Abstract:
Apparatus and methods for attaching and forming enclosed inflatable members on an endoscope assembly ( 10 ) with a disposable sheath ( 103 ) are disclosed. In one embodiment, an apparatus includes a flexible and resilient cuff member ( 100 ) that is positioned on the outer surface of the disposable sheath and sealably and fixedly bonded to the sheath cover material ( 130 ) at the cuff edges to form an annular space ( 136 ) capable of being inflated. The inflatable member ( 100 ) formed thereby is inflated through a lumen ( 122 ) internal to the sheath that has an opening ( 134 ) into the interior annular space. The inflatable member may be inflated to exert a longitudinal force on the insertion tube ( 101 ), thereby moving the endoscope assembly along a body passage. Alternately, a sheath may include a plurality of inflatable cuffs that may be inflated to create an isolated space therebetween within the body passage.

Description:
REFERENCE TO RELATED APPLICATIONS  
       [0001]     Reference is made to U.S. Provisional Patent Application 60/542,680, filed Feb. 9, 2004 entitled “MICRO-ROBOT AND ACCESSORIES FOR ENDOSCOPY AND IN-PIPE LOCOMOTION” and to U.S. Provisional Patent Application 60/559,461, filed Apr. 6, 2004 entitled “DEVICES, ACCESSORIES AND METHODS FOR ENDOSCOPY AND IN-PIPE PROPAGATION”, the disclosures of which are hereby incorporated by reference and priority of which is hereby claimed pursuant to 37 CFR 1.78(a) (4) and (5)(i). 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to endoscopy generally and more particularly to locomotive endoscopes.  
       BACKGROUND OF THE INVENTION  
       [0003]     The following U.S. patent Documents are believed to represent the current state of the art:  
         [0004]     U.S. Pat. Nos. 4,040,413; 4,176,662 and 5,662,587 and  
         [0005]     U.S. Patent Application Publication No. 2002/0156347  
       SUMMARY OF THE INVENTION  
       [0006]     The present invention seeks to provide an improved locomotive endoscope.  
         [0007]     The terms “endoscope” and “endoscopy” are used herein in a manner somewhat broader than their customary meaning and refer to apparatus and methods which operate within body cavities, passageways and the like, such as, for example, the small intestine, the large intestine, arteries and veins. Although these terms normally refer to visual inspection, as used herein they are not limited to applications which employ visual inspection and refer as well to apparatus, systems and methods which need not necessarily involve visual inspection.  
         [0008]     There is thus provided in accordance with a preferred embodiment of the present invention a locomotive endoscope assembly including a locomotive endoscope head, including a main portion extending along a longitudinal axis and having a first selectably inflatable balloon associated therewith and a selectably positionable portion, selectably axially positionable along the main portion and having a second selectably inflatable balloon associated therewith and a locomotive endoscope head controller controlling the operation of the locomotive endoscope head and being operative for controlling positioning of the selectably positionable portion relative to the main portion and selectable inflation of the first and second selectably inflatable balloons.  
         [0009]     In accordance with a preferred embodiment of the present invention at least one of the first and second selectably inflatable balloons includes a stretchable balloon. Preferably, the locomotive endoscope assembly also includes an endoscope body associated with the locomotive endoscope head. Optionally and preferably, an instrument channel at least partially extends through the locomotive endoscope head and the endoscope body.  
         [0010]     In accordance with another preferred embodiment of the present invention the locomotive endoscope head has a fixed length. Preferably, the endoscope body includes a multi-lumen tube. Alternatively or additionally, the endoscope body interfaces with the locomotive endoscope head controller.  
         [0011]     In accordance with yet another preferred embodiment of the present invention the locomotive endoscope assembly also includes an endoscopy system to which the locomotive endoscope head controller is connectable.  
         [0012]     In accordance with still another preferred embodiment of the present invention the multi-lumen tube includes at least one lumen operative for at least one of balloon inflation; positioning of the selectably positionable portion of the locomotive endoscope head; passage therethrough of at least one of an optical fiber and an electrical conductor bundle and fluid communication. Preferably, the multi-lumen tube includes at least one lumen operative for each of balloon inflation; positioning of the selectably positionable portion of the locomotive endoscope head and passage therethrough of at least one of an optical fiber and an electrical conductor bundle. Typically and preferably, the at least one lumen includes at least one first lumen operative for inflation of the first selectably inflatable balloon and at least one second lumen operative for inflation of the second selectably inflatable balloon.  
         [0013]     In accordance with a further preferred embodiment of the present invention the selectably positionable portion is slidably positionable with respect to the main portion. Preferably, the locomotive endoscope head includes at least one light source and at least one imaging sensor. Additionally or alternatively, the first selectably inflatable balloon includes at least two independently inflatable balloon portions. As a further alternative, the second selectably inflatable balloon includes at least two independently inflatable balloon portions. Preferably, the at least two independently inflatable balloon portions of the second selectably inflatable balloon are azimuthally offset with respect to the at least two independently inflatable balloon portions of the first selectably inflatable balloon.  
         [0014]     In accordance with a still further preferred embodiment of the present invention the locomotive endoscope head controller provides locomotive functionality adapted to sequentially displace the locomotive endoscope head through a generally tubular body portion. Preferably, the locomotive functionality includes functionality providing the following sequential operations: inflating the first selectably inflatable balloon, thereby anchoring the first selectably inflatable balloon to an interior surface of the generally tubular body portion; axially repositioning the selectably positionable portion and the second selectably inflatable balloon relative to the first selectably inflatable balloon; inflating the second selectably inflatable balloon, thereby anchoring the second selectably inflatable balloon to an interior surface of the generally tubular body portion; deflating the first selectably inflatable balloon, thereby unanchoring the first selectably inflatable balloon from the interior surface of the generally tubular body portion; and axially repositioning the first selectably inflatable balloon relative to the selectably positionable portion and the second selectably inflatable balloon. Optionally, the first selectably inflatable balloon is arranged with respect to the generally tubular body portion to be forward of the second selectably inflatable balloon. Alternatively, the second selectably inflatable balloon is arranged with respect to the generally tubular body portion to be forward of the first selectably inflatable balloon.  
         [0015]     There is also provided in accordance with another preferred embodiment of the present invention a locomotive endoscope assembly including a locomotive endoscope head, including a main portion extending along a longitudinal axis and having a first selectably radially extendible element associated therewith and a selectably positionable portion, selectably axially positionable along the main portion and having a second selectably radially extendible element associated therewith and a locomotive endoscope head controller controlling the operation of the locomotive endoscope head and being operative for controlling positioning of the selectably positionable portion relative to the main portion and selectable extension of the first and second selectably radially extendible elements.  
         [0016]     In accordance with a preferred embodiment of the present invention at least one of the first and second selectably radially extendible elements includes a selectably inflatable balloon. Preferably, the selectably inflatable balloon includes a stretchable balloon.  
         [0017]     In accordance with another preferred embodiment of the present invention the locomotive endoscope assembly also includes an endoscope body associated with the locomotive endoscope head. Preferably, an instrument channel at least partially extends through the locomotive endoscope head and the endoscope body. More preferably the locomotive endoscope head has a fixed length.  
         [0018]     In accordance with yet another preferred embodiment of the present invention the endoscope body includes a multi-lumen tube. Preferably, the endoscope body interfaces with the locomotive endoscope head controller. Additionally and preferably, the locomotive endoscope assembly also includes an endoscopy system to which the locomotive endoscope head controller is connectable.  
         [0019]     In accordance with still another preferred embodiment of the present invention the multi-lumen tube includes at least one lumen operative for at least one of radially extending element extension; positioning of the selectably positionable portion of the locomotive endoscope head; passage therethrough of at least one of an optical fiber and an electrical conductor bundle; and fluid communication. Preferably, the multi-lumen tube includes at least one lumen operative for each of radially extending element extension; positioning of the selectably positionable portion of the locomotive endoscope head; and passage therethrough of at least one of an optical fiber and an electrical conductor bundle. Typically and preferably, the at least one lumen includes at least one first lumen operative for extension of the first selectably radially extendible element and at least one second lumen operative for extension of the second selectably radially extendible element.  
         [0020]     In accordance with a further preferred embodiment of the present invention the selectably positionable portion is slidably positionable with respect to the main portion. Preferably, the locomotive endoscope head includes at least one light source and at least one imaging sensor.  
         [0021]     In accordance with yet a further preferred embodiment of the present invention the first selectably radially extendible element includes at least two independently extendible element portions. Additionally or alternatively, the second selectably radially extendible element includes at least two independently extendible element portions. Preferably, the at least two independently extendible element portions of the second selectably radially extendible element are azimuthally offset with respect to the at least two independently extendible element portions of the first selectably radially extendible element.  
         [0022]     In accordance with still a further preferred embodiment of the present invention the locomotive endoscope head controller provides locomotive functionality adapted to sequentially displace the locomotive endoscope head through a generally tubular body portion. Preferably, the locomotive functionality includes functionality providing the following sequential operations: extending the first selectably radially extendible element, thereby anchoring the first selectably radially extendible element to an interior surface of the generally tubular body portion; axially repositioning the selectably positionable portion and the second selectably radially extendible element relative to the first selectably radially extendible element; extending the second selectably radially extendible element, thereby anchoring the second selectably radially extendible element to an interior surface of the generally tubular body portion; retracting the first selectably radially extendible element, thereby unanchoring the first selectably radially extendible element from the interior surface of the generally tubular body portion; and axially repositioning the first selectably radially extendible element relative to the selectably positionable portion and the second selectably radially extendible element Optionally, the first selectably radially extendible element is arranged with respect to the generally tubular body portion to be forward of the second selectably radially extendible element Alternatively, the second selectably radially extendible element is arranged with respect to the generally tubular body portion to be forward of the first selectably radially extendible element.  
         [0023]     There is further provided in accordance with yet another preferred embodiment of the present invention an endoscope assembly including an endoscope head extending along a longitudinal axis and having a first plurality of selectably inflatable balloons associated therewith at at least one first axial location therealong and a second plurality of selectably inflatable balloons associated therewith at at least one second axial location therealong and an endoscope head controller being operative for controlling selectable inflation of the first and second pluralities of selectably inflatable balloons for selectable positioning of the endoscope head.  
         [0024]     In accordance with a preferred embodiment of the present invention the endoscope head controller is operative for controlling selectable inflation of the first and second pluralities of selectably inflatable balloons for selectable parallel off-center orientation of the endoscope head. Preferably, the endoscope head controller is operative for controlling selectable inflation of the first and second pluralities of selectably inflatable balloons for selectable tilted orientation of the endoscope head. Optionally and preferably, at least one of the first and second pluralities of selectably inflatable balloons includes a plurality of balloons distributed generally azimuthally about the endoscope head. More preferably, at least one balloon of the first and second pluralities of selectably inflatable balloons includes a stretchable balloon.  
         [0025]     In accordance with another preferred embodiment of the present invention the endoscope head includes a locomotive endoscope head. Preferably, the locomotive endoscope head includes a main portion extending along a longitudinal axis and associated with the first plurality of selectably inflatable balloons, and a selectably positionable portion, selectably axially positionable along the main portion and associated with the second plurality of selectably inflatable balloons.  
         [0026]     In accordance with still another preferred embodiment of the present invention the endoscope assembly also includes an endoscope body associated with the endoscope head. Preferably, an instrument channel at least partially extends through the endoscope head and the endoscope body. Optionally and preferably, the endoscope head has a fixed length.  
         [0027]     In accordance with a further preferred embodiment of the present invention the endoscope body includes a multi-lumen tube. Additionally or alternatively the endoscope body interfaces with the endoscope head controller. Preferably, the endoscope assembly also includes an endoscopy system to which the endoscope head controller is connectable.  
         [0028]     In accordance with yet a further preferred embodiment of the present invention the multi-lumen tube includes at least one lumen operative for at least one of balloon inflation; positioning of the selectably positionable portion of the endoscope head; passage therethrough of at least one of an optical fiber and an electrical conductor bundle; and fluid communication. Preferably, the multi-lumen tube includes at least one lumen operative for each of balloon inflation; positioning of the selectably positionable portion of the endoscope head; and passage therethrough of at least one of an optical fiber and an electrical conductor bundle.  
         [0029]     In accordance with a still further preferred embodiment of the present invention the selectably positionable portion is slidably positionable with respect to the main portion. Preferably, the endoscope head includes at least one light source and at least one imaging sensor. Additionally or alternatively, the first plurality of selectably inflatable balloons includes at least two independently inflatable balloon portions. As a further alternative, the second plurality of selectably inflatable balloons includes at least two independently inflatable balloon portions. Preferably, the at least two independently inflatable balloon portions of the second plurality of selectably inflatable balloons are azimuthally offset with respect to the at least two independently inflatable balloon portions of the first plurality of selectably inflatable balloons.  
         [0030]     In accordance with an additional preferred embodiment of the present invention the endoscope head controller provides locomotive functionality adapted to sequentially displace the endoscope head through a generally tubular body portion. Preferably, the locomotive functionality includes functionality providing the following sequential operations: inflating at least part of the first plurality of selectably inflatable balloons, thereby anchoring the first plurality of selectably inflatable balloons to an interior surface of the generally tubular body portion; axially repositioning the selectably positionable portion and the second plurality of selectably inflatable balloons relative to the first plurality of selectably inflatable balloons; inflating at least part of the second plurality of selectably inflatable balloons, thereby anchoring the second plurality of selectably inflatable balloons to an interior surface of the generally tubular body portion; deflating the first plurality of selectably inflatable balloons, thereby unanchoring the first plurality of selectably inflatable balloons from the interior surface of the generally tubular body portion; and axially repositioning the first plurality of selectably inflatable balloons relative to the selectably positionable portion and the second plurality of selectably inflatable balloons. Optionally, the first plurality of selectably inflatable balloons is arranged with respect to the generally tubular body portion to be generally forward of the second plurality of selectably inflatable balloons. Alternatively, the second plurality of selectably inflatable balloons is arranged with respect to the generally tubular body portion to be generally forward of the first plurality of selectably inflatable balloons.  
         [0031]     There is additionally provided in accordance with still another preferred embodiment of the present invention an endoscope assembly including an endoscope head extending along a longitudinal axis and having a first plurality of selectably radially extendible elements associated therewith at at least one first axial location therealong and a second plurality of selectably radially extendible elements associated therewith at at least one second axial location therealong and an endoscope head controller being operative for controlling selectable extension of the first and second pluralities of selectably radially extendible elements for selectable positioning of the endoscope head.  
         [0032]     In accordance with a preferred embodiment of the present invention the endoscope head controller is operative for controlling selectable extension of the first and second pluralities of selectably radially extendible elements for selectable parallel off-center orientation of the endoscope head. Preferably, the endoscope head controller is operative for controlling selectable extension of the first and second pluralities of selectably radially extendible elements for selectable tilted orientation of the endoscope head. Additionally or alternatively, at least one of the first and second pluralities of selectably radially extendible elements includes a plurality of radially extendible elements distributed generally azimuthally about the endoscope head.  
         [0033]     In accordance with another preferred embodiment of the present invention the endoscope head includes a locomotive endoscope head Preferably, the locomotive endoscope head includes a main portion extending along a longitudinal axis and associated with the first plurality of selectably radially extendible elements, and a selectably positionable portion, selectably axially positionable along the main portion and associated with the second plurality of selectably radially extendible elements.  
         [0034]     In accordance with yet another preferred embodiment of the present invention least one of the first and second pluralities of selectably radially extendible elements includes a plurality of selectably inflatable balloons. Typically and preferably, at least one balloon of the plurality of selectably inflatable balloons includes a stretchable balloon.  
         [0035]     In accordance with still another preferred embodiment of the present invention the endoscope assembly also includes an endoscope body associated with the endoscope head. Preferably, an instrument channel at least partially extends through the endoscope head and the endoscope body. Additionally or alternatively, the endoscope head has a fixed length.  
         [0036]     In accordance with a further preferred embodiment of the present invention the endoscope body includes a multi-lumen tube. Preferably, the endoscope body interfaces with the endoscope head controller. Additionally or alternatively, the endoscope assembly also includes an endoscopy system to which the endoscope head controller is connectable.  
         [0037]     In accordance with a still further preferred embodiment of the present invention the multi-lumen tube includes at least one lumen operative for at least one of: radially extending element extension; positioning of the selectably positionable portion of the endoscope head; passage therethrough of at least one of an optical fiber and an electrical conductor bundle; and fluid communication. Preferably, the multi-lumen tube includes at least one lumen operative for each of: radially extending element extension; positioning of the selectably positionable portion of the endoscope head; and passage therethrough of at least one of an optical fiber and an electrical conductor bundle.  
         [0038]     In accordance with an additional preferred embodiment of the present invention the selectably positionable portion is slidably positionable with respect to the main portion. Preferably, the endoscope head includes at least one light source and at least one imaging sensor. Additionally or alternatively, the first plurality of selectably radially extendible elements includes at least two independently selectably radially extendible elements. As a further alternative, the second plurality of selectably radially extendible elements includes at least two independently selectably radially extendible elements. Preferably, the at least two independently selectably radially extendible elements of the second plurality of selectably radially extendible elements are azimuthally offset with respect to the at least two independently selectably radially extendible elements of the first plurality of selectably radially extendible elements.  
         [0039]     In accordance with another preferred embodiment of the present invention the endoscope head controller provides locomotive functionality adapted to sequentially displace the endoscope head through a generally tubular body portion. Preferably, the locomotive functionality includes functionality providing the following sequential operations: extending at least part of the first plurality of selectably radially extendible elements, thereby anchoring the first plurality of selectably radially extendible elements to an interior surface of the generally tubular body portion; axially repositioning the selectably positionable portion and the second plurality of selectably radially extendible elements relative to the first plurality of selectably radially extendible elements; extending at least part of the second plurality of selectably radially extendible elements, thereby anchoring the second plurality of selectably radially extendible elements to an interior surface of the generally tubular body portion; retracing the first plurality of selectably radially extendible elements, thereby unanchoring the first plurality of selectably radially extendible elements from the interior surface of the generally tubular body portion; and axially repositioning the first plurality of selectably radially extendible elements relative to the selectably positionable portion and the second plurality of selectably radially extendible elements. Optionally, the first plurality of selectably radially extendible elements is arranged with respect to the generally tubular body portion to be generally forward of the second plurality of selectably radially extendible elements. Alternatively, the second plurality of selectably radially extendible elements is arranged with respect to the generally tubular body portion to be generally forward of the first plurality of selectably radially extendible elements.  
         [0040]     There is also provided in accordance with another preferred embodiment of the present invention apparatus for fluid supply to the interior of a portion of a tubular body portion including an element extending along a longitudinal axis and having at least one first selectably extendible tubular body portion sealing element associated therewith at a first axial location therealong and at least one second tubular body portion sealing element associated therewith at a second axial location therealong, a controller for selectably extending the at least one first and second tubular body portion sealing elements within a tubular body portion to define a sealed region therebetween and a fluid supply functionality supplying a fluid to the sealed region.  
         [0041]     In accordance with a preferred embodiment of the present invention at least one of the first and second tubular body portion sealing elements includes a selectably inflatable balloon. Preferably, the selectably inflatable balloon includes a stretchable balloon. More preferably, the selectably inflatable balloon includes a plurality of selectably inflatable balloon portions.  
         [0042]     In accordance with another preferred embodiment of the present invention the apparatus includes a locomotive endoscope head. Preferably, the apparatus for fluid supply also includes at least one fluid supply reservoir which is operative to supply the fluid to the sealed region. More preferably, the apparatus for fluid supply also includes fluid suction functionality for suctioning fluid from the sealed region.  
         [0043]     There is further provided in accordance with a further preferred embodiment of the present invention apparatus for fluid supply to the interior of a portion of a tubular body portion including a multi-lumen tube including at least first, second and third lumens extending therethrough, a forward selectably inflatable balloon in fluid communication with the first lumen, the forward selectably inflatable balloon being operative to seal the tubular body portion when inflated, a rear selectably inflatable balloon in fluid communication with the second lumen, the rear selectably inflatable balloon being operative to seal the tubular body portion when inflated, a fluid supply outlet, located intermediate the forward and rear selectably inflatable balloons, the outlet being in fluid communication with the third lumen and a controller for selectably inflating the first and second selectably inflatable balloons within a tubular body portion to define a sealed region therebetween and for supplying a fluid to the sealed region.  
         [0044]     There is additionally provided in accordance with still another preferred embodiment of the present invention an endoscope assembly including an endoscope tube having an instrument channel an endoscope tool arranged to travel along the instrument channel to a utilization location forward of the endoscope tube, the endoscope tool being slidably and sealingly located within the instrument channel and a fluid endoscope tool positioner for selectably pressurizing the instrument channel for providing fluid driven desired positioning of the endoscope tool along the instrument channel.  
         [0045]     In accordance with a preferred embodiment of the present invention the endoscope tool includes a piston-defining portion sealingly and slidably engaging the instrument channel.  
         [0046]     There is provided in accordance with a preferred embodiment of the present invention an endoscope assembly including a tube having at least one lumen and an endoscope tool arranged to travel through the at least one lumen, the endoscope tool including a stretchable selectably inflatable anchoring balloon.  
         [0047]     There is also provided in accordance with another preferred embodiment of the present invention an endoscope assembly including a tube having at least one lumen and an endoscope tool arranged to travel along the at least one lumen to a utilization location forward of the tube, the endoscope tool being selectably bendable forwardly of the tube.  
         [0048]     There is additionally provided in accordance with yet another preferred embodiment of the present invention an endoscope assembly including a tube having at least one lumen and an endoscope tool arranged to travel along the at least one lumen, the endoscope tool including a tool head and a multi-lumen tube connected to the tool head.  
         [0049]     In accordance with a preferred embodiment of the present invention the tube includes an endoscope tube. Preferably, the at least one lumen includes instrument channel. Additionally or alternatively, the multi-lumen tube includes at least a first lumen for inflation and deflation of the stretchable selectably inflatable anchoring balloon and a second lumen.  
         [0050]     In accordance with another preferred embodiment of the present invention the endoscope assembly also includes a tensioning wire which extends through the second lumen and which is operative for selectably bending the endoscope tool forwardly of the tube. Preferably, the endoscope tool is generally more flexible than the tube. Additionally or alternatively, the endoscope assembly also includes an endoscopy system to which the endoscope tube is connectable. As a further alternative, the endoscope assembly also includes an endoscope tool positioning control device and a balloon inflation/deflation control.  
         [0051]     In accordance with yet another preferred embodiment of the present invention the endoscope assembly also includes a tool port associated with the tube which is operative for insertion and removal of the endoscope tool.  
         [0052]     There is further provided in accordance with a further preferred embodiment of the present invention an endoscope assembly including an endoscope tube, the endoscope tube having a first stretchable selectably inflatable anchoring balloon adjacent a forward end thereof and an endoscope tool arranged to travel relative to the endoscope tube to a utilization location forward of the endoscope tube, the endoscope tool having a second stretchable selectably inflatable anchoring balloon adjacent a forward end thereof.  
         [0053]     In accordance with a preferred embodiment of the present invention the endoscope tool is selectably bendable forwardly of the endoscope tube. Optionally and preferably, the endoscope tool includes a tool head and a multi-lumen tube connected to the tool head. Additionally or alternatively, the multi-lumen tube includes at least a first lumen for inflation and deflation of the second stretchable selectably inflatable anchoring balloon and a second lumen.  
         [0054]     In accordance with another preferred embodiment of the present invention the endoscope assembly also includes a tensioning wire which extends through the second lumen and which is operative for selectably bending the endoscope tool forwardly of the endoscope tube. Preferably, the endoscope tool is generally more flexible than the endoscope tube. Additionally or alternatively, the endoscope assembly also includes an endoscopy system to which the endoscope tube is connectable. Additionally or alternatively, the endoscope assembly also includes an endoscope tool positioning control device and at least one balloon inflation/deflation control. As a further alternative, the endoscope assembly also includes a tool port associated with the endoscope tube which is operative for insertion and removal of the endoscope tool.  
         [0055]     There is yet further provided in accordance with yet another preferred embodiment of the present invention an endoscope assembly including a locomotive endoscope including a locomotive endoscope head and an endoscope body adapted for locomotion through a tubular body portion and for anchoring at a desired location in the tubular body portion and an endoscopy tool adapted for displacement along the endoscope body to a desired tool operation location.  
         [0056]     In accordance with a preferred embodiment of the present invention the endoscope assembly also includes at least one selectably radially extendible element associated with the locomotive endoscope head and adapted for anchoring the locomotive endoscope head at a desired location in the tubular body portion. Preferably, the at least one selectably radially extendible element includes a selectably inflatable anchoring balloon. Additionally or alternatively, the locomotive endoscope head includes at least one light source and at least one imaging sensor.  
         [0057]     In accordance with another preferred embodiment of the present invention the endoscope assembly also includes an overtube which is slidable along the endoscope body. Preferably, the overtube is associated with the endoscopy tool. Additionally or alternatively, the endoscope body is adapted to function as a guide wire for the overtube.  
         [0058]     In accordance with yet another preferred embodiment of the present invention the endoscopy tool includes a therapeutic tool. Alternatively, the endoscopy tool includes a diagnostic tool. As a further alternative, the endoscopy tool includes a surgical tool.  
         [0059]     There is also provided in accordance with another preferred embodiment of the present invention a locomotive endoscopy method including providing a locomotive endoscope head, including a main portion extending along a longitudinal axis and having a first selectably radially extendible element associated therewith and a selectably positionable portion, selectably axially positionable along the main portion and having a second selectably radially extendible element associated therewith and providing locomotion of the locomotive endoscope head by selectably positioning the slidable portion relative to the main portion and selectably extending and retracting the first and second selectably radially extendible elements.  
         [0060]     In accordance with a preferred embodiment of the present invention at least one of the first and second selectably radially extendible elements includes a selectably inflatable balloon. Preferably, the locomotive endoscopy method also includes positioning the locomotive endoscope head in a selectably non-parallel orientation relative to a tubular body portion by selectably non-identically extending at least two independently radially extendible element portions of the first selectably radially extendible element and at least two independently radially extendible element portions of the second selectably radially extendible element. Additionally or alternatively, the locomotive endoscopy method also includes positioning the locomotive endoscope head in a selectably off-center parallel orientation relative to a tubular body portion by selectably non-identically extending at least two independently radially extendible element portions of the first selectably radially extendible element and at least two independently radially extendible element portions of the second selectably radially extendible element.  
         [0061]     In accordance with another preferred embodiment of the present invention providing locomotion includes sequentially displacing the locomotive endoscope head through a generally tubular body portion. Preferably, providing locomotion includes sequentially displacing the locomotive endoscope head through at least one of a large intestine, a small intestine, an artery and a vein. More preferably, the sequentially displacing includes the following sequential operations: extending the first selectably radially extendible element, thereby anchoring the first selectably radially extendible element to an interior surface of the generally tubular body portion; axially repositioning the selectably positionable portion and the second selectably radially extendible element relative to the first selectably radially extendible element; inflating the second selectably radially extendible element, thereby anchoring the second selectably radially extendible element to an interior surface of the generally tubular body portion; deflating the first selectably radially extendible element, thereby unanchoring the first selectably radially extendible element from the interior surface of the generally tubular body portion; and axially repositioning the first selectably radially extendible element relative to the selectably positionable portion and the second selectably radially extendible element.  
         [0062]     There is additionally provided in accordance with yet another preferred embodiment of the present invention an endoscope positioning method including providing an endoscope head extending along a longitudinal axis and having a first plurality of selectably radially extendible elements associated therewith at at least a first axial location therealong and a second plurality of selectably radially extendible elements associated therewith at at least a second axial location therealong and selectably positioning the endoscope head by selectable extension of the first and second pluralities of selectably radially extendible elements.  
         [0063]     In accordance with a preferred embodiment of the present invention at least one of the first and second pluralities of selectably radially extendible elements includes a plurality of radially extendible elements distributed azimuthally about the endoscope head and the positioning the endoscope head includes selectable extension of individual ones of the plurality of radially extendible elements. Preferably, at least one selectably radially extendable element of the first and second pluralities of selectably radially extendible elements includes an inflatable balloon.  
         [0064]     There is further provided in accordance with still another preferred embodiment of the present invention a method for fluid supply to the interior of a portion of a tubular body portion including providing an element extending along a longitudinal axis and having at least one first selectably extendible tubular body portion sealing element associated therewith at a first axial location therealong and at least one second tubular body portion sealing element associated therewith at a second axial location therealong, extending the at least one first and second tubular body portion sealing elements within a tubular body portion to define a sealed region therebetween and supplying a fluid to the sealed region.  
         [0065]     In accordance with a preferred embodiment of the present invention the supplying a fluid includes supplying a therapeutic fluid. Alternatively, the supplying a fluid includes supplying a contrast enhancing fluid. As a further alternative, the supplying a fluid includes supplying an antiseptic fluid.  
         [0066]     In accordance with another preferred embodiment of the present invention the supplying a fluid includes supplying an acidic solution. Alternatively, the supplying a fluid includes supplying a basic solution.  
         [0067]     There is also provided in accordance with a further preferred embodiment of the present invention an endoscopy method including providing an endoscope tube having an instrument channel and an endoscope tool arranged to travel along the instrument channel to a utilization location forward of the endoscope tube, the endoscope tool being slidably and sealingly located within the instrument channel and selectably pressurizing the instrument channel for providing fluid driven desired positioning of the endoscope tool along the instrument channel.  
         [0068]     There is additionally provided in accordance with a still further preferred embodiment of the present invention an endoscopy method including providing a tube having at least one lumen and an endoscope tool arranged to travel through the at least one lumen, the endoscope tool including a stretchable selectably inflatable anchoring balloon and anchoring the endoscope tool forward of the tube within a tubular body portion by inflating the anchoring balloon into anchoring engagement with an interior wall of the tubular body portion.  
         [0069]     There is also provided in accordance with another preferred embodiment of the present invention an endoscopy method including providing a tube having at least one lumen and an endoscope tool arranged to travel through the at least one lumen, the endoscope tool being selectably bendable forwardly of the tube and selectably bending the endoscope tool forwardly of the tube.  
         [0070]     In accordance with a preferred embodiment of the present invention the endoscope tool includes a stretchable selectably inflatable anchoring balloon and the method also includes anchoring the endoscope tool forward of the tube within a tubular body portion by inflating the anchoring balloon into anchoring engagement with an interior wall of the tubular body portion. Preferably, the endoscopy method also includes sliding the tube forwardly along the endoscope tool, thereby employing the endoscope tool as a guide.  
         [0071]     In accordance with another preferred embodiment of the present invention the endoscopy method also includes, prior to sliding the tube forwardly, the step of tensioning the endoscope tool. Preferably, the endoscopy method also includes the steps of sequentially repeating at least two of the anchoring, tensioning and sliding steps.  
         [0072]     In accordance with yet another preferred embodiment of the present invention the tube includes an endoscope tube. Preferably, the at least one lumen includes an instrument channel.  
         [0073]     There is also provided in accordance with a still further preferred embodiment of the present invention an endoscopy method including providing an endoscope tube having a first stretchable selectably inflatable anchoring balloon adjacent a forward end thereof and an endoscope tool having a second stretchable selectably inflatable anchoring balloon adjacent a forward end thereof and positioning the endoscope tool at a utilization location forward of the endoscope tube.  
         [0074]     In accordance with a preferred embodiment of the present invention the endoscopy method also includes prior to the positioning, inflating the first selectably inflatable anchoring balloon on the endoscope tube within a tubular body portion for anchoring the endoscope tube to an inner wall of the tubular body portion, subsequent to the positioning, inflating the second selectably inflatable anchoring balloon on the tool forward of the endoscope tube within the tubular body portion for anchoring the endoscope tool to the inner wall of the tubular body portion, thereafter, deflating the first selectably inflatable anchoring balloon and advancing the endoscope tube over the endoscope tool by employing the endoscope tool as a guide.  
         [0075]     In accordance with another preferred embodiment of the present invention the endoscopy method also includes bending the endoscope tool when it is forward of the endoscope tube and prior to inflating the second selectably inflatable anchoring balloon. Preferably, the endoscopy method also includes the step of sequentially repeating at least two of the inflating, positioning, deflating and advancing steps.  
         [0076]     In accordance with yet another preferred embodiment of the present invention the endoscopy method also includes the step of sequentially repeating at least two of the inflating, positioning, bending, deflating and advancing steps. Preferably, the positioning of the endoscope tool includes passing the endoscope tool through an instrument channel of the endoscope tube.  
         [0077]     There is further provided in accordance with another preferred embodiment of the present invention an endoscopy method including providing a locomotive endoscope including a locomotive endoscope head and an endoscope body, providing locomotion of the locomotive endoscope head through a tubular body portion, anchoring the locomotive endoscope head at a desired location in the tubular body portion and displacing an endoscopy tool along the endoscope body to a desired tool operation location.  
         [0078]     In accordance with a preferred embodiment of the present invention the endoscopy method also includes tensioning the endoscope body following the anchoring of the locomotive endoscope head and prior to the displacing the endoscopy tool. Preferably, the endoscopy method also includes, prior to the anchoring, the step of detecting the desired location in the tubular body portion by use of at least one light source and at least one imaging sensor associated with the locomotive endoscope head.  
         [0079]     In accordance with another preferred embodiment of the present invention the endoscopy method also includes, prior to the displacing the endoscopy tool, the step of detecting the desired tool operation location in the tubular body portion by use of at least one light source and at least one imaging sensor associated with the locomotive endoscope head. Preferably, the displacing the endoscopy tool includes sliding an overtube associated with the endoscopy tool over the endoscope body.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0080]     The present invention will be understood and appreciated more fully from the following detailed description, taken in conjunction with the drawings in which:  
         [0081]      FIG. 1  is a simplified pictorial illustration of an endoscopy system constructed and operative in accordance with a preferred embodiment of the present invention;  
         [0082]      FIGS. 2 and 3  are respective simplified exploded and assembled view illustrations of a locomotive endoscope head constructed and operative in accordance with a preferred embodiment of the present invention;  
         [0083]      FIGS. 4A, 4B  and  4 C are simplified sectional illustrations taken along respective lines IVA-IVA, IVB-IVB and IVC-IVC in  FIG. 3 ;  
         [0084]      FIGS. 5A, 5B ,  5 C,  5 D,  5 E,  5 F and  5 G are simplified sectional illustrations, taken along lines IVB-IVB in  FIG. 3  of the locomotive endoscope head of  FIGS. 2-4C  at various stages of forward motion through an intestine;  
         [0085]      FIGS. 6A, 6B ,  6 C,  6 D,  6 E,  6 F and  6 G are simplified sectional illustrations, taken along lines IVB-IVB in  FIG. 3  of the locomotive endoscope head of  FIGS. 2-4C  at various stages of rearward motion through an intestine;  
         [0086]      FIGS. 7A, 7B  and  7 C are side view illustrations of selectable tilting orientation of the locomotive endoscope head of  FIGS. 1-6G  within a body passageway.  
         [0087]      FIGS. 8A, 8B  and  8 C are simplified rearward facing views corresponding to  FIGS. 7A, 7B  and  7 C, taken along planes VIIIA-VIIIA, VIIIB-VIIIB and VIIIC-VIIIC in  FIGS. 7A, 7B  and  7 C respectively;  
         [0088]      FIGS. 9A, 9B  and  9 C are simplified forward facing views corresponding to  FIGS. 7A, 7B  and  7 C, taken along planes IXA-IXA, IXB-IXB and IXC-IXC in  FIGS. 7A, 7B  and  7 C respectively;  
         [0089]      FIGS. 10A and 10B  are side view illustrations of selectable parallel orientation of the locomotive endoscope head of  FIGS. 1-6G  within a body passageway;  
         [0090]      FIGS. 11A and 11B  are simplified rearward facing views corresponding to  FIGS. 10A and 10B  taken along planes XIA-XIA and XIB-XIB in  FIGS. 10A and 10B  respectively;  
         [0091]      FIGS. 12A and 12B  are simplified forward facing views corresponding to  FIGS. 10A and 10B  taken along planes XIIA-XIIA and XIIB-XIIB in  FIGS. 10A and 10B  respectively;  
         [0092]      FIG. 13  is a simplified pictorial illustration of an accessory which is adapted to travel through the instrument channel in the locomotive endoscope head of any of  FIGS. 1-12B ;  
         [0093]      FIG. 14  is a simplified partially block diagram, partially schematic illustration of part of the endoscopy system of  FIGS. 1-13 , constructed and operative in accordance with a preferred embodiment of the present invention;  
         [0094]      FIG. 15  is a simplified pictorial illustration of the locomotive endoscope head of  FIGS. 1-12B  in an intestine fluid treatment mode of operation;  
         [0095]      FIGS. 16A, 16B  and  16 C, are simplified pictorial illustrations of the locomotive endoscope head of  FIGS. 1-12B  in a guide wire mode of operation.  
         [0096]      FIG. 17  is a simplified pictorial illustration of an endoscopy system constructed and operative in accordance with another preferred embodiment of the present invention;  
         [0097]      FIGS. 18, 19A  and  19 B are respective simplified pictorial and sectional view illustrations of an accessory constructed and operative in accordance with a preferred embodiment of the present invention;  
         [0098]      FIGS. 20A, 20B ,  20 C,  20 D,  20 E,  20 F,  20 G,  20 H and  20 I are simplified illustrations of various functionalities which may be provided by the system of  FIG. 17 .  
         [0099]      FIG. 21  is a simplified pictorial illustration of an endoscopy system constructed and operative in accordance with another preferred embodiment of the present invention;  
         [0100]      FIGS. 22, 23A  and  23 B are respective simplified pictorial and sectional view illustrations of an accessory constructed and operative in accordance with a preferred embodiment of the present invention; and  
         [0101]      FIGS. 24A, 24B ,  24 C,  24 D,  24 E,  24 F,  24 G,  24 H,  24 I,  24 J,  24 K and  24 L are simplified illustrations of various functionalities which may be provided by the system of  FIG. 21 .  
     
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS  
       [0102]     Reference is now made to  FIG. 1 , which is a simplified pictorial illustration of an endoscopy system constructed and operative in accordance with a preferred embodiment of the present invention.  
         [0103]     The terms “endoscope” and “endoscopy” are used throughout in a manner somewhat broader than their customary meaning and refer to apparatus and methods which operate within body cavities, passageways and the like, such as, for example, the small intestine, the large intestine, arteries and veins. Although these terms normally refer to visual inspection, as used herein they are not limited to applications which employ visual inspection and refer as well to apparatus, systems and methods which need not necessarily involve visual inspection.  
         [0104]     As seen in  FIG. 1 , a conventional endoscopy system  100 , such as a console including a CV-160 video system center, a CLC-160 light source, an OEV-203 video monitor, and an OFP flushing pump, all commercially available from Olympus America Inc. of 2 Corporate Center Drive, Melville, N.Y. 11747, USA, is being employed. A locomotive endoscope head  102 , constructed and operative in accordance with a preferred embodiment of the present invention is located within the large intestine of a patient and is coupled to system  100  by a multi-lumen tube  104 , also constructed and operative in accordance with a preferred embodiment of the present invention, which interfaces with locomotive head controller  106  and an operator control  108 , both of which are also constructed and operative in accordance with a preferred embodiment of the present invention.  
         [0105]     Reference is now made to  FIGS. 2 and 3 , which are respective simplified exploded and assembled view illustrations of a locomotive endoscope head constructed and operative in accordance with a preferred embodiment of the present invention and to  FIGS. 4A, 4B  and  4 C, which are simplified sectional illustrations taken along respective lines IVA-IVA, IVB-IVB and IVC-IVC in  FIG. 3 .  
         [0106]     As seen in  FIGS. 2-4C , a multi-lumen tube  104 , having a central passageway  202 , defining an instrument channel useful inter alia for tool insertion, inssuflation and suction, and a plurality of peripheral lumens  204 , typically ten in number, is seated in a suitably configured recess  206  formed in a housing portion  208 . Housing portion  208 , which is generally symmetric about a longitudinal axis  210 , includes a relatively wider rear portion  212 , which defines recess  206  and a relatively narrower main portion  214 .  
         [0107]     Rear portion  212  is formed with three pairs  220  of axial slits which extend to the rear of rear portion  212  and which are mutually separated along the circumference of rear portion  212  by 120 degrees. Intermediate each pair  220  of axial slits, there is provided an inflation passageway  222 , each of which communicates with a corresponding inflation passageway  224  formed in multi-lumen tube  202 , which in turn communicates with a respective one of three rear balloon inflation lumens  226 , which are included in the nine multiple peripheral lumens  204 . Rear balloon inflation lumens  226  are sealed forwardly of inflation passageways  224  by seals  228 .  
         [0108]     Main portion  214  is formed with three axial slots  230  which extend to the rear of rear portion  212  and which are mutually separated along the circumference of rear portion  212 .  
         [0109]     A slidable forward balloon support  238  is slidably mounted onto main portion  214  of housing portion  208 . Forward balloon support  238  is formed with three pairs  240  of axial slits which extend to the rear of forward balloon support  238  and which are mutually separated along the circumference of forward balloon support  238  by 120 degrees. Intermediate each pair  240  of axial slits, there is provided an inflation passageway  242 , each of which communicates with a corresponding inflation passageway  244  which extends rearwardly into slidable sealing engagement with a respective one of three forward balloon inflation lumens  246 , which are included in the nine multiple peripheral lumens  204 . It is appreciated that inflation passageways  244  are typically relatively rigid and sealingly slide within suitably configured low friction liners  248  which are inserted into forward balloon inflation lumens  246  at the forward end of the multi-lumen tube  104 .  
         [0110]     A pair of piston rods  250  are fixed to or integrally formed with forward balloon support  238  and extend inwardly and rearwardly thereof into slidable sealing engagement with a respective one of two forward balloon support axial positioning lumens  252 , which are included in the ten multiple peripheral lumens  204 . It is appreciated that piston rods  250  are typically relatively rigid and sealingly slide within suitably configured low friction liners  254  which are inserted into forward balloon support axial positioning lumens  252  at the forward end of the multi-lumen tube  104 .  
         [0111]     The relatively rigid inflation passageways  244  and the piston rods  250  are preferably located within axial slots  230 .  
         [0112]     A front housing portion  260  is fixedly mounted onto a forward end  262  of the main portion  214  of the housing portion  208 . Front housing portion includes a cap portion  264  which is fixed to or integrally formed with a cylindrical portion  266  which extends through a central bore  268  of slidable forward balloon support  238 . A rearward end of cylindrical portion  266  is seated in a recess  270  and against a shoulder  272  defined in central passageway  202  of multi-lumen tube  104 . An interior bore  274  of cylindrical portion  266  defines a continuation of the instrument channel defined by central passageway  202 .  
         [0113]     At a forward end of cap portion  264  there are preferably provided a light emitting diode  280  and one or more imaging sensors  282 . Electrical current is supplied to the light emitting diode  280  and imaging data is received from sensors  282  via an optical fiber and electrical conductor bundle  284  which extends from the forward end of cap portion  264 , through a peripheral lumen  286  in multi-lumen tube  104  to locomotive head controller  106  ( FIG. 1 ).  
         [0114]     An additional peripheral lumen  290  is provided in multi-lumen tube  104  for fluid communication with the interior of the intestine via slots  230  in housing portion  208 . Liquids or pressurized gas may be introduced or drained through this lumen.  
         [0115]     An inflatable balloon cylinder  300  is mounted onto rear portion  212  of housing portion  208 . As seen clearly in  FIG. 2 , inflatable balloon cylinder  300  has a uniform cross section which includes three pairs  320  of axial walls which extend along the longitudinal length thereof and engage corresponding axial slits  220  which extend to the rear of rear portion  212 . Each pair  320  of axial walls is joined by a circumferential wall portion  322 . Axial walls pairs  320  are mutually separated along the circumference of inflatable balloon cylinder  300  by 120 degrees.  
         [0116]     Intermediate pairs  320  of axial walls there are defined three inflatable balloon portions  324 , each of which separately communicates with a separate inflation passageway  222 . Balloon portions  324  are sealed with respect to the rear portion  212  at forward and rearward ends thereof and at slits  220  by adhesive or in any other suitable manner to define three separate and independently controllably inflatable and deflatable balloon portions, distributed about the periphery of rear portion  212 . It is appreciated that any suitable smaller or larger number of separate and independently controllably inflatable and deflatable balloon portions may be alternatively employed, although at least three such separate and independently controllably inflatable and deflatable balloon portions are preferred.  
         [0117]     An inflatable balloon cylinder  350  is mounted onto forward balloon support  238 . As seen clearly in  FIG. 2 , inflatable balloon cylinder  350  has a uniform cross section which includes three pairs  370  of axial walls which extend along the longitudinal length thereof and engage corresponding axial slits  240  which extend to the rear of forward balloon support  238 . Each pair  370  of axial walls is joined by a circumferential wall portion  372 . Axial walls pairs  370  are mutually separated along the circumference of inflatable balloon cylinder  350  by 120 degrees.  
         [0118]     Intermediate pairs  370  of axial walls there are defined three inflatable balloon portions  374 , each of which separately communicates with a separate inflation passageway  242 . Balloon portions  374  are sealed with respect to the forward balloon support  238  at forward and rearward ends thereof and at slits  240  by adhesive or in any other suitable manner to define three separate and independently controllably inflatable and deflatable balloon portions, distributed about the periphery of forward balloon support  238 . It is appreciated that any suitable smaller or larger number of separate and independently controllably inflatable and deflatable balloon portions may be alternatively employed, although at least three such separate and independently controllably inflatable and deflatable balloon portions which are 60 degrees out of phase with the balloon portions on rear portion  212  are preferred.  
         [0119]     It is appreciated that in accordance with a preferred embodiment of the present invention the balloon cylinders  300  and  350  are generally stretchable, and can be stretched to accommodate expansion to a radius up to about 5-20 times greater than the radius of cylinders  300  and  350 , when uninflated. Preferably inflation of balloon cylinders  300  and  350  may be achieved using relatively low pressure, such as in the range of 10-50 milibars.  
         [0120]     It is appreciated that in accordance with a preferred embodiment of the present invention useful for in vivo inspection of a generally tubular body portion having a variable cross-sectional diameter, the expansion diameter range of balloon cylinders  300  and  350  is larger than the maximum cross-sectional diameter of the generally tubular body portion, thereby ensuring engagement of expanded balloon cylinders  300  and  350  with the interior surface of the generally tubular body portion, and anchoring of the locomotive endoscope head  102  thereto. Preferably, balloon cylinders  300  and  350  are relatively soft, highly compliant balloons, operative to at least partially conform to the shape of the interior surface of the generally tubular body portion when in engagement therewith.  
         [0121]     It is appreciated that balloon cylinders  300  and  350  may be formed of well-known stretchable materials such as latex, flexible silicon, or highly flexible nylon. Alternatively, balloon cylinders  300  and  350  may be formed of polyurethane which is less stretchable and conforming than latex, flexible silicon, or highly flexible nylon. Preferably, balloon cylinders  300  and  350  have diameters which are sufficient to ensure tight anchoring at any part of the generally tubular body portion.  
         [0122]     Reference is now made to  FIGS. 5A, 5B ,  5 C,  5 D,  5 E,  5 F and  5 G, which are simplified sectional illustrations, taken along lines IVB-IVB in  FIG. 3 , of the locomotive endoscope head of  FIGS. 2-4C  at various stages of forward motion through an intestine. As seen in  FIGS. 5A-5G , locomotion of the locomotive endoscope head  102  of  FIGS. 2-4C  is achieved by a combination of sequential inflations and deflations of balloons, here respectively designated by reference numerals  500  and  502  mounted onto the housing portion  208  and the forward balloon support  238 , combined with relative axial displacement of forward balloon support  238  vis-à-vis housing portion  208 . It is appreciated that each of balloons  500  and  502  preferably includes multiple separate and independently controllably inflatable and deflatable balloon portions as described hereinabove.  
         [0123]     Turning to  FIG. 5A , it is seen that balloon  500  is inflated, thus engaging an inner wall of an intestine and fixing the position of the housing portion  208  relative thereto. In this orientation, the forward balloon support  238  is shown in a rearward axial orientation, adjacent rear portion  212 . Considering  FIG. 5B , it is seen that forward balloon support  238  has moved axially forward relative to housing portion  208 , while the housing portion  208  remains axially fixed relative to the intestine.  
         [0124]     Turning to  FIG. 5C , it is seen that with the forward balloon support  238  in its  FIG. 5B  axial orientation, the balloon  502  is inflated, thus engaging the inner wall of the intestine and fixing the position of the forward balloon support  238  relative thereto.  
         [0125]     Thereafter, as shown in  FIG. 5D , balloon  500  is deflated.  
         [0126]     Turning to  FIG. 5E , it is seen that subsequent to deflation of balloon  500 , the forward balloon support  238  is moved axially rearward relative to housing portion  208 , while the forward balloon support  238  remains axially fixed relative to the intestine. This results in axial forward movement of the housing portion  208  and thus of the locomotive endoscope head  102 .  
         [0127]     Turning to  FIG. 5F , it is seen that with the forward balloon support  238  in its  FIG. 5E  axial orientation, the balloon  500  is inflated, thus engaging the inner wall of the intestine and fixing the position of the housing portion  208  relative thereto. Thereafter, as shown in  FIG. 5G , balloon  502  is deflated.  
         [0128]     It is thus appreciated that in this manner, forward displacement of the locomotive endoscope head  102  is effected.  
         [0129]     Reference is now made to  FIGS. 6A, 6B ,  6 C,  6 D,  6 E,  6 F and  6 G, which are simplified sectional illustrations, taken along lines IVB-IVB in  FIG. 3 , of the locomotive endoscope head of  FIGS. 2-4C  at various stages of rearward motion through an intestine. As seen in  FIGS. 6A-6G , rearward locomotion of the locomotive endoscope head  102  of  FIGS. 2-4C  is achieved by a combination of sequential inflations and deflations of balloons, here too respectively designated by reference numerals  500  and  502  mounted onto the housing portion  208  and the forward balloon support  238 , combined with relative axial displacement of forward balloon support  238  vis-a-vis housing portion  208 . It is appreciated that each of balloons  500  and  502  preferably includes multiple separate and independently controllably inflatable and deflatable balloon portions as described hereinabove.  
         [0130]     Turning to  FIG. 6A , it is seen that balloon  500  is inflated, thus engaging an inner wall of an intestine and fixing the position of the housing portion  208  relative thereto. In this orientation, the forward balloon support  238  is shown in a rearward axial orientation, adjacent rear portion  212 . Considering  FIG. 6B , it is seen that with the forward balloon support  238  in its  FIG. 6A  axial orientation, the balloon  502  is inflated, thus engaging the inner wall of the intestine and fixing the position of the forward balloon support  238  relative thereto. Thereafter, as shown in  FIG. 6C , balloon  500  is deflated.  
         [0131]     Turning to  FIG. 6D , it is seen that forward balloon support  238  has moved axially forward relative to housing portion  208 , while the forward balloon support  238  remains axially fixed relative to the intestine.  
         [0132]     Turning to  FIG. 6E , it is seen that with the forward balloon support  238  in its  FIG. 6D  axial orientation, the balloon  500  is inflated, thus engaging the inner wall of the intestine and fixing the position of the housing portion  208  relative thereto. Thereafter, as shown in  FIG. 6F , balloon  502  is deflated.  
         [0133]     Turning now to  FIG. 6G , it is seen that forward balloon support  238  has moved axially rearward relative to housing portion  208 , while the housing portion  208  remains axially fixed relative to the intestine.  
         [0134]     It is thus appreciated that in this manner, rearward displacement of the locomotive endoscope head  102  is effected. Alternatively, both balloons  500  and  502  may be deflated and the locomotive endoscope head  102  may be pulled out of the intestine by pulling on the multi-lumen tube  104 .  
         [0135]     Reference is now made to  FIGS. 7A-9C , which illustrate various different orientations of the locomotive endoscope head  102  of  FIGS. 2-4C  which may be realized by suitable selectable inflation of individual balloon lobes of balloons  500  and  502 . These illustrations are examples of non-parallel, tilted orientations achieved by any suitable non-identical inflation of balloon lobes of balloon  500  as well as a corresponding non-identical inflation of the balloon lobes  502  in an opposite sense, taking into account the phase difference in the rotational orientations of the balloon lobes of balloons  500  and  502 .  
         [0136]     Turning to  FIGS. 7A, 8A  and  9 A, there are seen illustrations of a downward facing, selectable tilting orientation of the locomotive endoscope head of  FIGS. 1-6G  within a body passageway. This orientation is achieved by relatively low inflation of one balloon lobe of balloon  500 , here designated by reference numeral  510  and relatively high inflation of balloon lobes of balloon  500  designated by reference numerals  512  and  514 , at the same time as there is provided relatively low inflation of one balloon lobe of balloon  502 , here designated by reference numeral  520  and relatively high inflation of balloon lobes of balloon  502  designated by reference numerals  522  and  524 . It is noted that in the orientation of  FIGS. 7A-7C , balloon lobes  510  and  520  are respectively at the top and the bottom of locomotive endoscope head  102 , in the sense of  FIGS. 7A-7C .  
         [0137]     Turning to  FIGS. 7B, 8B  and  9 B, there are seen illustrations of a second, parallel orientation of the locomotive endoscope head of  FIGS. 1-6G  within a body passageway. This orientation is achieved by generally identical inflation of balloon lobes  510 ,  512  and  514  of balloon  500  as well as identical inflation of balloon lobes  520 ,  522  and  524  of balloon  502 .  
         [0138]     Turning to  FIGS. 7C, 8C  and  9 C, there are seen illustrations of a third, upward facing, selectable tilting orientation of the locomotive endoscope head of  FIGS. 1-6G  within a body passageway. This orientation is achieved by relatively high inflation of balloon lobe  510  of balloon  500  and relatively low inflation of balloon lobes  512  and  514  of balloon  500 , at the same time as there is provided relatively high inflation of balloon lobe  520  of balloon  502  and relatively low inflation of balloon lobes  522  and  524  of balloon  502 .  
         [0139]     Reference is now made to  FIGS. 10A and 10B , which are side view illustrations of selectable parallel, off-center orientation of the locomotive endoscope head of  FIGS. 1-6G  within a body passageway, to  FIGS. 11A and 11B , which are rearward facing views corresponding to  FIGS. 10A and 10B  taken along planes XIA-XIA and XIB-XIB in  FIGS. 10A and 10B  respectively and to  FIGS. 12A and 12B , which are forward facing views corresponding to  FIGS. 10A and 10B  taken along planes XIIA-XIIA and XIIB-XIIB in  FIGS. 10A and 10B  respectively. These illustrations are examples of parallel orientations achieved by any suitable non-identical inflation of balloon lobes  510 ,  512  and  514  of balloon  500  as well as a corresponding non-identical inflation of balloon lobes  520 ,  522  and  524  of balloon  502 , taking into account the phase difference in the rotational orientations of the balloon lobes of balloons  500  and  502 .  
         [0140]     Turning to  FIGS. 10A, 11A  and  12 A, there are seen illustrations of a first, off center parallel orientation of the locomotive endoscope head of  FIGS. 1-6G  within a body passageway. This orientation is achieved by relatively low inflation of balloon lobe  510  and relatively high inflation of balloon lobes  512  and  514  of balloon  500  as well as a corresponding relatively high inflation of balloon lobe  520  and relatively low inflation of balloon lobes  522  and  524  of balloon  502 , which takes into account the phase difference in the rotational orientations of the balloon lobes of balloons  500  and  502 .  
         [0141]     Turning to  FIGS. 10B, 11B  and  12 B, there are seen illustrations of a second, off center parallel orientation of the locomotive endoscope head of  FIGS. 1-6G  within a body passageway. This orientation is achieved by relatively high inflation of balloon lobe  510  and relatively low inflation of balloon lobes  512  and  514  of balloon  500  as well as a corresponding relatively low inflation of balloon lobe  520  and relatively high inflation of balloon lobes  522  and  524  of balloon  502 .  
         [0142]     It may be appreciated from a consideration of  FIGS. 7A-12B  that in practice any desired, geometrically permitted, orientation of the locomotive endoscope head  102  may be realized if at least three balloon lobes are provided on both balloons  500  and  502 . This includes, for example up-down and side-to-side tilts and combinations thereof as well as desired up-down and side-to-side off-center parallel orientations and combinations thereof.  
         [0143]     It is appreciated that various desired, geometrically permitted, orientations of the locomotive endoscope head  102  may be realized if at least two balloon lobes are provided on each of balloons  500  and  502 , and in particular if the at least two balloon lobes of balloons  500  and  502  are azimuthally offset.  
         [0144]     It is a particular feature of the present invention that due to the fact that the locomotive endoscope is moved other than by a push mechanism, multi-lumen tube  104  may be substantially more flexible than other endoscope tubes.  
         [0145]     Reference is now made to  FIG. 13 , which is a simplified pictorial illustration of an accessory  600  which is adapted to travel through the instrument channel defined in the central passageway  202  of the multi-lumen tube  104  and in interior bore  274  of cylindrical portion  266  of locomotive endoscope head  102 . The accessory  600  may be selected from among any suitable accessories, such as biopsy forceps, polypectomy snares, foreign body retrieval devices, heat probes and needles, some of which are well known in the art. In accordance with a preferred embodiment of the invention, a piston  602  is associated with the accessory along its body  604  and upstream of its head  606 . The piston  602  is configured for slidable sealed motion along the instrument channel in response to pressure differences upstream and downstream thereof, such as provided by suitable positive or negative pressurization of the instrument channel, which may be carried out for example, by conventional inssuflation and suction functionalities that are provided in conventional endoscope systems.  
         [0146]     Reference is now made to  FIG. 14 , which is a simplified partially block diagram, partially schematic illustration of part of the endoscopy system of  FIGS. 1-13 , constructed and operative in accordance with a preferred embodiment of the present invention.  
         [0147]     As seen in  FIG. 14 , a conventional endoscopy system  100 , such as a console including a CV-160 video system center, a CLC-160 light source, an OEV-203 video monitor, and an OFP flushing pump, all commercially available from Olympus America Inc. of 2 Corporate Center Drive, Melville, N.Y. 11747, USA, is being employed. Conventional endoscopy system  100  includes an inssuflation/suction generator  700  and a liquid supply  702  which communicate via a flow control valve  704  with the instrument channel defined by central passageway  202  of the multi-lumen tube  104  and by interior bore  274  of cylindrical portion  266  of locomotive endoscope head  102 . The conventional endoscopy system  100  also preferably includes an imaging system  710  and an LED controller  712  which communicate via electrical data and power lines preferably embodied in optical fiber and electrical conductor bundle  284  which extend through lumen  286  in multi-lumen tube  104 .  
         [0148]     Operator control  108 , preferably including a joystick  722 , tilt/non-tilt functionality selection switch  724  and a button  725  for governing the direction (forward/backward) and speed of motion, governs the operation of locomotive head controller  106 . In a preferred embodiment of the present invention, as shown, the operator control  108  provides control inputs to locomotive head control circuitry  726 , which operates an air pressure generator  728 , a vacuum generator  730  and a hydraulic positive/negative pressure supply  732 .  
         [0149]     Air pressure generator  728  and vacuum generator  730  are coupled to lumens  226  and  246  for selectable inflation of balloon lobes  510 ,  512 ,  514 ,  520 ,  522  and  524  via suitable manifolds  734  and  736  and via individual flow valves for each of the lumens, the flow valves being designated by reference numerals  740 ,  742 ,  744 ,  746 ,  748  and  750 . Hydraulic positive/negative pressure supply  732  is coupled via a flow valve  752  to lumens  252  for driving piston rods  250 . Additionally a flow valve  754  governs supply of a treatment fluid to lumen  290  from a treatment fluid reservoir  756 . A further fluid valve  758  governs removal of the treatment fluid via lumen  290  from the intestine to a discard fluid location (not shown) which is maintained under vacuum.  
         [0150]     Flow valves  704 ,  740 ,  742 ,  744 ,  746 ,  748 ,  750 ,  752 ,  754  and  758  are controlled by operator control  108  via locomotive head control circuitry  726  to suitably inflate and deflate balloon lobes  510 ,  512 ,  514 ,  520 ,  522  and  524  for providing selected positioning and/or tilt of the locomotive endoscope head  102  within the intestine; to suitably displace forward balloon support  238  for locomotion of the locomotive endoscope head  102  and for selectably supplying treatment fluid to the intestine as described hereinbelow with reference to  FIG. 15 .  
         [0151]     Reference is now made to  FIG. 15 , which is a simplified pictorial illustration of the locomotive endoscope head of  FIGS. 1-12B  in an intestine fluid treatment mode of operation. As seen in  FIG. 15 , tubular body portion sealing elements such as balloon lobes  510 ,  512  and  514  of balloon  500  and balloon lobes  520 ,  522  and  524  of balloon  502  are preferably all inflated, so as to seal the volume of the intestine intermediate balloon lobes  510 ,  512  and  514  and balloon lobes  520 ,  522  and  524  from the remainder of the interior volume of the intestine.  
         [0152]     Once sealing is achieved, a treatment fluid  760  is supplied from treatment fluid reservoir  756  via valve  754 , lumen  290  and slots  230  to the sealed portion of the intestine. Following treatment, the treatment fluid  760  may be suctioned from the sealed portion of the intestine via slots  230 , lumen  290  and valve  758  to a fluid discard location (not shown). Optionally and preferably, treatment fluid  760  includes at least one of a therapeutic fluid, a contrast enhancing fluid, an antiseptic fluid, an acidic solution, a basic solution or any other suitable fluid.  
         [0153]     Reference is now made to  FIGS. 16A-16C , which are simplified pictorial illustrations of the locomotive endoscope head of  FIGS. 1-12B  in a guide wire mode of operation. As seen in  FIG. 16A , balloon lobes  510 ,  512  and  514  of balloon  500  and balloon lobes  520 ,  522  and  524  of balloon  502  are preferably all inflated, so as to anchor the locomotive endoscope head  102  to the intestine. Once anchoring is achieved at a desired location, multi-lumen tube  104  is tensioned, as seen in  FIG. 16B .  
         [0154]     It is appreciated that respective diameter of balloons  500  and  502  are sufficient to ensure tight anchoring at any part of the intestine.  
         [0155]     As seen in  FIG. 16C , an overtube  800  is slid over multi-lumen tube  104 , using it as a guide wire. The overtube  800  preferably includes, at a forward portion  802  thereof, an endoscopy tool  804 . Preferably, endoscopy tool  804  may be a therapeutic, diagnostic or surgical tool, and may be selectably positioned along the multi-lumen tube  104 . In a preferred embodiment of the present invention, endoscopy tool  804  is an ultrasonic transducer. In another preferred embodiment of the present invention, endoscopy tool  804  is an X-ray radiation source/generator.  
         [0156]     Reference is now made to  FIGS. 17-19B , which are respectively a simplified pictorial illustration of an endoscopy system constructed and operative in accordance with another preferred embodiment of the present invention and respective simplified pictorial and sectional view illustrations of an accessory constructed and operative in accordance with a preferred embodiment of the present invention.  
         [0157]     As seen in  FIGS. 17-19B , a conventional endoscopy system  1000 , such as a console including a CV-160 video system center, a CLC-160 light source, an OEV-203 video monitor, and an OFP flushing pump, all commercially available from Olympus America Inc. of 2 Corporate Center Drive, Melville, N.Y. 11747, USA, is being employed. A conventional endoscope  1002 , which forms part of conventional endoscopy system  1000  may be employed, such as a CF-Q160AL video colonoscope which is commercially available from Olympus America Inc. of 2 Corporate Center Drive, Melville, N.Y. 11747, USA.  
         [0158]     An endoscope tool  1010 , constructed and operative in accordance with a preferred embodiment of the present invention extends through the instrument channel  1011  of the conventional endoscope  1002 . Endoscope tool  1010  is characterized in that it includes a multi-lumen tube  1012  which includes at least a first lumen  1014  for inflation and deflation of a balloon  1016  via an inflation aperture  1017 , and a second lumen  1018 . Preferably the second lumen  1018  may accommodate a tensioning or compression wire  1020 . Alternatively or additionally, the second lumen  1018  may have other functionality. As a further alternative, the multi-lumen tube  1012  forming part of the endoscope tool  1010  may include more than two lumens. Preferably, the cross-sectional area of the multi-lumen tube  1012  is sufficiently less than that of the instrument channel  1011 , so as to allow supply of fluid for inssuflation and draining of fluid therethrough.  
         [0159]     It is appreciated that in accordance with a preferred embodiment of the present invention the endoscope tool  1010  and the multi-lumen tube  1012  are generally substantially more flexible than conventional endoscope  1002  and an endoscope tube thereof.  
         [0160]     It is appreciated that in accordance with a preferred embodiment of the present invention the balloon  1016  is generally stretchable, and can be stretched to a diameter about 5-20 times larger than its diameter when not inflated. In a specific embodiment, useful for small intestine endoscopy, the balloon diameter when fully stretched is four centimeters. Preferably, inflation of the balloon  1016  to a diameter less than four centimeters may be achieved using relatively low pressure, such as in the range of 10-50 milibars. In another specific embodiment, useful for large intestine endoscopy, the balloon diameter when fully stretched is seven centimeters. Preferably, inflation of the balloon  1016  to a diameter less than seven centimeters may be achieved using relatively low pressure, such as in the range of 10-50 milibars.  
         [0161]     It is appreciated that in accordance with a preferred embodiment of the present invention useful for in vivo inspection of a generally tubular body portion having a variable cross-sectional diameter, the expansion diameter range of balloon  1016  is larger than the maximum cross-sectional diameter of the generally tubular body portion, thereby ensuring engagement of expanded balloon  1016  with the interior surface of the generally tubular body portion, and anchoring of the endoscope tool  1010  thereto. Preferably, balloon  1016  is a relatively soft, highly compliant balloon, operative to at least partially conform to the shape of the interior surface of the generally tubular body portion when in engagement therewith.  
         [0162]     It is appreciated that balloon  1016  may be formed of well-known stretchable materials such as latex, flexible silicon, or highly flexible nylon. Alternatively, balloon  1016  may be formed of polyurethane, which is less stretchable and conforming than latex, flexible silicon or highly flexible nylon. Preferably, the diameter of balloon  1016  is sufficient to ensure tight anchoring at any part of the generally tubular body portion.  
         [0163]     As seen in  FIGS. 17-19B , the endoscope tool  1010  preferably includes a tool positioning control device  1024  and a balloon inflation/deflation control interface  1026 . It is appreciated that multi-lumen tube  1012  and the entire endoscope tool  1010  may be inserted and removed via a conventional tool port  1030  on a conventional operator control  1032  which forms part of conventional endoscope  1002 .  
         [0164]     Reference is now made to  FIGS. 20A, 20B ,  20 C,  20 D,  20 E,  20 F,  20 G,  20 H and  201 , which are simplified illustrations of the endoscope tool  1010  of  FIGS. 17-19B  in various operative orientations. In the illustrated embodiment, desired directional orientation of the forward end of the endoscope tool  1010  is obtained by suitable axial displacement of the tool through the instrument channel  1011  of the endoscope  1002  combined with suitable tensioning of wire  1020  and with suitable rotational orientation of the endoscope tool  1010  relative to the intestine.  
         [0165]     As seen in  FIG. 20A , endoscope tool  1010  is principally located within the instrument channel  1011  of endoscope  1002 , and has balloon  1016  protruding therefrom, while in a deflated state.  
         [0166]      FIG. 20B  shows the endoscope tool  1010  extending further from the instrument channel  1011 , while  FIG. 20C  shows the endoscope tool  1010  having been rotated by  180  degrees relative to its orientation in  FIG. 20B  by suitable twisting of multi-lumen tube  1012 , as indicated by arrow  1022 .  
         [0167]      FIG. 20D  shows bending of the forward end of the endoscope tool  1010  resulting from tensioning of wire  1020 , when the tool is in its  FIG. 20C  orientation having been pushed forward in a conventional manner.  
         [0168]      FIG. 20E  shows further progress of the endoscope tool  1010  through the intestine resulting from forward pushing of the tool coupled with release the tension on the wire  1020  by operation of tool positioning control device  1024 .  
         [0169]      FIG. 20F  shows inflation of the balloon  1016  by operation of the balloon inflation/deflation control interface  1026 . In accordance with a preferred embodiment of the invention, this inflation anchors the forward end of the endoscope tool  1010  to the intestine at the location of the balloon  1016 .  
         [0170]      FIG. 20G  shows tensioning of the endoscope tool  1010  including the multi-lumen tube  1012  by pulling on the multi-lumen tube  1012 .  
         [0171]      FIG. 20H  shows the endoscope  1002  having been pushed forward along the multi-lumen tube  1012 , using the multi-lumen tube as a sort of guide wire. Endoscope  1002  may be pushed forward in a conventional manner. Thereafter, as shown in  FIG. 19 , the balloon  1016  may be deflated.  
         [0172]     Further forward progress of the endoscope through the intestine, preferably to a position where the forward end of the instrument channel  1011  lies just behind the balloon  1016 , similarly to the orientation shown in  FIG. 20A , may be achieved by repeating some or all of the steps described hereinabove with reference to  FIGS. 20A-20I , as required by the geometries encountered.  
         [0173]     Reference is now made to  FIGS. 21-23B , which are respectively a simplified pictorial illustration of an endoscopy system constructed and operative in accordance with another preferred embodiment of the present invention and respective simplified pictorial and sectional view illustrations of an accessory constructed and operative in accordance with a preferred embodiment of the present invention.  
         [0174]     As seen in  FIGS. 21-23B  a conventional endoscopy system  1300 , such as a console including a CV-160 video system center, a CLC-160 light source, an OEV-203 video monitor, and an OFP flushing pump, all commercially available from Olympus America Inc. of 2 Corporate Center Drive, Melville, N.Y. 11747, USA, is being employed. A conventional endoscope  1302 , which forms part of conventional endoscopy system  1300  may be employed, such as a CF-Q160AL video colonoscope which is commercially available from Olympus America Inc. of 2 Corporate Center Drive, Melville, N.Y. 11747, USA. In accordance with a preferred embodiment of the invention, a peripheral balloon  1304  may be mounted onto endoscope  1302  as shown. Preferably inflation and deflation of peripheral balloon  1304  may be provided by a tube  1306  communicating with the interior thereof.  
         [0175]     An endoscope tool  1310 , constructed and operative in accordance with a preferred embodiment of the present invention extends through the instrument channel  1311  of the conventional endoscope  1302 . Endoscope tool  1310  is characterized in that it includes a multi-lumen tube  1312  which includes at least a first lumen  1314  for inflation and deflation of a balloon  1316  via an inflation aperture  1317 , and a second lumen  1318 . Preferably the second lumen  1318  may accommodate a tensioning or compression wire  1320 . Alternatively or additionally, the second lumen  1318  may have other functionality. As a further alternative, the multi-lumen tube  1312  forming part of the endoscope tool  1310  may include more than two lumens. Preferably, the cross-sectional area of the multi-lumen tube  1312  is sufficiently less than that of the instrument channel  1311 , so as to allow supply of fluid for inssuflation and draining of fluid therethrough.  
         [0176]     It is appreciated that in accordance with a preferred embodiment of the present invention the endoscope tool  1310  and the multi-lumen tube  1312  are generally substantially more flexible than endoscope  1302  and an endoscope tube thereof.  
         [0177]     It is appreciated that in accordance with a preferred embodiment of the present invention the balloon  1316  is generally stretchable, and can be stretched to a diameter about 5-20 times larger than its diameter when not inflated. In a specific embodiment, useful for small intestine endoscopy, the balloon diameter when fully stretched is four centimeters. Preferably, inflation of the balloon  1316  to a diameter less than four centimeters may be achieved using relatively low pressure, such as in the range of 10-50 milibars. In another specific embodiment, useful for large intestine endoscopy, the balloon diameter when fully stretched is seven centimeters. Preferably, inflation of the balloon  1316  to a diameter less than seven centimeters may be achieved using relatively low pressure, such as in the range of 10-50 milibars.  
         [0178]     It is appreciated that in accordance with a preferred embodiment of the present invention useful for in vivo inspection of a generally tubular body portion having a variable cross-sectional diameter, the expansion diameter range of balloon  1316  is larger than the maximum cross-sectional diameter of the generally tubular body portion, thereby ensuring engagement of expanded balloon  1316  with the interior surface of the generally tubular body portion, and anchoring of the endoscope tool  1310  thereto. Preferably, balloon  1316  is a relatively soft, highly compliant balloon, operative to at least partially conform to the shape of the interior surface of the generally tubular body portion when in engagement therewith.  
         [0179]     It is appreciated that balloon  1316  may be formed of well-known stretchable materials such as latex, flexible silicon, or highly flexible nylon. Alternatively, balloon  1316  may be formed of polyurethane, which is less stretchable and conforming than latex, flexible silicon or highly flexible nylon. Preferably, the diameter of balloon  1316  is sufficient to ensure tight anchoring at any part of the generally tubular body portion.  
         [0180]     As seen in  FIGS. 21-23B , the endoscope tool  1310  preferably includes a tool positioning control device  1324  and a balloon inflation/deflation control interface  1326 . Additionally, there is preferably provided a peripheral balloon inflation/deflation control interface  1328 , which communicates with tube  1306  and governs inflation and deflation of peripheral balloon  1304 . It is appreciated that multi-lumen tube  1312  and the entire endoscope tool  1310  may be inserted and removed via a conventional tool port  1330  on a conventional operator control  1332  which forms part of conventional endoscope  1302 .  
         [0181]     Reference is now made to  FIGS. 24A, 24B ,  24 C,  24 D,  24 E,  24 F,  24 G,  24 H,  24 I,  24 J,  24 K and  24 L, which are simplified illustrations of the endoscope tool  1310  of  FIGS. 21-23B  in various operative orientations. In the illustrated embodiment, desired directional orientation of the forward end of the endoscope tool  1310  is obtained by suitable axial displacement of the tool through the instrument channel  1311  of the endoscope  1302  combined with suitable tensioning of wire  1320  and with suitable rotational orientation of the endoscope tool  1310  relative to the intestine.  
         [0182]     As seen in  FIG. 24A , endoscope tool  1310  is principally located within the instrument channel  1311  of endoscope  1302 , and has balloon  1316  protruding therefrom, while in a deflated state. As seen, peripheral balloon  1304  is in a deflated state.  
         [0183]      FIG. 24B  shows endoscope tool  1310  being principally located within the instrument channel  1311  of endoscope  1302 , and has balloon  1316  protruding therefrom, while in a deflated state. As seen, peripheral balloon  1304  is in an inflated state in engagement with an interior wall of the intestine, thereby anchoring the endoscope  1302  thereat.  
         [0184]      FIG. 24C  shows the endoscope tool  1310  extending further from the instrument channel  1311 , while  FIG. 24D  shows the endoscope tool  1310  having been rotated by  180  degrees relative to its orientation in  FIG. 24C , by suitable twisting of multi-lumen tube  1312 , as indicated by arrow  1340 .  
         [0185]      FIG. 24E  shows bending of the forward end of the endoscope tool  1310  resulting from tensioning of wire  1320 , when the tool is in its  FIG. 24D  orientation having been pushed forward in a conventional manner.  
         [0186]      FIG. 24F  shows further progress of the endoscope tool  1310  through the intestine resulting from forward pushing of the tool coupled with release the tension on the wire  1320  by operation of tool positioning control device  1324 .  
         [0187]      FIG. 24G  shows inflation of the balloon  1316  by operation of the balloon inflation/deflation control interface  1326 . In accordance with a preferred embodiment of the invention, this inflation anchors the forward end of the endoscope tool  1310  to the intestine at the location of the balloon  1316 .  
         [0188]      FIG. 24H  shows tensioning of the endoscope tool  1310  including the multi-lumen tube  1312  by pulling on the multi-lumen tube  1312 .  
         [0189]      FIG. 24I  shows deflation of peripheral balloon  1304 .  
         [0190]      FIG. 24J  shows the endoscope  1302  having been pushed forward along the multi-lumen tube  1312 , using the multi-lumen tube as a sort of guide wire. Endoscope  1302  may be pushed forward in a conventional manner.  
         [0191]      FIG. 24K  shows inflation of peripheral balloon  1304  into engagement with an interior wall of the intestine, thereby anchoring the endoscope  1302  thereat.  
         [0192]     Thereafter, as shown in  FIG. 24L , the balloon  1316  may be deflated.  
         [0193]     Further forward progress of the endoscope through the intestine, preferably to a position where the forward end of the instrument channel  1311  lies just behind the balloon  1316 , similarly to the orientation shown in  FIG. 24B , may be achieved by repeating some or all of the steps described hereinabove with reference to  FIGS. 24B-24L , as required by the geometries encountered.  
         [0194]     It will be appreciated by persons skilled in the art that the present invention is not limited to what has been particularly shown and described hereinabove. Rather the scope of the present invention includes both combinations and subcombinations of various features described hereinabove as well as modifications thereof which would occur to persons skilled in the art upon reading the foregoing specification and which are not in the prior art.