Patent Description:
Tissue samples are often examined to determine the presence of a pathological disorder. Endoscopic biopsy forceps may be used in conjunction with an endoscope for taking certain tissue samples from the human body for analysis. Often, the samples must be obtained from deep within the body at locations that are difficult to access by simply using forceps jaws (e.g., tissue from an area accessible via a tortuous path). In certain cases, the quality of tissue that is easily accessible may not be satisfactory for pathologists to make an accurate diagnosis. Furthermore, known forceps jaws are often difficult to maneuver for tangential bites. <CIT> is considered the closest prior art and discloses a disposable biopsy forceps comprising jaws at the distal end and a distally extending spike therebetween, configured to secure a tissue sample, the jaws and the spike being molded integrally in a single piece. The device further comprises a jaw support attached to the jaws and a jaw actuator slidably received in a slot of the jaw support.

The invention is defined by the independent claim. The dependent claims are related to particular embodiments of the invention. The present invention relates to a biopsy forceps device. The biopsy forceps device includes a control member extending from a proximal end to a distal end; a yoke coupled to a distal end of the control member, the yoke including a tissue contacting structure extending distally from a distal end of the yoke; and first and second jaws coupled to the yoke. The first and second jaws are biased toward an open configuration, in which the jaws are separated from one another to receive target tissue therebetween and being moveable to a closed configuration, in which cutting edges of the jaws are moved toward one another to cut a portion of the target tissue from surrounding tissue, the first and second jaws defining a tissue receiving space therebetween to house the cut tissue. The device also includes a capsule slidably receiving the yoke and a proximal portion of each of the first and second jaws. The first and second jaws are constrained to the closed configuration when withdrawn proximally to a first position within the capsule, and the first and second jaws being configured so that, when the first and second jaws are moved to a second position distal of the first position, distal portions of the jaws are freed from the constraint of the capsule and spread apart from one another under their natural bias to the open configuration, the tissue contacting structure being positioned so that, when the yoke and the first and second jaws are moved distally and the first and second jaws move to the open configuration, the tissue contacting structure extends distally to engage a portion of tissue between the first and second jaws to anchor the engaged portion of tissue again lateral movement as the first and second jaws contact the tissue adjacent to the engaged portion of tissue.

In one embodiment, the first and second jaws include concave inner surfaces defining a substantially hemispherical cup.

In one embodiment, the yoke includes radially extending protrusions that contact an inner surface of the capsule to center the yoke and the first and second jaws within the capsule.

In one embodiment, the first jaw is coupled to a first side of the yoke diametrically opposed, relative to a longitudinal axis of the capsule, to a second side of the yoke to which the second jaw is coupled.

According to the invention, the control member is non-rotatably coupled to the yoke and the yoke and the first and second jaws are rotatably received within the capsule so that, rotation of the control member rotates the yoke and the first and second jaws within the capsule.

In one embodiment, the device further includes a handle which, during use of the device, remains outside the body accessible to a user of the device, the handle including a first actuator operable to move the control wire proximally and distally relative to the capsule and a second actuator to rotate the control wire about the longitudinal axis of the capsule.

In one embodiment, the end effector has a length of less than <NUM>.

In one embodiment, the end effector has a length no more than <NUM>.

In one embodiment, the device further includes a flexible elongated member extending from a proximal end coupled to the handle to a distal end coupled to the capsule, the elongated member receiving the control member therein.

In one embodiment, the elongated member is sized to be slidably received within a working channel of an endoscope.

In one embodiment, the elongated member is coupled to the capsule via a bushing.

In one embodiment, the capsule rotates about the longitudinal axis of the capsule.

In one embodiment, the elongated member is formed as a flexible coil. According to the invention, the tissue contacting structure is formed as a tissue penetrating spike.

In one embodiment, the device further includes a plurality of protrusions at a distal end of the capsule extending radially inward toward a longitudinal axis of the capsule to prevent the first and second jaws from sliding distally out of the capsule.

The present disclosure also relates to a non-claimed method for obtaining a tissue sample which includes inserting a distal portion of a biopsy forceps assembly to a target area within a living body, the distal portion including: a control member extending from a proximal end to a distal end; and an end effector including first and second jaws movable between an open configuration in which the first and second jaws are separated from one another to receive target tissue therebetween, and a closed configuration, in which cutting edges of the first and second jaws are moved toward one another to cut the target tissue away from surrounding tissue, the first and second jaws defining a tissue receiving space therebetween to house the cut tissue; moving the control member distally relative to the first and second jaws to move a yoke coupled between the control member and the first and second jaws distally so that a distal projection of the yoke member contacts the target tissue, the yoke being coupled to the first and second jaws so that distal movement of the yoke moves the first and second jaws to the open configuration; and moving the control member proximally relative to the first and second jaws to move the jaws to the closed configuration so that the cutting edges of the first and second jaws sever the target portion of tissue from the surrounding tissue.

In one example, the method further includes inserting the biopsy forceps assembly through the working channel of an endoscope.

In one example, the yoke and the first and second jaws are slidably received within a capsule and wherein the yoke includes a plurality of radial projections sized to slidably engage an inner surface of the capsule to maintain the yoke and the first and second jaws centered within the capsule.

In one example, the device further includes a handle which, during use of the device, remains outside the body accessible to a user of the device, the handle including a first actuator operable to move the control member proximally and distally relative to the capsule and a second actuator to rotate the control member about the longitudinal axis of the capsule.

In one example, the method further includes rotating the second actuator in a first direction to rotate the distal portion of the biopsy forceps assembly about the longitudinal axis of the capsule relative to the handle.

The present disclosure may be further understood with reference to the following description and the appended drawings, wherein like elements are referred to with the same reference numerals. The present disclosure relates to an endoscopic forceps assembly for severing and retaining tissue samples. Exemplary embodiments of the present disclosure describe a forceps assembly that can be advanced through a working channel of a flexible endoscope, including, for example, a SpyScope™, or any other endoscopic device specifically designed and/or sized for use with the forceps assembly, and into a tissue tract. Current embodiments also include a more compact forceps design for increasing the passability and maneuverability of the forceps assembly through tight curvatures within the working channels of the endoscopic devices as well as along tortuous paths through, for example, the lumens of organs within a living body. It should be noted that the terms "proximal" and "distal," as used herein, are intended to refer to toward (proximal) and away from (distal) a user of the device.

As shown in <FIG> and <FIG>, a forceps assembly <NUM> according to an exemplary embodiment of the present disclosure includes a distal end effector <NUM>, a proximal actuator assembly <NUM>, and an elongate member <NUM> connecting the end effector <NUM> to the proximal actuator assembly <NUM>. The end effector <NUM>, as shown in <FIG>, includes first and second jaws <NUM>, <NUM>, respectively, and a yoke <NUM> that are slidably received within a capsule <NUM>. The yoke <NUM> is coupled to the first and second jaws <NUM>, <NUM> and also receives and is coupled to a core wire <NUM>. A proximal end of the capsule <NUM> is coupled to the elongated member <NUM> via a bushing <NUM>.

The proximal actuator assembly <NUM>, as shown in <FIG>, includes a handle <NUM> including a proximal thumb ring <NUM>, and a spool <NUM> that slides relative to the handle <NUM> over a longitudinal slotted member <NUM>. The elongate member <NUM>, in the present embodiment, is formed as a flexible coiled member and houses therein the control wire <NUM> that extends from the proximal actuator assembly <NUM> to the end effector <NUM>. The control wire <NUM> is coupled to the spool <NUM> and the elongated member <NUM> is coupled to a distal end of the longitudinal slotted member <NUM> so that, as the spool <NUM> is moved proximally and distally over the longitudinal slotted member <NUM>, the control wire <NUM> moves proximally and distally within the elongated member <NUM>.

As indicated above, the yoke <NUM> is coupled to the control wire <NUM> and to the jaws <NUM>, <NUM> while the capsule is coupled to the elongated member <NUM> via the bushing <NUM>. Thus, as the control wire <NUM> is moved proximally and distally through the elongated member <NUM> via movement of the spool <NUM> over the longitudinal slotted member <NUM>, the yoke <NUM> and the jaws <NUM>, <NUM> are moved proximally and distally through the capsule <NUM>. The jaws <NUM>, <NUM> are formed so that they are biased toward an open, tissue receiving configuration. Thus, as the jaws <NUM>, <NUM> are moved distally to extend out of the capsule <NUM>, the jaws <NUM>, <NUM> spread apart from one another so that target tissue may be received therebetween.

As the jaws <NUM>, <NUM> are drawn proximally back into the capsule <NUM>, radially outer surfaces of the jaws <NUM>, <NUM> contact the wall of the capsule <NUM> and are forced back toward a tissue gripping configuration. As will be described below, in the tissue gripping configuration, the jaws <NUM>, <NUM> are drawn together to grip, sever and retain tissue received therebetween. In order to facilitate a wide range of applications and reach targeted anatomical regions of small cross-section, the elongated biopsy forceps assembly <NUM> may be formed to a length of between <NUM> and <NUM>, and more preferably between <NUM> and <NUM>.

As can be seen in <FIG>, the yoke <NUM> includes two radially projecting portions <NUM> that extend radially outward from the yoke <NUM> to engage the inner surface of the capsule <NUM>. The projecting portions <NUM> keep the yoke <NUM> and the jaws <NUM>, <NUM> centered within the capsule <NUM> as the yoke <NUM> and the jaws <NUM>, <NUM> are moved proximally and distally within the capsule <NUM>. The capsule <NUM> has two protrusions <NUM> at the distal end that prevent the jaws <NUM>, <NUM> from sliding distally out of the capsule <NUM>. The protrusions <NUM> are sized and shaped to meet the projecting portions <NUM> as the jaws <NUM>, <NUM> and the yoke <NUM> move distally out of the distal end of the capsule <NUM>.

The yoke <NUM> also includes a tissue penetrating spike <NUM> projecting distally therefrom. The spike <NUM> of this embodiment extends substantially along a longitudinal axis L of the capsule <NUM> so that the spike <NUM> remains substantially centered between the jaws <NUM>, <NUM> as the jaws <NUM>, <NUM> are moved between the open and tissue gripping configurations. Because the jaws <NUM>, <NUM> are opened through their own natural bias and no linkage (e.g., a four bar linkage) is required to connect the jaws <NUM>, <NUM> to the control wire <NUM>, the spike <NUM> may pass directly along the longitudinal axis L without interfering with the action of the jaws <NUM>, <NUM>.

<FIG> depicts the end effector <NUM> with the first and second jaws <NUM>, <NUM> in the open, tissue-receiving configuration. The first and second jaws <NUM>, <NUM> of this embodiment are generally cup-shaped with convex outer surfaces and concave inner surfaces such that, in the closed configuration, an inner tissue-receiving space <NUM> is formed between the first and second jaws <NUM>, <NUM>. The outer perimeter edges of the first and second jaws <NUM>, <NUM> are formed as tissue cutting edges <NUM>, <NUM> configured to mate with one another when in the closed configuration. For example, in this embodiment, the perimeters of the first and second jaws <NUM>, <NUM> include complimentary serrated edges or teeth such that peaks of the serrations of the first jaw <NUM> fit within the valleys of the serrations of the second jaw <NUM>, and vice versa. In another embodiment, the distal cutting edges <NUM>, <NUM> may be straight cutting edges.

The control wire <NUM>, as shown in <FIG>, extends from a proximal end <NUM> coupled to the spool <NUM> via a sleeve <NUM> coupled thereto to a distal end <NUM> coupled to the yoke <NUM>. In this embodiment, the sleeve <NUM> is a hypotube crimped over the control wire <NUM>. The sleeve <NUM> is coupled to a rotation knob <NUM> received within the longitudinal slotted member <NUM> distally of the spool <NUM> so that, as the rotation knob <NUM> is rotated about the longitudinal slotted member <NUM>, the control wire <NUM> rotates relative to the handle <NUM>. The sleeve <NUM> is rotatably coupled to the spool <NUM> so that, as the control wire <NUM> is rotated via the rotation knob <NUM>, the spool remains in position without rotating. In addition, as seen in <FIG>, the proximal end of the elongated member <NUM> is coupled to the distal end of the handle <NUM> via a retainer <NUM>.

The spike <NUM> aids in maintaining a target portion of tissue in a desired position relative to the jaws <NUM>, <NUM> as the target portion of tissue is captured within the end effector <NUM>. Specifically, as shown in <FIG>, when the jaws <NUM>, <NUM> are extended distally from the capsule and move to the open, tissue receiving configuration, the spike <NUM> is exposed centered between the now separated jaws <NUM>, <NUM>. As the end effector <NUM> is advanced distally toward the target tissue, the spike <NUM> penetrates the target tissue so that, as the jaws <NUM>, <NUM> are drawn toward one another, engagement between the tissue on either or both sides of the spike <NUM> by the first jaw <NUM> and/or the second jaw <NUM> does not draw the target tissue off center possibly including non-targeted tissue in the sample obtained or in moving some of the targeted tissue out of center so that some of this target tissue is not included in the portion that will be gripped and severed by the jaws <NUM>, <NUM>.

By maintaining the tissue toward which the user has directly aimed the end effector centered between the jaws <NUM>, <NUM>, the spike <NUM> ensures that the amount of targeted tissue included in the sample is maximized. Those skilled in the art will understand that other types of tissue centering structures may be used. For example, the spike <NUM> may be replaced by a projecting structure that is designed to engage the target tissue and otherwise maintain the target tissue centered between the jaws <NUM>, <NUM>, terminating in a small flat square shape, an adhesive structure, a roughened surface, etc. so long as the structure resists lateral forces exerted, for example, by the jaws <NUM>, <NUM> against the adjacent tissue.

In an exemplary embodiment, the end effector <NUM> has a reduced length rigid portion that enables the forceps assembly <NUM> of this embodiment to more easily traverse tortuous paths around tight turning radii. For example, by eliminating the linkages associated with certain end effectors the end effector <NUM> of this embodiment may have a rigid portion of, for example, <NUM>. The shortening of these components and, thus, the end effector <NUM>, allows the end effector <NUM> to more easily pass through acute curvatures within a living body. Furthermore, the reduced rigid length of the end effector <NUM>, in combination with the spike <NUM>, reduces the number of bites required to grab a desired amount of target tissue. This reduction in the number of bites required to grab the desired amount of target tissue reduces the number of insertions of the end effector <NUM> into the tissue, reducing trauma to the surrounding tissue.

Turning back to <FIG>, the elongate member <NUM> is coupled to, and extends proximally from, the bushing <NUM>. The elongate member <NUM> and the bushing <NUM> may be coupled to one another via any of a variety of methods including, but not limited to, welding, soldering, adhesives, etc. In an exemplary embodiment, the elongate member <NUM> may be formed of a flexible, closely wound, stainless steel helical coil and may further include a thin covering or coating, such as a layer of polytetrafluroethelene (PTFE) as would be understood by those skilled in the art. The flexible coil <NUM> may have, for example, a circular, rectangular, or other cross-section. As one skilled in the art would understand, other shapes for the cross-section may be selected depending on the particular application. The PTFE reduces friction between the working channel of the endoscope and the elongate member <NUM> so that the forceps assembly <NUM> slides more easily within the endoscope.

In use, the forceps assembly <NUM> is maintained in the closed configuration and inserted into the body, e.g., through the working channel of an insertion instrument such as the endoscope which may be, for example, a SpyScope DS. For example, an endoscope may be inserted into the duodenum to retrieve a tissue sample from the biliary tract. This often requires the deployment of the end effector <NUM> at an acute angle relative to a longitudinal axis of the duodenum due to the complex anatomy and location of the biliary tract. The reduced rigid length of the end effector <NUM> facilitates passage of the forceps assembly <NUM> through these tight curves, enhancing maneuverability and positioning at a desired location. The elongated member <NUM> along with the end effector <NUM> is passed through the endoscope along the tortuous path to enter a common bile duct. Once the distal end effector <NUM> has been positioned as desired adjacent to the target tissue, the spool <NUM> is advanced distally over the handle <NUM>, moving the control wire <NUM> and the yoke <NUM> distally. This distal movement of the yoke <NUM> moves the jaws <NUM>, <NUM> distally to extend out of the capsule <NUM>.

As the jaws <NUM>, <NUM> move distally out of the capsule <NUM>, the natural bias of these jaws <NUM>, <NUM> moves them apart from one another into the open, tissue receiving configuration. As the jaws <NUM>, <NUM> open and the control wire <NUM> advances forward, the spike <NUM> pierces the target tissue, preventing this tissue from being moved laterally off center which helps to increase the depth to which an obtained sample of the target tissue may extend as seen in <FIG>. The first and second jaws <NUM>, <NUM> are then closed by withdrawing the control wire <NUM> proximally, drawing the yoke <NUM> and the first and second jaws <NUM>, <NUM> proximally until contact between the jaws <NUM>, <NUM> and the capsule draws the jaws toward one another to grip and sever the target tissue.

As the first and second jaws <NUM>, <NUM> close, the cutting edges along the profile of the first and second jaws <NUM>, <NUM> sever the tissue captured in the tissue receiving space <NUM> of the first and second jaws <NUM>, <NUM> from the surrounding tissue and this severed tissue sample is retained between the closed jaws <NUM>, <NUM>. Once the tissue has been collected within the tissue receiving space <NUM> between the first and second jaws <NUM>, <NUM>, the forceps assembly <NUM> is retracted proximally from the endoscope and the tissue is retrieved from the first and second jaws <NUM>, <NUM> for diagnosis. If more tissue is preferred for the diagnosis, the forceps assembly <NUM> may be re-inserted through the endoscope for further tissue extraction in the same manner.

Claim 1:
A biopsy forceps device (<NUM>), comprising:
a control member (<NUM>) extending from a proximal end to a distal end;
a yoke (<NUM>) coupled to a distal end of the control member, the yoke including a tissue contacting structure extending distally from a distal end of the yoke, wherein the tissue contacting structure is formed as a tissue penetrating spike (<NUM>);
first and second jaws (<NUM>, <NUM>) coupled to the yoke, the first and second jaws being biased toward an open configuration, in which the jaws are separated from one another to receive target tissue therebetween and being moveable to a closed configuration, in which cutting edges of the jaws are moved toward one another to cut a portion of the target tissue from surrounding tissue, the first and second jaws defining a tissue receiving space (<NUM>) therebetween to house the cut tissue; and
a capsule (<NUM>) slidably receiving the yoke and a proximal portion of each of the first and second jaws, the first and second jaws being constrained to the closed configuration when withdrawn proximally to a first position within the capsule, and the first and second jaws being configured so that, when the first and second jaws are moved to a second position distal of the first position, distal portions of the jaws are freed from the constraint of the capsule and spread apart from one another under their natural bias to the open configuration, the tissue contacting structure being positioned so that, when the yoke and the first and second jaws are moved distally and the first and second jaws move to the open configuration, the tissue contacting structure extends distally to engage a portion of tissue between the first and second jaws to anchor the engaged portion of tissue against lateral movement as the first and second jaws contact the tissue adjacent to the engaged portion of tissue,
characterized in that the control member is non-rotatably coupled to the yoke and the yoke and the first and second jaws are rotatably received within the capsule so that, rotation of the control member rotates the yoke and the first and second jaws within the capsule.