Abstract:
A biopsy forceps has a handle and a pair of tissue cutting jaws that are separated by an elongate sheath. The tissue cutting jaws may be opened and closed to obtain a tissue sample. The tissue cutting jaws are removable from the distal end of the forceps so that a physician can use a different pair of tissue cutting jaws for each sample obtained. Tissue cutting jaws are distributed in trays for easy access by a physician.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to medical devices in general, and to biopsy forceps in particular.  
         BACKGROUND OF THE INVENTION  
         [0002]    A common medical device used with endoscopic procedures is a biopsy forceps. Such a device is an elongate cutter having a handle and a pair of tissue cutting jaws that are separated by a catheter or sheath. The tissue cutting jaws are operated by a cable or other mechanism that extends through the sheath into the handle. A physician inserts the forceps into a working channel of an endoscope and activates the jaws to obtain a tissue sample for analysis by a pathologist.  
           [0003]    In the past, if a physician wanted to biopsy more than one area of tissue, the physician would insert the device into the endoscope, obtain a biopsy sample and retract the device from the endoscope in order to place the tissue sample in an appropriate container. Alternatively, some biopsy forceps are multiple bite devices that can hold more than one tissue sample. The problem with each type of forceps design is that cross-contamination may occur between different tissue samples thereby providing the physician with an inaccurate assessment of the diseased state of the patient. While it is possible that the physician could use separate biopsy forceps for each sample, such a solution would require either many disposable devices to be used or could generate many devices that must be sterilized.  
           [0004]    Therefore, there is a need for a biopsy forceps that can obtain multiple tissue samples with less likelihood of cross-contamination and that does not require different devices to be used for each tissue sample.  
         SUMMARY OF THE INVENTION  
         [0005]    To solve these and other problems, the present invention is a biopsy forceps having removable cutting jaws. The biopsy device has a handle and a pair of cutting jaws separated by a catheter or sheath. A physician manipulates the handle to actuate the cutting jaws to retrieve a tissue sample. The cutting jaws can be selectively removed after each tissue sample is obtained and a new pair of jaws attached in order to obtain another tissue sample. Sets of cutting jaws can be distributed in a tray or other carrying device that allows the physician to easily attach a new pair of cutting jaws after each tissue sample is obtained. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0006]    The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:  
         [0007]    [0007]FIG. 1 illustrates a biopsy forceps in accordance with one embodiment of the present invention;  
         [0008]    [0008]FIG. 2 illustrates a tray of removable tissue cutting jaws in accordance with an aspect of the present invention;  
         [0009]    [0009]FIG. 3 illustrates one embodiment of a mechanism for removably securing a pair of tissue cutting jaws to the distal end of the biopsy forceps;  
         [0010]    [0010]FIG. 4 illustrates yet another embodiment of a mechanism for removably securing a pair of tissue cutting jaws to the distal end of a biopsy forceps; and  
         [0011]    [0011]FIG. 5 illustrates yet another embodiment of a mechanism for removably securing a pair of tissue cutting jaws to the distal end of a biopsy forceps. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0012]    As shown in FIG. 1, a biopsy forceps  10  in accordance with one embodiment of the present invention includes a catheter or sheath  12  having a distal end  14  and a proximal end  16 . At the distal end  14  of the sheath  12  is a pair of tissue cutting jaws  18 . The tissue cutting jaws  18  are removably secured to the biopsy forceps such that the jaws  18  can be exchanged for another pair of jaws after a tissue sample is obtained. A handle  20  at the proximal end of the sheath includes a stationary portion  22  having a thumb ring  23  and a slide  24  that moves with respect to the stationary portion  22  of the handle. The physician moves the slide  24  to open and close the tissue cutting jaws  18  and obtain a tissue sample.  
         [0013]    After a tissue sample has been retrieved, the physician can disengage the tissue cutting jaws  18  from the distal end  14  of the biopsy forceps  10  and a new pair of cutting jaws can be secured thereto in order to obtain another tissue sample.  
         [0014]    [0014]FIG. 2 shows a number of removable tissue cutting jaws  18   a ,  18   b ,  18   c  . . .  18   o  within a tray  30 . The physician can obtain a tissue sample with each pair of tissue cutting jaws and deposit the jaws with the tissue sample attached back into the tray  30  so that the tray can be forwarded to a pathologist or other analysis center for review and/or diagnosis. Once all the desired tissue samples have been obtained, the biopsy forceps  10  can be either disposed of, or depending upon the materials used to manufacture the biopsy forceps, the handle and sheath portion of the forceps can be sterilized for use with another patient. As will be appreciated, it is not necessary that the tissue samples remain in the tissue cutting jaws after they are obtained. Such samples could be placed in conventional specimen jars.  
         [0015]    [0015]FIG. 3 illustrates a mechanism for removably securing a pair of tissue cutting jaws to the distal end of a biopsy forceps in accordance with one embodiment of the present invention. In this embodiment, the sheath  12  includes an inner elongate member  40  and an outer sleeve  42  that slides over the inner elongate member  40 . The distal end of the inner elongate member  40  has a notch  44  that cooperates with a notch  46  at the proximal end of a pair of tissue cutting jaws  18 . In this embodiment, the interlocking notches join the cutting jaws  18  to the distal end of the inner elongate member  40 . The outer sleeve  42  slides over the interlocking notches in order to maintain their position within the outer sleeve  42 . Thus, while the outer sleeve  42  is positioned over the joint between the interlocking notches, the cutting jaws  18  are secured to the distal end of the biopsy forceps. In one embodiment of the invention, the tissue cutting jaws  18  are biased radially outward such that upon movement of the outer sleeve  42  in the distal direction, the jaws are urged into a closed position. Upon retraction of the outer sleeve  42 , the jaws are allowed to open to retrieve a tissue sample. Upon further retraction of the outer sleeve  42 , the joint between the interlocking notches is uncovered and the distal end of the inner elongate member  40  can be removed from the proximal end of the tissue cutting jaws  18 .  
         [0016]    In the embodiment shown in FIG. 3, the inner elongate member  40  is preferably connected to the stationary handle  22  while the outer sleeve  42  is preferably connected to the movable slide  24  such that the physician can control the opening and closing of the jaws as well as the removal of the cutting jaws  18  with one hand. A button  26  (shown in FIG. 1) may be provided to limit the movement of the slide  24 . The position of the button  26  allows the outer sleeve  42  to be moved past the joint between the interlocking notches in order to exchange the tissue cutting jaws  18 .  
         [0017]    [0017]FIG. 4 shows an alternative embodiment of a mechanism for releasably securing a pair of tissue cutting jaws  18  to the distal end of the biopsy forceps. In this embodiment, the biopsy forceps includes an inner elongate member  60  and an outer sleeve  62 . Within the inner elongate member  60  is a spring loaded actuating cable  64  having a cylinder  66  disposed at its distal end. The cylinder  66  includes one or more slots  68  in which radially extending pins  70  ride. The pins  70  extend radially outwards from the cylinder such that they extend through the side of the inner elongate member  60  and into corresponding holes  72  on a pair of tissue cutting jaws in order to secure the jaws to the forceps. Movement of the cylinder  66  by the cable  64  causes the pins  70  to move radially inwards and outwards. With the pins  70  in the radially outward position, they engage corresponding holes  72  on the proximal end of the tissue cutting jaws  18 . When the cable  64  is moved in the proximal direction, the ends of the pins move in the slots  68  to pull the pins  70  radially inwards, thereby releasing the tissue cutting jaws  18  from the forceps so that a new pair of cutting jaws can be installed.  
         [0018]    [0018]FIG. 5 illustrates yet another mechanism for removably securing a pair of tissue cutting jaws  18  to the distal end of the biopsy forceps. In this embodiment, the biopsy forceps has an inner elongate member  80  and an outer sleeve  82 . At the distal end of the inner elongate member  80  are one or more spring loaded balls  84  that engage a race or other indentation on the inner surface of the proximal end of the tissue cutting jaws  18 . By compression of a ball  18  and its subsequent release within the race or indentation, the tissue cutting jaws  18  are held in a friction fit at the distal end of the biopsy forceps. The outer sleeve  82  is movable over the jaws in order to open and close them as with the embodiments shown in FIGS. 3 and 4. The tissue cutting jaws  18  can simply be pulled off a distal end of the inner elongate member  80  and a new pair of jaws installed by forcing the distal end of the inner elongate member  80  into the proximal end of another set of jaws.  
         [0019]    While the preferred embodiment of the invention has been illustrated and described, it will be appreciated that various changes can be made therein without departing from the scope of the invention. Therefore, it is intended that the scope of the invention is to be determined from the following claims and equivalents thereof.