fashion. Such procedures may be challenging. For example, depending on the location, geometry, and mechanics of the stricture, deep cannulation of the proximal duct may be difficult if not be possible. Furthermore, when the physician attempts to access the biliary duct, they may inadvertently cannulate the pancreatic duct. Inadvertent cannulation of the pancreatic duct could lead to complications such as pancreatitis. Disclosed herein are devices and methods that address these and other issues, for example by utilizing antegrade (e.g., non-papillary) stricture crossing.

FIG.1schematically depicts an example medical device10for crossing strictures along the biliary and/or pancreatic tract in accordance with the present disclosure. The medical device10may take the form of a guidewire10(e.g., a variable stiffness guidewire10). In general, the guidewire10may have a variable stiffness that allows the guidewire10to be used for antegrade stricture crossing. This may include the ability to change (e.g., increase) the stiffness of the guidewire10during navigation in order to more efficiently cross the stricture.

The structure and form of the guidewire10may vary. For example, the guidewire10may include a polymer tip, spring tip, angled tip, and/or other structures/configurations. In some instances, the guidewire10may include a core member or wire12. A coil member14may be disposed along at least a portion of the core wire12. In general, the coil member14may be configured to shift between a first or uncompressed configuration and a second or compressed configuration. When the coil member14is in the first configuration, the guidewire10may have a relatively high level of flexibility. When the coil member14is shifted to the second configuration, the guidewire10may have a relatively high level of stiffness. In at least some instances, the coil member is configured to be advanced across a biliary and/or pancreatic stricture when in the compressed configuration. A tip member16may be disposed at a distal end of the coil member14. In this example, the tip member16is depicted as a solder ball tip. However, in other instances, the tip member16may take the form of a “floppy” tip, a spring tip, a polymer tip, an angled tip, a tapered tip, and/or the like.

In some instances, the coil member14may be replaced by a tubular member having a plurality of slots (e.g., laser cut slots) formed therein. The tubular member may have one or more preferred bending direction, for example determined by the configuration of the slots. In some instances, the tubular member may include one or more steering wires that allow the guidewire10to be steered.

A sleeve18may be disposed along the coil member14. The sleeve18may have a substantially constant outer diameter. In at least some instances, the sleeve18may be configured to keep substantially the same outer diameter regardless of whether the coil member14is in the first configuration or the second configuration (and/or any other configuration). The sleeve18may include a polymeric material. In at least some instances, the sleeve18may include a lubricious material (e.g., the sleeve18may be formed from a lubricious material and/or the sleeve18may include a lubricous layer or coating). In some instances, the sleeve18may have insulating properties, which may allow the guidewire10to be used with radiofrequency or other electrical devices. The sleeve18may also provide the coil member14with a level of torsional support/strength (e.g., when the coil member14is in the first configuration) that allows a clinician to efficiently apply torque to the guidewire10or otherwise steer the guidewire10toward a target (e.g., a stricture along the biliary and/or pancreatic tract). In some instances, the guidewire10may be free of the sleeve18(e.g., a sleeve like the sleeve18is not positioned along the coil member14).

In some instances, the coil member14is disposed along a distal portion of the guidewire10. In at least some of these instances, a shaft or tubular member19may extend proximally from a proximal end of the coil member14. The tubular member19may take the form of a hyoptube. In other instances, the coil member14may extend along some or all of the proximal portion of the guidewire10. For example, in some instances the coil member14may extend to the proximal end of the guidewire10.

An actuation member20may be coupled to the coil member14. The actuation member20may take of the form of a wire (e.g., a round wire, a ribbon wire, a stranded wire, a stiffened rod, and/or the like) that extends along the interior or the exterior of the coil member14toward the proximal end of the guidewire10. In at least some instances, the actuation member20may be attached to the distal end of the coil member14. The actuation member20may be configured to shift the coil member14between a first or uncompressed configuration (e.g., as shown inFIG.2) and a second or compressed configuration (e.g., as shown inFIG.3). For example, the actuation member20may be proximally retracted (e.g., pulled/tensioned) to apply compressive forces onto the coil member14. It can be appreciated that as the actuation member20is further tensioned, additional compressive force is applied to the coil member14, which increases the stiffness of the guidewire10. While the configurations of the coil member14may be considered to be described as binary in nature (e.g., a first and a second configuration), in reality the state of the coil member14may be understood as being shifted across a range of configurations that result in a continuum of flexibility/stiffness characteristics for the guidewire10.

FIG.4illustrates a handle22may be coupled to the guidewire10. The handle22may include a slidable member24that can slide along a region26of the handle22. The slidable member24may be coupled to the actuation member20. Thus, proximal movement of the slidable member24may result in proximal retraction of the actuation member20(e.g., and increased stiffness of the guidewire10). In some instances, the handle22may include a lock configured to secure the axial position of the slidable member24relative to the region26.

FIG.5illustrates an overview of the biliary system or tree. A portion of the duodenum74is shown. The papilla of Vater76(e.g., also known as the ampulla of Vater or simply the papilla) is located at the illustrated portion of the duodenum74. The papilla76generally forms the opening where the pancreatic duct78and the common bile duct80can empty into the duodenum74. The hepatic ducts, denoted by the reference numeral82, are connected to the liver84and empty into the bile duct80. Similarly, the cystic duct86, being connected to the gall bladder88, also empties into the bile duct80. In general, an endoscopic or biliary procedure may include advancing a medical device to a suitable location along the biliary tree and then performing the appropriate intervention.

In some instances, it may be desirable to navigate the guidewire10past a stricture94along the pancreatic and/or biliary tract. This may include an antegrade crossing procedure (as opposed to a retrograde or papillary crossing procedure). For example,FIG.6depicts an endoscope90extending into the duodenum74. In some instances, a catheter or introducer sheath40may be advanced through the endoscope90(e.g., through a channel formed in the endoscope90). The introducer sheath40may be directed toward the wall of the duodenum74with the elevator92of the endoscope90. In some instances, a needle/sharp91may be disposed within the introducer sheath40. The needle/sharp91may help to pierce through the wall of the duodenum74, through tissue, and into a position along the pancreatic and/or biliary tract adjacent to (e.g., proximal to) a stricture94. In this example, the stricture94is disposed along the bile duct80.

In order to cross the stricture94, the guidewire10may be navigated toward the stricture94(e.g., through the introducer sheath40, a guide catheter, and/or the like) as schematically depicted inFIG.7. When navigating the guidewire10through tissue, it may be desirable to vary (e.g., increase) the stiffness. In some of these and in other instances, the stiffness may be further varied (e.g., the stiffness may be decreased) while navigating the guidewire10along the pancreatic and/or biliary tract toward the stricture94. In some of these and in other instances, the stiffness may be further varied (e.g., the stiffness may be increased) while navigating the guidewire10beyond the stricture as depicted inFIG.8.

The materials that can be used for the various components of the devices disclosed herein may include those commonly associated with medical devices. For simplicity purposes, the following discussion makes reference to the guidewire10. However, this is not intended to limit the devices and methods described herein, as the discussion may be applied to other similar tubular members and/or components of tubular members or devices disclosed herein.

The guidewire10may be made from or otherwise includes a metal, metal alloy, polymer (some examples of which are disclosed below), a metal-polymer composite, ceramics, combinations thereof, and the like, or other suitable material. Some examples of suitable polymers may include polytetrafluoroethylene (PTFE), ethylene tetrafluoroethylene (ETFE), fluorinated ethylene propylene (FEP), polyoxymethylene (POM, for example, DELRIN® available from DuPont), polyether block ester, polyurethane (for example, Polyurethane 85A), polypropylene (PP), polyvinylchloride (PVC), polyether-ester (for example, ARNITEL® available from DSM Engineering Plastics), ether or ester based copolymers (for example, butylene/poly(alkylene ether) phthalate and/or other polyester elastomers such as HYTREL® available from DuPont), polyamide (for example, DURETHAN® available from Bayer or CRISTAMID® available from Elf Atochem), elastomeric polyamides, block polyamide/ethers, polyether block amide (PEBA, for example available under the trade name PEBAX®), ethylene vinyl acetate copolymers (EVA), silicones, polyethylene (PE), high-density polyethylene, low-density polyethylene, linear low density polyethylene (for example REXELL®), polyester, polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polytrimethylene terephthalate, polyethylene naphthalate (PEN), polyetheretherketone (PEEK), polyimide (PI), polyetherimide (PEI), polyphenylene sulfide (PPS), polyphenylene oxide (PPO), poly paraphenylene terephthalamide (for example, KEVLAR®), polysulfone, nylon, nylon-12 (such as GRILAMID® available from EMS American Grilon), perfluoro(propyl vinyl ether) (PFA), ethylene vinyl alcohol, polyolefin, polystyrene, epoxy, polyvinylidene chloride (PVdC), poly(styrene-b-isobutylene-b-styrene) (for example, SIBS and/or SIBS 50A), polycarbonates, ionomers, biocompatible polymers, other suitable materials, or mixtures, combinations, copolymers thereof, polymer/metal composites, and the like. In some embodiments the sheath can be blended with a liquid crystal polymer (LCP). For example, the mixture can contain up to about 6 percent LCP.

Some examples of suitable metals and metal alloys include stainless steel, such as 304V, 304L, and 316LV stainless steel; mild steel; nickel-titanium alloy such as linear-elastic and/or super-elastic nitinol; other nickel alloys such as nickel-chromium-molybdenum alloys (e.g., UNS: N06625 such as INCONEL® 625, UNS: N06022 such as HASTELLOY® C-22®, UNS: N10276 such as HASTELLOY® C276®, other HASTELLOY® alloys, and the like), nickel-copper alloys (e.g., UNS: N04400 such as MONEL® 400, NICKELVAC® 400, NICORROS® 400, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N® and the like), nickel-molybdenum alloys (e.g., UNS: N10665 such as HASTELLOY® ALLOY B2®), other nickel-chromium alloys, other nickel-molybdenum alloys, other nickel-cobalt alloys, other nickel-iron alloys, other nickel-copper alloys, other nickel-tungsten or tungsten alloys, and the like; cobalt-chromium alloys; cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®, and the like); platinum enriched stainless steel; titanium; combinations thereof; and the like; or any other suitable material.

It should be understood that this disclosure is, in many respects, only illustrative. Changes may be made in details, particularly in matters of shape, size, and arrangement of steps without exceeding the scope of the disclosure. This may include, to the extent that it is appropriate, the use of any of the features of one example embodiment being used in other embodiments. The invention's scope is, of course, defined in the language in which the appended claims are expressed.