Abstract:
An embodiment of the invention includes a medical device. The device includes a proximal handle coupled to the proximal end of an elongated member, and a distal assembly coupled to the distal end of the elongated member. The device also includes a collar coupled to the distal assembly proximate to the distal assembly. The collar is adapted to couple the distal assembly to a medical instrument.

Description:
This application is a continuation of application Ser. No. 10/885,021, filed Jul. 7, 2004 now U.S. Pat. No. 7,204,811, of Juergen Andrew KORTENBACH et al. for Proximal Actuation Handle For A Biopsy Forceps Instrument Having Irrigation And Aspiration Capabilities, currently pending, which is a continuation of application Ser. No. 10/228,278, filed Aug. 27, 2002 (now U.S. Pat. No. 6,832,990); which is a continuation of application Ser. No. 09/599,403, filed Jun. 22, 2000 (now U.S. Pat. No. 6,544,194); which is a divisional of application Ser. No. 08/794,352, filed Feb. 3, 1997 (now U.S. Pat. No. 6,142,956); which is a continuation-in-part of application Ser. No. 08/756,260, filed Nov. 25, 1996 (now U.S. Pat. No. 5,897,507), all of which are hereby incorporated by reference in their entirety herein. 
    
    
     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. 
     Additional objects and advantages of the invention will become apparent to those skilled in the art upon reference to the detailed description taken in conjunction with the provided figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a broken perspective view of a first embodiment of an endoscopic biopsy forceps instrument according to the invention; 
         FIG. 2  is a broken perspective view of the proximal end of the first embodiment of the invention; 
         FIG. 3  is a broken perspective view of the sample chamber of the first embodiment of the invention; 
         FIG. 4  is a perspective view of the front side of the sample catch member of the first embodiment of the invention; 
         FIG. 5  is a perspective view of the back side of the sample catch member of the first embodiment of the invention; 
         FIG. 6  is an enlarged broken perspective view of the tubular member of the first embodiment of the invention; 
         FIG. 7  is an enlarged broken perspective view of the distal assembly of the first embodiment of the invention with the jaws in an open position; 
         FIG. 8  is an enlarged broken perspective view of the distal assembly of the first embodiment of the invention with the jaws in a closed position; 
         FIG. 9  is a bottom end view of  FIG. 8 ; 
         FIG. 10  is a cross section across line  10 - 10  of  FIG. 7 ; 
         FIG. 11  is cross section across line  11 - 11  of  FIG. 8 ; 
         FIG. 12  is a broken perspective view of the distal assembly of the first embodiment illustrating an alternate control member configuration; 
         FIG. 13  is a broken perspective view of the distal assembly of the first embodiment illustrating another alternate control member configuration; 
         FIG. 14  is a front elevation view of a sample catch assembly according to a second embodiment of the invention; 
         FIG. 15  is a top view of the sample catch assembly according to the second embodiment of the invention; 
         FIG. 16  is cross section view through line  16 - 16  in  FIG. 14 ; 
         FIG. 17  is a side elevation view of the sample catch assembly according to the second embodiment of the invention; 
         FIG. 18  is a front elevation view of the sample tray of the sample catch assembly according to the second embodiment of the invention; 
         FIG. 19  is a broken perspective view of a third embodiment of an endoscopic biopsy forceps instrument of the invention; 
         FIG. 20  is an enlarged broken transparent perspective view of the tubular member of the third embodiment of the invention; 
         FIG. 21  is an enlarged cross section across line  21 - 21  of  FIG. 20 ; 
         FIG. 22  is an enlarged broken perspective view of the distal assembly of the third embodiment of the invention with the jaws in an open position; 
         FIG. 23  is a cross section across line  23 - 23  of  FIG. 22 ; 
         FIG. 24  is an enlarged broken perspective view of the distal end of the third embodiment of the invention with the biopsy jaws in a closed position; 
         FIG. 25  is a cross section across line  25 - 25  of  FIG. 24 ; 
         FIG. 26  is an enlarged broken transparent perspective view of the tubular member of the fourth embodiment of the invention; 
         FIG. 27  is an enlarged cross-section across line  27 - 27  of  FIG. 26 ; 
         FIG. 28  is a enlarged broken perspective view of the distal end of a fourth embodiment of the invention with the jaws in an open position; 
         FIG. 29  is a cross-section of a tubular member according to a fifth embodiment of the invention; and 
         FIG. 30  is a cross-section of a tubular member according to a sixth embodiment of the invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Turning now to  FIG. 1 , a multiple sample biopsy forceps instrument  10  is shown. The biopsy forceps instrument generally includes a proximal actuation handle  12 , a flexible multi-lumen tubular member  14 , a pull wire  20 , and a distal assembly  22 . Several coupling tubes are preferably provided to couple the proximal actuation handle  12  to the tubular member  14  and to irrigation and aspiration means. In particular, a control coupling tube  23 , first and second irrigation coupling tubes  24 ,  25  and first and second aspiration coupling tubes  26 ,  27  are provided. 
     The proximal actuation handle  12  includes a shaft  30  having a transverse slot  32  and a spool  34  slidably mounted on the shaft and having a transverse bar (not shown) extending through the slot  32 , as is common in the art. The actuation handle  12  is provided with a pinch valve  45  which regulates irrigation and aspiration and a sample catch assembly  41  which includes a sample chamber  42  and a sample catch member  44 . Turning to  FIGS. 2 and 3 , the sample chamber  42  includes irrigation connectors  46 ,  47  which couple the first irrigation coupling tube  24  to the second irrigation coupling tube  25 . The sample chamber  42  also includes first and second aspiration connectors  48 ,  49  which couple the first aspiration coupling tube  26  to the second aspiration coupling tube  27 . As shown in  FIG. 3 , the diameter of the chamber  42  is significantly larger than the diameter of the first (and second) aspiration coupling tubes  26  (, 27 ). As also shown in  FIG. 3 , the chamber  42  includes a sample catch connector  43  for removably coupling the chamber to a distal portion of the shaft  30 . The sample catch connector  43  is preferably T-shaped for mating with a slot (not shown) on the shaft  30 , but may be otherwise shaped for connection to the shaft. Referring to  FIGS. 3 through 5 , the sample catch member  44  includes a handle portion  52 , an engagement portion  54  which removably engages the sample catch member  44  to the sample chamber  42 , and a screen  56 . The screen  56  extends through the sample chamber  42  between the first and second aspiration connectors  48 ,  49 . The screen  56  includes a front side  58  and a back side  60  and is provided with a plurality of perforations  62  which are preferably frustoconical in shape and expand from the front side  58  to the back side  60 . As further shown in  FIGS. 3 through 5 , the engagement portion  54  and the opening of the sample chamber  42  preferably have irregular shaped cross-sections which enable the engagement of the engagement portion  54  into the sample chamber  42  in one orientation only. As a result, the frustoconical perforations  62  of the screen  56  can be easily aligned in the proper front to back orientation. 
     As shown in  FIG. 2 , the first irrigation coupling tube  24  and the first aspiration coupling tube  26  extend through the pinch valve  45  which operates to control the flow of fluid through the tubes  24 ,  26 . The pinch valve is biased to clamp closed the first irrigation coupling tube  24  and the first aspiration coupling tube  26 , i.e, to collapse the tubes on top of each other. Pressing downward on the pinch valve  45  with a practitioner&#39;s finger counters the bias of the pinch valve to permit fluid flow through the first irrigation coupling tube  24  and the first aspiration coupling tube  26 . 
     Turning to  FIGS. 6 and 7 , and in accord with the first embodiment of the invention, the tubular member  14  is preferably an ovoid multi-lumen extrusion. The tubular member includes a proximal end  66 , a distal end  68 , a control conduit  70 , an irrigation conduit  72 , and an aspiration conduit  74 , each of which extends through the tubular member to the distal assembly  22 . At the proximal end  66  of the tubular member, the control conduit  70  is coupled to the control coupling tube  23 , the irrigation conduit  72  is coupled to the second irrigation coupling tube  25  and the aspiration conduit  74  is coupled to the second aspiration coupling tube  27 . 
     Referring to  FIGS. 7 through 9 , the distal assembly  22  includes a substantially rigid molded collar  80  and a hollow movable jaw  90 . The collar  80  is preferably made from a unitary piece of polycarbonate, a glass-filled polycarbonate, a hard grade styrene, or other plastic, while the movable jaw  90  is preferably made from cast metal. The collar includes a central opening  81 , a circumferential channel  83 , a distally extending control passage  82 , a distally extending hollow jaw mount  84 , a distally extending hollow stationary jaw  88 , and a proximal socket  86 . The central opening  81  of the collar  80  is 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 channel  81  receives a portion of a silicone rubber sock (not shown), which is used to secure the collar  80  to the endoscope. 
     The stationary jaw  88  preferably includes a blunt edge or lip  92 . The movable jaw  90  is pivotally mounted at a pivot  94  on the jaw mount  84  and is pivotable relative to stationary jaw  88 . The movable jaw  90  is preferably provided with a sharp cutting edge  98 , a stop  100  for limiting the extent to which the movable jaw pivots away from the stationary jaw  88 , and two jaw holes  102 ,  104 , for receiving a pull wire  20 , as described below. 
     Referring to  FIGS. 9 through 11 , the proximal socket  86  is aligned with the control passage  82 , the jaw mount  84  and the stationary jaw  88 , and is designed to receive the distal end  68  of the flexible tubular member  14 . The distal end  68  of the tubular member is secured in the proximal socket  86 , preferably using an adhesion bonding agent, such that the control passage  82  is coupled to the control conduit  70 , the jaw mount  84  is coupled substantially fluidtight to the irrigation conduit  72 , and the stationary jaw  88  is coupled substantially fluidtight to the aspiration conduit  74 . 
     Turning back to  FIGS. 1 ,  6 ,  7  and  10 , a central portion of the pull wire  20  extends through the jaw holes  102 ,  104  and the ends of the pull wire  20  extend through the control passage  82 , the control conduit  70 , and the control coupling tube  23  to the spool  34 . Referring to  FIG. 12 , alternatively the pull wire  20   a  forms a secure loop  106   a  through the jaw holes  102   a ,  104   a  by doubling back on itself and forming a twist  108   a . Referring to  FIG. 13 , in yet another alternative, two pull wires  20   b ,  21   b  may be used, the distal end of each pull wire being coupled to a jaw hole  102   b ,  104   b  by a Z-bend  110   b ,  112   b  and extending through the control passage  82   b.    
     Referring to  FIGS. 1 ,  7 , and  8 , it will be appreciated that movement of the spool  34  relative to the shaft  30  results in movement of the pull wire  20  relative to the tubular member  14  and consequently moves the movable jaw  90  relative to the stationary jaw  88  such that the jaws open ( FIG. 7 ) and close ( FIG. 8 ). Referring to  FIGS. 7 through 11 , when the stationary and movable jaws  88 ,  90  are in a closed position a substantially fluidtight passage is formed there between. Because the stationary jaw  88  is coupled to the aspiration conduit  74  and the movable jaw  90  is coupled over the irrigation conduit  72 , 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 collar  80  is coupled is maneuvered adjacent the desired tissue for sampling and the distal assembly is brought into contact with tissue  110  ( FIGS. 10 and 11 ). The actuation handle  12  is actuated to close the jaws  88 ,  90  and cut off a tissue sample  112 . When the jaws  88 ,  90  are 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 tube  24 ,  26  are released from the clamping action of the pinch valve  45  by depressing the pinch valve. Irrigating fluid is thereby permitted to flow through the first and second proximal irrigation coupling tubes  24 ,  26 , through the irrigation conduit  72  and the hollow jaw mount  84 , and to the jaws  88 ,  90  at 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 to  FIGS. 2 through 6 , as the water is aspirated through the aspiration conduit  74  and into the sample chamber  42 , the sample is filtered onto the screen  58 . The frustoconical shape of the perforations  62  permits 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 valve  45  such that the pinch valve clamps down on the first proximal irrigation and aspiration coupling tubes  24 ,  26  and causes the tubes to collapse on top of each other. The screen  58  may easily be removed to retrieve the sample by gripping the handle portion  52  of the sample catch member  44  and pulling the sample catch member from the sample chamber  42 . 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 to  FIGS. 14 to 18 , the second embodiment has an alternate sample catch assembly  900  able to receive and keep separate samples without necessitating the removal of a sample catch between each sample retrieval. The sample catch assembly  900  generally includes a sample tray holder  902  having front and rear walls  908 ,  910 , a sample tray  904  situated in the tray holder between the front and rear walls, and a threaded connector  906  extending through the front wall  908  of the tray holder  902  and the tray  904  and removably threaded into the rear wall. The tray  904  is rotatable about the threaded connector  906  and relative to the tray holder  902 . The threaded connector preferably includes an enlarged head  912  for easier manipulation by a practitioner&#39;s fingers. 
     The front wall  908  of the tray holder  902  includes a first bore  916  (see  FIG. 16 ) through which extends the threaded connector  906 , an inside surface  917 , and a first aspiration connector  918  which extends through the front wall  908  to the inside surface  917 . The rear wall  910  is provided with a second bore  920 , preferably threaded, into which the threaded connector  906  is secured, and a sample catch connector  926  which removably couples the sample catch assembly  900  to a distal portion of the shaft  30 . The rear wall is also provided with an inside surface  921 , a second aspiration connector  922 , and a proximal aspiration conduit  924  extending from the inside surface  921  to the second aspiration connector  922 . The tray holder  902  is also preferable provided with irrigation connectors  914 ,  915  which couple the first irrigation coupling tube  24  to the second irrigation coupling tube  25 . 
     The tray  904 , preferably polygonally shaped, includes an axial bore  927  and a plurality of chambers or cups  928   a - h  (indexed  1  through  8 , respectively, in  FIG. 18 ). Referring to  FIGS. 16 and 18 , each cup  928   a - h  has a filter or screen  930   a - h  and tapers to an outlet  932   a - h  ( 932   a ,  932   e  shown in  FIG. 16 ) proximal of the screen. The screen preferably has frustoconical perforations. The tray  904  is rotatable within the tray holder  902  such that each of the cups  928   a - h  is positionable between the first aspiration connector  918  and the proximal aspiration conduit  924  for receiving a tissue sample. The cups  928   a - h  are maintained in position by providing indentations  934   a - h  in the tray  904  which receives a protruberance  935  on the inside surface  921  of the rear wall  910  (see  FIGS. 15 and 17 ); i.e., a cup (for example,  928   a ) is held is position until sufficient force is provided to the tray  904  to rotate the tray and thereby position the next cup (for example,  928   b ) 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 indentations  934   a - h  and the protruberance  935 , a ratchet mechanism (not shown) can be provided to prevent rotation of a tray opposite to a predetermined direction. Preferably a stop  936  is also provided on the tray  904  to 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 indicia  938  to 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 tray  904  is rotated such that the next cup is positioned between the first aspiration connector  918  and the proximal aspiration conduit  924 . 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 connector  906  is 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 to  FIGS. 19 and 20 , a third embodiment of a multiple sample biopsy forceps instrument  210  is shown. The instrument includes a proximal actuation handle  212 , a flexible multi-lumen tubular member  214 , a pull wire  220 , and a distal assembly  222 . Several coupling tubes are preferably provided to couple the proximal actuation handle  212  to the tubular member  214  and to irrigation and aspiration means. In particular, a Y-shaped control coupling tube  223 , first and second irrigation coupling tubes  224 ,  225 , and first and second aspiration coupling tubes  226 ,  227  are provided. 
     The proximal actuation handle  212  is substantially similar to the first embodiment (with like parts having numbers incremented by 200). Referring to  FIGS. 20 ,  21  and  22 , the tubular member  214  is preferably a multi-lumen multi-layer extrusion, and preferably includes a first metal braid  276  beneath the outermost layer to add desired stiffness to the tubular member. If desired, a second metal braid  277  may be additionally provided around the aspiration conduit  274  to stiffen and support the aspiration conduit  274 . The tubular member  214  has a proximal end  266 , a distal end  268 , two control conduits  270 ,  271 , an irrigation conduit  272 , and an aspiration conduit  274 , each of the conduits  270 ,  271 ,  272 ,  274  extending through the tubular member to the distal assembly  222 . The aspiration conduit  274  has a substantially circular cross section. The irrigation conduit  272  has a generally kidney-shaped cross section and is separated from the aspiration conduit  274  by a membrane  275 . The control conduits  270 ,  271  are preferably situated one on either end of the membrane  275 . 
     Referring to  FIGS. 22 through 25 , the distal assembly  222  according to the third embodiment of the invention includes a stationary jaw  281  coupled, preferably by adhesion bonding, to the distal end  268  of the tubular member. The stationary jaw  281 , preferably made of plastic, includes a jaw cup  288 , an integral central clevis  293  and integral proximal ramps  295 ,  296 . The jaw cup  288  is located over the aspiration conduit  274  and preferably has a blunt cutting surface or lip  292 . The central clevis  293  and proximal ramps  295 ,  296  extend from the stationary jaw  281  and abut and partially cover the irrigation conduit. A movable jaw  290 , preferably made of metal, is provided with a sharp cutting edge  298 , defines two jaw holes  302 ,  304  for receiving a pull wire  220 , and is provided with two bosses  312 ,  314  for mounting the jaw. The bosses  312 ,  314  loosely engage the central clevis  293  and a pivot pin  294  extends through the bosses and the central clevis. The ramps  295 ,  296  of the stationary jaw  281  guide the movable jaw  290  when opening and closing and assist to form a substantially fluidtight passage between the movable jaw  290  and the stationary jaw cup  288  when the jaws are in a closed position. A central portion of the pull wire  220  which is perpendicular to the longitudinal axis of the instrument extends through the jaw holes  302 ,  304  and the ends of the pull wire extend into the control conduits  270 ,  271 . Turning back to  FIG. 20 , the Y-shaped coupling tube  223  facilitates alignment of the ends of the pull wire  220  for coupling the pull wire to the proximal actuation handle. The pull wire  220  may be coated, e.g., in a plastic, to inhibit the pull wire from cutting into the tubular member. 
     Referring to  FIGS. 23 and 25 , the distal end  268  of the tubular member is inserted through the lumen of an endoscope to a biopsy site. The jaws  288 ,  290  are moved into a closed position cutting off a tissue sample and further providing a substantially fluidtight coupling between the irrigation and aspiration conduits  272 ,  274 . While it appears from the illustrations of  FIGS. 23 and 25  that the irrigation conduit  272  is obstructed at the distal end by clevis  293 , it will be appreciated that the irrigation conduit  272  is substantially wider than the clevis and that fluid may flow around the clevis to the aspiration conduit  274 . 
     Turning now to  FIGS. 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 member  414  has a proximal end  466 , a distal end  468 , an irrigation conduit  472 , and an aspiration conduit  474 . The aspiration conduit  474  has a substantially circular cross section, while the irrigation conduit  472  has a generally crescent-shaped cross section. A control coupling tube  423  is coupled to the second irrigation coupling tube  425 . Two pull wires  420 ,  421  extend through the control coupling tube  423 , pass through a substantially fluidtight valve (not shown) coupling the control coupling tube  423  and the second irrigation coupling tube  425 , enter into the second irrigation coupling tube  425 , and extend through the irrigation conduit  472  to the distal end  468  of the tubular member. An aspiration coupling tube  427  is coupled to the aspiration conduit  474 . 
     Referring to  FIG. 28 , the distal assembly  422  of the fourth embodiment of the invention includes a stationary jaw  481  bonded to the distal end  468  of the tubular member, and a movable jaw  490  coupled thereto. The stationary jaw  481  includes a jaw cup  488 , an integral central clevis  493 , and ramps  495 ,  496 . The jaw cup abuts the distal end of the tubular member and is positioned over the aspiration conduit  474  and preferably has a blunt cutting surface or lip  492 . The central clevis  493  and ramps  495 ,  496  extend from the stationary jaw  481  and abut and partially cover the irrigation conduit  474 . A movable jaw  490 , preferably made of metal, is provided with a sharp cutting edge  498 , defines two jaw holes  402 ,  404  for receiving a pull wire  420 , and is provided with two bosses  512 ,  514  for mounting the jaw. The bosses  512 ,  514  loosely engage the central clevis  493  and a pivot pin  494  extends through the bosses and the central clevis. By partially covering the irrigation conduit, the ramps form entrances  499 ,  500  for the pull wires. The movable jaw  490  rides on the proximal ramps  495 ,  496  when moving from an open to a closed position. The pull wires  420 ,  421  are coupled to the jaw holes  502 ,  504  by a Z-bend  506 ,  507  and extend through the entrances  499 ,  500  into the irrigation conduit  472 , through a portion of the second irrigation coupling tube  425 , and further into a control coupling tube  423  coupled thereto. The entrances  499 ,  500  are 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 conduit  474  to the distal assembly. 
     Turning to  FIG. 29 , a fifth embodiment of the invention, substantially similar to the fourth embodiment (with like parts having numbers incremented by 200) is shown. The tubular member  614  is preferably a multi-lumen extrusion co-extruded with support wires  676 ,  677 ,  678 . The tubular member  614  has two irrigation conduits  672 ,  673 , and an aspiration conduit  674 . The aspiration conduit  674  has a substantially circular cross section, and the irrigation conduits  672 ,  673  have 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 wire  620 ,  621  extends through each irrigation conduit  672 ,  673 . By way of example, the preferred diameter for the tubular member  614  is approximately 2.8-3.3 mm, the preferred diameter for the aspiration conduit  674  is approximately 1.5 mm, and the preferred diameter for each of the support wires  676 ,  677 ,  678  is 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 to  FIG. 30 , it will be further appreciated that the three support wires may be replaced with a single larger high tensile support wire  676   a  or multiband cable through the tubular member  614   a . The support wire is preferably located substantially between the two irrigation conduits and the aspiration conduit. The single support wire  676   a  provides necessary support to the aspiration conduit  674   a  and 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.