MEDICAL DEVICES WITH ENHANCED ECHOGENICITY

Medical devices including medical devices with enhanced echogenicity are disclosed. An example medical device may include a polymeric catheter shaft having a distal end region. The distal end region may include a plurality of hyperechoic particles disposed therein.

TECHNICAL FIELD

The present disclosure pertains to medical devices, and methods for manufacturing medical devices. More particularly, the present disclosure pertains to medical devices with enhanced echogenicity.

BACKGROUND

BRIEF SUMMARY

This disclosure provides design, material, manufacturing method, and use alternatives for medical devices. A medical device with enhanced echogenicity is disclosed. The medical device comprises: a polymeric catheter shaft having a distal end region; and wherein the distal end region includes a plurality of hyperechoic particles disposed therein.

Alternatively or additionally to any of the embodiments above, the plurality of hyperechoic particles includes microspheres.

Alternatively or additionally to any of the embodiments above, the plurality of hyperechoic particles includes hollow microspheres.

Alternatively or additionally to any of the embodiments above, the plurality of hyperechoic particles includes hollow glass microspheres.

A medical device with enhanced visualization properties is disclosed. The medical device comprises: a medical device body configured to be disposed within a body lumen, the medical device body including a hyperechoic region comprising a polymer and a scattering member configured to scatter ultrasonic energy in order to enhance ultrasonic visualization.

Alternatively or additionally to any of the embodiments above, the medical device body includes an access canula.

Alternatively or additionally to any of the embodiments above, the medical device body includes a catheter shaft.

Alternatively or additionally to any of the embodiments above, the medical device body includes a section of a balloon catheter.

Alternatively or additionally to any of the embodiments above, the medical device body includes a section of a retrieval basket or a retrieval snare.

Alternatively or additionally to any of the embodiments above, the medical device body includes a stent or a section of a stent delivery system.

Alternatively or additionally to any of the embodiments above, the medical device body includes a catheter shaft comprising an inner layer, an outer layer, and an undulating layer disposed between the inner layer and the outer layer.

Alternatively or additionally to any of the embodiments above, the undulating layer includes one or more undulations.

Alternatively or additionally to any of the embodiments above, the undulating layer defines one or more air pockets along the catheter shaft.

Alternatively or additionally to any of the embodiments above, the medical device body includes a plurality of hyperechoic particles.

Alternatively or additionally to any of the embodiments above, the plurality of hyperechoic particles includes microspheres.

Alternatively or additionally to any of the embodiments above, the plurality of hyperechoic particles includes hollow microspheres.

Alternatively or additionally to any of the embodiments above, the plurality of hyperechoic particles includes hollow glass microspheres.

A medical device is disclosed. The medical device comprises: a catheter shaft including an inner layer, an outer layer, and an undulating member disposed between the inner layer and the outer layer; and wherein the undulating member defines a plurality of air pockets within the catheter shaft that are configured to scatter ultrasonic energy in order to enhance ultrasonic visualization of the catheter shaft.

Alternatively or additionally to any of the embodiments above, the undulating member includes a plurality of axially-extending undulations.

Alternatively or additionally to any of the embodiments above, the undulating member includes a plurality of radially-extending undulations.

DETAILED DESCRIPTION

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 “of” is generally employed in its sense including “and/of” unless the content clearly dictates otherwise.

A number of medical interventions utilize ultrasound to help guide and/or visualize a medical device and/or target anatomy. For example, endoscopic ultrasound (EUS) procedures may be performed with a specialized scope that uses high frequency soundwaves to visualize nearby structures. The relative density and geometry of items in field view play a role in EUS “visibility” such that features like air pockets appear brightly lit on the feedback screen.

Some EUS include treating patients where endoscopic retrograde cholangiopancreatography (ERCP) for biliary drainage fails. EUS can be used to recover these failed ERCP procedures either through a recover rendezvous procedure or direct biliary drainage. Such procedures may start with an EUS access procedure to gain guidewire access into the common bile, intrahepatic, or pancreatic ducts. During these procedures, a device may be passed through the working channel of a specialized scope. The device may be used to puncture and cannulate the target anatomy in preparation for a guidewire to gain access (through and anchored by the access cannula). In some instances, puncture and cannulation are performed together by a sharp and access cannula, before the sharp is retracted to allow for passage of a guidewire, through the cannula and into the patient target anatomy.

Metallic sharps, which may include echogenic features, may have a tendency to scatter ultrasonic energy, thereby allowing for suitable visualization. Access cannulas may be made from polymeric materials, which may have a lower tendency to scatter ultrasonic energy and, thus, may harder to visualize with ultrasound. Consequently, fluoroscopic visualization may be used to visualize the access cannula and determine the position of the sharp and/or access cannula relative to one another (e.g., including sharp offset) and/or the anatomy. Disclosed herein are medical devices that are designed to have enhanced echogenicity. This may include medical devices such as access cannulas, catheters (including balloon catheters), snare and/or basket devices, delivery systems, stents, and/or the like.

FIG. 1 schematically depicts a system 10 for a medical intervention. In this example, an EUS procedure is depicted where a catheter or access cannula 12 is used to access a target location. A sharp or puncture member 14 may be disposed within the access cannula 12. In some instances, a guiding device or scope 16 may be used to guide the access cannula 12. The guiding device or scope 16 may be component of the access cannula 12. Alternatively, the guiding device or scope 16 may be a separate device, for example that can be used with the access cannula 12.

In some instances, the sharp 14 may include one or more echogenic features. For example, the sharp 14 may include laser cuts and/or markings 18, 18′. Different arrangements of the cuts/markings 18, 18′ are schematically depicted in FIG. 1. For example, in some instances a singular axial (e.g., vertical) cut 18 may be formed in the sharp 14. Alternatively, multiple cuts such as transverse cuts 18′ may be formed in the sharp 14. It can be appreciated that a variety of a cuts and/or markers can be utilized for the sharp 14, for example to increase the echogenicity of the sharp 14.

FIG. 2 schematically depicts an example ultrasound display system 20. The system 20 may include a display 22. As shown on the display, the distal the sharp 14 may be visible. For example, the markings 18′ may be visible on the display 22. The access cannula 12 may also visible, but to a lesser extent as represented in FIG. 2 by dashed/phantom lines. To further visualize the access cannula 12, fluoroscopic visualization processes may be utilized.

As indicated herein, it may be desirable to enhance echogenicity of various medical devices so that such devices may be efficiently visualized using ultrasound. For example, FIG. 3 illustrates another example medical device or shaft 12′, which may be similar in form and function to other devices disclosed herein. In this example, the shaft 12′ may take the form of a tube. The tube 12′ may be a catheter, access cannula, and/or another similar medical device.

The tube 12′ may include a polymeric substrate or resin 24 having plurality of echogenic particles 26 therein as shown in FIG. 4. Such particles 26 may take the form of microspheres, nanospheres, hollow microspheres, hollow nanospheres, glass microspheres, glass nanospheres, hollow glass microspheres, hollow glass nanospheres, air pockets, combinations thereof, glass, polymeric particles, ceramic materials, metallic particles, salt, blowing agents, a microlumen (e.g., a relatively small passageway or lumen formed into the tube wall), a nanotube (e.g., a carbon nanotube), a composite material (e.g., carbon fiber), combinations thereof, and/or the like. The echogenic particles 26 may have a suitable size such as about 1-500 microns or about 5-150 microns. The echogenic particles 26 may be similar or uniform in size. Alternatively, the echogenic particles 26 may differ in size. In instances where hollow spheres are utilized, the wall thickness of the spheres may be tuned to provide the desired echogenicity.

In one example, glass, polymer, ceramic, metal, or the like hollow microspheres may be used. Using hollow spheres may help to maintain a favorable (e.g. low) weight. Such materials/spheres may be utilized when forming tube 12′ via an extrusion, molding, and/or the like. In addition or in the alternative, such materials may be used with dip coatings. Either way, the microspheres (e.g., hollow microspheres) may increase the echoic behavior under ultrasound viewing.

In another example, salt such as sodium chloride may be disposed within the resin 24 (e.g., via subfusion), for example during an extrusion process, in order to produce intentional air pockets. Such air pockets may increase the echoic behavior of the shaft 12′.

In some instances, an additional lumen may be incorporated into the tube 12′, for example in an extrusion process, that can form/include air pockets. Such additional lumens may be sufficiently small to fit into the tube wall and, generally, would not be used to pass another device therethrough but rather would be used for air pockets to increase echoic behavior. Similarly, nanotubes such as carbon nanotubes may be incorporated into molded or dipped parts. Such nanotubes may be randomly oriented to increase reflectance properties and/or increase echoic behavior. In some cases, woven or multilayer structures (e.g., which may include carbon fiber) may incorporated into the tube 12′. Such woven structures may have localized density variations and/or structural geometries, which may enhance echogenicity.

As indicated herein, forming the tube 12′ may include a suitable process. For example, the resin 24 and echogenic particles 26 may be combined/mixed. The ratio or relative amount/number of echogenic particles 26 to resin material may be varied or tuned in order to provide the desired echogenicity. The mixed resin 24 and echogenic particles 26 may be formed into the tube 12′ by an extrusion process, molding process, casting process, and/or other suitable processes. The resin 24 may include a suitable material or materials such as those disclosed herein. For example, the resin 24 may include polyether ether ketone (e.g., VICTREX 650g), nylon (e.g., GRIVORY 21), polyethylene, high-density polyethylene, fluoropolymers (e.g., polytetrafluoroethylene), polymethyl methacrylate, polyether sulfone, polyether block amide, polyether-ester, combinations thereof, and/or the like. In some instances, the resin 24 may also have other materials or particles 28 therein. For example, radiopaque particles 28 may be disposed within the resin 24. In some of these and in other instances, radiopaque fillers can be added/compounded with the resin 24, for example, to increase the fluoroscopic visualization characteristics.

In some instances, the echogenic particles 26 may be disposed along an entire length of the shaft 12′. Alternatively, the echogenic particles 26 may be disposed along one or more discrete lengths or regions of the shaft 12′. In examples where the echogenic particles 26 are disposed along one or more discrete lengths or regions of the shaft 12′, echo transparent regions (e.g., regions transparent to ultrasound) may be disposed between the echoic region (e.g., including the echogenic particles 26). This may allow regions of the shaft 12′ to be arranged and/or used akin to an echogenic ruler for taking measurements within a patient.

Rather than being formed as a tube or shaft 12′, the echogenic particles may be incorporated into relatively short sleeves or bands that can be applied to a medical device in order to enhance echogenicity. For example, echogenic bands, which may be similar in form to typical radiopaque marker bands, may be incorporated into a variety of medical devices in order to enhance echogenicity.

The echogenic particles 26 may be configured to enhance echogenicity, for example, by encouraging the scatter of ultrasound energy in a manner similar to air pockets (e.g., air pockets within dimpled features), laser cuts, markings, etc. For example, as schematically shown in FIG. 5, the shaft 12′ may have desirable echogenicity as represented by solid lines.

FIGS. 6-7 illustrate a portion of another example medical device 112, which may be similar in form and function to other devices disclosed herein. In this example, the medical device 112 may take the form of a tube that includes an inner layer 130, an outer layer 132, and a textured or undulating member 134 disposed between the inner layer and the outer layer 132. The undulating member 134 may include a plurality of axially-extending and/or radially-extending undulations or waves. The shape/arrangement of the undulating member 134 within the medical device 112 may form or define one or more air pockets 136 within the medical device 112 (e.g., within the wall of the medical device 112). The air pockets 136 may enhance the echogenicity of the medical device 112.

In some of these and in other instances, the undulating member 134 may include a porous material, for example disposed between the inner and outer layers 130, 132. The porous material/layer, which may or may not include undulations, may include a suitable material such as expanded polytetrafluoroethylene. In some of these and in other instances, the inner and outer layers 130, 132 may include materials such as those disclosed herein such as polyetheretherketone.

As indicated herein, it may be desirable to incorporate echoic properties into a wide variety of different medical devices. A few example applications are disclosed in FIGS. 8-10. Other applications are contemplated. For example, FIG. 8 illustrates a portion of another example medical device 240, which may be similar in form and function to other devices disclosed herein. In this example, the medical device 240 may be a balloon catheter. The balloon catheter may include a catheter shaft 242 including an outer shaft 244 and an inner shaft 246. A balloon 248 may be coupled to the catheter shaft 242. One or more echogenic members may be coupled to the medical device 240. For example, an echogenic member 252 may be coupled to the balloon 248 and/or the catheter shaft 242. The echogenic member 252 may take the form of a sleeve or covering disposed along discrete portions of the balloon catheter. For example, the echogenic member 252 may be disposed along the proximal waist 250 of the balloon 248 and/or the outer shaft 244. In some of these and in other instances, an echogenic member 254 may be coupled to the balloon 248 and/or the catheter shaft 242. For example, the echogenic member 254 may be disposed along the distal waist 251 of the balloon 248 and/or the inner shaft 246. The echogenic members 252 may be structural similar to other echogenic structures disclosed herein. For example, the echogenic member 252 may include echogenic particles.

FIG. 9 illustrates a portion of another example medical device 340, which may be similar in form and function to other devices disclosed herein. In this example, the medical device 340 may be a basket or snare device. The basket device may include a basket 356. One or more echogenic members may be coupled to the medical device 340. For example, an echogenic member 358 may be disposed at the distal end of the basket 356. In some of these and in other instances, an echogenic member 360 may be disposed at the proximal end of the basket 356. The echogenic members 352 may be structural similar to other echogenic structures disclosed herein. For example, the echogenic member 352 may include echogenic particles.

FIG. 10 illustrates a portion of another example medical device 440, which may be similar in form and function to other devices disclosed herein. In this example, the medical device 440 may be a stent. The stent may include one or more struts 446. One or more echogenic members may be coupled to the medical device 440. For example, an echogenic member 448 may be disposed along the struts 446. In some instances, the struts 446 may include echogenic particles therein. In some of these and in other instances, the struts 446 may include a covering or coating (e.g., dip coating) that is configured to enhance the echogenicity of the medical device 440.

The materials that can be used for the various components of the system 10 (and/or other systems disclosed herein) may include those commonly associated with medical devices. For simplicity purposes, the following discussion makes reference to the shaft 12 and other components of the system 10. 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.