fig1 illustrates a tissue resection device for performing a submucosal medical procedure to resect a portion of the mucosal layer in the digestive tract of a mammal according to an embodiment of the present invention . the tissue resection device 10 includes an elongate catheter 12 having a distal end 14 , a proximal end 16 and a lumen extending therethrough . handle assembly 18 is coupled to the proximal end 16 of catheter 12 and electrosurgical loop cutter wire 19 is positioned at the distal end . handle assembly 18 includes a slide assembly 20 which is fixedly coupled to the proximal end of the cutting wire actuator 22 of the electrosurgical loop cutter wire 19 . slide assembly 20 includes an electrical connector 24 which is in electrical contact with proximal end 22 and facilitates the coupling of an electrosurgical generator to supply energy to cutter wire 19 . fig2 a and 2b illustrate the distal end of tissue resection device 10 in more detail showing a partial cross section of elongate first and second tubular tissue guides 26 and 28 respectively . each of the tubular tissue guides are biased outwardly . as shown the first and second tubular tissue guides also each have a longitudinally extending slot , 30 and 32 respectively , extending through the wall . loop cutter wire 19 extends through the slots of the tissue guides and portions of the loop cutter wire 19 positioned within the lumens of the tissue guides are supported by tubular wire guides 34 and 36 , respectively . referring to fig1 , 2 a and 2 b , the proximal ends of wire guides 34 and 36 and loop 19 are fixedly coupled to cutting wire actuator 22 forming a “ y ” configuration ( not shown ). when the handle slide assembly 20 is moved distally the cutting wire actuator 22 causes the wire guides 34 and 36 along with loop cutter wire 19 to move distally . the loop cutter wire 19 advances distally along a path defined by the slots 30 and 32 in the first and second tissue guides 26 and 28 . fig3 a shows a perspective view of a portion of the digestive tract 40 having a desired region of previously dissected mucosal tissue 42 , un - dissected mucosal tissue 44 and the underlying muscle layer 46 , using methods and described in us patent application publication no : us 2009 / 0018602 a1 entitled “ methods and systems for performing submucosal medical procedures ” to mitelberg , et al . and assigned to the same assignee as the present invention and herein incorporated in its entirety by reference . also shown in this figure is an endoscope 48 positioning the distal end 14 of catheter 12 of tissue resection device 10 adjacent a mucosal opening 50 . fig3 b through 3e illustrate a method of operating a mucosal resection device to perform a submucosal medical procedure to remove a desired region of the mucosal layer in a mammal according to an embodiment of the present invention . a first tissue guide 26 is positioned through the mucosal opening 50 to extend in the submucosal space beneath mucosal layer 42 . the second tissue guide 28 is positioned above mucosal layer 42 . as electrosurgical loop cutter wire 19 is energized and advanced , tissue guides 26 and 28 are brought closer together and cutter wire 19 cuts the tissue of mucosal layer 42 along the path defined by the slots . once the movement of the cutter wire 19 stops , the supply of electrosurgical energy is halted . cutter wire 19 is retracted to allow tissue guides 26 and 28 to open and the entire system is advanced forward to begin another cutting sequence . the number of cutting sequences required is dependant upon the size of the area to be resected , the length of the tissue guides and associated slots . this process may be used to completely remove certain sized lesions depending on the curvature of the tissue guides . fig4 a through 4c illustrate a partial resection of mucosal layer 42 using a tissue resection device of the present invention and subsequent method of complete removal using additional devices . the resultant cutting path 52 is show after multiple sequences using tissue resection device 10 . the remaining dissected mucosal layer 42 may be manipulated using tissue grasper 58 and ensnared using an endoscopic snare 60 . the loop 62 of the snare 60 is positioned around the remaining attached portion of mucosal layer 42 . the snare may then be reduced in diameter and energized to complete the resection of mucosal layer 42 . novel instruments , systems and methods have been disclosed to perform submucosal medical procedures in the digestive tract of a mammal . although preferred embodiments of the invention have been described , it should be understood that various modifications including the substitution of elements or components which perform substantially the same function in the same way to achieve substantially the same result may be made by those skilled in the art without departing from the scope of the claims which follow .
instruments and methods are provided for performing submucosal medical procedures in a desired area of the digestive tract using endoscopy . the instruments include a mucosal resection device , a tissue grasper and a snare . systems include a combination of one or more of such instruments . embodiments of various methods for performing the procedures are also provided .