Abstract:
A method and apparatus for removing polyps from an inner lining of an internal cavity uses a polyp-severing head extending from one end of a sheath. The polyp-severing head comprises a conductive hook or conductive forceps for engaging the polyp and for discharging electrical energy into the engaged polyp to sever the polyp from the inner lining of the internal cavity. In exemplary applications, a physician manipulates the polyp-severing head around the polyp and engages the polyp near the inner lining surface. The physician then discharges electrical energy into the polyp via the polyp-severing head. The electrical energy transferred from the polyp-severing head to the engaged portion of the polyp severs the polyp from the inner lining surface.

Description:
BACKGROUND OF THE INVENTION 
   The present invention generally relates to a method and apparatus for removing polyps from the inner lining of an internal cavity, and more particularly to a method and apparatus for engaging and removing polyps from the large intestine or colon. 
   Polyps are fleshy growths that form on an inner lining of an internal cavity, such as the stomach, uterus, urinary tract, esophagus, colon, etc. Colon polyps are the most common and the most dangerous. This is largely due to the fact that approximately 75% of all colon polyps are cancerous polyps, also known as adenomas. Further, as colon polyps grow larger, the chance of colon cancer increases. Because colon cancer is the second leading cause of cancer related death in the United States, most medical professionals recommend the removal of any colon polyp. 
   As late as the mid 1960&#39;s, removing colon polyps required entering the colon by cutting through the abdomen wall. Such major surgery had numerous possible complications and a long recovery time. Colonoscopic polypectomy, an endoscopic procedure for examining and removing polyps from the colon, was introduced in the late 1960&#39;s. This procedure uses endoscopic technology to capture and remove polyps from the colon or large intestine. Typically a physician inserts an endoscopic snare, such as a sharp edged or conductive loop, into the colon, and fits the loop over the head of the polyp. The physician then cuts or burns through the base of the polyp with the loop. The physician may capture the severed polyp using suction, baskets, nets, etc. While the prior techniques have proven effective, conventional snares cannot always fit over relatively large polyps, making it difficult, if not impossible, to use conventional endoscopic procedures to remove such relatively large polyps. 
   SUMMARY OF THE INVENTION 
   The present invention is directed to a method and apparatus for removing polyps from an inner lining of an internal cavity. In an exemplary embodiment, the apparatus includes a polyp-severing head extending from one end of a sheath. The polyp-severing head includes a conductive hook for engaging the polyp. The conductive hook discharges electrical energy into an engaged polyp to sever the polyp from the inner lining of the internal cavity. 
   In exemplary applications, a physician manipulates the conductive hook around the polyp and engages the polyp. The physician then discharges electrical energy into the polyp via the conductive hook. The electrical energy transferred from the conductive hook to the engaged portion of the polyp severs the polyp from the inner lining surface. 
   In another exemplary embodiment, the polyp-severing head includes forceps for engaging the polyp. The forceps include conductive opposing inner edges that discharge electrical energy into the engaged polyp to sever the polyp from the inner lining of the cavity. In this embodiment, the physician opens the forceps near the polyp, manipulates the open forceps around to polyp, and closes the forceps to engage the polyp. The physician then discharges electrical energy into the forceps to sever the polyp from the inner lining surface. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of the polyp surgical device of the present invention. 
       FIG. 2  illustrates the polyp severing head of the polyp surgical device of  FIG. 1 . 
       FIG. 3A  illustrates the polyp-severing head of  FIG. 2  withdrawing into a collapsed configuration. 
       FIG. 3B  illustrates the polyp-severing head of  FIG. 2  withdrawing into an alternate collapsed configuration. 
       FIG. 4  illustrates the handle of the polyp surgical device of  FIG. 1 . 
       FIG. 5  is a schematic view showing the connector and controls for the polyp surgical device. 
       FIG. 6A  illustrates the polyp severing head of the polyp surgical device disposed around a polyp. 
       FIG. 6B  shows the polyp severing head of  FIG. 6A  withdrawn/retracted around the polyp. 
       FIG. 6C  illustrates the severed polyp and the collapsed polyp-severing head. 
       FIG. 6D  illustrates the polyp surgical device removing the severed polyp from the internal cavity of the patient. 
       FIG. 7A  illustrates another exemplary polyp-severing head in a closed position. 
       FIG. 7B  illustrates the polyp-severing head of  FIG. 7A  in an open position. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  illustrates a polyp surgical device  100  for removing polyps from an internal cavity according to the present invention. Polyp surgical device  100  comprises polyp-severing head  110 , lead cable  120 , handle  130 , connector cable  140 , and connector  150 . A lead wire  122  disposed in an outer sheath  124  of lead cable  120  (see  FIG. 5 ) mechanically connects polyp-severing head  110  to handle  130 . Manipulating handle  130  causes relative movement between polyp-severing head  110  and outer sheath  124  of lead cable  120 , as described further below. In addition, lead wire  122  electrically connects polyp-severing head to a connector wire  142  disposed in an outer sheath  144  of connector cable  140  (see  FIG. 5 ) at handle  130 . Connector wire  142  also electrically connects to connector  150 , as described further below. As a result, connector wire  142  and lead wire  122  electrically connect polyp-severing head  110  to connector  150 . 
     FIG. 2  illustrates an embodiment for polyp-severing head  110  according to the present invention. Polyp-severing head  110  comprises a continuation of lead wire  122  extending outwardly from outer sheath  124  and shaped generally as a hook  112 . At a tip  114  of hook  112 , the wire loops around, follows the general contour of hook  112 , and re-enters outer sheath  124 . The hook  112  illustrated in  FIG. 2  provides a complete electrical path from connector  150  to hook  112  as described further below. In addition, hook  112  provides an open space  115  between tip  114  and the body of the hook  112 . It should be appreciated that the general shape of the hook  112  could vary, and that the manner of directing electrical energy through the hook  112  may also vary. Therefore, the present invention is not limited to the conductive hook  112  described above. 
   To ensure that conductive wire  122  does not short out inside outer sheath  124  of lead cable  120 , lead cable  120  may include an insulator (not shown) for isolating the wires  122  encased in outer sheath  124 . Alternately, the wires  122  disposed in outer sheath  124  may be encased in an insulative sleeve (not shown). Conductive hook  112  may also include an insulative backing, such as a flexible plastic backing (not shown), to prevent electrical shorts along hook  112 . 
   In a preferred embodiment, conductive hook  112  is capable of moving with respect to the outer sheath  124 . In such embodiments, moving control  132  on handle  130  back and forth extends and withdraws conductive hook  112  with respect to outer sheath  124 . In a first embodiment, moving control  132  withdraws conductive hook  112  partially or wholly into outer sheath  124 , as shown in  FIG. 3A . Alternatively, moving control  132  withdraws conductive hook  112  into outer sheath  124  until an external opening  126  in lead cable  120  secures tip  114  of conductive hook  112 , as shown in  FIG. 3B . It will be appreciated by those skilled in the art that the relative movement of conductive hook  112  is not limited to the embodiments described above. 
     FIG. 4  illustrates an exemplary handle  130  applicable to the present invention. While the present invention utilizes the handle  130  shown in  FIG. 4 , those skilled in the art will recognize that other known handles are equally applicable to the present invention. Handle  130  provides a movable control, such as a thumb control  132 , for mechanically controlling conductive hook  112 . In one embodiment, thumb control  132  is operatively connected to conductive hook  112  via conductive wire  122 . As thumb control  132  is moved back and forth, conductive hook  112  extends and retracts from and into outer sheath  124 . 
   As shown in  FIG. 4 , one end of connector cable  140  extends from handle  130 . Attaching a connector  150  disposed on the opposite end of connector cable  140  to an electrical supply  156  electrically connects conductive hook  112  to electrical supply  156 , as shown in  FIG. 5 . Details regarding electrical supply  156  are not addressed in the present application because such electrical supplies are well known in the art and are commercially available. Connector  150  may be any connector known in the art that includes at least two pins. In a preferred embodiment, connector  150  comprises a 2-contact coaxial connector (see  FIG. 1 ) with an outer ground contact  154  connected to one end of connector wire  142  and a center power pin  152  connected to another end of connector wire  142 . Activation of a properly connected electrical supply  156  causes polyp-severing head  110  to discharge electrical energy. 
     FIGS. 6A-6D  illustrate a surgical procedure that uses the polyp surgical device  100  of  FIGS. 1-5  to remove a polyp  164  attached to surface  162  of an internal cavity, such as a colon  160 . While the following describes the removal of colon polyps, those skilled in the art will appreciate that the present invention may remove polyps from any internal cavity, such as the stomach, uterus, urinary tract, esophagus, or the like. 
   A physician inserts polyp surgical device  100  into colon  160 , via an external opening of a patient, until conductive hook  112  is proximate a polyp  164 . The physician may use a wide variety of techniques to locate polyp  164 . Such techniques are well known in the art, and therefore, are not discussed further herein. Once appropriately positioned, the physician manipulates conductive hook  112  around polyp  164  such that polyp  164  passes through the opening  115 , as illustrated in  FIG. 6A . The physician then engages polyp  164  ( FIG. 6B ) by manipulating control  132  of handle  130  to withdraw conductive hook  112  about polyp  164  to engage polyp  164 . The physician then activates electrical supply  156  while continuing to withdraw conductive hook  112  about polyp  164  to simultaneously strangle and sever polyp  164  from surface  162  while cauterizing the resulting wound  167  ( FIG. 6C ). 
   Once severed from surface  162 , the physician may remove severed polyp  164  from the colon by various conventional means. For example, the physician may capture the severed polyp  164  with the conductive hook  112  and pull the severed polyp  164  from the colon by withdrawing the polyp surgical device  100  from the colon. Alternatively, the outer sheath  124  may be operatively connected to a vacuum source (not shown). The lead cable  120  may then be utilized to create a vacuum in the outer sheath  124 . After completely withdrawing conductive hook  112  into lead cable  120  ( FIG. 6C ), the physician may secure the severed polyp  164  to the tip of lead cable  120  by activating the vacuum source to apply suction to the severed polyp  164 . While severed polyp  164  is secured to the tip of lead cable  120 , the physician removes the polyp surgical device  100  and the severed polyp  165  from colon  160  ( FIG. 6D ). 
   The polyp surgical device  100  of the present invention is not limited to the conductive hook  112  described above. For example, as illustrated in  FIGS. 7A and 7B , polyp-severing head  110  of the present invention may comprise a pair of conductive forceps  170 . Conductive forceps  170  comprise a left prong  172  and a right prong  174  connected at one end of lead cable  120 . For example, a pivot pin, a hinge, a spring-loaded joint, etc., may connect prongs  172 ,  174  at the tip of lead cable  120 . Conductive forceps  170  may be opened or closed by manipulating control  132  of handle  130 . 
   Left prong  172  and right prong  174  electrically connect to connector  150  via lead cable  120  and handle  130  according to any means know in the art. For example, in a first embodiment, a power wire (not shown) may connect left prong  172  to center pin  152  of connector  150 , while a ground wire (not shown) may connect right prong  174  to outer contact  154  of connector  150 . As a result, conductive forceps  170  will only dissipate electrical energy when the tips  176  of prongs  172 ,  174  complete the electrical circuit. Alternatively, in a second embodiment, each prong  172 ,  174  of conductive forceps  170  may comprise one or more embedded wires (not shown) that provide a complete electrical circuit from each prong  172 ,  174  to connector  150 . As a result, each prong  172 ,  174  of the conductive forceps  170  of the second embodiment may dissipate electrical energy even when the tips  176  do not come into contact. 
   In an exemplary procedure, a physician inserts the conductive forceps  170  of  FIG. 7A  into the colon of a patient while conductive forceps  170  are in a closed position ( FIG. 7A ). Once appropriately positioned proximate polyp  164 , the physician opens conductive forceps  170  and positions polyp  164  between the separated prongs  172 ,  174 . The physician then engages polyp  164  by manipulating control  132  of handle  130  to grasp polyp  164  between the prongs  172 ,  174  of conductive forceps  170 . Once the conductive forceps  170  have engaged polyp  164 , the physician activates electrical supply  156  while closing the conductive forceps  170  to simultaneously strangle and sever polyp  164  from surface  162  and to cauterize the resulting wound  167 . Once severed, the physician may remove polyp  164  from the colon by any means well known in the art. 
   In summary, the above described methods and apparatus may easily engage and remove polyps, even larger polyps that do not fit within conventional snare techniques. Therefore, the polyp-removing methods and devices of the present invention are applicable to a larger percentage of polyps than conventional techniques, providing a physician with additional less-invasive treatment options for relatively large polyps. 
   The foregoing description and drawings describe and illustrate the present invention in detail. However, the foregoing only describes some embodiments of a polyp-severing device. Accordingly, the present invention may be carried out in specific ways other than those set forth herein without departing from the essential characteristics of the invention. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claims are intended to be embraced therein.