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 . (canceled)  
     
     
         2 . Apparatus for advancing a first diagnostic or therapeutic instrument into a hollow body organ of unsupported anatomy, the apparatus comprising: a handle; an overtube coupled to the handle, the overtube having proximal and distal ends, an exterior surface, and an interior surface that defines a lumen extending between the proximal and distal ends to permit passage of the first diagnostic or therapeutic instrument; and a disposable sheath having a first portion that extends through the lumen to provide a barrier between the interior surface and the first diagnostic or therapeutic instrument and a second portion that extends over the exterior surface.  
     
     
         3 . The apparatus of  claim 2 , wherein the disposable sheath comprises a polymeric material.  
     
     
         4 . The apparatus of  claim 2 , wherein the first portion comprises a thin, flexible material.  
     
     
         5 . The apparatus of  claim 2 , wherein the overtube comprises a plurality of nestable links that each has a lateral wall.  
     
     
         6 . The apparatus of  claim 5 , wherein the plurality of nestable links are made from a material selected from the group consisting of polymers, metals, and combinations thereof.  
     
     
         7 . The apparatus of  claim 5 , wherein each one of the plurality of nestable links comprises a distal surface and a proximal surface.  
     
     
         8 . The apparatus of  claim 5 , further comprising: a plurality of tension wire bores extending through the lateral wall of each one of the plurality of nestable links; and at least one tension wire translatably disposed through one or more of the plurality of tension wire bores.  
     
     
         9 . The apparatus of  claim 5 , wherein each one of the plurality of nestable links comprises an integral lubricious liner.  
     
     
         10 . The apparatus of  claim 5 , wherein the overtube further comprises a flexible state that facilitates insertion of the overtube into a hollow body organ, and a rigid state wherein the overtube resists bending forces exerted on the interior surface during insertion or withdrawal of the first diagnostic or therapeutic instrument though the lumen.  
     
     
         11 . The apparatus of  claim 10 , further comprising a tensioning mechanism selectively operable to transition the overtube between the flexible and rigid states.  
     
     
         12 . The apparatus of  claim 11 , wherein the tensioning mechanism is selectively operable to transition the overtube between the flexible and rigid states without substantial proximal movement of the distal end of the overtube.  
     
     
         13 . The apparatus of  claim 12 , wherein the tensioning mechanism is configured to apply a distally-directed clamping load to the plurality of nestable links.  
     
     
         14 . The apparatus of  claim 11 , wherein the tensioning mechanism is configured to transition the overtube from the flexible state to the rigid state with a single actuation of the actuator.  
     
     
         15 . The apparatus of  claim 11 , wherein the tensioning mechanism is configured to transition the overtube between the flexible and rigid states with successive actuations of the actuator.