Patent Description:
The present disclosure pertains to medical devices, and methods for manufacturing medical devices. More particularly, the present disclosure pertains to medical devices for imaging.

A wide variety of intracorporeal medical devices have been developed for medical use, for example, intravascular use. Some of these devices include guidewires, catheters, and the like. These devices are manufactured by any one of a variety of different manufacturing methods and may be used according to any one of a variety of methods. Of the known medical devices and methods, each has certain advantages and disadvantages. There is an ongoing need to provide alternative medical devices as well as alternative methods for manufacturing and using medical devices.

<CIT> relates to medical probes having an inner fluidic path for flowing an internal liquid therein, in which at least one internal surface in flow communication with the inner fluidic path is hydrophilic for the reduction of bubble adhesion thereto. Imaging probes are described, in which an internal surface in flow communication with an internal fluidic path, and through which imaging energy propagates, is coated with a hydrophilic layer that has a thickness and/or an acoustic impedance for reducing an impedance mismatch. Various configurations are described, including embodiments in which hydrophobic bubble trapping surface regions are included in addition to the hydrophilic surface regions. In some embodiments, a medical probe may have an inner lumen defined by an inner fluidic conduit, where at least a portion of the inner surface of the inner fluidic conduit is hydrophilic.

<CIT> relates to an ultrasonic probe constituted so that a flexible wire, a vibrator holder connected to the flexible wire and an ultrasonic vibrator held by the vibrator holder are covered with a sheath. An acoustic window is provided at the vicinal position of the echo path of the ultrasonic vibrator in the sheath. Further, a means excluding air bubbles stagnated in the vicinity of the ultrasonic vibrator (or reflecting plate) in the probe is provided.

<CIT> relates to an imaging probe for use in a catheter for ultrasonic imaging. The catheter may be of the type including a sheath having an opening at a distal end for conducting a fluid there through. The imaging probe includes a distal housing coupled to a drive shaft for rotation, a transducer within the distal housing for generating and sensing ultrasonic waves, and a fluid flow promoter that promotes flow of the fluid within the sheath across the transducer.

This disclosure provides design, material, manufacturing method, and use alternatives for medical devices. An imaging medical device is disclosed. The imaging medical device comprises: an elongate shaft having a distal end region; an imaging assembly disposed within the elongate shaft, the imaging assembly including a drive cable, a housing coupled to the drive cable, and a transducer coupled to the housing; and a bubble-reducing member disposed adjacent to the drive cable.

Alternatively or additionally to any of the embodiments above, the imaging assembly is rotatable within the elongate shaft.

Alternatively or additionally to any of the embodiments above, the imaging assembly is translatable within the elongate shaft.

Alternatively or additionally to any of the embodiments above, the bubble-reducing member is coupled to the drive cable.

Alternatively or additionally to any of the embodiments above, the bubble-reducing member extends between the drive cable and an inner surface of the elongate shaft.

Additionally, the bubble-reducing member includes a barrier disk with a plurality of openings formed therein.

Alternatively , not forming part of the present invention, the bubble-reducing member includes a tapered mesh.

Alternatively , not forming part of the present invention, the bubble-reducing member includes a plurality of axially-extending fingers.

Alternatively or additionally to any of the embodiments above, the bubble-reducing member includes a region with a surface treatment.

Alternatively or additionally to any of the embodiments above, the bubble-reducing member includes a coating.

Alternatively or additionally to any of the embodiments above, the transducer includes an ultrasound transducer.

An imaging medical device is disclosed. The imaging medical device comprises: a catheter having a proximal end region and a distal end region; an imaging assembly movably disposed within the catheter, the imaging assembly including a drive cable, a housing coupled to the drive cable, and an ultrasound transducer coupled to the housing; and a bubble-reducing member coupled to the drive cable, the bubble-reducing member being configured to allow fluid to flow between the proximal end region to the distal end region while disrupting the flow of bubbles between the proximal end region and the distal end region.

Alternatively or additionally to any of the embodiments above, the imaging assembly is rotatable within the catheter.

Alternatively or additionally to any of the embodiments above, the imaging assembly is axially translatable within the catheter.

Alternatively or additionally to any of the embodiments above, the bubble-reducing member extends between the drive cable and an inner surface of the catheter.

Alternatively or additionally to any of the embodiments above, the bubble-reducing member includes a hydrophobic region.

An imaging medical device is disclosed. The imaging medical device comprises: a catheter having a proximal end region and a distal end region; an imaging assembly disposed within the catheter, the imaging assembly being rotatable and translatable relative to the catheter and including a drive cable, a housing coupled to the drive cable, and an ultrasound transducer coupled to the housing; and a bubble-reducing member coupled to the drive cable, the bubble-reducing member being configured to allow fluid to flow between the proximal end region to the distal end region while reducing the flow of bubbles between the proximal end region and the distal end region.

On the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the disclosure.

<FIG> is a side view of an example medical device <NUM>. In at least some instances, the medical device <NUM> takes the form of an imaging medical device. For example, the medical device <NUM> may be an intravascular ultrasound (IVUS) device that may be used to image a blood vessel. The structure/form of the medical device <NUM> can vary. In some instances, the medical device <NUM> may include an elongate shaft <NUM> having a proximal end region <NUM> and a distal end region <NUM>. A hub <NUM> may be coupled to or otherwise disposed adjacent to the proximal end region <NUM>. A tip member <NUM> may be coupled to or otherwise disposed adjacent to the distal end region <NUM>. The tip member <NUM> may include a guidewire lumen, an atraumatic distal end, one or more radiopaque markers, and/or other features. An imaging assembly <NUM> may be disposed within the shaft <NUM>. In general, the imaging assembly may be used to capture/generate images of a blood vessel. In some instances, the medical device may include devices and/or features similar to those disclosed in U. Patent Application Pub. No. <CIT> and U. Patent Application Pub. In at least some instances, the medical device <NUM> may resemble and/or include features that resemble the OPTICROSS™ Imaging Catheter, commercially available from BOSTON SCIENTIFIC, Marlborough, MA.

The imaging assembly <NUM> may include a drive cable or shaft <NUM>, a housing <NUM>, and an imaging member or transducer <NUM> coupled to the drive cable <NUM> and/or housing <NUM> as shown in <FIG>. In at least some instances, the transducer <NUM> includes an ultrasound transducer. Other transducers are also contemplated. The transducer <NUM> may be rotatable and/or axially translatable relative to the shaft <NUM>. For example, the drive cable <NUM> may be rotated and/or translated in order to rotate and/or translate the transducer <NUM> (and the housing <NUM>).

When using the medical device <NUM>, it may be desirable to prepare and/or flush the shaft <NUM>. In order to flush the medical device <NUM>, fluid may be infused at a flush port on or at the hub <NUM>. The fluid may exit the medical device at a vent hole (not shown) adjacent to the distal end of the housing <NUM>. In some instances, the flushing process may result in the formation of bubbles within the shaft <NUM>. It may be desirable to flush the medical device <NUM> in a manner that reduces the formation of bubbles and/or removes/disrupts any bubbles that are formed because bubbles may reflect/disrupt a signal (e.g., an ultrasound signal) from the transducer <NUM>, which disrupts the image. While flushing is generally effective for removing bubbles, some bubbles may still get caught within the shaft <NUM>. Disclosed herein are medical devices that are designed to help reduce the formation of bubbles and/or that are designed to help disrupt bubbles that may be formed within the medical device.

<FIG> illustrates a portion of another example medical device <NUM> that may be similar in form and function to other medical devices disclosed herein. The medical device <NUM> may include an elongate shaft <NUM>. An imaging assembly <NUM> may be disposed within the shaft <NUM>. The imaging assembly <NUM> may include a drive cable or shaft <NUM>, a housing <NUM>, and an imaging member or transducer <NUM> coupled to the drive cable <NUM> and/or housing <NUM>.

A bubble-reducing member <NUM> may be coupled to or otherwise disposed adjacent to the drive cable <NUM>. The bubble-reducing member <NUM> includes a barrier or annular portion <NUM>. A plurality of apertures <NUM> are disposed within the barrier portion <NUM> as can be seen in <FIG>. In <FIG>, the drive cable <NUM> is depicted schematically with cross-hatch. In general, the bubble-reducing member <NUM> is designed so that when the medical device <NUM> is flushed, the bubble-reducing member <NUM> blocks or reduces bubbles from travelling along the shaft <NUM> toward the housing <NUM> and transducer <NUM>. More particularly, the barrier portion <NUM> serves as a barrier to the flow of bubbles. In at least some instances, the bubble-reducing member <NUM> (e.g., the barrier portion <NUM>) extends between the outer surface <NUM> of the drive cable <NUM> and an inner surface <NUM> of the elongate shaft <NUM>. This may include the barrier portion <NUM> contacting the inner surface <NUM> of the shaft <NUM> or being disposed adjacent to the inner surface <NUM> of the shaft <NUM>.

The apertures <NUM> are designed to allow for fluid to pass therethrough. For example, the apertures <NUM> may be sized so that fluid can pass therethrough while bubbles are either prevented from passing therethrough or are disrupted/broken when passing therethrough in manner that reduces the impact of bubble on the generation of images. In other words, larger bubbles are substantially prevented from passing through the apertures <NUM> and only smaller bubbles (e.g., small enough so that they can readily escape the vent hole) can pass therethrough. For example, the apertures may have a diameter of about <NUM>-<NUM> (<NUM>-<NUM> inches), or about <NUM>-<NUM> (<NUM>-<NUM> inches). Bubbles passing through such apertures would be unlikely to adhere to the transducer <NUM> and/or otherwise be unlikely to impact the transducer <NUM>.

In some instances, the bubble-reducing member <NUM> may include a surface treatment and/or other structural feature that also helps to reduce bubbles. For example, the bubble-reducing member <NUM> may be surface treated, etched (e.g., chemically etched), treated/coated with a coating such as polytetrafluoroethylene, micropatterned, coated (e.g., including a coating), or otherwise made to be hydrophobic (e.g., super-hydrophobic). This may cause any bubbles formed to preferentially stick to the surface treated region rather than migrating toward the transducer <NUM>.

A bubble-reducing member <NUM> may be coupled to or otherwise disposed adjacent to the drive cable <NUM>. The bubble-reducing member <NUM> may take the form of a tapered mesh. The bubble-reducing member/tapered mesh <NUM> may function similarly to the bubble-reducing member <NUM>. For example, the bubble-reducing member <NUM> may extend between the outer surface <NUM> of the drive cable <NUM> and an inner surface <NUM> of the elongate shaft <NUM> so as to form a barrier while the mesh-like structure (e.g., with openings therein) allows for fluid to pass therethrough (while substantially preventing bubbles from passing therethrough).

A bubble-reducing member <NUM> may be coupled to or otherwise disposed adjacent to the drive cable <NUM>. The bubble-reducing member <NUM> may include a plurality of axially-extending fingers <NUM>. The bubble-reducing member <NUM> may function similarly to the bubble-reducing members <NUM>/<NUM>. For example, in at least some instances, the barrier member <NUM> extends between the outer surface <NUM> of the drive cable <NUM> and an inner surface <NUM> of the elongate shaft <NUM> so as to form a barrier. The spaces between the axially-extending fingers <NUM> allow for fluid to pass therethrough (while substantially preventing bubbles from passing therethrough).

The materials that can be used for the various components of the medical device <NUM> and/or other medical devices are disclosed herein. For simplicity purposes, the following discussion makes reference to the medical device <NUM>. 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 medical device <NUM> may be made from 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 (e.g., MARLEX® high-density polyethylene), low-density polyethylene (e.g., MARLEX® 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-<NUM> (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 <NUM> percent LCP.

Some examples of suitable metals and metal alloys include stainless steel, such as 304V, <NUM>, 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® <NUM>, UNS: N06022 such as HASTELLOY® C-<NUM>®, UNS: N10276 such as HASTELLOY® C276®, other HASTELLOY® alloys, and the like), nickel-copper alloys (e.g., UNS: N04400 such as MONEL® <NUM>, NICKELVAC® <NUM>, NICORROS® <NUM>, 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.

In at least some embodiments, portions or all of the medical device <NUM> may also be doped with, made of, or otherwise include a radiopaque material. Radiopaque materials are understood to be materials capable of producing a relatively bright image on a fluoroscopy screen or another imaging technique during a medical procedure. This relatively bright image aids the user of the medical device <NUM> in determining its location. Some examples of radiopaque materials can include, but are not limited to, gold, platinum, palladium, tantalum, tungsten alloy, polymer material loaded with a radiopaque filler, and the like. Additionally, other radiopaque marker bands and/or coils may also be incorporated into the design of the medical device <NUM> to achieve the same result.

In some embodiments, a degree of Magnetic Resonance Imaging (MRI) compatibility is imparted into the medical device <NUM>. For example, the medical device <NUM>, or portions thereof, may be made of a material that does not substantially distort the image and create substantial artifacts (e.g., gaps in the image). Certain ferromagnetic materials, for example, may not be suitable because they may create artifacts in an MRI image. The medical device <NUM>, or portions thereof, may also be made from a material that the MRI machine can image. Some materials that exhibit these characteristics include, for example, tungsten, cobalt-chromium-molybdenum alloys (e.g., UNS: R30003 such as ELGILOY®, PHYNOX®, and the like), nickel-cobalt-chromium-molybdenum alloys (e.g., UNS: R30035 such as MP35-N® and the like), nitinol, and the like, and others.

Claim 1:
An imaging medical device (<NUM>, <NUM>, <NUM>), comprising:
an elongate shaft (<NUM>, <NUM>, <NUM>) having a distal end region (<NUM>);
an imaging assembly (<NUM>, <NUM>, <NUM>) disposed within the elongate shaft, the imaging assembly including a drive cable (<NUM>, <NUM>, <NUM>), a housing (<NUM>, <NUM>, <NUM>) coupled to the drive cable, and a transducer (<NUM>, <NUM>, <NUM>) coupled to the housing; and
a bubble-reducing member (<NUM>, <NUM>, <NUM>) disposed adjacent to the drive cable,
characterized in that
the bubble-reducing member (<NUM>) includes a barrier disk (<NUM>) with a plurality of openings (<NUM>) formed therein.