Abstract:
An endoscopic tissue resection device and related method is used in conjunction with a flexible or rigid endoscope. Tissue is resected by shaving thin layers of tissue for diagnostic and therapeutic purposes.

Description:
CROSS-REFERENCE TO RELATED APPLICATION  
       [0001]     This application claims the benefit of U.S. Provisional Patent Application No. 60/611,260 filed Sep. 17, 2004. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     This invention relates to endoscopic medical procedures and more particularly to endoscopic mucosal resection procedures. This invention also relates to an endoscopic instrument or assembly utilizable in performing an endoscopic mucosal resection procedure.  
         [0003]     The precancerous nature of high-grade dysplasia and the difficulty in detection of invasive carcinoma by endoscopy make esophagectomy and ablative therapy important considerations to treating those patients with this serious condition. The gold standard treatment for early esophageal cancer and high grade dysplasia is esophagectomy, the surgical removal of the diseased segment of the esophagus. This is an effective but drastic treatment and presents significant complications and lifestyle problems for the patient. Many patients are poor surgical candidates for this difficult surgery.  
         [0004]     Endoscopic mucosal resection (EMR), the removal of mucosal tissue by use of a snare, is a therapeutic alternative and has become a standard treatment for patients with Barrett&#39;s Esophagus. This technique preserves the patient&#39;s esophagus while resecting the mucosa that is affected by this disease. A second method is tissue ablation with heat therapy. EMR is superior to tissue destruction because it permits pathologic evaluation of the resected specimen. Current endoscopic mucosal resection techniques for the treatment of esophageal cancer include strip biopsy, double snare polypectomy, with the combined use of saline and epinephrine injection. EMR may be curative if the primary tumor or dysplastic tissue is removed completely.  
         [0005]     Another area where EMR may be used is for removal of large sessile polyps in the GI tract, primarily the colon. The malignant transformation potential of colorectal adenomatous polyps is well documented. Colonoscopic polypectomy is widely practiced in order to prevent the development of colon cancer. Sessile polyps are premalignant lesions that lay flatly on the mucosal surface of the colon wall. These lesions, in contrast to pedunculated polyps, are devoid of a stalk, and are broad based. The colon wall is composed of several layers: the mucosa (the surface layer), the submucosa, the muscularis (muscle layer), and the serosa (connective tissue layer). The thickness of the entire wall is 5 mm. When a cautery snare is used to remove a larger sessile lesion, it may catch part of the muscularis layer Cutting through the muscle layer causes a colonic perforation.  
         [0006]     Devices currently used for EMR procedures are polypectomy snares and a variety of devices to assist in the use of these snares. For resection of dysplastic tissue in the esophagus the technique involves using 2 snares, one to hold up the targeted tissue and the other to sever that tissue. The use of saline solutions for injection beneath the target tissue is a common practice for the purpose of raising the tissue and creating a buffer layer. This process is called saline assisted polypectomy (SAP).  
         [0007]     In the case of sessile colonic polyps, SAP is standard medical practice. The raised polyp is then severed with a polypectomy snare, often in several segments (segmental resection) depending on the size and location of the polyp.  
         [0008]     The depth of the cut that occurs using the snare cautery device to remove dysplastic mucosal tissue is critical. As discussed above, if the cut is too deep, injuring the muscularis layer, a perforation may occur. Conversely, a cut too shallow may not remove enough of the affected tissue and therefore may require additional procedures, or worse, result in the development of metastatic cancer. Similar complications may occur during the removal of sessile colonic polyps. The colonic wall is approximately the same thickness as the esophageal wall, namely 5 mm. A perforation as a result of cutting into the muscularis layer will cause a colonic perforation, while a lesion that is not completely removed, either due to insufficient depth or breath, will result in recurrence of the dysplastic tissue. Repeated resections after a certain interval are recommended if the margin of resection achieved during the procedure is too close to the tumor. More than 2 mm of cancer clearance is required. The complications resulting from EMR as performed with today&#39;s devices and methods include perforation, bleeding, and strictures that occur from scar formation resulting from EMR procedures.  
         [0009]     Ablation techniques rely on chemicals which, when combined with heat or freezing, destroy dysplastic tissue. Adverse reactions include destruction of the healthy tissue surrounding the lesion, allergic reactions to the chemicals and sensitivity to sun-light. Furthermore, all ablative techniques destroy the tissue and prevent adequate pathologic examination of the specimen.  
       OBJECTS OF THE INVENTION  
       [0010]     An object of the present invention is to provide a method for resecting dysplastic tissue masses disposed along internal organ walls.  
         [0011]     It is a more particular object of the present invention to provide an instrument that will enable accurate removal of tissue that lies flatly on the mucosal wall of the gastrointestinal tract.  
         [0012]     It is another more particular object of the present invention to provide such a method and/or instrument that reduces the likelihood of organ perforation.  
         [0013]     It is another object of the present invention to provide such a method that is minimally invasive.  
         [0014]     It is even a more particular object of the present invention to provide an instrument and accompanying method that enables control of the depth and breadth of resection.  
         [0015]     A further object of the present invention is to provide such a method that is carried out endoscopically.  
         [0016]     It is a particular object of the present invention to provide an instrument that may be used in conjunction with a flexible endoscope, whereby the instrument&#39;s end effector is larger than the working channel of the endoscope.  
         [0017]     These and other objects of the invention will be apparent from the drawings and descriptions herein. Although every object of the invention is believed to be achieved by at least one embodiment of the invention, there is not necessarily any single embodiment that achieves all of the objects of the invention.  
       SUMMARY OF THE INVENTION  
       [0018]     A medical device comprises, in accordance with the present invention, at least one elongate instrument shaft insertable through a working channel of an endoscope, a holder member provided at a distal end of the instrument shaft, and a cutting wire element connected to the holder member. The wire element extends between spaced points of the holder member in a use configuration of the holder member and the wire element.  
         [0019]     In several embodiments of the invention, the cutting wire is made of electrically conductive material operatively connectable to a source of electrical current, thereby enabling a cauterization of organic tissues during a cutting operation.  
         [0020]     Typically, the holder member has a Y- or V-shaped configuration in the use configuration, the holder member having a pair of arms extending at an angle relative to one another. The wire element extends in a straight line from one arm of the holder member to another arm thereof. The arms of the holder member may be pivotably connected to one another and disposed in an insertion configuration inside the working channel of the endoscope. After insertion of distal end portion of the endoscope into a patient, the operative tip of the instrument is ejected from the endoscope working channel. The operative tip is then reconfigured from the insertion configuration to the use configuration.  
         [0021]     The insertion configuration of the holder member may be a collapsed configuration, in which case the change in conformation of the operative tip involves an opening of the holder member, a spreading of two pivotably interconnected arms, and the stretching of the wire element from a loose or flaccid loop to a straight and taut line.  
         [0022]     Alternatively, the insertion configuration of the holder member may be a straight line configuration having a pair of joints, bend points, or articulations. Upon the ejection of the holder member from the working channel of the endoscope (or from a tubular introducer sheath itself slidably inserted inside the working channel), the holder member is folded at the joints, bend points, or articulations to form a triangular or V-shaped use configuration. This conformation change may be effectuated by pulling on the wire element, which is fixedly connected to the tip of the holder element, and on a second wire which is connected to a distal-most joint, bend point, or articulation of the holder member.  
         [0023]     In either of the above-described embodiments of the holder member, the arms are pivotably connected to one another. In the one embodiment, the arms are each connected at a proximal end to the instrument shaft. The arms may be spring biased towards an opened configuration. In the other embodiment, the arms are connected in series to one another and to the instrument shaft, the one arm being connected at one end to the instrument shaft and at an opposite end to the other arm.  
         [0024]     Where the holder member comprises a pair of jaws pivotably connected to one another and to the distal end of the instrument shaft, the wire element originates from a proximal end of the instrument shaft, extends along the instrument shaft and one of the arms, and forms a straight line from the one arm to the other arm in the use configuration.  
         [0025]     In yet another embodiment of the present invention, the arms of the holder member are rigid elements fixed to one another exemplarily in a Y- or V-shaped configuration. In that case, the holder member arms and the wire element are disposable in a plane oriented perpendicularly to the instrument shaft, at least during an insertion or deployment procedure. More particularly, the holder member and the wire element are disposable along a distal end face of an endoscope member and inserted into the patient while riding on the front or distal end face of the endoscope insertion member. The holder member may be removably connectable to the end of the instrument shaft. In that case, before initiation of the endoscopic procedure, and in preparation thereof, the instrument shaft is inserted into the working channel of the endoscope from the proximal end. The holder member is subsequently screwed onto or otherwise connected to the distal end of the instrument shaft as it protrudes from the distal end of the endoscope working channel. After formation of this connection, the instrument shaft is pulled in the proximal direction until the holder member and the wire element lay snugly against the leading or distal end face of the endoscope insertion member. The endoscope insertion member is inserted into the patient with the operative tip (holder member and cauterizing wire element) engaging or touching the distal end face of the endoscope. The wire element preferably takes a substantially semi-rigid arcuate form that fits around the periphery of the endoscope end face. The two arms of the holder member are positioned such that the visualization optics, air channel, lens, and biopsy channels of the endoscope are not obstructed. Similarly, the wire element&#39;s positioning around the periphery is also such as not to interfere with these essential elements of the endoscope&#39;s distal end.  
         [0026]     A medical method in accordance with the present invention utilizes a medical instrument including an elongate wire element coupled to a holder member. At least a portion of the instrument including the wire element and the holder member is introduced into a patient via an endoscope Thereafter the wire element is placed into engagement with a patient&#39;s organic tissue at a surgical site. The wire element is moved into and along the tissue to remove a thin layer or web of the tissue.  
         [0027]     Optionally, in certain preferred embodiments of the present invention, the wire element is made of electrically conductive material and is connectable to a source of electric current. During the motion of the wire element in such embodiments, electrical current is conducted into the wire element to facilitate a cutting and cauterizing of the tissue at the surgical site.  
         [0028]     The wire element may extend between two points on the holder member. The moving of the wire element into and along the tissue may then include pulling the holder member from outside the patient to draw the wire element towards a distal end face of the endoscope. More particularly, movement of the wire element may be effectuated by moving the instrument shaft and holder assembly relative to the endoscope or, alternatively, by holding the cutting wire and holder element stationary relative to the endoscope, and manipulating the endoscope to guide the cutting and cauterizing action.  
         [0029]     The holder member may include a pair of arms pivotably connected to one another. In that case, the method may further comprise opening the arms from a collapsed configuration to an opened use configuration upon an ejection of the holder member from a distal end of the working channel. The arms may be opened by pivoting the arms relative to one another.  
         [0030]     The holder member may include a pair of arms connected in series to one another and to the instrument shaft, one of the arms being connected at one end to the instrument shaft and at an opposite end to another of the arms. In that case, the method may further comprise bending or folding the arms relative to one another to form a use configuration upon an ejection of the holder member in a straightened configuration from a distal end of the working channel. The bending or folding of the arms may include a pivoting of the arms relative to one another.  
         [0031]     In another embodiment of the present invention, the method may comprise disposing the holder member and the wire element along a distal end face of an insertion member of the endoscope. The introducing of the wire element and the holder member into the patient may include inserting the insertion member into the patient with the wire element and the holder member disposed along the distal end face of the endoscope insertion member. In this embodiment of the invention, a shaft of the medical instrument may be inserted into the working channel of the endoscope and then the holder member attached to the instrument shaft. The disposing of the holder member and the wire element along the distal end face is performed subsequently to the attaching of the holder member to the instrument shaft. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0032]      FIG. 1  is a perspective view of a first embodiment of a cutting and cauterizing instrument as it emerges from the distal end of an endoscope, in accordance with the present invention.  
         [0033]      FIG. 2  is a perspective view of the cutting and cauterizing instrument of  FIG. 1 , upon a manipulation of push bars or wires by actuation of the handle mechanism.  
         [0034]      FIG. 3  is a perspective view of the cutting and cauterizing instrument of  FIGS. 1 and 2  in a fully open position ready for tissue resection.  
         [0035]      FIG. 4  is a perspective view of the cutting and cauterizing instrument of  FIGS. 1-3  slicing a section of tissue.  
         [0036]      FIG. 5  is a perspective view of a handle mechanism of the cutting and cauterizing instrument of  FIGS. 1-4 .  
         [0037]      FIG. 6  is a perspective view of an alternative embodiment of a cutting and cauterizing instrument pursuant to the present invention, showing an operative tip of the instrument in a collapsed configuration inside a tubular introducer or deployment member.  
         [0038]      FIG. 7  is a perspective view of the cutting and cauterizing instrument of  FIG. 6  wherein a push bar or wire is advanced distally and two holder rods or arms of the operative tip begin to spread apart into an open configuration.  
         [0039]      FIG. 8  is a perspective view of the cutting and cauterizing instrument of  FIGS. 6 and 7 , showing the operative tip in the fully open configuration ready for tissue resection.  
         [0040]      FIG. 9  is a perspective view of the cutting and cauterizing instrument of  FIGS. 6-8 , showing the instrument being used to slice a section of tissue along a wall of an internal organ.  
         [0041]      FIG. 10  is a perspective view of the handle mechanism for the embodiment of  FIG. 6 .  
         [0042]      FIG. 11  illustrates an alternative embodiment of a cutting and cauterizing instrument, in accordance with the present invention.  
         [0043]      FIG. 12  is a blown up view of an arch structure of the instrument or device of  FIG. 11 .  
         [0044]      FIG. 13  is a schematic perspective view of a distal working end of an alternative embodiment of the cutting and cauterizing instrument, in accordance with the present invention.  
         [0045]      FIG. 14  is a schematic longitudinal cross-sectional view of the device of  FIG. 13 .  
         [0046]      FIG. 15  is a schematic perspective view of a further alternative embodiment of a cutting and cauterizing instrument, in accordance with the present invention.  
         [0047]      FIG. 16  is a schematic perspective view of a scissor-type handle mechanism alternatively utilizable with the cutting and cauterizing instrument of  FIG. 15 .  
         [0048]      FIG. 17  is a schematic perspective view of a distal working end of the cutting and cauterizing instrument shown in  FIG. 15 , with jaws in an open configuration.  
         [0049]      FIG. 18  is a schematic side elevational view, partially in section, of the cutting and cauterizing instrument of  FIG. 15 , with jaws in a partially closed configuration.  
         [0050]      FIG. 19  is a schematic side elevational view, partially in section, of the cutting and cauterizing instrument of  FIG. 15 , with jaws in a completely closed configuration.  
         [0051]      FIG. 20  is a side elevational view, partly in section, of another alternative embodiment of a cutting and cauterizing instrument, with jaws in an open use configuration ready for cutting.  
         [0052]      FIG. 21  is a schematic perspective view of the cutting and cauterizing instrument of  FIG. 20 , with jaws in the open use configuration.  
         [0053]      FIG. 22  is a schematic cutaway or longitudinal cross-sectional view of the cutting and cauterizing instrument of  FIGS. 20 and 21 , in a closed, pre-deployment configuration.  
         [0054]      FIG. 23  is a schematic perspective view of the cutting and cauterizing instrument of  FIGS. 20-22 , in the closed, pre-deployment configuration.  
         [0055]      FIG. 24  is a perspective view of a jaw or arm element of a wire holder member utilizable as a modification of the cutting and cauterizing instrument of  FIGS. 20-24 .  
         [0056]      FIG. 25  is a longitudinal cross-sectional view of the jaw or arm element shown in  FIG. 24 .  
         [0057]      FIG. 26  is a front end elevational view of the jaw or arm element of  FIGS. 24 and 25 .  
         [0058]      FIG. 27  is a schematic elevational view of a further modification of the cutting and cauterizing instrument of  FIGS. 20-23 .  
         [0059]      FIG. 28  is a schematic side elevational view, on a reduced scale, of another embodiment of an endoscopic cutting and cauterizing instrument in accordance with the present invention, showing an operative tip in a folded use configuration.  
         [0060]      FIG. 29  is a schematic perspective view, on a larger scale, of a distal end portion of the endoscopic cutting and cauterizing instrument of  FIG. 28 , showing the distal end portion, including a wire element and a holder member, in a straightened insertion configuration.  
         [0061]      FIG. 30  is a schematic perspective view, on an even larger scale, of the distal end portion of the endoscopic cutting and cauterizing instrument of  FIGS. 28 and 29 , showing the distal end portion in a partially folded configuration.  
         [0062]      FIG. 31  is a schematic perspective view, on an enlarged scale, of the distal end portion of the endoscopic cutting and cauterizing instrument of  FIGS. 28-30 , showing the distal end portion in the completely folded, use configuration of  FIG. 28 .  
         [0063]      FIG. 32  is a schematic perspective view of the distal end portion of the endoscopic cutting and cauterizing instrument of  FIGS. 28-31 , showing a stage in the use of the instrument to plane or shave a layer of tissue from inside a tubular organ.  
         [0064]      FIG. 33  is a schematic perspective view of an endoscope assembly including another embodiment of a cutting and cauterizing instrument in accordance with the present invention.  
         [0065]      FIGS. 34A through 34D  are schematic perspective views of a distal end portion of the endoscope of  FIG. 33 , showing successive steps in forming an insertion configuration of the cutting and cauterizing instrument together with the endoscope.  
         [0066]      FIGS. 35A through 35C  are schematic perspective views of the distal end portion of the endoscope of  FIGS. 33 and 34 A- 34 D, showing successive steps in the use of the instrument assembly in an endoscopic resection procedure, in accordance with the present invention.  
         [0067]      FIGS. 36A and 36B  show successive steps in utilization of a modification of the cutting and cauterizing instrument assembly of FIGS.  33 ,  34 A- 34 D, and  35 A- 35 C.  
         [0068]      FIG. 37A  is a schematic side elevational view, partially in cross-section, of a modification of the cutting and cauterizing instrument assembly of  FIGS. 36A and 36B , showing a transverse or angled configuration of the assembly.  
         [0069]      FIG. 37B  is a schematic side elevational view of the cutting and cauterizing instrument assembly of  FIG. 37A , showing a straightened configuration of the assembly.  
         [0070]      FIG. 37C  is a schematic end elevational view of the cutting and cauterizing instrument assembly of  FIG. 37A , taken from the left side in  FIG. 37A .  
     
    
     DEFINITIONS  
       [0071]     The present invention is directed to a medical or surgical procedure for removing an undesirable tissue mass located along the surface of a lumen of an internal organ such as the esophagus or the colon. Typically, multiple passes are made along the tissue mass by a shaving device as described herein, to ablate a series of web- or sheet-shaped portions of the undesirable tissue mass in a controlled fashion.  
         [0072]     The following are definitions of some terms used in this disclosure.  
         [0073]     The term “wire element” is used herein to denote a thin elongate cutting member that functions to ablate or otherwise cut organic tissues of a patient in a shaving procedure. Such a cutting element is preferably but not necessarily made of an electrically conductive material, generally a metal or alloy. In that case cutting and cauterizing is effectuated in large part by hear generated owing to the conduction of electrical current. Alternatively, the wire may cause cutting by freezing, or by slicing through tissue such as a cheese cutter would slice through cheese, simply by virtue of the wire&#39;s sharpness. A wire element as disclosed herein may be flexible or substantially rigid or semi-rigid. A semi-rigid wire element has some flexibility but has an inherent spring bias that tends to returns the wire to a preselected configuration, such as a circular arc. The wire element may be connected at spaced points to a holder member.  
         [0074]     The term “holder member” is used herein to denote a support for a wire element. In some embodiments of the invention, an active portion of the wire element extends between two points of the holder member so as to be free to ablate and cauterize or otherwise resect abnormal tissue.  
       DETAILED DESCRIPTION OF THE INVENTION  
       [0075]      FIGS. 1-5  illustrate one embodiment of the invention that includes an electrocautery device capable of being passed through the working channel  12  of an endoscope  10 . Referring to  FIG. 1 , an elongated tube  14  might be positioned in the channel  12  to emerge from the distal end of endoscope  10 . The cutting device or assembly  16  is moved through the elongate tube  14  to emerge therefrom. The device  16  includes one or more push bars or wires  18  that are generally parallel to one another. The push bars or wires  18  are coupled to a corresponding pair of rigid or semi rigid electrically conductive rod elements or rods  20  and a crossbar element  22  that spans between the rod elements  20 . Rod elements  20  and crossbar  22  sever as a holder for a cutting wire  26 . Together, rod elements  20 , crossbar  22  and wire  26  are an operative tip of the electrocautery device.  
         [0076]     As further illustrated in  FIG. 2 , cutting wire  26  spans between the distal ends  27  of the rod elements  20 .  FIG. 1  shows the device  16  and the cutting wire  26  in a collapsed position for sliding through the channel  12  and tube  14 . The crossbar element  22  and rod elements  20  are pivotally connected together by hinge/pivot elements or pivots  28 . Similarly, the rod elements  20  are coupled to the push bars or wires  18  by pivots  32 .  
         [0077]     The device  16  has a handle mechanism  34  at the proximal end of the cutting device, as shown in  FIG. 5 , which is coupled to the push bars or wires  18 . The handle mechanism  34  is distally connected to elongate tube  14  and includes a lockable thumb ring  36 , slideable in perspective to finger rings  38 , and connected to push bars  18 . The thumb ring  36  is slideable as indicated by arrow  39 . A lock  40  may be used to lock the thumb ring  36  with respect to the finger rings  38 . The handle mechanism also includes an electrical connector  42 .  
         [0078]     The handle mechanism  34  may be connected at its proximal end, through the electrical connector  42 , to an electro-surgical generator. The push bars or wires  18  may also conduct electric current to the cutting mechanism, such as to the cutting wire  26 , so as to heat the cutting wire to provide a cauterizing effect when the wire is used to cut tissue as discussed below.  
         [0079]     The distal end of the device  16 , as shown in  FIG. 1 , is composed of elements that are capable of being collapsed into the distal segment of the elongate tube  14  while being deployed through the working channel  12  of the endoscope  10 . The cutting mechanism includes the rigid or semi rigid elements  20 , and  22  which, when fully deployed, form an “A” shape, as shown in  FIG. 3 , with the top of the “A” in slidable contact with the push bars or wires  18 . With reference to  FIG. 2 , the device  16  is pushed from the end of tube  14 , such as by motion of the thumb ring  36 . The motion of the thumb ring with respect to the finger rings causes one push bar or wire  18  to advance distally, as shown in  FIG. 2 , and the other push bar or wire  18  to retract proximally. The push bars or wires  18  move the rod elements  20 , which pivot with respect to the push bars or wires on pivots  32 . This motion of the rod elements  20 , in turn, causes the crossbar  22  to pivotally move on pivots  28  to span between the wire elements  20  and to cause the wire elements  20  to angle away from each other and to ultimately form the “A” shape as shown in  FIG. 3 . The cutting wire  26  is then stretched to span between the distal ends of the rod elements  20 .  
         [0080]     The crossbar  22  of the “A” is covered with an insulating heat shrink material and is connected to each leg (rod element  20 ) of the “A”. The bottom or most distal segments of the rod elements  20  forming the “A” are connected to the electrically conductive cutting wire, which may be a very thin stainless steel mono-filament. As shown in  FIGS. 1-3 , the device  16  is collapsed and contained in the endoscope  10 . When the device  16  is passed through the endoscope working channel  12  it is ejected from the distal end of the endoscope  10  and positioned near the tissue targeted for resection. As discussed above, the handle mechanism is pushed in the distal direction causing the push bars or wires to slide forward and open the cutting device to a use configuration by pushing the slidable connected rods  20  of the “A” down and the hinge connected crossbar  2  out forcing the lower portion of the “A” apart and the cutting wire to straighten and become firm. In that position, the push bars or wires  18  are aligned at their proximal ends, crossbar  22  is generally perpendicular to push bars or wires  18  and the cutting wire  26  is stretched taut and generally parallel to crossbar  22 . The rod elements  20  are angularly connected to push bars or wires  18 , crossbar  22  and cutting wire  26 . The cutting wire  26  may be guided in the depth of cut by the crossbar  22 .  
         [0081]     In the position as shown in  FIG. 3 , the handle mechanism is locked into this position maintaining consistent tension on the cutting wire. The distance between the crossbar and cutting wire is predetermined and maybe set at various heights, such as at approximately 3 mm for example.  
         [0082]      FIG. 4  depicts the cutting procedure in progress. The cutting wire  26  is placed slightly beyond the targeted tissue and cautery is applied as the heated cutting wire is drawn across a lesion  50  or other tissue. This action causes thin slicing through the tissue, such as a lesion or tumor, in the same fashion as a cheese cutter slicing through cheese. The preset distance of the cross bar  22  with respect to the cutting wire  26  prevents the cut from penetrating too deeply into the tissue. In order for the triangle or “A” shape structure to remain stationary and not rotate on its axis, it may be desirable to use a collar  52  or other structure (see  FIG. 3 ) at the distal end of the tube  14  so that the triangle remains positioned in a stable manner. The severed tissue  54  is then captured with a grasper or retrieval net and withdrawn for pathologic evaluation.  
         [0083]     Another embodiment of the cutting device is shown in  FIGS. 6-9 . The cutting device  60  is an electrocautery device similar to device  16  that is capable of being passed through the working channel  12  of an endoscope  10  as shown in  FIG. 6 . The device  60  also uses an elongate tube  14 , a handle mechanism  34  ( FIG. 10 ), and a push rod  64 , with a cutting mechanism at the distal end. The handle mechanism  34  may be connected at its proximal end to an electro-surgical generator through the connector  42 . The push rod or wire  64  may also conduct electric current to the cutting mechanism as discussed above for cautery cuts of tissue. The distal end of the device  60  is composed of an embodiment that is capable of being collapsed into the distal segment of the elongate tube  14  (catheter) while being deployed through working channel  12  of the endoscope  10 .  
         [0084]     The cutting device or assembly includes two opposing rigid segments  66  that, when fully deployed, form an A shape with the top of the A in slidable contact with the push bar or wire. The rigid segments  66  are connected to a spring, such as in the form of a spring biased arch structure  68  or other spring structure. In the illustrated embodiment, the arch structure is n shaped, connected to the Λ shape of the opposing rigid segments  66  to drive the segments apart. The spring biased arch structure  68  is constructed in such a way as to bias the legs open as shown in  FIGS. 7-8 . A cutting wire  70  spans between the distal ends of the rigid segments  66 . By actuation of the handle mechanism  34 , the cutting wire  70 , rigid segments  66 , spring biased arch structure  68  and push rod  64  emerge from the distal end of elongate tube  14  as shown in  FIG. 7 . As spring biased arch structure  68  emerges it opens, pushing rigid segments  66  apart at the distal ends, thereby stretching the cutting wire  70  therebetween. The cutting wire  70  can be an electrically conductive wire, such as a very thin stainless steel mono-filament. With reference to  FIG. 8 , an A shape is formed by the device  60 .  
         [0085]     As depicted in  FIG. 6 , when the triangle is housed in the elongate tube  14  or catheter in the pre-deployment position, the rigid segments  66  are situated in a generally parallel position with one another, and the arch structure  68  and cutting wire  70  are collapsed inside the elongate tube  14 . When the device is prepared for deployment, the handle is actuated causing the push-bar or wire to advance in the distal direction. This causes the two rigid triangle legs to be ejected from the catheter as demonstrated in  FIG. 7 . The spring biased arch structure  68  springs open, thereby separating the legs and straightening the distal cutting wire  70  at the base of the triangle ( FIG. 8 ).  
         [0086]     As illustrated in  FIG. 9 , when the cutting assembly  60  is in its fully open position ready for tissue resection, it is brought to the distal end of the target tissue  80 , pressed into the tissue and pulled along the surgical site while activating the cautery. This action causes thin slicing through the tissue  80 , such as a tumor, in the same fashion as a cheese cutter slicing through cheese, thereby forming webs or sheets of separated tissue. The cutting depth may be judged by the operator. An additional insulated wire  73  may be connected to both rigid segments  66 , the legs of the triangle, at a fixed distance from the cutting wire  70 . As demonstrated in  FIG. 8 , the connection of an insulated wire  73  could be formed proximate to where the spring biased arch is connected to the rigid legs. This second wire may serve as a gauge for judging the cutting depth as in the first embodiment. The device could be manufactured with or without this insulation wire; oftentimes physicians would like to use their own judgment concerning the depth of the cut. Furthermore, the lesion may not be the same thickness in all its various parts, and may require different depths of cutting.  
         [0087]      FIGS. 11-12  illustrate an alternative cutting device of the invention with an alternative arch structure  82 . The arch structure  68  is illustrated as a single piece. However, alternatively, the arch structure  82  might be multiple pieces coupled together to provide a spring bias to drive the segments  66  apart. Referring to  FIG. 12 , the arch structure or spring  82  might utilize two legs  84  that cooperate, such as with a tongue and groove relationship  86  to provide a spring bias. This configuration enhances the folding or collapsing of the distal cutting assembly into the elongate tube.  
         [0088]     Another alternative embodiment of the cutting device is shown in  FIGS. 13 and 14 . The cutting device  90  is an electrocautery device similar to device  60 , capable of being passed through the working channel of an endoscope. Like device  60 , this iteration of the device is passed through an elongate tube, possesses a handle mechanism and a push rod all not shown in  FIG. 13 . However, in this embodiment the push bar comprises a hollow tube  87 , which is split down the middle at its distal end into two longitudinally cut halves, comprising legs  88  of a wire holder (not separately designated) of the distal cutting assembly. The tubular push rod is made of a shape memory metal such as Nitinol. The inverted “V” shape that is created by cutting the tube as described above is baked into the shape memory metal such that when it is in an unconfined space, it takes on the shape of the inverted “V”. When it is stored in the pre-deployment configuration inside the elongate tube, the inverted “V” is closed, enabling storage of the distal assembly inside the elongate tube. The cutting wire  92 , which may be a stainless steel monofilament, traverses through the tubular structure originating from its most proximal end, then runs down one leg  88  of the inverted “V”, forms a taut straight line at the base of the V when it is in its open position, and runs up the second leg  88  of the inverted V back into the tube  87 . The proximal ends of the cutting wire traverse through the entire hollow push rod only to exit in the handle assembly, where they are operatively engaged with the electric connector. The reason for separating the wire from the shape memory material is that Nitinol and other shape memory materials are poor and unpredictable conductors of electricity. Therefore, by running the cutting wire through the legs of the inverted “V”, the operator is assured of consistent cutting action. The cutting wire may be affixed to the distal aspects of the inverted “V” legs by traversing through holes  94  or by crimping them onto the distal aspect of the legs. The legs are then covered by a nonconductive heat shrink material  96  as shown in  FIG. 14 , which serves to contain the cutting wire, and render the legs  88  non-conductive.  FIGS. 13 and 14  show this iteration of the device in the open, deployed configuration, ready for the cutting operation. When the distal assembly is stored in the elongate tube, the legs of the inverted “V” come together; the cutting wire collapses and is situated in a folded fashion distal to the tips of the legs, and is thereby stored inside the elongate tube  14 .  
         [0089]     Yet another preferred embodiment of the device is illustrated in  FIGS. 15-19 .  FIG. 15  demonstrates the entire device  100 , whereby elongate tube  14  houses the cautery device for passage though the channel of the endoscope. A set of opposing jaws  102  are located at the distal end of the device. An electrically conductive wire  104  is held by and operatively connected to the distal tips  106  of the jaws  102 . One ore more electrically conductive push-pull wires  110  shown in  FIG. 19  are operably connected to links  112 , which in turn move jaws  102  distally. Push pull wires  110  are also operatively connected to handle mechanism  108  proximally. In the embodiment illustrated in  FIG. 15 , handle assembly  108  includes finger rings  114  which serve to allow for traction while the thumb ring  116  is being pulled towards the operator. This action causes a pulling of the push-pull wires  110 , which are proximally connected to thumb ring  116  and to the proximal jaw-links  112  distally. When thumb ring  116  is pulled, a ratcheting mechanism  118  coupled with locking mechanism  120  ensures locking of the wires  110  in the taut position, rendering the jaws  102  in their maximal open position, and the attached cutting wire  104  in its taut straight cutting configuration.  
         [0090]      FIG. 16  illustrates another scissor handle mechanism  122 . When the finger rings  124  are pulled open, the push-pull wire or wires  110  are pulled, causing the jaws  102  to open. The ratcheting mechanism  126  allows for continuous stable opening of the scissor handle, while the locking mechanism  128  locks the device in its operative open configuration ready for cutting. Electric connector  130  is coupled with push-pull wires  110 , whereby when connected to an electric generator electricity flows through wires  110 , into electrically conductive links  112 , into jaws  102 , and finally into cutting wire  104 .  FIG. 17  demonstrates the distal assembly  132  in its fully open cutting configuration.  FIG. 18  demonstrates the distal assembly  132  in a partially open configuration, and  FIG. 19 , in a closed configuration. As in the case of device  60 , the cutting wire is collapsed and folded, and is contained within the elongate tube  14  while in the pre-deployment configuration. When the device is prepared for use, the scissor handle  122  is ratcheted open to the maximum extent, and locked into position. The distal cutting assembly  132  is brought to the area to be resected, and while cautery is being activated is pulled across the lesion towards the operator, thus shaving a slice of thin tissue. The tissue is then retrieved and sent for pathologic examination.  
         [0091]      FIGS. 20-26  depict another tissue-shaving cutting and cauterizing device for use in an endoscopic procedure.  FIG. 20  demonstrates an operative tip  141 , at the distal end of the device, in an open, ready to cut position. A set of opposing jaws or arms  142   a  and  142   b  are located at the distal end of the device. Jaws  142   a  and  142   b  are hingedly secured to each other by a pivot pin  144 . Pivot pin  144  is operatively connected to a pronged collar  145  which is permanently attached to an elongate instrument shaft such as tubing  14  and provides for a secure pivot point for jaws  142   a  and  142   b . Jaws  142   a  and  142   b  are configured into right and left halves so that the distal tips align with one another in an open use configuration or a closed deployment or insertion configuration. An electrically conductive wire  104  is operatively connected to the distal tips of the jaws  142   a  and  142   b , for instance, via insulating plugs  143   a  and  143   b . This wire  104  is contiguous with push pull wires  110 , which are proximally connected to a handle mechanism (not shown).  FIG. 21  depicts the assembly from another angle. As cutting wire  104  is pulled proximally and tightened, jaws  142   a  and  142   b  are pulled open and the wire becomes taut. As cutting wire  104  is pushed, the jaws  142   a  and  142   b  close, and the cutting wire relaxes as shown in  FIGS. 22 and 23 .  
         [0092]     Jaws or arms  142   a  and  142   b  constitute a holder member with wire  104  extending between spaced tips of jaws  142   a  and  142   b  in the use configuration ( FIGS. 20 and 21 ). Jaws  142   a  and  142   b  and wire  104  form an operative tip that is introduced in a collapsed insertion configuration ( FIGS. 22 and 23 ) through an endoscope working channel into a patient. At an operative site, instrument shaft or tubing  14  is pushed in the distal direction along the endoscope working channel so that jaws  142   a  and  142   b  emerge from the distal end of the working channel. Pusher wire  110  is then shifted in the distal direction to open jaws  142   a  and  142   b  and hold cutting and cauterizing wire  104  in a taut and straight configuration shown in  FIGS. 20 and 21 . The cutting and cauterizing instrument and endoscope are manipulated from outside the patient to place the straightened wire  104  into contact with a target tissue mass such as a sessile polyp or Barrett&#39;s esophagus formations. The cutting and cauterizing instrument is moved along the tissue mass to slice a thin layer, sheet or web of organic tissue off of the tissue mass. The process is repeated until the entire mass is removed. Because the shaving of the tissue is an iterative process, care can be easily taken to avoid a perforation of the organ wall (e.g., colon or esophagus).  
         [0093]     Jaws or arms  142   a  and  142   b  define a Y- or V-shape and extend at an acute angle relative to one another in the use configuration ( FIGS. 20 and 21 ). Jaws or arms  142   a  and  142   b  are pivoted away from one another to open the holder from the collapsed insertion configuration ( FIGS. 22 and 23 ) to the spread-out use configuration ( FIGS. 20 and 21 ) and to stretch the wire element  104  from a loose or flaccid loop ( FIGS. 22 and 23 ) to a straight and taut line ( FIGS. 20 and 21 ). This conformational change may be effectuated by simply pulling push rod or wire  110  in the proximal direction. A crimping element  147  enables a transfer of tensile forces to both jaws  142   a  and  142   b , via wire segments  149   a  and  149   b  that extend from crimping element  147  along respective jaws or arms  142   a  and  142   b.    
         [0094]     As depicted in  FIGS. 24-26 , a jaw  150  utilizable in the cutting and cauterizing instrument of  FIGS. 20-23  includes a lever arm  152 , a pivot-pin retaining bearing  154 , and a guide tube  156  which is traversed by a wire segment  149   a  or  149   b  ( FIGS. 20 and 22 ). A notch or recess  158  is formed at a free end of arm  152  for turning the wire segment  149   a  or  149   b  into wire  104 .  
         [0095]      FIG. 27  shows a modification of the cutting and cauterizing instrument of  FIGS. 20-23  where a helical spring member  160  is provided for biasing jaws  142   a  and  142   b  towards the open or use configuration. A lock (not shown) may provided on the handle or actuator assembly (not shown) for maintaining the jaws  142   a  and  142   b  in a closed or collapsed configuration during insertion of the instrument into the patient.  
         [0096]      FIGS. 28-32  illustrate an endoscopic cutting and cauterizing instrument  161  including an elongate flexible tubular instrument shaft  162  insertable through a working channel  164  ( FIG. 32 ) of an endoscope  166 . The instrument also includes a holder member  168  provided at a distal end of the instrument shaft  162 , and a cutting and cauterization wire element  170  connected at a distal end to a distal tip  172  of the holder member. In a use configuration of the holder member  168  and the wire element  170 , the wire element extends taut in a straight line between distal tip  172  and a bend, joint or articulation  174  of the holder member, as shown in  FIGS. 28, 31 , and  32 .  
         [0097]     In the use configuration, holder member  168  has a V-shaped configuration with a pair of arms  176  and  178  extending at an acute angle a 1  ( FIG. 31 ) relative to one another. At its distal end, wire element  170  extends in a straight line from the one arm  176  of the holder member  168  to another arm  178  thereof. The arms  176  and  178  of the holder member are pivotably connected to one another at a bend, joint or articulation  180 . Arm  178  is connected to shaft  162  via bend, joint or articulation  174 .  
         [0098]     In an insertion configuration illustrated in  FIG. 29 , arms  176  and  178  are disposed linearly exemplarily inside an outer tubular introduced sheath  182  that is in turn inserted inside the working channel  164  of the endoscope  166 . After insertion of distal end portion of the endoscope  166  into a patient, an operative tip  184  of the cutting and cauterizing instrument  161  is ejected from the endoscope working channel  164 . The operative tip  184 , including arms  176  and  178  and the distal end portion or wire element  170 , is then reconfigured from the linear insertion configuration ( FIG. 29 ) to the bent or folded use configuration ( FIGS. 28, 31 ,  32 ).  
         [0099]     Arms  176  and  178  of holder member  168  are tubes that may incorporate a coiled spring member internally (represented by concatenated circles  186 ) that provides the holder member  168  with a spring bias tending to straighten arms  176  and  178  into the linear insertion configuration of  FIG. 29 . Arms  176  and  178  may be continuously formed with one another and with at least a distal end portion of instrument shaft  162 . More particularly, arms  178  and  176  may be integrally formed with instrument shaft  162 . This form of holder member  168  is one continuous catheter that has a small spring  186  inside it extending from the distal end to the most proximal end of arm  178 . When in the pass-through configuration, the catheter is straight.  
         [0100]     Upon the ejection of holder member  168  from working channel  164  of endoscope  166  (or from tubular introducer sheath  182 , itself slidably inserted inside working channel  164 ), holder member  168  is folded first at joint, bend point, or articulation  180  to form arms  176  and  178  into a triangular or V-shaped configuration  188  shown in  FIG. 30 . This conformation change may be effectuated by pulling on the wire element  170 , which extends along shaft  162  to a handle  189  ( FIG. 28 ) at the proximal end of the instrument assembly. Subsequently, holder member  168  is folded at joint, bend point, or articulation  178  to fold V-shaped configuration  188  against tubular instrument shaft  162  to form the use configuration shown in  FIGS. 28, 31 , and  32 . This conformation change may be effectuated by pulling on an auxiliary wire or thread element  190 , which extends from joint, bend point, or articulation  180  through a hole  191  into outer tubular introducer sheath  182  and to handle  189 .  
         [0101]      FIG. 32  depicts use of the instrument assembly  161  to cut thin layers, sheets, or webs  192  of organic tissue from a sessile polyp or other tissue mass  194  along a wall  196  of an internal organ  198  such as the colon or esophagus. Current is conducted through wire  170  into the patient&#39;s tissues during a pulling of the operative tip  184  and particularly wire  170  through tissue mass  194  generally parallel to wall  196  and in a proximal direction towards a distal end face  200  of endoscope  166 .  
         [0102]     As illustrated in FIGS.  33 ,  34 A- 34 D, and  35 A- 35 C, a medical cutting and cauterizing device  202  comprises an elongate instrument shaft  204  insertable through a working channel  206  of an endoscope  208 , a holder member  210  provided at a distal end of the instrument shaft, and a cutting and cauterization wire element  212  connected to the holder member. Wire element  212  may be made of tungsten. Wire element  212  may alternatively be made of a semi-rigid stainless steel, and cut through tissue without cauterization action. Wire element  212  extends between spaced points of holder  210  member in a use configuration of the holder member and the wire element. In this embodiment, the use configuration of holder member  210  and wire element  212  is identical to the insertion configuration, except for the location of the cutting and cauterizing device  202  relative to endoscope  208  and particularly relative to a leading or distal end face  214  thereof. This is to say that holder member  210  and wire element  212  are substantially rigid components connected to one another in a fixed configuration.  
         [0103]     Holder member  210  typically but not necessarily has a V-shaped configuration with a pair of arms  216  and  218  extending at an acute angle a 2  relative to one another. Wire element  212  extends along a circular arc from a tip or free end of arm  216  of the holder member to a tip or free end of arm  218 . Holder member  210  and wire element  212  comprise an operative tip  219  of instrument  202  and lie in a plane oriented perpendicularly to instrument shaft  204 , at least during an insertion or deployment procedure. More particularly, holder member  210  and wire element  212  are disposed along and flush against distal end face  214  of endoscope  208  and inserted into a patient while riding on the distal end face of the endoscope insertion member  220 .  
         [0104]     As shown in  FIGS. 34A-34D , holder member  210  may be removably connectable to the end of instrument shaft  204 . At the commencement of an endoscopic procedure, instrument shaft  204  is inserted into working channel  206  of endoscope  208  from the proximal end thereof. As shown in  FIG. 34A , instrument shaft  204  is provided at a distal end with an internally threaded recess  222 , while holder member  210  includes a stem  224  provided with an externally threaded pin  226 . As indicated by an arrow  228  in  FIG. 34B , holder member  210  is screwed onto the distal end of instrument shaft  204  as it protrudes from the distal end of endoscope working channel  206  prior to and in preparation of insertion into the patient. After formation of this connection, instrument shaft  204  is pulled in the proximal direction, as indicated by an arrow  230  in  FIG. 34C , until holder member  210  and wire element  212  are snug against the leading or distal end face  214  of the endoscope insertion member  220 , as shown in  FIG. 34D . Holder member  210  and wire element  212  are dimensioned so that the wire element is seated along a periphery or rim  232  of front or distal end face  214  and so that arms  216  and  218  miss or avoid various working elements on distal end face  214 , including, for instance, an illumination outlet  234 , a lens  236 , working channels  238 , an irrigation fluid outlet port  240 , air channel etc. ( FIG. 34D ).  
         [0105]     Endoscope insertion member  220  is inserted into the patient with the operative tip  219  (holder member  210  and cauterizing wire element  212 ) engaging or snugly touching the distal end face  214  of the endoscope  208 , as shown in  FIGS. 34D and 35A . After the scope has reached a diagnostic or surgical site inside the patient, for instance, a tissue mass  242  ( FIG. 35A ) such as in Barrett&#39;s esophagus with a dysplastic growth, shaft  204  is pushed in the distal direction along the endoscope working channel  206  so that operative tip  219  is separated from distal end face  214  of the endoscope insertion member  220 , as shown in  FIGS. 34C and 35B . Then, instrument  202  and endoscope  208  are manipulated form outside the patient to bring wire element  214  into engagement with tissue mass  242 . Wire element  212  is drawn into and along tissue mass  242  to remove a thin layer or web  244  of the tissue, as shown in  FIG. 34B . During the motion of wire element  212  through tissue mass  242 , electrical current is conducted into the wire element to facilitate a cutting and cauterizing of the tissue. The drawing of wire element  212  into and along the tissue mass  242  may then include pulling the holder member  210  via shaft  204  from outside the patient to draw the wire element towards a distal end face of the endoscope. Alternatively, the entire scope with shaft  204  and holder member  210  entrained thereto may be moved in the proximal direction. In certain cases, the motion may be that of a pushing away rather than pulling of either the endoscope, the cutting device or both. After the separation of tissue layer or web  244 , as shown in  FIG. 35C , the process may be repeated until the entire undesirable tissue mass  242  is removed from organ wall  245 . A retrieval net or other device (not shown) may be used to remove the separated tissue slices or webs  244  from the patient.  
         [0106]     As depicted in  FIGS. 36A and 36B , a cutting and cauterizing instrument or device  246  as described above with reference to  FIGS. 33-35C  may be provided with a joint or articulation  248  that enables a user to pivot an operative tip  250  from a transverse orientation ( FIG. 36A ) relative to an instrument shaft  252  to a parallel or longitudinal orientation ( FIG. 36B ) relative to the instrument shaft. In the transverse orientation, the operative tip  250 , including a Y-shaped holder  254  with a pair of arms  256  and  258  and an arcuate wire element  260  extending between the arms, is disposable in contact with a front or distal end face of an endoscope (not shown). In the parallel orientation, the operative tip  250  extends in a plane (plane of drawing  FIG. 36B ) that is parallel to a longitudinal axis  262  of instrument shaft  252 . Operative tip  250 , including holder  254  and a stem piece  264 , may be spring biased towards the transverse orientation. Pivoting of the operative tip  250  to the parallel orientation is effectuated, for instance, by sliding shaft  252  axially relative to a surrounding sheath  266 . As joint or articulation  248  is moved into sheath  266 , stem piece  264  assumes a collinear relationship with shaft  252 . In another embodiment, one or more wires or rods (not shown) may extend along shaft  252  to a distal end of stem piece  264  for exerting a torque thereon. The wires or rods may be alternately pushed or pulled, to change the orientation of the operative tip  219  from transverse to parallel and back again.  
         [0107]     A metal collet  268  may be provided at the distal end of sheath  266  to facilitate the transformation from the transverse orientation of  FIG. 7A  to the parallel orientation of  FIG. 7B . When the endoscopist is ready to pull the endoscope  208  out of the patient, operative tip  219  may stay in the parallel position, just as a cauterization snare with a pouch and a polyp may be pulled out without creating a problem.  
         [0108]     As depicted in  FIGS. 37A through 37C , a cutting and cauterizing instrument or device  270  as described above with reference to  FIGS. 33-35C  may be provided with a joint or articulation  272  that enables a user to pivot an operative tip  274  from a transverse orientation ( FIG. 37A ) relative to an instrument shaft  276  to a parallel or longitudinal orientation ( FIG. 37B ) relative to the instrument shaft. In the transverse orientation, the operative tip  274 , including a Y-shaped holder  278  with a pair of arms  280  and  282  and an arcuate wire element  284  extending between the arms, is disposable in contact with a front or distal end face of an endoscope (not shown). In the parallel orientation, the operative tip  274  extends in a plane (plane of drawing  FIG. 37B ) that is parallel to a longitudinal axis  286  of instrument shaft  276 . Operative tip  274 , including holder  278  and a stem piece  288 , are maintained in either the transverse orientation ( FIG. 37A ) or the parallel or straightened orientation by an elongate elastic member  290  that extends through a longitudinal bore or channel (not separately depicted) in instrument shaft  276  and through a longitudinal bore or channel (not shown) in stem piece  288 . Pivoting of the operative tip  274  to the straightened orientation is effectuated, for instance, by sliding shaft  276  axially relative to a surrounding sheath  292 . As joint or articulation  272  is moved into sheath  292 , stem piece  288  assumes a collinear relationship with shaft  276 .  
         [0109]     A distal end (not separated labeled) of instrument shaft  276  is provided with a transverse slot  294 , while a proximal end of stem piece  288  is optionally provided with a transverse slot  296 . Slots  294  and  296  accommodate and facilitate a shifting of elastic member  290  during a rotation of stem piece  288  from the transverse orientation to the parallel or straightened orientation.  
         [0110]     Wire element  212  may be constructed as a semicircle, or ¾ of a circle, and even as a straight cutting wire. The arcuate shape of wire element  212  is optimal for working in the esophagus, which has a rather restricted, circular lumen. The lesion may be removed by bringing the instrument below the lesion, and slowly burning off thin layers of tissue. The process may be quite controlled as to depth and breath. Clean margins are now created, no gaps need occur, and the muscularis need never be invaded and breached.  
         [0111]     The EMR procedure sometimes requires injection of saline to raise the area for creating a buffer, or for injection of dye to mark the spot. It is therefore advantageous to provide either a double lumen that would house the shaft and instrument  202  in one lumen and a needle in another, or one lumen that would house them both. A snare with a web member may also be included in the assembly, preferably in a second or third lumen if the web member is to include a tether.  
         [0112]     Instrument  202 , as well as the other wire-implemented cutting instruments disclosed herein, is quite advantageous for EMR of sessile colonic polyps. The procedure may be performed as described above. The endoscope  208  can be bent 360 degrees in a circular motion, allowing for good contact and control. However, it may become desirable at a certain point, especially in the case of colonic polyps located in and around a bend in the colon or other lesions that are difficult to reach, to have the operative tip  219  device convert from a perpendicular (transverse) to a vertical (parallel) position, as described hereinabove with reference to  FIGS. 36A and 36B . During insertion of an endoscope with instrument  202 , the operative tip  219  cannot be disposed in a parallel or vertical position as such a position will block the endoscopist&#39;s view and interfere with insertion of the endoscope. Instead, the operative tip  219  must lie flat in an orientation perpendicular to the working channel and the instrument shaft, along the end face of the endoscope.  
         [0113]     As it is important that the operative tip  219  does not move out of place while the endoscope  108 ,  208  is being inserted into the patient, stems  124 ,  224  and posts or arms  116 ,  216 ,  218  are constructed such that there is a snug fit into the working channel of the distal end of the instrument shaft, such as stem  264 . This is accomplished by making this distal instrument shaft portion larger that the main body of the shaft. In addition, by pulling the device  102 ,  202  until the operative tip  119 ,  219  is in snug engagement with the endoscope tip, there is no opportunity for the distal assembly to be displaced during the insertion procedure.  
         [0114]     A device may be offered with one shaft with handle, and several working-end assemblies to be attached as per the requirement of the surgeon. The handle assembly includes a plug for cautery, which is activated when surgery is performed. This idea is novel in the art of interventional flexible endoscopy: there are no devices at present that may be operated through the working channel of a flexible endoscope, which possess a substantially rigid end-working assembly that is larger than the working channel. This invention enables the use of such a larger end-assembly by passing the shaft of the instrument into the endoscope&#39;s working channel, and then attaching the end assembly distally prior to insertion into the patient. The end assembly must be “invisible” to the endoscopist until he or she are ready to use it. At that point the device is pushed forward, comes into view, and may be utilized for the operation.  
         [0115]     Although the invention has been described in terms of particular embodiments and applications, one of ordinary skill in the art, in light of this teaching, can generate additional embodiments and modifications without departing from the spirit of or exceeding the scope of the claimed invention. Accordingly, it is to be understood that the drawings and descriptions herein are proffered by way of example to facilitate comprehension of the invention and should not be construed to limit the scope thereof.