Endoscope having a guide tube

Abstract

An endoscope having a guide tube is described herein. The assembly has an endoscope which is slidably insertable within the lumen of a guide tube. The guide tube is configured to be rigidizable along its entire length from a relaxed configuration. The endoscope has a steerable distal portion to facilitate the steering of the device through tortuous paths. In the relaxed configuration, a portion of the guide tube is able to assume the shape or curve defined by the controllable distal portion of the endoscope. Having assumed the shape or curve of the endoscope, the guide tube may be rigidized by the physician or surgeon to maintain that shape or curve while the endoscope is advanced distally through the tortuous path without having to place any undue pressure against the tissue walls.

1 - 19 . (canceled)  
     
     
         20 . A method for advancing a first diagnostic or therapeutic instrument having a steerable distal tip into a natural or artificial opening in the body, the method comprising: 
 providing access into a natural or artificial opening in the body using an overtube comprising an elongated portion having a distal opening, a lumen extending therethrough to permit passage of the first diagnostic or therapeutic instrument, and a flexible distal region, and an atraumatic tip disposed on the flexible distal region;    inserting the first diagnostic or therapeutic instrument through the lumen so that the steerable distal tip is aligned with the flexible distal region; and    navigating the first diagnostic or therapeutic instrument together with the overtube through the portion of the body accessed by the natural or the artificial opening by steering the steerable distal tip of the first diagnostic or therapeutic instrument, thereby deflecting the flexible distal region of the overtube.    
     
     
         21 . The method of  claim 20  further comprising: 
 locking the overtube in a bent configuration; and    advancing the first diagnostic or therapeutic instrument through the lumen of the overtube in the bent configuration.    
     
     
         22 . The method of  claim 21  wherein the overtube comprises a plurality of nestable elements, and a tensioning mechanism that selectively applies a clamping load to the plurality of nestable elements, and locking the overtube in a bent configuration comprises actuating the tensioning mechanism.  
     
     
         23 . The method of  claim 21  wherein the overtube comprises a plurality of links, each link having a bore that defines the lumen of the overtube, and locking the overtube in a bent configuration comprises applying a clamping load to the plurality of links.  
     
     
         24 . The method of  claim 20  further comprising deflecting a portion of the body accessed through the natural or the artificial opening with the atraumatic tip so that tissue is not caught or pinched when the first diagnostic or therapeutic instrument is translated through the distal opening.  
     
     
         25 . The method of  claim 20 , wherein a second diagnostic or therapeutic instrument is disposed adjacent the first diagnostic or therapeutic instrument, the method further comprising: 
 advancing the second diagnostic or therapeutic instrument alongside the first diagnostic or therapeutic instrument in an overtube dimensioned to permit passage of a second diagnostic or therapeutic instrument alongside the first diagnostic or therapeutic instrument.