Proximal actuation handle for a biopsy forceps instrument having irrigation and aspiration capabilities

An embodiment of the invention includes an assembly for collecting tissue samples. The assembly includes a sample tray holder having a first connector configured to be placed in communication with a first aspiration tube, a second connector configured to be placed in communication with a second aspiration tube, and a sample tray defining a plurality of sample chambers. Each of the plurality of sample chambers includes a first opening configured to be placed in communication with the first connector, a second opening configured to be placed in communication with the second connector, and a sample catch member disposed between the first and second openings, the sample catch member configured to permit a fluid to pass therethrough.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates broadly to endoscopic surgical instruments. More particularly, this invention relates to an actuation handle for an endoscopic biopsy forceps instrument with means for facilitating sample removal without withdrawal of the biopsy forceps instrument from an endoscope.

2. State of the Art

Endoscopic biopsy procedures are typically performed with an endoscope and an endoscopic biopsy forceps device (bioptome). The endoscope is a long flexible tube carrying fiber optics and having a narrow lumen through which the bioptome is inserted. The bioptome typically includes a long flexible coil having a pair of opposed jaws at the distal end and manual actuation means at the proximal end. Manipulation of the actuation means opens and closes the jaws. During a biopsy tissue sampling operation, the surgeon guides the endoscope to the biopsy site while viewing the biopsy site through the fiber optics of the endoscope. The bioptome is inserted through the narrow lumen of the endoscope until the opposed jaws arrive at the biopsy site. While viewing the biopsy site through the fiber optics of the endoscope, the surgeon positions the jaws around a tissue to be sampled and manipulates the actuation means so that the jaws close around the tissue. A sample of the tissue is then cut and/or torn away from the biopsy site while it is trapped between the jaws of the bioptome. Keeping the jaws closed, the surgeon withdraws the bioptome from the endoscope and then opens the jaws to collect the biopsy tissue sample.

A biopsy tissue sampling procedure often requires the taking of several tissue samples either from the same or from different biopsy sites. Unfortunately, most bioptomes are limited to taking a single tissue sample, after which the device must be withdrawn from the endoscope and the tissue collected before the device can be used again to take a second tissue sample. Several attempts have been made to provide an instrument which will allow the taking of several tissue samples before the instrument must be withdrawn and the samples collected. Problems in providing such an instrument include the extremely small size required by the narrow lumen of the endoscope and the fact that the instrument must be flexible in order to be inserted through the lumen of the endoscope. Thus, several known multiple sample biopsy instruments are precluded from use with an endoscope because of their size and rigidity. These include the “punch and suction type” instruments disclosed in U.S. Pat. No. 3,989,033 to Halpern et al. and U.S. Pat. No. 4,522,206 to Whipple et al. Both of these devices have a hollow tube with a punch at the distal end and a vacuum source coupled to the proximal end. A tissue sample is cut with the punch and suctioned away from the biopsy site through the hollow tube. It is generally recognized, however, that dry suctioning tissue samples (i.e., without the use of an irrigating fluid) through a long narrow flexible bioptome is virtually impossible.

Efforts have been made to provide multiple sampling ability to an instrument which must traverse the narrow lumen of an endoscope. These efforts have concentrated on providing a cylindrical storage space at the distal end of the instrument wherein several tissue samples can be accumulated before the instrument is withdrawn from the endoscope. U.S. Pat. No. 4,651,753 to Lifton, for example, discloses a rigid cylindrical member attached to the distal end of a first flexible tube. The cylindrical member has a lateral opening and a concentric cylindrical knife blade is slidably mounted within the cylindrical member. A second flexible tube, concentric to the first tube is coupled to the knife blade for moving the knife blade relative to the lateral opening in the cylindrical member. A third flexible tube having a plunger tip is mounted within the second flexible tube and a vacuum source (a syringe) is coupled to the proximal end of the third tube. A tissue sample is taken by bringing the lateral opening of the cylindrical member upon the biopsy site, applying vacuum with the syringe to draw tissue into the lateral opening, and pushing the second flexible tube forward to move the knife blade across the lateral opening. A tissue sample is thereby cut and trapped inside the cylindrical knife within the cylindrical member. The third flexible tube is then pushed forward moving its plunger end against the tissue sample and pushing it forward into a cylindrical storage space at the distal end of the cylindrical member. Approximately six samples can be stored in the cylindrical member, after which the instrument is withdrawn from the endoscope. A distal plug on the cylindrical member is removed and the six samples are collected by pushing the third tube so that its plunger end ejects the samples.

The device of the Lifton patent suffers from several recognizable drawbacks. First, it is often difficult to obtain a tissue sample laterally of the device. Second, in order to expedite the obtaining of a lateral sample, a syringe is used to help draw the tissue into the lateral opening. However, this causes what was once a two-step procedure (position and cut), to become a three-step procedure (position, suction, cut). In addition, the use of a syringe requires an additional hand. Third, the Lifton patent adds a fourth step to the biopsy procedure by requiring that the tissue sample be pushed into the storage space. Thus, in all, the Lifton patent requires substantial effort on the part of the surgeon and an assistant and much of this effort is involved in pushing tubes, an action which is counter-intuitive to classical biopsy sampling. The preferred mode of operation of virtually all endoscopic tools is that a gripping action at the distal end of the instrument is effected by a similar action at the proximal end of the instrument. Classical biopsy forceps jaws are closed by squeezing a manual actuation member in a syringe-like manner.

A more convenient endoscopic multiple sample biopsy device is disclosed in U.S. Pat. No. 5,171,255 to Rydell. Rydell provides a flexible endoscopic instrument with a knife-sharp cutting cylinder at its distal end. A coaxial anvil is coupled to a pull wire and is actuated in the same manner as conventional biopsy forceps. When the anvil is drawn into the cylinder, tissue located between the anvil and the cylinder is cut and pushed into a storage space within the cylinder. Several samples may be taken and held in the storage space before the device is withdrawn from the endoscope. While the device of Rydell is effective in providing a multiple sample tool where each sample is obtained with a traditional two-step procedure (position and cut), it is still limited to lateral cutting which is often problematic. Traditional biopsy forceps provide jaws which can grasp tissue frontally or laterally. Even as such, it is difficult to position the jaws about the tissue to be sampled. Lateral sampling is even more difficult.

A multiple sample biopsy forceps of a more traditional form is disclosed in co-owned U.S. Pat. No. 5,542,432 to Slater et al. Slater et al. discloses an endoscopic multiple sample biopsy forceps having a jaw assembly which includes a pair of opposed toothed jaw cups each of which is coupled by a resilient arm to a base member. The base member of the jaw assembly is mounted inside a cylinder and axial movement of one of the jaw assembly and cylinder relative to the other draws the arms of the jaws into the cylinder or moves the cylinder over the arms of the jaws to bring the jaw cups together in a biting action. The arms of the jaws effectively form a storage chamber which extends proximally from the lower jaw cup and prevents accumulated biopsy samples from being squeezed laterally out from between the jaws during repeated opening and closing of the jaws and the lower jaw cup enhances movement of the biopsy samples into the storage chamber. The device can hold up to four samples before it must be retrieved out of the endoscope. However, in some biopsy procedures it is sometimes desirous to retrieve more. In addition, it has been found that samples within the chamber can stick together and make determinations of which sample came from which biopsy site somewhat difficult.

U.S. Pat. No. 5,538,008 to Crowe discloses a multiple sample bioptome which purports to take several samples and to transfer each sample by water pressure through a duct to the proximal end of the instrument, where each sample can be individually retrieved. The device includes a plastic jaw set biased in an open position and coupled to the distal end of an elongate tube, up to seven feet long. The tube defines a duct. A sleeve extends over the tube and a water flow passage is provided between the tube and the sleeve. An aperture is provided in the tube to permit the water flow passage to meet the duct at the distal end of the tube. Withdrawing the tube into the sleeve is disclosed to force the jaws closed and enable a sample to be cut from tissue and lodge in the duct. The water flow passage is disclosed to enable water to flow under pressure from the proximal end of passage to the distal end of the passage, through the aperture and into the distal end of the duct and to be aspirated to the proximal end of the duct, thereby transferring with it any sample contained in the duct to the proximal end where the sample can be retrieved.

While on paper the Crowe device is appealing, in practice the design is impractical and flawed. For example, it would be very difficult, if not impossible, to slide the elongate tube, up to seven feet in length, relative to a sleeve of substantially the same length. It would also be difficult to maintain an unobstructed water flow passage between the tube and sleeve as the tube and sleeve curve and bend through the body. Furthermore, in order for the jaws to cut a tissue sample, the tube and jaws must be drawn into the sleeve, thereby undesirably pulling the jaws away from the tissue to be sampled.

SUMMARY OF THE INVENTION

It is therefore an object of the invention to provide an endoscopic biopsy forceps instrument which permits numerous tissue samples to be taken from a patient without removing the forceps from within the patient.

It is another object of the invention to provide an endoscopic biopsy forceps instrument which can individually retrieve each of several tissue samples from the forceps without removing the forceps from the patient.

It is also an object of the invention to provide an endoscopic biopsy forceps instrument which irrigates the forceps and aspirates tissue samples contained therein.

It is an additional object of the invention to provide an endoscopic biopsy forceps instrument which includes a proximal actuation handle having a chamber to retain tissue samples aspirated through the instrument.

It is a further object of the invention to provide an endoscopic biopsy forceps instrument which includes a proximal actuation handle for an endoscopic biopsy forceps instrument which includes a control means for controlling the aspiration and irrigation of fluid through the instrument.

In accord with these objects which will be discussed in detail below, an endoscopic biopsy forceps instrument is provided and generally includes a proximal actuation handle, a distal forceps assembly, a control member coupled to the proximal actuation handle and the distal forceps assembly, and a flexible multi-lumen tubular member having an irrigation conduit, an aspiration conduit, and a control conduit which receives the control member.

According to a preferred embodiment of the invention, the proximal actuation handle includes a shaft and a spool slidably mounted on the shaft. The actuation handle is also provided with a proximal irrigation passage, a sample chamber, a sample catch member, and a pinch valve which regulates irrigation and aspiration. The proximal irrigation passage is coupled to the irrigation conduit and to an irrigation coupling tube. The sample chamber is coupled to the aspiration conduit and to an aspiration coupling tube. The sample catch member includes a screen which is inserted into the sample chamber and filters out tissue samples from the aspirated fluid. The irrigation coupling tube and the aspiration coupling tube extend through the pinch valve which operates to control the flow of fluid through the tubes. The actuation handle is coupled to the proximal ends of both the flexible tubular member and the control member and moves the control member relative to the tubular member.

The distal assembly is coupled to the distal end of the tubular member and includes a hollow jaw cup coupled over the distal end of the aspiration conduit and a hollow movable jaw pivotally coupled adjacent the irrigation conduit. The jaw cup is preferably formed from a hard plastic and has a blunt cutting surface, while the movable jaw is preferably a metal jaw with a sharp cutting edge. The movable jaw is further coupled to the control member, such that actuation of the actuation handle moves the movable jaw relative to the jaw cup, and thereby moves the jaws from an open position to a closed position. Moving the hollow jaws to a closed position provides a substantially fluidtight coupling between the irrigation and aspiration conduits.

It will be appreciated that the distal end of the instrument is brought into contact with tissue of which a sample is required and the actuation handle is actuated to close the jaws and cut off a tissue sample. With the jaws in a closed position, water is irrigated through the irrigation conduit to the jaws at the distal end of the instrument and aspirated from the jaws to the proximal end of the instrument through the aspiration conduit, such that the sample cut by the jaws is aspirated with the water. As the water is aspirated it passes through the chamber and the sample is filtered onto the screen. The screen may easily be removed to retrieve the sample. It will be further appreciated that the entire procedure of cutting a sample and retrieving the sample may be performed without removing the endoscopic biopsy forceps instrument from its location within the body.

According to one embodiment of the biopsy forceps instrument, the tubular member is ovoid in shape and defines a control conduit, an irrigation conduit, and an aspiration conduit. The distal forceps assembly includes a movable jaw, and a substantially rigid molded collar which is provided with a proximal socket-like coupling means for coupling the tubular member thereto, a fixed jaw cup, a distal irrigation passage, and a control passage. The collar is of similar diameter to the endoscope and is designed to be coupled to the outside of the distal end of an endoscope by a silicone rubber sock. The movable jaw is pivotally mounted on the molded collar and is movable relative to jaw cup. The tubular member is coupled in the socket. A control wire extends through the control conduit and the control passage is coupled to the two holes in the movable jaw.

According to a second embodiment, the biopsy forceps instrument includes a tubular member which defines an aspiration conduit having a circular cross section, an irrigation conduit having a kidney-shaped cross section, and two control conduits. The distal assembly includes a stationary jaw bonded to the distal end of the tubular member, and a movable jaw. The stationary jaw includes a hollow jaw cup, a clevis member and two proximal ramps. The jaw cup is located over the aspiration conduit, and the clevis and the proximal ramps extend from the jaw cup over the irrigation conduit. The movable jaw is coupled to the clevis and is guided along the proximal ramps. The two control conduits exit the distal end of the tubular member lateral of the proximal ramps. A central portion of a control member is coupled to the movable jaw and each end of the control member extends through the control conduits to the proximal end of the instrument.

According to a third embodiment of the biopsy forceps instrument, the instrument includes a tubular member which defines an aspiration conduit having a circular cross section and an irrigation conduit having a crescent-shaped cross section. The distal assembly is substantially similar to the second embodiment. The proximal ramps abut and partially cover the irrigation conduit to define two entrances into the irrigation conduit for the control members. A distal end of each control member is coupled to the movable jaw and the control members extend through the entrances and into the irrigation conduit. The entrances are sufficiently small such that when the jaws are in a closed position and fluid is irrigated through the irrigation conduit to the distal assembly, substantially all of the fluid passes through the irrigation conduit and into the jaws; i.e. only an insubstantial amount of the fluid irrigated through the irrigation conduit exits through the entrances formed by the ramps.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Turning now toFIG. 1, a multiple sample biopsy forceps instrument10is shown. The biopsy forceps instrument generally includes a proximal actuation handle12, a flexible multi-lumen tubular member14, a pull wire20, and a distal assembly22. Several coupling tubes are preferably provided to couple the proximal actuation handle12to the tubular member14and to irrigation and aspiration means. In particular, a control coupling tube23, first and second irrigation coupling tubes24,25and first and second aspiration coupling tubes26,27are provided.

The proximal actuation handle12includes a shaft30having a transverse slot32and a spool34slidably mounted on the shaft and having a transverse bar (not shown) extending through the slot32, as is common in the art. The actuation handle12is provided with a pinch valve45which regulates irrigation and aspiration and a sample catch assembly41which includes a sample chamber42and a sample catch member44. Turning toFIGS. 2 and 3, the sample chamber42includes irrigation connectors46,47which couple the first irrigation coupling tube24to the second irrigation coupling tube25. The sample chamber42also includes first and second aspiration connectors48,49which couple the first aspiration coupling tube26to the second aspiration coupling tube27. As shown inFIG. 3, the diameter of the chamber42is significantly larger than the diameter of the first (and second) aspiration coupling tubes26(,27). As also shown inFIG. 3, the chamber42includes a sample catch connector43for removably coupling the chamber to a distal portion of the shaft30. The sample catch connector43is preferably T-shaped for mating with a slot (not shown) on the shaft30, but may be otherwise shaped for connection to the shaft. Referring toFIGS. 3 through 5, the sample catch member44includes a handle portion52, an engagement portion54which removably engages the sample catch member44to the sample chamber42, and a screen56. The screen56extends through the sample chamber42between the first and second aspiration connectors48,49. The screen56includes a front side58and a back side60and is provided with a plurality of perforations62which are preferably frustoconical in shape and expand from the front side58to the back side60. As further shown inFIGS. 3 through 5, the engagement portion54and the opening of the sample chamber42preferably have irregular shaped cross-sections which enable the engagement of the engagement portion54into the sample chamber42in one orientation only. As a result, the frustoconical perforations62of the screen56can be easily aligned in the proper front to back orientation.

As shown inFIG. 2, the first irrigation coupling tube24and the first aspiration coupling tube26extend through the pinch valve45which operates to control the flow of fluid through the tubes24,26. The pinch valve is biased to clamp closed the first irrigation coupling tube24and the first aspiration coupling tube26, i.e, to collapse the tubes on top of each other. Pressing downward on the pinch valve45with a practitioner's finger counters the bias of the pinch valve to permit fluid flow through the first irrigation coupling tube24and the first aspiration coupling tube26.

Turning toFIGS. 6 and 7, and in accord with the first embodiment of the invention, the tubular member14is preferably an ovoid multi-lumen extrusion. The tubular member includes a proximal end66, a distal end68, a control conduit70, an irrigation conduit72, and an aspiration conduit74, each of which extends through the tubular member to the distal assembly22. At the proximal end66of the tubular member, the control conduit70is coupled to the control coupling tube23, the irrigation conduit72is coupled to the second irrigation coupling tube25and the aspiration conduit74is coupled to the second aspiration coupling tube27.

Referring toFIGS. 7 through 9, the distal assembly22includes a substantially rigid molded collar80and a hollow movable jaw90. The collar80is preferably made from a unitary piece of polycarbonate, a glass-filled polycarbonate, a hard grade styrene, or other plastic, while the movable jaw90is preferably made from cast metal. The collar includes a central opening81, a circumferential channel83, a distally extending control passage82, a distally extending hollow jaw mount84, a distally extending hollow stationary jaw88, and a proximal socket86. The central opening81of the collar80is of similar diameter to the outer diameter of the endoscope and is designed to couple the collar to the outside of the distal end of an endoscope. The circumferential channel81receives a portion of a silicone rubber sock (not shown), which is used to secure the collar80to the endoscope.

The stationary jaw88preferably includes a blunt edge or lip92. The movable jaw90is pivotally mounted at a pivot94on the jaw mount84and is pivotable relative to stationary jaw88. The movable jaw90is preferably provided with a sharp cutting edge98, a stop100for limiting the extent to which the movable jaw pivots away from the stationary jaw88, and two jaw holes102,104, for receiving a pull wire20, as described below.

Referring toFIGS. 9 through 11, the proximal socket86is aligned with the control passage82, the jaw mount84and the stationary jaw88, and is designed to receive the distal end68of the flexible tubular member14. The distal end68of the tubular member is secured in the proximal socket86, preferably using an adhesion bonding agent, such that the control passage82is coupled to the control conduit70, the jaw mount84is coupled substantially fluidtight to the irrigation conduit72, and the stationary jaw88is coupled substantially fluidtight to the aspiration conduit74.

Turning back toFIGS. 1,6,7and10, a central portion of the pull wire20extends through the jaw holes102,104and the ends of the pull wire20extend through the control passage82, the control conduit70, and the control coupling tube23to the spool34. Referring toFIG. 12, alternatively the pull wire20aforms a secure loop106athrough the jaw holes102a,104aby doubling back on itself and forming a twist108a. Referring toFIG. 13, in yet another alternative, two pull wires20b,21bmay be used, the distal end of each pull wire being coupled to a jaw hole102b,104bby a Z-bend110b,112band extending through the control passage82b.

Referring toFIGS. 1,7, and8, it will be appreciated that movement of the spool34relative to the shaft30results in movement of the pull wire20relative to the tubular member14and consequently moves the movable jaw90relative to the stationary jaw88such that the jaws open (FIG. 7) and close (FIG. 8). Referring toFIGS. 7 through 11, when the stationary and movable jaws88,90are in a closed position a substantially fluidtight passage is formed therebetween. Because the stationary jaw88is coupled to the aspiration conduit74and the movable jaw90is coupled over the irrigation conduit72, a substantially fluidtight coupling of the irrigation and aspiration conduits is achieved.

In use, it will be appreciated that the distal end of the endoscope to which the collar80is coupled is maneuvered adjacent the desired tissue for sampling and the distal assembly is brought into contact with tissue110(FIGS. 10 and 11). The actuation handle12is actuated to close the jaws88,90and cut off a tissue sample112. When the jaws88,90are in a closed position, the irrigation means and the aspiration means are activated and the first proximal irrigation coupling tube and the first proximal aspiration coupling tube24,26are released from the clamping action of the pinch valve45by depressing the pinch valve. Irrigating fluid is thereby permitted to flow through the first and second proximal irrigation coupling tubes24,26, through the irrigation conduit72and the hollow jaw mount84, and to the jaws88,90at the distal end of the instrument. The fluid flows through the jaws and is aspirated back to the proximal end of the instrument such that the sample held within the jaws is aspirated with the water. Turning back toFIGS. 2 through 6, as the water is aspirated through the aspiration conduit74and into the sample chamber42, the sample is filtered onto the screen58. The frustoconical shape of the perforations62permits increased fluid flow through the perforate screen while preventing the tissue sample from passing through the screen. Irrigation and aspiration means are interrupted by releasing the pinch valve45such that the pinch valve clamps down on the first proximal irrigation and aspiration coupling tubes24,26and causes the tubes to collapse on top of each other. The screen58may easily be removed to retrieve the sample by gripping the handle portion52of the sample catch member44and pulling the sample catch member from the sample chamber42. The sample is recovered from the screen, and the sample catch member is reinserted into the sample chamber to continue the procedure. It will be further appreciated that the entire procedure of cutting a sample and retrieving the sample may be performed without removing the endoscopic multiple sample biopsy forceps instrument from its location within the body. Unlimited subsequent samples may be obtained in an identical manner.

A second embodiment of the proximal actuation handle is also provided, substantially similar to the first embodiment. Referring toFIGS. 14 to 18, the second embodiment has an alternate sample catch assembly900able to receive and keep separate samples without necessitating the removal of a sample catch between each sample retrieval. The sample catch assembly900generally includes a sample tray holder902having front and rear walls908,910, a sample tray904situated in the tray holder between the front and rear walls, and a threaded connector906extending through the front wall908of the tray holder902and the tray904and removably threaded into the rear wall. The tray904is rotatable about the threaded connector906and relative to the tray holder902. The threaded connector preferably includes an enlarged head912for easier manipulation by a practitioner's fingers.

The front wall908of the tray holder902includes a first bore916(seeFIG. 16) through which extends the threaded connector906, an inside surface917, and a first aspiration connector918which extends through the front wall908to the inside surface917. The rear wall910is provided with a second bore920, preferably threaded, into which the threaded connector906is secured, and a sample catch connector926which removably couples the sample catch assembly900to a distal portion of the shaft30. The rear wall is also provided with an inside surface921, a second aspiration connector922, and a proximal aspiration conduit924extending from the inside surface921to the second aspiration connector922. The tray holder902is also preferable provided with irrigation connectors914,915which couple the first irrigation coupling tube24to the second irrigation coupling tube25.

The tray904, preferably polygonally shaped, includes an axial bore927and a plurality of chambers or cups928a–h(indexed1through8, respectively, inFIG. 18). Referring toFIGS. 16 and 18, each cup928a–hhas a filter or screen930a–hand tapers to an outlet932a–h(932a,932eshown inFIG. 16) proximal of the screen. The screen preferably has frustoconical perforations. The tray904is rotatable within the tray holder902such that each of the cups928a–his positionable between the first aspiration connector918and the proximal aspiration conduit924for receiving a tissue sample. The cups928a–hare maintained in position by providing indentations934a–hin the tray904which receives a protruberance935on the inside surface921of the rear wall910(seeFIGS. 15 and 17); i.e., a cup (for example,928a) is held is position until sufficient force is provided to the tray904to rotate the tray and thereby position the next cup (for example,928b) for receiving a tissue sample. Each of the cups may thereby be positioned to receive a tissue sample without necessitating the removal of a screen between retrieving individual tissue samples. Alternatively, or in conjunction with the indentations934a–hand the protruberance935, a ratchet mechanism (not shown) can be provided to prevent rotation of a tray opposite to a predetermined direction. Preferably a stop936is also provided on the tray904to prevent the tray from being rotated through more than one cycle without first retrieving the samples received in the cups; i.e., to prevent contamination of an earlier retrieved sample by a later retrieved sample. The tray is also preferably provided with indicia938to indicate to the practitioner which cup is currently positioned to receive a sample.

After an individual sample has been received into a first cup, according to a similar method as described above with respect to the first embodiment, the aspiration and irrigation are interrupted and the tray904is rotated such that the next cup is positioned between the first aspiration connector918and the proximal aspiration conduit924. The process is repeated after each sample is received into a cup. Once the practitioner has obtained all of the desired samples, or once each cup of the tray contains a sample, the threaded connector906is uncoupled and the tray is removed and the samples may be removed from the cups of the tray. Index numbers adjacent the cups indicate the order in which the samples were retrieved.

Turning toFIGS. 19 and 20, a third embodiment of a multiple sample biopsy forceps instrument210is shown. The instrument includes a proximal actuation handle212, a flexible multi-lumen tubular member214, a pull wire220, and a distal assembly222. Several coupling tubes are preferably provided to couple the proximal actuation handle212to the tubular member214and to irrigation and aspiration means. In particular, a Y-shaped control coupling tube223, first and second irrigation coupling tubes224,225, and first and second aspiration coupling tubes226,227are provided.

The proximal actuation handle212is substantially similar to the first embodiment (with like parts having numbers incremented by200). Referring toFIGS. 20,21and22, the tubular member214is preferably a multi-lumen multi-layer extrusion, and preferably includes a first metal braid276beneath the outermost layer to add desired stiffness to the tubular member. If desired, a second metal braid277may be additionally provided around the aspiration conduit274to stiffen and support the aspiration conduit274. The tubular member214has a proximal end266, a distal end268, two control conduits270,271, an irrigation conduit272, and an aspiration conduit274, each of the conduits270,271,272,274extending through the tubular member to the distal assembly222. The aspiration conduit274has a substantially circular cross section. The irrigation conduit272has a generally kidney-shaped cross section and is separated from the aspiration conduit274by a membrane275. The control conduits270,271are preferably situated one on either end of the membrane275.

Referring toFIGS. 22 through 25, the distal assembly222according to the third embodiment of the invention includes a stationary jaw281coupled, preferably by adhesion bonding, to the distal end268of the tubular member. The stationary jaw281, preferably made of plastic, includes a jaw cup288, an integral central clevis293and integral proximal ramps295,296. The jaw cup288is located over the aspiration conduit274and preferably has a blunt cutting surface or lip292. The central clevis293and proximal ramps295,296extend from the stationary jaw281and abut and partially cover the irrigation conduit. A movable jaw290, preferably made of metal, is provided with a sharp cutting edge298, defines two jaw holes302,304for receiving a pull wire220, and is provided with two bosses312,314for mounting the jaw. The bosses312,314loosely engage the central clevis293and a pivot pin294extends through the bosses and the central clevis. The ramps295,296of the stationary jaw281guide the movable jaw290when opening and closing and assist to form a substantially fluidtight passage between the movable jaw290and the stationary jaw cup288when the jaws are in a closed position. A central portion of the pull wire220which is perpendicular to the longitudinal axis of the instrument extends through the jaw holes302,304and the ends of the pull wire extend into the control conduits270,271. Turning back toFIG. 20, the Y-shaped coupling tube223facilitates alignment of the ends of the pull wire220for coupling the pull wire to the proximal actuation handle. The pull wire220may be coated, e.g., in a plastic, to inhibit the pull wire from cutting into the tubular member.

Referring toFIGS. 23 and 25, the distal end268of the tubular member is inserted through the lumen of an endoscope to a biopsy site. The jaws288,290are moved into a closed position cutting off a tissue sample and further providing a substantially fluidtight coupling between the irrigation and aspiration conduits272,274. While it appears from the illustrations ofFIGS. 23 and 25that the irrigation conduit272is obstructed at the distal end by clevis293, it will be appreciated that the irrigation conduit272is substantially wider than the clevis and that fluid may flow around the clevis to the aspiration conduit274.

Turning now toFIGS. 26 through 28, a fourth embodiment of a multiple sample biopsy forceps, substantially similar to the third embodiment (with like parts having numbers incremented by another 200) is shown. The tubular member414has a proximal end466, a distal end468, an irrigation conduit472, and an aspiration conduit474. The aspiration conduit474has a substantially circular cross section, while the irrigation conduit472has a generally crescent-shaped cross section. A control coupling tube423is coupled to the second irrigation coupling tube425. Two pull wires420,421extend through the control coupling tube423, pass through a substantially fluidtight valve (not shown) coupling the control coupling tube423and the second irrigation coupling tube425, enter into the second irrigation coupling tube425, and extend through the irrigation conduit472to the distal end468of the tubular member. An aspiration coupling tube427is coupled to the aspiration conduit474.

Referring toFIG. 28, the distal assembly422of the fourth embodiment of the invention includes a stationary jaw481bonded to the distal end468of the tubular member and a movable jaw490coupled thereto. The stationary jaw481includes a jaw cup488, an integral central clevis493, and ramps495,496. The jaw cup abuts the distal end of the tubular member and is positioned over the aspiration conduit474and preferably has a blunt cutting surface or lip492. The central clevis493and ramps495,496extend from the stationary jaw481and abut and partially cover the irrigation conduit474. A movable jaw490, preferably made of metal, is provided with a sharp cutting edge498, defines two jaw holes402,404for receiving a pull wire420, and is provided with two bosses512,514for mounting the jaw. The bosses512,514loosely engage the central clevis493and a pivot pin494extends through the bosses and the central clevis. By partially covering the irrigation conduit, the ramps form entrances499,500for the pull wires. The movable jaw490rides on the proximal ramps495,496when moving from an open to a closed position. The pull wires420,421are coupled to the jaw holes502,504by a Z-bend506,507and extend through the entrances499,500into the irrigation conduit472, through a portion of the second irrigation coupling tube425, and further into a control coupling tube423coupled thereto. The entrances499,500are sufficiently small that only an insubstantial amount of fluid exits from the irrigation conduit when the jaws are in a closed position and irrigant is forced through the irrigation conduit474to the distal assembly.

Turning toFIG. 29, a fifth embodiment of the invention, substantially similar to the fourth embodiment (with like parts having numbers incremented by200) is shown. The tubular member614is preferably a multi-lumen extrusion co-extruded with support wires676,677,678. The tubular member614has two irrigation conduits672,673, and an aspiration conduit674. The aspiration conduit674has a substantially circular cross section, and the irrigation conduits672,673have a generally ovoid cross section. The extrusion is preferably made of a polymer (e.g., polyurethane, a polyether block amide, polyethylene, or PVC) or another bondable material. A pull wire620,621extends through each irrigation conduit672,673. By way of example, the preferred diameter for the tubular member614is approximately 2.8–3.3 mm, the preferred diameter for the aspiration conduit674is approximately 1.5 mm, and the preferred diameter for each of the support wires676,677,678is approximately 0.4 mm. The support wires are preferably made of stainless steel and are also preferably round, but alternatively may be flat. The tubular member of the fifth embodiment is incorporated into the invention in a manner substantially similar to the tubular member of the fourth embodiment and several advantages are realized with this embodiment. First, a three support wire co-extrusion provides necessary rigidity to the wall of the aspiration conduit. Second, the three wire co-extrusion is easy to manufacturer.

Turning toFIG. 30, it will be further appreciated that the three support wires may be replaced with a single larger high tensile support wire676aor multiband cable through the tubular member614a. The support wire is preferably located substantially between the two irrigation conduits and the aspiration conduit. The single support wire676aprovides necessary support to the aspiration conduit674aand is also easy to manufacture. Moreover, the entire support wire or just its distal end may be made from a shape memory material, e.g., Nitinol, which will bend in a predetermined manner when heated to a predetermined temperature. As a result, by heating the support wire to a predetermined temperature, e.g., by applying a current thereto, the shape memory distal end of the support wire can be made to bend in a predetermined manner and consequently the tubular member can be made to bend in a predetermined manner. Tissue samples can thereby be retrieved which are not linearly aligned with the endoscope through which the distal end of the biopsy forceps instrument extends.

There have been described and illustrated herein several embodiments of a multiple sample endoscopic biopsy instrument. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. Therefore, while a particular manner of coupling the proximal actuation handle to the tubular member has been disclosed for the several embodiments, it will be appreciated that other manners of coupling the proximal and distal assemblies may be used as well. In addition, while a pinch valve is described for regulating aspiration and irrigation through the tubular member, it will be appreciated that other valve means may likewise be used to the same effect. Also, it will be appreciated that separate valve means may be provided to individually control aspiration and irrigation. It will also be appreciated that while the valve means has been shown coupled to the proximal actuation handle, the valve means may be separable and/or independent from the proximal actuation handle. Furthermore, while the chamber has been described as being removably coupled to the shaft, it will be appreciated that the chamber may be integral with the shaft or, alternatively, not coupled to the actuation handle. Moreover, the shapes of the chamber and the catch member may be different from that described. In addition, it is not necessary to provide first and second irrigation connectors as a single uninterrupted coupling tube may extend from the irrigation conduit of the tubular member through the valve means. Furthermore, while a spool and shaft type actuation means has been disclosed which moves the pull wire(s) relative to the tubular member, it will be appreciated that the actuation means may be of another type well known in the art. For example, a laparoscopic type handle (scissor-type) may also be used. It will therefore be appreciated by those skilled in the art that yet other modifications could be made to the provided invention without deviating from its spirit and scope as so claimed.