Disposable sheath for a miniature endoscope

Abstract

An endoscopic has an fiber optic waveguide that transmits an image from a distal end to a proximal end, the waveguide having an outer diameter of less than 3 mm. A lens system is positioned at the distal end of the fiber optic waveguide. An imaging device is optically coupled to the proximal end of fiber optic waveguide. A disposable sheath extends about the fiber optic waveguide to provide a sterile barrier, and in a preferred embodiment the sheath includes an illumination channel. In a preferred embodiment, the lens system has a first lens element, a second lens element and an aperture stop.

1 . A disposable fiber optic sheath for illuminating a region within a body comprising:
 a medication delivery cannula;   a tubular sheath having a diameter of less than 2 mm and a concentric array of illumination optical fibers within the tubular sheath, the concentric array of illumination optical fibers surrounding an inner tube having a tubular cavity such that a proximal opening of the tubular cavity can receive an endoscope tube, the tubular sheath being positioned within the medication delivery cannula during an imaging procedure;   a sealed image transmitting element at the distal end of the sheath that transmits an image into the tubular cavity; and   a base at a proximal end of the tubular sheath such that the tubular sheath can detachably connect to an endoscope handle, the base including a sheath mounting mechanism couplable to a handle mounting mechanism and a light interface within the sheath mounting mechanism configured to optically couple the concentric array of illumination optical fibers to a light source upon connecting the base to the endoscope handle such that a light source within the handle is optically coupled to the illumination optical fibers through the light interface, the base having a receiving chamber that extends from the proximal opening of the tubular cavity.   
     
     
         2 . The fiber optic sheath of  claim 1  further comprising a sterile barrier attached to the base. 
     
     
         3 . The fiber optic sheath of  claim 2  wherein the sterile barrier comprises a drape adapted to extend over an endo scope handle. 
     
     
         4 . The fiber optic sheath of  claim 1  wherein the sealed image transmitting element comprises a window. 
     
     
         5 . The fiber optic sheath of  claim 1  wherein an annular channel extends between an outer tube and the inner tube. 
     
     
         6 . The fiber optic sheath of  claim 5  wherein the optical fibers fill the annular channel. 
     
     
         7 . The fiber optic sheath of  claim 1  further comprising an endoscope tube having an elongated fiber optic imaging tube. 
     
     
         8 . The fiber optic sheath of  claim 1  wherein the optical fibers at a distal end of the sheath are not protected and exposed to the body. 
     
     
         9 . The fiber optic sheath of  claim 1  further comprising a fluid delivery channel for delivering medication to a region of interest in a body lumen or cavity. 
     
     
         10 . A kit including the fiber optic sheath of  claim 1  and further comprising a trocar insertable into the cannula during insertion of the cannula. 
     
     
         11 . The fiber optic sheath of  claim 1  wherein the sheath mounting mechanism attaches to a handle mounting mechanism on the endoscope handle. 
     
     
         12 . The fiber optic sheath of  claim 5  wherein the inner tube extends proximally further than the outer tube. 
     
     
         13 . The fiber optic sheath of  claim 1  wherein a proximal end of the illumination optical fibers comprise the light interface within the base. 
     
     
         14 . The fiber optic sheath of  claim 1  wherein the receiving chamber is sized to receive a projection of an endoscopy body. 
     
     
         15 . The fiber optic sheath of  claim 14  wherein the receiving chamber is within the base. 
     
     
         16 . The fiber optic sheath of  claim 15  wherein the receiving chamber is proximal to the tubular cavity within the inner tube. 
     
     
         17 . The fiber optic sheath of  claim 1  wherein the light interface optically couples the concentric array of illumination optical fibers to an optical fiber bundle within an endoscope handle at a handle interface. 
     
     
         18 . The fiber optic sheath of  claim 1  wherein the illumination optical fibers are connected to an illumination pigtail. 
     
     
         19 . The fiber optic sheath of  claim 1  wherein the cannula has a shaft and a luer for delivery of medication. 
     
     
         20 . The fiber optic sheath of  claim 1  wherein the sealed image transmitting element is cemented to the inner tube. 
     
     
         21 . The fiber optic sheath of  claim 1  wherein the light interface is adapted to connect to an external light source in an endoscope handle. 
     
     
         22 . A disposable fiber optic sheath for illuminating a region within a mammalian body comprising:
 a medication delivery cannula;   a tubular sheath having a diameter of less than 2 mm and an inner tube, the tubular sheath being positioned within the cannula;   an array of optical fibers within the tubular sheath and surrounding the inner tube, a distal end of the array of optical fibers comprising a concentric illumination surface area at a distal end of the tubular sheath;   a sealing element at the distal end of the tubular sheath to provide a tubular cavity with an opening at a proximal end of the tubular sheath; and   a base mounted at the proximal end of the tubular sheath, the base including a sheath mounting mechanism to detachably connect the base to a handle mounting mechanism of an endoscope handle, the sheath mounting mechanism further including a light interface within the sheath mounting mechanism to optically couple the array of optical fibers to a light source upon connecting the base to the endoscope handle.   
     
     
         23 . The fiber optic sheath of  claim 22  wherein the optical fibers comprise an optical fiber bundle with the light interface at a proximal end. 
     
     
         24 . The fiber optic sheath of  claim 22  wherein the tubular sheath comprises a rigid tube having a circular opening at the proximal end to receive an endoscope image collection tube. 
     
     
         25 . The fiber optic sheath of  claim 22  wherein the sealing element comprises a window that seals an airspace within the inner tube. 
     
     
         26 . The fiber optic sheath of  claim 22  wherein the sheath mounting mechanism attaches to a handle mounting mechanism on the endoscope handle. 
     
     
         27 . The fiber optic sheath of  claim 26  wherein the tubular cavity receives an endoscope imaging tube having a first lens element, a second lens element and an aperture stop optically coupled to a plurality of imaging optical fibers mounted within the endoscope imaging tube. 
     
     
         28 . The fiber optic sheath of  claim 22  further comprising a light source coupled to an illumination source that is positioned in a control unit. 
     
     
         29 . A kit including the fiber optic sheath of  claim 22  wherein the cannula comprises a fluid port. 
     
     
         30 . The fiber optic sheath of  claim 25  wherein the window is cemented to the inner tube to form a sealed distal end of the tubular cavity. 
     
     
         31 . The fiber optic sheath of  claim 22  wherein an annular channel extends between an outer tube and the inner tube. 
     
     
         32 . The fiber optic sheath of  claim 31  wherein the optical fibers fill the annular channel. 
     
     
         33 . The fiber optic sheath of  claim 22  further comprising a receiving chamber. 
     
     
         34 . The fiber optic sheath of  claim 22  wherein the region within the mammalian body comprises an orthopedic region, the cannula having a cannula base and a tube such that the cannula is adapted to cut tissue for insertion to visualize a surgical site of the orthopedic region.