Patent ID: 12208219

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 disclosure 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 in 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.

A number of medical procedures, including intravascular procedures, procedures along the digestive and/or biliary tract, thoracic procedures, etc. utilize medical devices to access tissue intended for removal (e.g., “target tissue”) within the body. For example, in some current medical procedures (e.g., Endoscopic Submucosal Dissection (ESD), Peroral Endoscopic Myotomy (POEM), cholecystectomy, Video-Assisted Thoracoscopic Surgery (VATS)), physicians may utilize an endoscope or similar medical device to access and remove cancerous lesions. Further, as part of the procedure, the physician may utilize an endoscope capable of both accessing the target tissue site while also permitting a cutting device to be deployed therethrough to excise the target tissue. Additionally, in some instances, the endoscope may incorporate features which assist the physician in visualizing and performing the tissue dissection procedure. For example, some endoscopes may include a light and/or camera designed to illuminate the body lumen as the scope is navigated and positioned adjacent to the target tissue site. Additionally, some endoscopes may also include a lumen (e.g., a working channel) through which a cutting member or other accessory medical devices may be deployed and utilized.

While physicians are becoming more proficient at extracting cancerous lesions from within the body (e.g., within the digestive tract, abdominal cavity, thoracic cavity, etc.), the extraction methods continue to be inefficient and time-consuming. For example, in some instances poor visualization of the tissue dissection process may result in a prolonged tissue dissection procedure. In another example, the actual tissue that the physician is attempting to dissect may, itself, obstruct the pathway of the tools which the physician is using during the procedure. Therefore, in some instances it may be desirable to utilize a medical device which assists in improving the visualization of the target tissue while also mitigating the obstruction of dissection tools the physician is utilizing. Therefore, in some instances it may be desirable to utilize a tissue retraction device which lifts and retracts the region of tissue to be dissected by the physician. Disclosed herein are medical devices such as a tissue retraction device and delivery system that are designed to lift and retract the target tissue.

FIG.1is a partial cross-sectional side view of an example tissue retraction delivery system10including a distal portion12and a proximal portion14.FIG.1shows the distal portion12of the tissue retraction system10positioned within an example body lumen16. Further,FIG.1shows that the proximal portion14of the tissue retraction system10may extend out of the body lumen16to a position outside the body. As shown inFIG.1, the tissue retraction system may include a tissue retraction device22. Additionally, the tissue retraction system10may include a delivery catheter26. The delivery catheter26may be constructed from a semi-rigid or compliant material such as a thermoplastic elastomer, silicone rubber, nylon, polyurethane, polyethylene terephthalate (PET), latex, or similar materials. The delivery catheter26may have a distal end region28and a proximal end region30. Further, a lumen32may extend through the delivery catheter26from proximal end region30to the distal end region28. As illustrated, the tissue retraction device22may be positioned along the distal end region28and within the lumen32of the delivery catheter26.

Additionally,FIG.1illustrates that the delivery catheter26(including the tissue retraction device22) may extend through an example medical device18. As discussed above, inFIG.1the medical device18may take the form of an endoscope, laproscope, needle, catheter, guide tube, or the like. The medical device18may include a distal portion23and a proximal portion25. Further,FIG.1illustrates that the distal portion23of the medical device18may be advanced within a portion of a body lumen16to a position adjacent a target tissue50, such as a lesion, while the proximal portion25of the medical device18may extend out of the body lumen16to a position outside the body.

Medical device18may include a lumen21extending from the proximal portion25to the distal portion23of the medical device18. In some examples, the lumen21may be referred to as the “working channel” of the medical device18. The lumen21may be designed to permit a variety of medical devices to pass therethrough. For example, a physician may pass or exchange a variety of medical devices through the working channel21over the course of a given medical procedure. For example, as illustrated inFIG.1, the delivery catheter26(including the tissue retraction device22) may extend through the lumen21of the medical device18. In other words,FIG.1illustrates that a physician may insert the distal end28of the delivery catheter26into the proximal portion25of the medical device18(which is outside the body), advance the delivery catheter26through the lumen21whereby the distal end28of the delivery catheter may eventually extend out of the distal portion23of the medical device18to a position adjacent the target tissue50.

The proximal end30of the delivery catheter26may include a control member42. The control member42may be utilized as a grip to control the translation of the delivery catheter26. Further, the control member42may also permit a user to rotate the delivery catheter26. As will be described in greater detail below, the control member42may be utilized by a physician to advance the distal end28of the delivery catheter26to a position adjacent a target tissue50prior to deploying the tissue retraction device22from the distal end28of the delivery catheter26.

In some examples, the medical device18may include additional features. For example, the medical device18shown inFIG.1may include an accessory feature20(e.g., light, camera, etc.) positioned on the distal portion23of the medical device18. Further, other medical devices18having additional features may be utilized in conjunction with the tissue retraction system10.

As illustrated inFIG.1, in some examples the tissue retraction system10may include a manipulating device34(“manipulator”) designed to advance (e.g., push, deploy, etc.) the tissue retraction device22out of the distal end28of the delivery catheter26. As will be described in greater detail below, once the manipulator34has pushed the tissue retraction device22out of the delivery catheter26, it may also be used to position and/or manipulate the tissue retraction device22within the body lumen16.

As shown inFIG.1, the manipulator34may extend within the lumen32of the delivery catheter26. In other words,FIG.1illustrates that a distal end38of the manipulator34may extend from the proximal end30of the delivery catheter26(which is outside the body), through the lumen32of the delivery catheter26whereby the distal end38of the manipulator34may be positioned adjacent the proximal end of the tissue retraction device22.

The proximal end40of the manipulator34may include a handle member44. Handle member44may include one or more finger grips45which permit a user to grasp and thereby advance (e.g., translate) the distal end38of the manipulator within the lumen32of the delivery catheter26. In other words, by grasping and manipulating the handle44, a user may be able to translate the manipulator34along the longitudinal axis of the delivery catheter26. The handle design illustrated inFIG.1is a schematic. Other handle designs are contemplated. For example, handle designs that include different grip arrangements, ergonomic features, etc. that may be utilized with the tissue retraction system10(and components thereof) described herein are contemplated.

The distal end38of the manipulator34may include a grasping member39(e.g., forceps, jaws, etc.). When positioned within the lumen32of the delivery catheter26, the grasping member39may be in a closed position (e.g., the jaws of the grasping member39may be closed and contacting one another). Further, the handle member44may be designed to control the opening and/or closing of the grasping member39. In other words, when the grasping member39is advanced to a position outside of the lumen32of the delivery catheter26, a user may manipulate the handle member44to open and/or close the grasping member39.

As described above, the manipulator34may be utilized to deploy the tissue retraction device22out of the distal end28of the delivery catheter26. Specifically, it can be appreciated that, when positioned adjacent to tissue target50, a user may advance the manipulator34in a proximal-to-distal direction within the lumen32of the delivery catheter26such that the grasping member39may contact and push the proximal end of the tissue retraction device22out of the distal end28of the delivery catheter26.

In at least some examples contemplated herein, the manipulator34and the tissue retraction device22may be positioned within the delivery catheter26as depicted inFIG.1prior to the delivery catheter26being advanced through the lumen21of the medical device18. In other words, in some examples, both the manipulator34and the tissue retraction device22may be “pre-loaded” into the delivery catheter26prior to being inserted and advanced through the working channel21of the medical device18to a position adjacent to target tissue50. In other examples, however, only the tissue retraction device22may be preloaded into the delivery catheter26and advanced within the lumen21of the medical device18to a position adjacent to target tissue50, after which the manipulator34may be separately inserted into the lumen21of the medical device18and advanced to a position in which grasping member39is adjacent and/or contacting the proximal end of the tissue retraction device22.

It can be appreciated from the above discussion that the tissue retraction system10may be designed such that the delivery catheter26and the manipulator34may be moved (e.g., translated, rotated, etc.) relative to one another. For example, once the distal end28of the delivery catheter26is positioned adjacent to the target tissue50(with the manipulator34positioned adjacent to the distal end of the tissue retraction device22), a user may grasp both the control member42and the handle member44. This may permit the user to maintain the distal end28of the delivery catheter26in a fixed position while advancing the manipulator34in a distal direction such that the grasping member39moves distally relative to the distal end28of the delivery catheter26. It can be appreciated that this relative movement may push the tissue retraction device22out of the distal end28of the delivery catheter26.

In other examples, it can be appreciated that instead of a user advancing the manipulator34in a distal direction to deploy the tissue retraction device22, the user may, alternatively, retract the delivery catheter26while maintaining the manipulator34in a fixed position. The retraction of the delivery catheter26may “uncover” the tissue retraction device22, thereby releasing it from the lumen32of the delivery catheter26.

FIG.2illustrates an example tissue retraction device22. The tissue retraction device22may include one or more engagement members51(e.g., clip, clasp, fastener, clamp, etc.). For example,FIG.2illustrates that the tissue retraction device22may include a first engagement member52aand a second engagement member52b. The first engagement member52amay include a first end54aand a second end56a. The first end54amay include one or more jaws61a(e.g., end effectors). The jaws61amay be designed such that they move relative to one another.FIG.2further illustrates that the second end56aof the first engagement member52amay include a spring60a. It can be appreciated that the spring60amay be designed to provide a compressive force that is translated through the body of the first engagement member52ato the jaw members61a, thereby biasing the jaw members61ain a closed position (e.g., a position in which the jaw members61aare contacting one another).

In some examples, the ends of the jaw members61amay not necessarily contact one another while in a closed position. The jaw members61amay be spaced apart from one another while in a closed position. Spacing the jaw members61aapart from one another while in a closed position may permit additional compressive force to be generated when in contact with tissue. This additional compressive force could be termed “preload.” The range of preload forces could vary from about 5 grams of force to about 200 grams of force, or about 15 grams of force to about 40 grams of force.

It can be appreciated that the engagement members51depicted in the examples disclosed herein are schematic. In other words, it is contemplated that the engagement members51described herein may include alternative design arrangements, features, geometries etc. without departing from the scope of the examples contemplated herein. For example, it is contemplated that the spring60aof the first engagement member52amay be positioned between the first end54aand the second end56aof the first engagement member52a). Additionally, it is contemplated that the jaws (e.g., end effectors) may have a variety of different shapes and/or geometries without departing from the scope of the examples contemplated herein. Other variations are contemplated.

FIG.2further illustrates that the first engagement member52amay include one or more gripping members58a. For example,FIG.2illustrates that the gripping member58amay be formed from the same material as the jaw member61a. In other words, the jaw61aand the gripping member58amay be formed as a monolithic component. For example, the jaws61a(e.g., end effectors) and the gripping members may be metal injection molded (MIM), conventionally machined, stamped, additive manufactured or the like. However, this is not intended to be limiting. Rather, it is contemplated that the jaw61aand the gripping member58amay be formed as two separate components which are attached (e.g., welded, glued, press fit, etc.) together to form the structure shown inFIG.2. Additionally,FIG.2illustrates that, in some examples, a portion of the gripping member58amay be designed to engage, mate, interconnect, attached to, etc. the spring60a. For example,FIG.2illustrates a portion of the spring60aextending into a channel of the gripping member58a. The spring60amay be rigidly attached (e.g., weld, affixed, etc.) to the gripping member58a.

As described above, after the tissue retraction device22has been deployed out of the distal end28of the delivery catheter26, the manipulator34may be utilized to position and/or attach the tissue retraction device22to the target tissue50within body lumen16. It can be appreciated that the gripping members58amay be designed to engage the grasping member39(located on the distal end38of the manipulator34). In other words, the gripping members58amay provide an interface for which the grasping member39may engage, attach, grip, grab, capture, etc. the first engagement member52a.

Furthermore, the gripping members58amay be designed such that they permit the manipulator34to efficiently acquire, position (and/or reposition), and open/close the jaws61aof the first engagement member52a. WhileFIG.2depicts the gripping members58apositioned between the first end54aand/or the second end56aof first engagement member52a, it is contemplated that the gripping members58amay be located along other portions of first engagement member52a. For example, the gripping members58amay be positioned on the first end54aand/or the second end56aof first engagement member52a.

As discussed above, the tissue retraction device22may include more than one tissue engagement member (e.g., another engagement member in addition to the first tissue engagement member52adescribed above). For example,FIG.2illustrates that the tissue retraction device22may include a second tissue engagement member52b. The second tissue engagement member52bmay be similar in form and function to the first tissue engagement member52a. For example, the second tissue engagement member52bmay include a first end54band a second end56b. The first end54bmay include one or more jaws61b. The jaws61bmay be designed such that they move relative to one another.FIG.2further illustrates that the second end56bof the second tissue engagement member52bmay include a spring60b. It can be appreciated that the spring60bmay be designed to provide a compressive force that is translated through the body of the second engagement member52bto the jaw members61b, thereby biasing the jaw members61bin a closed position (e.g., a position in which the jaw members61bare contacting one another). It can be appreciated that the second engagement member52bdepicted in the examples disclosed herein is schematic. In other words, it is contemplated that the second engagement member52bdescribed herein may include alternative design arrangements, features, geometries, etc. without departing from the scope of the examples contemplated herein. For example, it is contemplated that the spring60bof the second engagement member52bmay be positioned between the first end54band the second end56bof the second engagement member52b). Other variations are contemplated.

FIG.2further illustrates that the first engagement member52amay include one or more gripping members58b. For example,FIG.2illustrates that the gripping member58bmay be formed from the same material as the jaw member61b. In other words, the jaw61band the gripping member58bmay be formed as a monolithic component. For example, the jaws61a(e.g., end effectors) and the gripping members may be metal injection molded (MIM), conventionally machined, stamped, additive manufactured or the like. However, this is not intended to be limiting. Rather, it is contemplated that the jaw61aand the gripping member58amay be formed as two separate components which are attached (e.g., welded, glued, press fit, etc.) together to form the structure shown inFIG.2. Additionally,FIG.2illustrates that, in some examples, a portion of the gripping member58bmay be designed to engage, mate, interconnect, attached to, etc. the spring60b. For example,FIG.2illustrates a portion of the spring60bextending into a channel of the gripping member58b. The spring60bmay be rigidly attached (e.g., weld, affixed, etc.) to the gripping member58b.

FIG.2further illustrates that the tissue retraction device22may include one or a tether62(depicted as the dashed line inFIG.2) coupled to the first engagement member52a, the second engagement member52bor both the first engagement member52aand the second engagement member52b. The tether62may be a tubular member having a lumen extending therein. The tether62may be referred to as an elastic member, band, rope, cord, leash, strap, strand, etc. The tether62may include a variety of cross-sectional geometries. For example, the tether may be circular, rectangular, triangular, or the like. Further, the tether62may be bioabsorbable.

In at least some examples, the tether62may be elastomeric. In some examples, the tether62may be constructed from an elastomeric material such as latex, Nitrile® rubber, ethylene propylene diene rubber, silicone rubber, chloroprene, polychloroprene (e.g., Neoprene®), polyolefin, thermoplastic elastomer, polyisoprene, etc.

The tether member62may elongate from a first, unelongated (e.g., relaxed) position to a second, elongated position. It can be appreciated that when the tissue retraction device22is in an elongated position, the tissue elongation device is in tension, and therefore includes a retraction force which is pulling the first engagement member52atoward the second engagement member52balong the longitudinal axis of the tissue retraction device22.

As described above, prior to being deployed from the delivery catheter26, the tissue retraction device22may be positioned in an unelongated, relaxed state within the distal end28of the delivery catheter. Furthermore, proper alignment of the tissue retraction device22within the delivery catheter26(prior to deployment) must be maintained to ensure that the tissue retraction device22is efficiently deployed within the body lumen16. For example, it is important to prevent the tissue retraction device22from folding and/or wrapping upon itself (e.g., folding back on itself) while being advanced and/or manipulated within the distal end28of the delivery catheter26.

FIG.2illustrates that in some examples, the tissue retraction device22may include a support member64. In some instances, the support member64may be a tubular member having a lumen53extending therein. For example, the tissue retraction device22shown inFIG.2illustrates the tether member62extending within the lumen53of the support member64. Additionally,FIG.2illustrates that the support member64may extend between (e.g., be positioned between) the first tissue engagement member52aand the second tissue engagement member52b. WhileFIG.2depicts the support member64as a tubular member, other cross-sectional shapes of support member64are contemplated. For example, the cross-sectional shape of the support member64may be rectangular, triangular, ovular, square, or the like. Additionally, it is contemplated that the tissue retraction device22may include more than one support member64. For example, the tissue retraction device22may include 1, 2, 3, 4 or more support members.

As described above,FIG.2shows that the support member64may be disposed along the tether member62. For example, in some examples the tether member62may extend through the lumen53of the support member64. In at least some examples, the support member64may permit the tether62to compress into the lumen53of the support member64. Therefore, diameter of the lumen53of the support member64may be wide enough to permit the tether62to curl upon itself to be “stored” within the lumen of the support member64. Allowing the tether62to be stored within the lumen of the support member64may prevent the tether62from being entangled with the first engagement member52a.

Additionally, in at least some examples described herein, the support member64may include sufficient stiffness and column strength to withstand compression during packaging and storage prior to device delivery. Possible materials include polypropylene, PET, thermoplastic elastomers (TPE), polyethylene (PE), or high density polyethylene (HDPE) such as Celanese GUR HOSTALLOY731.

FIG.2further illustrates that the tether62may be coupled to the tissue engagement member52avia a coupler body36aand a connection member46a. As will be described in greater detail below, the connection member46amay include a post member48aand an attachment member47a.FIG.2further illustrates that a proximal end of the coupler body36amay extend within the lumen53of the tether member62. A compression member49amay be positioned overtop both the proximal end of the coupler body36aand the tether62, whereby the compression member49amay radially compress the tether62onto the proximal end of the coupler body36awith sufficient force to fixedly attach the tether62to the coupler body36a. In other words, the tether62may be attached to the coupler body36aby “sandwiching” the tether62between the coupler body36aand the compression49a. The compression member49amay include a variety of different structures without departing from the scope of the examples contemplated herein. For example, the compression member49amay include a compression ring, a suture, a clamp, a string, a knot, a crimped ultrasonic weld, a loop, etc.

As will be described in greater detail below, the post member48amay extend through an aperture57aformed in the coupler body36a, whereby a proximal end of the post member48amay be prevented from being pulled through the aperture57a. In other words, as will be illustrated inFIG.3below, the post member48amay include a proximal end which is designed to allow the post member48ato rotate while preventing the post member48afrom separating from the coupler body36a.

Additionally,FIG.2illustrates that the distal end of post member48amay be attached to the attachment member47a. For example,FIG.2illustrates that the attachment member47amay include a curved portion (e.g., a substantially C-shaped portion), which may resemble a partial ring.FIG.2further illustrates that the attachment member47amay extend through the looped portion of the spring60a, thereby coupling the attachment member47ato the tissue engagement member52avia the spring60a. Additionally,FIG.2illustrates that the attachment member47amay be attached to the distal end of the post member48a, thereby coupling the attachment member47ato the coupler body36avia the post member48a. It can be appreciated, therefore, that the connection member46a(which includes the attachment member47aand the post member48a) together with the coupler body36aand the compression ring49a, may couple the tissue engagement member52ato the tether member62.

It is noted that be above description my also apply to coupling the second tissue engagement member52bwith the tether62. For example, the second tissue engagement member52bmay be coupled to a coupler body36bvia a connection member46b. Similar to that described above, the connection member46bmay include an attachment member47band a post member48b. The attachment member47bmay be coupled to the spring60b. Additionally, the attachment member47bmay be attached to the post member48b. The post member48bmay extend through an aperture57b(not visible inFIG.2) in the coupler body36b, as described above. Further, the tether62may be attached to the coupler body36bvia radial compression of the compression ring49bonto the coupler body36b.

FIG.3is an exploded view of one end of the tissue retraction device22described above.FIG.3illustrates the individual components utilized to couple the tether member62to the tissue engagement member52a, as described above. For example,FIG.3illustrates the tissue engagement member52a, which includes spring60a. As shown inFIG.3, the spring60amay include a coiled portion through which the attachment member47amay extend. As described above and further illustrated inFIG.3, the attachment member47amay include a curved portion75awhich resembles a partial ring. Additionally, the attachment member47amay include an opening67awhich, for purposes of assembly, may permit the attachment to be inserted into the coiled portion of the spring60a.

FIG.3further illustrates both the compression member49aand the coupler body36a. In some examples the coupler body36amay include a channel55awhich extends circumferentially around the coupler body36a. The channel55amay be designed to mate with the compression member49a. For example, the width, depth and/or profile of the channel55amay mate with the width, thickness and/or profile of the compression member49a. As described above, the tether62may be radially compressed between the coupler body36aand the compression member49ato fixedly attach the tether62to the coupler body36a.

Additionally,FIG.3illustrates that the coupler body36amay include an aperture57athrough which the post member48amay extend. The diameter of the aperture57ais depicted as “X1” inFIG.3. Additionally,FIG.3illustrates that the post member48amay include a first end region59aand a second end region63a. The second end region63aof the post member48amay include a tapered portion. The tapered portion may include a diameter “Y1” which is greater than the diameter X1of the aperture57a. It can be appreciated that the post member48amay include a length which permits the post member48ato extend through the aperture57awhereby the first end region59amay be fixedly attached to the attachment member47a. For example, the first end region59aof the post member48amay be welded to the attachment member47a. It can further be appreciated that after the post member48ais extended through the coupler body36aand attached to the attachment member47a, the coupler body36amay be coupled to the attached combination of the attachment member47aand the post member48a.

FIG.3further illustrates that the lumen53of the tether62may be sized such that it may be positioned over a portion of the coupler body36a. For example, the tether62may be positioned overtop the proximal portion of the coupler body36asuch that a portion of the tether62may be positioned along the channel55a. As described above, the compression member49amay be positioned overtop the tether62such that it radially compresses the tether62onto the coupler body36a, thereby attaching the tether62to the coupler body36a.

FIG.4illustrates an example tissue engagement member52a. As discussed above, the tissue engagement member52amay include a jaw members61a, gripping members58aand a coiled spring60a.FIG.4further illustrates that the spring portion60amay include one or more stems68athat engage (e.g., mate) with a groove portion69alocated in the gripping member58a. It is contemplated that the stems68amay be attached within the groove69awith a variety of techniques. For example, the stem68amay be welded, press fit, glued, etc. within the groove portion69a.

Additionally,FIG.4illustrates that the jaws61amay each include one or more teeth65. It can be appreciated that the teeth65may include a variety of different of shapes which are oriented in a variety of different configurations. Each jaw61aillustrated inFIG.4may include two teeth65, wherein the teeth65of one jaw61amay mirror the teeth65of the other jaw61a. In other words, the teeth65of the “top” jaw may be aligned with the teeth65of the “bottom” jaw. Further,FIG.4illustrates that the particular arrangement of the teeth results in an aperture66located in a central region of the teeth65. Furthermore, it can be appreciated that the jaws61amay be designed to exhibit a slope facing the coiled portion60aof the first engagement member52a. For example,FIG.4illustrates that the “face” of each jaw61adefining each of the teeth65may be sloped inward at an angle, depicted as “0” inFIG.4.FIG.4illustrates that the angle may create a sharp point that may engage tissue more aggressively. The direction of the slope enhances tissue engagement by discouraging captured tissue from disengaging.

FIG.5illustrates another example tissue retraction device122. The tissue retraction device122may be similar in form and function to the tissue retraction device22described above. For example, the tissue retraction device may include a first tissue engagement member52a(including jaws61a, gripping members58aand spring60a) and a second tissue engagement member52b((including jaws61b, gripping members58band spring60b). Additionally, the first tissue engagement member52amay be coupled to a tether62via a connection member146aand a coupler body136a. Similarly, the second tissue engagement member52bmay be coupled to the tether62via a connection member146band a coupler body136b. As discussed above, the tissue retraction device122may include a support member64disposed along the tether62.

FIG.6is an exploded view of one end of the tissue retraction device122described above. Similar to that described above with respect toFIG.3,FIG.6illustrates the individual components utilized to couple the tether62to the tissue engagement member52ashown inFIG.5. For example,FIG.6illustrates the tissue engagement member52a, which includes the gripping members58aand the spring60a. Additionally,FIG.6illustrates the tether62including the lumen53extending therein. However,FIG.6further illustrates the individual components of the connection member146a(described inFIG.5) and which, in conjunction with the coupler body136a, couple the tissue engagement member52awith the tether62.

To that end, the connection member146a(described inFIG.5) may include a post member148a, a first fitting167aand a second fitting168a. The post member may include a first end159aand a second end163a. It can be appreciated that the first fitting167aand the second fitting168amay be designed to mate with one another. In other words, the first fitting167aand the second fitting168amay be two separate components which “snap” together to form a single component. Additionally, it can be further appreciated that the first fitting167aand the second fitting168amay include one or more “voids” or “protrusions” which are designed to capture both the coiled portion of the spring60aand a projection170alocated on the first end159aof the post member148a.

For example, the projection170amay be designed to engage a void171a, half of which is formed in the first fitting167aand half of which is formed in the second fitting168a(it is noted that the half of the void171aformed in the first fitting167acannot be seen inFIG.6). Additionally,FIG.6illustrates a first protrusion172aextending outward from the second fitting168awhich is designed to mate with a second protrusion173aextending outward from the first fitting167a. As discussed above, the first protrusion172aand the second protrusion173amay be designed to interlock within one another through an opening174aformed in the spring portion60a, thereby capturing the spring portion60abetween the first fitting167aand a second fitting168a.

Additionally,FIG.6illustrates that the coupler body136amay include an aperture157athrough which the post member148amay extend. The diameter of the aperture157ais depicted as “X2” inFIG.6. Additionally,FIG.6illustrates that the post member148amay include a first end region159aand a second end region163a. The second end region163aof the post member148amay include an enlarged portion. The enlarged portion may include a diameter “Y2” which is greater than the diameter X2 of the aperture157a. It can be appreciated that the post member148amay include a length which permits the post member148ato extend through the aperture157a, whereby the projection170aof the first end region159amay be fixedly attached with the void171aformed via the first fitting167aand the second fitting168a. It can further be appreciated that after the post member148ais extended through the coupler body136aand attached to the first fitting167aand the second fitting168a, the coupler body136amay be coupled to the attached combination of the first fitting167a, the second fitting168aand the post member148a.

FIG.6further illustrates that the lumen53of the tether62may be sized such that it may be positioned over a portion of the coupler body136a. For example, the tether62may be positioned overtop the proximal portion of the coupler body136asuch that a portion of the tether62may be positioned along a channel155a(extending circumferentially around the coupler body136a). As described above, a compression member (e.g., compression ring, suture, band, clamp, etc.) may be positioned overtop the tether62such that it radially compresses the tether62onto the coupler body136a, thereby attaching the tether62to the coupler body136a.

FIGS.7-9illustrate different example tissue engagement members. The tissue engagement members illustrated inFIGS.7-9may differ in size, shape, geometry, etc. without departing from the scope of the examples contemplated herein. For example, the particular shape and geometries of the end effectors (e.g., jaws, teeth, gripping members, etc.) disclosed herein may be different. However, it is contemplated that any of the features disclosed with respect to an example tissue engagement member may be compatible with any other tissue engagement member disclosed herein.

FIG.7illustrates another example tissue engagement member251. The tissue engagement member251may be similar in form and function to the tissue engagement member51described above. For example, the tissue engagement member251may include jaws261, gripping members258and a spring260. Additionally,FIG.7illustrates that each of the jaws261may include a single, flat tooth265, wherein each tooth265faces the other. As described above with respect to the tissue engagement member52ashown inFIG.4, each tooth265may be sloped such that it is angled toward the coiled portion260. The direction of the slope enhances tissue engagement by discouraging captured tissue from disengaging.

FIG.8illustrates another example tissue engagement member351. The tissue engagement member351may be similar in form and function to other tissue engagement members described above. For example, the tissue engagement member351may include jaws361, gripping members358and a spring360. Additionally,FIG.8illustrates that the “top” jaw361ofFIG.8may include a first tooth365and a second tooth375, wherein the first tooth365is wider than the second tooth375. Additionally, the first tooth365may be spaced away from the second tooth375to create a gap366between the first tooth365and the second tooth375. Similarly, the “bottom” jaw361ofFIG.8may include a first tooth365and a second tooth375, wherein the first tooth365is wider than the second tooth375. Additionally, the first tooth365may be spaced away from the second tooth375to create a gap366between the first tooth365and the second tooth375. Additionally, it can be appreciated that the teeth may be arranged such that the first tooth365of the top row is aligned with the gap366of the bottom row, while the first tooth365of the bottom row is aligned with the gap366of the top row. In other words, teeth of the top row are designed to interdigitate with the teeth of the bottom row.

Furthermore, it can be appreciated that each of the first teeth365and each of the second teeth375may be sloped such that they are angled toward the coiled portion360(as described above with respect to other tissue engagement members). The direction of the slope enhances tissue engagement by discouraging captured tissue from disengaging.

FIG.9illustrates another example tissue engagement member451. The tissue engagement member451may be similar in form and function to other tissue engagement members described above. For example, the tissue engagement member451may include jaws461, gripping members458and a spring460. Additionally,FIG.9illustrates that the jaw461may each include one or more teeth465. It can be appreciated that the teeth465may include a variety of different of shapes which are oriented in a variety of different configurations. Each jaw461illustrated inFIG.9may include two teeth465, wherein the teeth465of one jaw461may mirror the teeth465of the other jaw461. In other words, the teeth465of the “top” jaw may be aligned with the teeth465of the “bottom” jaw. Further,FIG.9illustrates that the particular arrangement of the teeth465results in an aperture466located in a central region of the teeth465.

Furthermore, as described above with respect to other tissue engagement members, each tooth465may be sloped such that it is angled toward the coiled portion460. The direction of the slope enhances tissue engagement by discouraging captured tissue from disengaging.

FIGS.10-14illustrate a series of steps to deploy and utilize the tissue retraction system10described above. The tissue retraction device22may be utilized to lift and reposition target tissue which has been dissected by a clinician. As will be made clear by the following illustrations, as the clinician cuts away target tissue, the tissue retraction device may lift and reposition it, thereby providing the clinician with an unobstructed view of the ongoing procedure.

FIG.10illustrates a first step in utilizing the tissue retraction system10in a dissection procedure. As described above and illustrated inFIG.10, the clinician may first advance the manipulator34in a proximal-to-distal direction (relative to the distal end28of the delivery catheter26). This forward movement of the manipulator will force the grasping member39of the manipulator to push the tissue retraction device22forward and out the distal end28of the delivery catheter26.FIG.10illustrates the tissue retraction device22having been advanced out of the distal end28of the delivery catheter26, whereby it is positioned adjacent to the tissue target50(e.g., a cancerous lesion).

FIG.11illustrates an example second step in utilizing the tissue retraction system10in a dissection procedure.FIG.11illustrates that a clinician may manipulate the distal end38of the manipulator34to grasp the first engagement member52a(for clarity, the grasping member39is shown in a closed configuration inFIG.11. It can be appreciated that the grasping member39may open up to grasp the first engagement member52a). For example, the clinician may manipulate the handle44of the tissue retraction system10to open the jaws of the grasping member39. Once opened, the jaws of the grasping member may engage the gripping members58aof the first engagement member52a. After engaging the gripping members58a, the clinician may close the jaws of the grasping member39, thereby opening the jaws61aof the first engagement member52a. Using the grasping member39, the clinician may then position the jaws61aonto the surface of the target tissue50. By releasing the grasper39from the gripping members58b, the jaws61aof the first engagement member52amay close and attach the jaws61a(and, by extension, the first engagement member52a) to the surface of target tissue50.

FIG.12illustrates an example third step in utilizing the tissue retraction system10in a dissection procedure.FIG.12illustrates that a clinician may manipulate the distal end38of the manipulator34to grasp the second engagement member52b(for clarity, the grasper39is shown in a closed configuration inFIG.12). It can be appreciated that the grasper39may open up to grasp the second engagement member52b. For example, the clinician may manipulate the handle44(described above) of the tissue retraction system10to open the jaws of the grasper39. Once opened, the jaws of the grasper may engage the gripping members58bof the second engagement member52b. After engaging the gripping members58b, the clinician may close the jaws of the grasper39, thereby opening the jaws61bof the second engagement member52b. The clinician may then pull on the second engagement member52b, thereby lengthening the tissue retraction device22(as described above with respect toFIG.2AandFIG.3). Once the tissue retraction device is elongated to a desired length (which may be confirmed visually via reference markers66as described above), the clinician may position the jaws61bof the second engagement member52bonto the surface of the target tissue site50. By releasing the grasping member39from the gripping members58b, the jaws61bof the second engagement member52bmay close, thereby attaching the jaws61b(and, by extension, the second engagement member52b) to the inner surface of body lumen16.

FIG.13illustrates an example fourth step in utilizing the tissue retraction system10in a dissection procedure.FIG.13illustrates that after the tissue retraction device22has been attached to both the target tissue site50and to the inner surface of the body lumen16at a position spaced away from the target tissue site (which places the tissue retraction device22in tension), the clinician may exchange the manipulator34for a cutting tool74. The cutting tool74may include a cutting member76positioned at the target tissue50. Further, the cutting tool74may be advanced within the working channel21of the medical device18as described above.

FIG.14illustrates an example fifth step in utilizing the tissue retraction system10in a dissection procedure.FIG.14illustrates the clinician performing the tissue dissection by utilizing the cutting tool74to cut a portion of the target tissue50. As can be appreciated fromFIG.14, as the cutting tool74cuts a portion of the target tissue50, the tissue retraction device22retracts (via the retraction of tether members62a/62b), and thereby lifts the dissected portion78of the target tissue50up and away from the plane of tissue being cut by the physician. By lifting and retracting the dissected portion78of the target tissue50, a clear, unobstructed view of the procedure is maintained for the clinician. It is noted that, if necessary, the engagement members52a/52bof the tissue retraction system10may be repositioned. In other words, adjustments in tension and/or direction may be imparted into the tissue retraction system10as desired.

It should be noted that the features of any of the tissue retraction systems described with respect to particular figures and/or embodiments are not limited to that particular example. Rather, it is contemplated that all of the features or examples disclosed with respect to a single example may be incorporated into any other example disclosed herein.

The materials that can be used for the various components of tissue retraction system10and the various devices disclosed herein may include those commonly associated with medical devices. For simplicity purposes, to the extent the following discussion makes reference to tissue retraction system10, it is not intended to limit the devices and methods described herein only to tissue retraction system10, as the discussion may be applied to other similar devices disclosed herein.

Tissue retraction system10and/or other components of tissue retraction system10may 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, Polyurethane85A), 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), Marlex high-density polyethylene, 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-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), styrene ethylene buthylene styrene (SEBS), Thermoplastic Elastomers (TPE) (such as Medalist® available from Teknor Apex and/or Mediprene® available from Hexpol TPE), 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).

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.

In at least some embodiments, portions or all of tissue retraction system10and/or other components of tissue retraction system10may 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 tissue retraction system10and/or other components of tissue retraction system10in 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 tissue retraction system10and/or other components of tissue retraction system10to achieve the same result.

In some embodiments, a degree of Magnetic Resonance Imaging (MRI) compatibility is imparted into tissue retraction system10and/or other components of tissue retraction system10. For example, tissue retraction system10and/or other components of tissue retraction system10, 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. Tissue retraction system10and/or other components of tissue retraction system10, 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.

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 disclosure's scope is, of course, defined in the language in which the appended claims are expressed.