Patent Description:
Pancreatic cancer is the third-leading cause of cancer death in the United States. Approximately twenty to thirty percent of pancreatic cancers originate from mucinous type pancreatic cysts, which are found in two percent of Americans and become increasingly prevalent with age.

Because cyst disruption can accelerate the spread of the disease, commonly cysts are monitored using non-invasive imaging techniques, such as Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) to categorize and monitor cyst development. Imaging may be repeated on a regular basis (such as every six months). While imaging is less invasive, it provides an inexact diagnosis which may increase patient anxiety and delay diagnosis.

Endoscopic ultrasound (EUS) is a procedure used to diagnose and evaluate pancreatic cysts. In this procedure, an endoscopic ultrasound is advanced through a patient's mouth into the stomach and duodenum, from where it can image the pancreas. A needle may be used to aspirate fluid from the cyst for biopsy purposes. While such techniques are effective for diagnosis purposes, a high recurrence of cysts, particularly in prior, aspirated cyst locations, is common and may increase the frequency and number of biopsy procedures. It would be desirable to identify a less invasive device and method for cyst categorization, diagnosis, and treatment with improved accuracy.

<CIT> and <CIT> disclose different devices for treating Gastro-Esophageal Reflux Disease ("GERD"). <CIT> discloses a device for resection of malignant and pre-malignant lesions and/or tumors within the gastrointestinal tract.

The device according to the invention is defined in claim <NUM>. Although methods of operation are not explicitly recited by the wording of the claims, they are considered useful for understanding the invention.

According to one aspect of the present disclosure, a device (such as, but limited to, a device for draining cysts) includes a catheter having a proximal end, a distal end, a lumen extending from the proximal end to the distal end; and a sheath disposed about the distal end of the catheter, wherein a distal tip of the sheath extends beyond the distal end of the catheter to form a chamber distally of the distal end of the catheter. The device includes an absorbent material disposed within the chamber of the sheath, a handle coupled to the sheath and including a release or deployment mechanism ("release" mechanism herein for the sake of convenience and without intent to limit) configured and positioned to release the absorbent material from the chamber, and a vacuum passage disposed for application of a proximal suction force through the catheter lumen.

The handle of the device according to the invention includes the vacuum source, or the handle is coupled to the vacuum source. The handle may include a housing having a bore extending from a proximal opening of the housing to a distal inlet of the housing, where the proximal end of the catheter is fluidly coupled to the distal inlet of the housing. In one embodiment, the vacuum source includes a plunger rod translatably disposed within the bore, the plunger rod including a plunger translatable within the bore, where proximal advancement of the plunger rod and the plunger through the bore increases a pressure within the housing and the lumen of the catheter to generate the proximal suction force. In some embodiments, the release mechanism includes one of a knob, a switch, a thumbwheel, a button, a dial, or a combination thereof. In various embodiments the absorbent material includes foam. The foam may be bioabsorbable, formed from a radiolucent or echogenic material, be a drug eluting foam, or a combination thereof. In one embodiment, the catheter of the device may be shaped and configured for translation through a working channel of an endoscope. In one embodiment the catheter may be shaped and configured for translation through a needle lumen of a needle catheter.

According to another aspect of the present disclosure, a catheter system includes a catheter having a proximal end, a distal end, and a catheter lumen extending from the proximal end to the distal end; and a sheath disposed about the distal end of the catheter, the sheath having a distal tip that extends distally beyond the distal end of the catheter to form a chamber distally of the distal end of the catheter. The catheter system includes an absorbent material having a compressed configuration sized to fit within the chamber of the sheath, and an expanded configuration larger than the compressed configuration, the absorbent material including a radiolucent material, an echogenic material, a drug eluting material, a bioabsorbable material, or a combination thereof. The catheter system includes a handle coupled to the sheath and including a release mechanism configured and positioned to release the absorbent material from the chamber, and a vacuum passage disposed for application of a proximal suction force through the catheter lumen.

In various embodiments, the release mechanism configured and positioned to release the absorbent material may include a knob, a switch, a thumbwheel, a button, a dial, or a combination thereof. The catheter system may further include a housing having a bore extending from a proximal opening of the housing to a distal inlet of the housing, where the distal inlet is fluidly coupled to the proximal end of the catheter. The vacuum source may include a plunger rod translatably disposed within the bore, the plunger rod including a plunger translatable within the bore, where proximal advancement of the plunger rod and the plunger through the bore decreases a pressure within the housing and the catheter lumen to generate the proximal suction force. The catheter may be shaped and configured for translation through a working channel of an endoscope, a lumen of a needle catheter, or both.

According to a further aspect of the present disclosure, a method includes advancing a catheter through a body lumen into a cyst, the catheter having a proximal end, a distal end, and a catheter lumen extending therethrough, the catheter including an elongate body disposed within a sheath, the sheath extending distally from the distal end of the catheter to form a chamber having an absorbent material stored therein. The method includes releasing the absorbent material from the chamber of the sheath into the cyst, applying a proximal suction force through the catheter lumen to reduce the cyst and to compress the absorbent material within the cyst, and removing the catheter from the cyst and the body lumen.

In various embodiments, the catheter includes a proximal handle including a housing having a bore extending from a proximal opening of the housing to a distal inlet of the housing, where the distal inlet of the housing is fluidly coupled to the proximal end of the catheter, a plunger rod translatably disposed within the bore, the plunger rod including a plunger translatable within the bore. The method includes applying the proximal suction force including proximally withdrawing the plunger rod and the plunger through the bore to generate the proximal suction force through the distal inlet and the catheter. In some embodiments, the method includes advancing the catheter through the working channel of an endoscope to the cyst. In some embodiments, the method includes advancing the catheter through a needle lumen of a needle catheter to the cyst. In some embodiments, the method includes draining the cyst using the needle catheter prior to inserting and advancing the catheter through the needle catheter, and where applying the proximal suction force through the catheter lumen uses a needle aspiration suction force.

The foregoing and other features of the present disclosure will become more fully apparent from the following description and appended claims, taken in conjunction with the accompanying drawings. Understanding that these drawings depict only several embodiments in accordance with the disclosure and are not to be considered limiting of its scope, the disclosure will be described with additional specificity and detail through use of the accompanying drawings. In the following detailed description, reference is made to the accompanying drawings, which form a part hereof. In the drawings, similar symbols typically identify similar components, unless context dictates otherwise. The illustrative embodiments described in the detailed description and drawings are not meant to be limiting. Other embodiments may be utilized, and other changes may be made, without departing from the scope of the subject matter presented here. It will be readily understood that the aspects of the present disclosure, as generally described herein, and illustrated in the drawing, can be arranged, substituted, combined, and designed in a wide variety of different configurations.

A device such as for managing cysts includes a catheter system shaped and configured to deploy an absorbent material, including but not limited to a foam, such as into a cyst. The absorbent material advantageously absorbs fluid (e.g., contained within a cyst), for example fluid that may remain following aspiration, reducing the potential for cyst recurrence. In various embodiments, the absorbent material may be bioabsorbable, radiolucent, echogenic, drug eluting, or a combination thereof.

The device further includes or is coupled to a vacuum source which applies negative pressure to the cyst during and/or following foam delivery for drainage of the cyst, thereby reducing the overall size and/or profile of the cyst. Reducing the overall profile of the cyst may decrease the potential for cyst recurrence. In addition, reducing the overall profile may increase contact between the foam and the cyst sidewalls. In embodiments where the foam is coated with or otherwise incorporates drugs for localized therapy of the cyst, applying such vacuum pressure may increase treatment efficacy.

Various embodiments of such a device and method of cyst management will now be described. Reference in this specification to "one embodiment," "an embodiment," or "in some embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. The appearances of the phrases "one embodiment," "an embodiment," or "in some embodiments" in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments necessarily mutually exclusive of other embodiments. Similarly, various requirements are described which may be requirements for some embodiments but may not be requirements for other embodiments.

As used herein, the term "distal" refers to the end farthest away from the medical professional when introducing a medical device into a patient, while the term "proximal" refers to the end closest to the medical professional when introducing a medical device into a patient. A central axis means, with respect to an opening, a line that bisects a center point of the opening, extending longitudinally along the length of the opening when the opening comprises, for example, a tubular frame, a strut, or a bore.

<FIG> illustrates an example of a catheter system <NUM> including a handle <NUM> coupled to a catheter <NUM>. The catheter <NUM>, in one embodiment, comprises an elongate body <NUM> having a proximal end <NUM> releasably coupled to the handle <NUM> (for example, screwed on via knob <NUM>) and a distal end <NUM>. In one embodiment, the catheter may comprise a composite of layers of thermoplastic elastomer (TPE). Alternatively, nylon, polyurethanes, polyester, silicone, or other similar materials may be used to provide thin walls that may be extruded and layered over braided wires or coils for tensile and hoop strength, although the disclosed system is not limited to any particular material composition.

According to one embodiment, the catheter system is shaped and configured for management of pancreatic cysts, although the disclosure is not limited to use in the pancreas, and it is appreciated that the principles disclosed herein may be extended by one of skill in the art to cyst management throughout a body.

However, for embodiments wherein the catheter is shaped and configured for pancreatic cyst management, the length of the catheter <NUM> may be selected to enable the catheter to be transluminally navigated through the gastrointestinal tract to the pancreas. For example, the length of the catheter may range from at least about <NUM> millimeters (mm) to about <NUM>, such as between about <NUM> and <NUM>, or between about <NUM> and <NUM> or the like.

In one embodiment, the catheter <NUM> may comprise a sheath <NUM>, disposed over the elongate body of the catheter <NUM>. Similar to the elongate body, the sheath may be comprised of a thermoplastic elastomer, nylon, polyurethane, polyester, silicone, or other similar materials. In one embodiment, the sheath <NUM> may have a distal end <NUM> that extends past the distal end <NUM> of the elongate body <NUM>, forming a chamber inside the distal end <NUM> of the sheath, wherein an absorbent material (such as foam) may be disposed for delivery to a cyst treatment site. In some embodiments, the distal end <NUM> may include one or more echogenic features <NUM>, facilitating visualization of the distal end <NUM> during ultrasound.

Outer diameters of the elongate body <NUM> and/or sheath <NUM> are selected to enable the catheter to be advanced freely within a working channel of an endoscope. For example, in various embodiments the outer diameter of the elongate body <NUM> and/or sheath <NUM> may be at least about <NUM> and at most about <NUM>, such to fit and be extendible within an endoscope working channel (for example, a working channel having a <NUM> diameter) although the disclosure is not so limited.

In some embodiments, the sheath <NUM> and elongate body <NUM> may be translatably disposed relative to each other to enable release of the foam from the distal end <NUM> of the sheath <NUM>. For example, in some embodiments, the sheath may be shaped and configured to be withdrawn proximally of the distal end <NUM> of the elongate body <NUM> of the catheter <NUM>, or the elongate body <NUM> may be disposed to move proximally within the sheath <NUM>.

In other embodiments, the sheath <NUM> and elongate body <NUM> may be fixedly disposed relative to each other, and the elongate body may comprise a suitable release mechanism (e.g., a push rod or the like) configured and positioned to release and / or expel and / or deploy (hereinafter "release" for the sake of convenience, without intent to limit) the sheathed foam from the distal end <NUM> of the sheath. Various embodiments of release mechanisms known to those of ordinary skill in the art as configured and positioned to release a material, such as the absorbable material from the distal end <NUM> of the sheath <NUM>, at a desired site are considered within the scope of this disclosure. For example, any of the following release mechanisms may be used: a pneumatic-assisted mechanism to release foam/powder/gel; a mechanical structure (e.g., screw mechanism, plunger (push) mechanism etc.) to release foam/powder/gel; a release foam (by changing state of foam/powder/gel).

A lumen <NUM> (<FIG>) extends from the proximal end <NUM> of the elongate body <NUM> of the catheter <NUM> through the distal end <NUM> of the sheath. The lumen <NUM> provides a fluid flow pathway between the distal end <NUM> and a vacuum source associated with the handle <NUM>, enabling proximal fluid suction through the catheter <NUM> during a cyst management process as disclosed below.

The handle <NUM> includes a housing <NUM> having a bore <NUM> (<FIG>) extending therethrough. In one embodiment, a vacuum cylinder <NUM> is adjustably disposed within the proximal portion of the handle housing bore and a distal inlet port <NUM> is disposed at a distal end of the bore of the housing <NUM>. In one embodiment, the housing <NUM> may include a tab lock <NUM> that may be used to control an adjustment height, and concomitantly an available vacuum force, provided by the vacuum cylinder <NUM>. The distal inlet port <NUM> fluidly couples the lumen <NUM> of the catheter <NUM> to the bore <NUM> of the housing <NUM>.

In one embodiment, a plunger rod <NUM> is translatably disposed within the vacuum cylinder <NUM>, wherein the plunger rod <NUM> includes a distal plunger <NUM> that seals the proximal end of the bore against air inflow from outside the housing <NUM>. As a result, proximal translation of the plunger rod <NUM> within the vacuum cylinder <NUM> creates a negative pressure within the bore of the housing <NUM>, providing a proximal vacuum/suction force through the distal inlet <NUM> of the housing that draws fluid (e.g., gas and/or liquid) through the lumen <NUM> of the catheter <NUM>.

In some embodiments, the handle <NUM> may also comprise release mechanisms configured and positioned to control delivery of the absorbent material to the cyst. For example, a dial <NUM> is shown disposed about the vacuum cylinder <NUM> of the handle <NUM>. In one embodiment, rotation of the dial may control a release mechanism internal to the handle/catheter, that is configured and positioned to release the absorbent material from the distal end <NUM> of the catheter sheath <NUM>. It is appreciated that any of a variety of release mechanisms may be used to manage the release of the absorbent material, and other release mechanisms, such as switches, knobs, buttons, thumbwheels, and the like are considered to be within the scope of this disclosure.

<FIG> illustrates one embodiment of an absorbent material <NUM> that may be disposed within the chamber at the distal end <NUM> of the sheath <NUM> and used as disclosed herein. In one embodiment, the absorbent material <NUM> may comprise a foam or gel or powder or similar material having the ability to absorb and retain biological fluid from the cyst, including but not limited to blood, mucus, and other bodily fluids. The foam may be an open cell foam for promoting drainage. According to one aspect, it is appreciated that deploying foam into the cyst to absorb excess fluids may reduce the recurrence of a cyst in that location. Examples of foams that may be suitable for such purpose include those having hemostatic properties, such as those formed from of porcine gelatin (e.g. the GelForm™ Sponge, manufactured by Pharmacia, of Kalamazoo, MI, or Surgifoam™ Sponge, manufactured by Ethicon, of Somerville, NJ), those comprised of bovine collagen (e.g. Ultrafoam™, manufactured by Integra, of Plainsboro, NJ, Helistat, manufactured by Ethicon/J&J of Somerville, NJ), those composed of oxidized regenerated cellulose (ORC) (e.g., Surgicel Oxycel, manufactured by Ethicon/J&J) and the like or a combination thereof. Although the absorbent material <NUM> of <FIG> is shown having a generally cylinder shape, the present disclosure is not limited to a foam having any particular shape and/or size. It is appreciated that the amount of foam delivered to a cyst is dependent upon the size of the cyst cavity, and it is anticipated that the amount of foam disposed within the distal end <NUM> of the sheath <NUM> may store foam sufficient to treat multiple cysts. In various embodiments foam may be stored in a compressed form having a smaller volume than in a delivered form, which may be an expanded form, when the foam is outside of the sheath <NUM>. In various embodiments, foam may take on substantially the same volume, shape, and/or form within the sheath <NUM> and when delivered outside of the sheath <NUM>. By way of example, sufficient foam may be stored to treat more than one cyst, or a cyst requiring a foam larger than the foam provided. The foam may be provided in one or more cartridges and deployed depending on cyst size and / or the number of cysts. It will be appreciated that the foam need not be stored in the catheter. Instead (or in addition) the foam can be loaded through the handle <NUM> (such as by syringe) or through the distal end <NUM> of the catheter <NUM>.

In some embodiments, the foam may comprise additional characteristics, in addition to properties of absorption. For example, in one embodiment, the foam may be a soft, resilient hemostatic bio foam capable of conforming to the cyst cavity and transitioning to a porous gel or other substance that may be absorbed by the body over time. In some embodiments, the foam may be coated by, or otherwise incorporate, therapeutic agents that accelerate healing of the cyst, and/or provide localized treatment, including cancer treatment, such as any therapeutic agents having properties to delay generation of fluid or to delay conversion of a cyst to malignant tissue, or any drug or drugs (known or to be developed) having healing properties. In some embodiments, the foam may be marked with or formed from substances increasing visibility of the treated cyst cavity during subsequent foam placement and subsequent imaging, for example, including radiolucent or echogenic markers or the like.

<FIG> is a cross-sectional view of the catheter system <NUM>, showing a distal portion of catheter <NUM>, and the handle <NUM>. In <FIG>, the foam <NUM> is visible within the distal end <NUM> of the catheter <NUM>, disposed within a chamber <NUM> extending between the distal end <NUM> of the elongate body <NUM> of the catheter <NUM> and the distal end <NUM> of the sheath <NUM>. A push rod <NUM> is positioned with a distal end <NUM> thereof adjacent to the chamber <NUM>, and extends axially within the lumen <NUM> of the elongate body <NUM>, from adjacent the chamber <NUM>, through the distal inlet <NUM> of the handle housing <NUM> and into the housing <NUM> to a proximal end <NUM> of the push rod <NUM> positioned adjacent the release mechanism (e.g., dial) <NUM>. Distal advancement of the push rod <NUM> by actuation of release mechanism <NUM> expels the foam <NUM> through the distal end <NUM> of the sheath <NUM>.

An example of a vacuum source in the form of a plunger rod and plunger is illustrated in <FIG>. A vacuum cylinder <NUM> is shown disposed within the bore <NUM> of the housing <NUM> and a plunger rod <NUM> is shown axially disposed within the vacuum cylinder <NUM>. A plunger <NUM>, disposed on the distal end of the plunger rod <NUM>, may be formed of rubber or other material that enables the plunger rod <NUM> to move axially within the vacuum cylinder <NUM> without allowing external airflow into the bore <NUM>. In various embodiments, a lumen (e.g., lumen <NUM> of <FIG>) may be in fluid communication with a vacuum source (e.g., at a proximal end of the system <NUM>).

According to one aspect, the catheter system <NUM> may be used as part of an Endoscopic Ultrasound (EUS) procedure for pancreatic cyst management. <FIG> illustrates one embodiment of an ultrasound endoscope <NUM> including a handle <NUM> and a steerable catheter <NUM> having an ultrasound transducer <NUM> disposed at its distal end. Various working channels may be disposed within the catheter <NUM>, and instruments may access the working channels using one or more of the ports <NUM> disposed within the handle. Dials <NUM> of the handle <NUM> may be used to navigate a distal end <NUM> of the catheter <NUM> to a treatment site, e.g., to a cyst. <FIG> illustrates an aspiration needle <NUM>, that has been disposed through a working channel of the endoscope <NUM> and deployed to aspirate fluid from a cyst.

<FIG> are cross-sectional illustrations of a distal end of the endoscope <NUM>, during a procedure, for example during cyst management. In <FIG>, an aspiration needle system <NUM>, including a distal aspiration needle <NUM>, has been forwarded distally through the working channel <NUM> of the catheter <NUM> of the endoscope. The needle <NUM> extends distally adjacent to the ultrasound transducer <NUM>, enabling visualization of the aspiration procedure.

Following aspiration, the aspiration needle system <NUM> may be withdrawn from the working channel <NUM> while the endoscope is kept in position, and, as shown in <FIG>, the catheter <NUM> of the catheter system <NUM> may be advanced through the working channel <NUM> of the steerable catheter <NUM> to the aspirated cyst. Visualization of the distal end <NUM> of the catheter <NUM> is facilitated using the echogenic markers <NUM>, which may be visualized using the ultrasound transducer <NUM>.

<FIG> are cross-sectional illustrations of a distal end of the endoscope <NUM>, for example during another embodiment of a procedure such as cyst management. As in <FIG>, in <FIG> an aspiration needle system <NUM>, including a distal aspiration needle <NUM> has been forwarded down the working channel <NUM> of the catheter <NUM> of the endoscope <NUM>. The needle <NUM> extends distally adjacent to the ultrasound transducer <NUM>, enabling visualization of the aspiration procedure. In <FIG>, the needle lumen <NUM>, defining the aspiration path, is visible.

In <FIG>, following aspiration, the aspiration needle system <NUM> remains in place in the working channel <NUM>, and the catheter <NUM> of the catheter system <NUM> may be advanced through the needle lumen <NUM> of the needle system <NUM> to the aspirated cyst. Accordingly, the catheter system may be advanced towards a cyst, and visualized, using a variety of available paths within the ultrasound endoscope.

<FIG> illustrate an example of a process for cyst management utilizing the catheter system <NUM> described above.

In <FIG>, the endoscope <NUM> may be advanced to a target position proximate a cyst <NUM> in the pancreas <NUM>, for example along a gastrointestinal tract. Visualization of the environment and targeting of the cyst may be facilitated using the ultrasound transducer <NUM>. An aspiration needle <NUM> may be advanced from the working channel of the endoscope <NUM> into the cyst <NUM> to drain cyst fluid.

As shown in <FIG>, following draining of cyst fluid, in one embodiment the needle is withdrawn and the distal end <NUM> of the catheter <NUM> may be advanced through the endoscope <NUM> towards the cyst <NUM>.

As shown in <FIG>, following advancement of the distal end <NUM> of the catheter <NUM> to the cyst <NUM>, the foam <NUM> may be released into the cyst <NUM>. In one embodiment, prior to, during and/or after release of the foam <NUM> into the cyst <NUM>, a proximal vacuum force draws the walls of the cyst and/or the foam towards the distal end <NUM> of the catheter <NUM>, reducing the size of the cyst.

Following administration of the foam, in <FIG>, the endoscope may be removed from the gastrointestinal tract, and/or positioned to treat a different cyst. The cyst <NUM> remains, in reduced form with added foam <NUM>, which continues to absorb cyst fluid over time, reducing cyst recurrence.

It should be noted that although the catheter system and method of use has been described as part of a transluminal procedure, other methods of access, including laparoscopic, percutaneous, and/or using endoscopic retrograde cholangiopancreatography may similarly benefit from the concepts disclosed herein.

Accordingly, a catheter system and method of use thereof has been shown and described. Various modifications to the implementations described in this disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other implementations without departing from the scope of this disclosure. Thus, the disclosure is not intended to be limited to the implementations shown herein but is to be accorded the widest scope defined in the claims. The word "example" is used exclusively herein to mean "serving as an example, instance, or illustration. " Any implementation described herein as "example" is not necessarily to be construed as preferred or advantageous over other implementations, unless otherwise stated.

Certain features that are described in this specification in the context of separate implementations also can be implemented in combination in a single implementation. Conversely, various features that are described in the context of a single implementation also can be implemented in multiple implementations separately or in any suitable sub-combination.

Claim 1:
A device (<NUM>) comprising:
a catheter (<NUM>) having a proximal end (<NUM>), a distal end (<NUM>), and a lumen (<NUM>) extending from the proximal end to the distal end;
a sheath (<NUM>) disposed about the distal end of the catheter and having a distal tip (<NUM>) that extends distally beyond the distal end of the catheter to form a chamber (<NUM>) within the sheath distally of the distal end of the catheter;
an absorbent material (<NUM>) disposed within the chamber of the sheath;
a handle (<NUM>) coupled to the sheath and including a release mechanism (<NUM>) configured and positioned to release the absorbent material from the chamber; and
a vacuum passage (<NUM>) disposed for application of a proximal suction force through the catheter lumen,
wherein the lumen (<NUM>) of the catheter forms the vacuum passage and provides a fluid pathway between a distal end (<NUM>) of the sheath (<NUM>) and a vacuum source that is included in or can be coupled to the handle.