Endoscopic vessel harvesting system components

Abstract

Components for an endoscopic vessel harvesting system suitable for harvesting target vessels such as the saphenous vein or radial artery for cardiac artery bypass graft surgery. The main components of such systems include a vessel dissector and a vessel harvester, both of which work in conjunction with a separately provided endoscope. The vessel dissector is an elongated cannula having a blunt tip for separating layers of facial around vessels. The tip may be movable, and is typically transparent to permit viewing forward of the tip using the endoscope. Internal features of the tip may reduce glare back to the endoscope. Several devices improve visibility through the tip by reducing interference from tissue or fluid on the tip. The vessel harvester also has an elongated cannula for receiving the endoscope. Several tools within the harvester permit manipulation, severing, and sealing of vessels forward of the distal end. The tool for manipulating vessels may have a low-profile for increased visibility of operation, and may be coupled to the cannula with a damping mechanism to reduce the possibility of avulsion of the vessels. Various vessel cutting and sealing devices are provided that may accommodate various sizes of vessels and improve cutting and sealing efficacy.

1 - 16 . (canceled) 
     
     
         17 . A vessel dissector that is used in conjunction with an endoscope, comprising:
 an elongated cannula including a lumen therein for receiving the endoscope; and   a transparent blunt tip provided on a distal end of the elongated cannula that permits an operator of the dissector to dissect tissue while viewing internal body structures via an objective lens of the endoscope; and   a wiper for clearing tissue from the exterior of the transparent blunt tip.   
     
     
         18 . The vessel dissector of  claim 17 , wherein the wiper is arranged on the elongated cannula to pivot about an axis to alternately contact and disengage from the transparent blunt tip, and a mechanism for rotating the blunt tip. 
     
     
         19 . The vessel dissector of  claim 17 , wherein the wiper is arranged on the elongated cannula to contact the blunt tip and swivel about the axis of the device. 
     
     
         20 . The vessel dissector of  claim 17 , wherein the wiper is an O-ring wiper fitted over the blunt tip and connected to an actuation rod that displaces the O-ring wiper longitudinally to wipe over the blunt tip. 
     
     
         21 . The vessel dissector of  claim 17 , wherein the wiper is arranged on the elongated cannula to contact the blunt tip and has an energized cutting electrode thereon to remove tissue via ablation. 
     
     
         22 . The vessel dissector of  claim 17 , further including a handle disposed at a proximal end of the elongated cannula and a thumb lever thereon connected to an actuating rod for displacing the wiper relative to the transparent blunt tip and clearing tissue therefrom. 
     
     
         23 - 62 . (canceled) 
     
     
         63 . A tissue dissector, comprising:
 an elongated cannula including a distal end and a lumen for receiving an endoscope;   a tissue dissection tip configured for dissecting tissue, wherein the tissue dissection tip comprises a conical one piece structure tapering to a blunt end configured for tissue dissection, and is coupled to the distal end of the elongated cannula;   an articulation interface between the elongated cannula and the tissue dissection tip, the articulation interface comprising an articulation body; and   a first control member comprising a first elongated body extending through the elongated cannula and connected to the tissue dissection tip, wherein the first control member engages and applies a force to the tissue dissection tip and is configured to tilt the tissue dissection tip relative to a longitudinal axis of the elongated cannula so as to directionally orient and facilitate maneuverability of the tissue dissection tip;   wherein the articulation body is configured to change an angle of the tissue dissection tip relative to the longitudinal axis of the elongated cannula and wherein the articulation interface exerts a force sufficient to revert the tissue dissection tip back to axial alignment with the longitudinal axis of the elongated cannula when the force applied by the first control member is released; and   wherein the first control member occupies a space in the elongated cannula, and the tissue dissection tip is transparent.   
     
     
         64 . The tissue dissector of  claim 63 , further comprising a second control member comprising an elongated body extending through the elongated cannula and connected to the tissue dissection tip, wherein the second control member applies a force to the tissue dissection tip for tilting the transparent structure relative to the elongated cannula. 
     
     
         65 . The tissue dissector of  claim 63 , wherein the articulation interface comprises an accordion-like flexible sleeve that is coupled between the tissue dissection tip and the elongated cannula. 
     
     
         66 . The tissue dissector of  claim 63 , wherein the articulation interface comprises a spherical bearing surface coupled between the tissue dissection tip and the elongated cannula. 
     
     
         67 . The tissue dissector of  claim 63 , further comprising an opening disposed to deliver insufflation gas, wherein the opening is located at the tissue dissection tip. 
     
     
         68 . The tissue dissector of  claim 67 , further comprising a barrier covering the opening. 
     
     
         69 . The tissue dissector of  claim 63 , further comprising an opening for delivering gas, wherein the opening is located at a side of the elongated cannula. 
     
     
         70 . The tissue dissector of  claim 69 , further comprising a barrier covering the opening. 
     
     
         71 . The tissue dissector of  claim 63 , wherein the first control member is configured to tilt the tissue dissection tip about an axis that is perpendicular to the longitudinal axis of the elongated cannula. 
     
     
         72 . The tissue dissector of  claim 63 , wherein the endoscope and the first control member occupy different respective space in the elongated cannula. 
     
     
         73 . The tissue dissector of  claim 63 , wherein the first control member is spaced apart from the endoscope and comprises a steering wire. 
     
     
         74 . The tissue dissector of  claim 63 , wherein the tissue dissection tip has an inner surface that is aligned with a center of the lumen, the inner surface oriented to prevent light from being reflected towards the center of the lumen. 
     
     
         75 . The tissue dissector of  claim 63 , wherein the first control member extends through the tissue dissection tip and is connected to a surface of the tissue dissection tip under tension and wherein the first control member applies a pull force with respect to the tissue dissection tip for tilting the tissue dissection tip relative to the longitudinal axis of the elongated cannula. 
     
     
         76 . A tissue dissector, comprising:
 an elongated cannula including a distal end and a lumen for receiving an endoscope;   a tissue dissection tip configured for dissecting tissue, wherein the tissue dissection tip comprises a conical one piece structure tapering to a blunt end configured for tissue dissection, and is coupled to the distal end of the elongated cannula;   an articulation interface between the elongated cannula and the tissue dissection tip, the articulation interface comprising an articulation body;   a first control member comprising a first elongated body extending through the elongated cannula and connected to the tissue dissection tip, wherein the first control member applies a force to the tissue dissection tip and is configured to tilt the tissue dissection tip relative to a longitudinal axis of the elongated cannula so as to directionally orient and facilitate maneuverability of the tissue dissection tip; and   a second control member comprising an elongated body extending through the elongated cannula and connected to the tissue dissection tip, wherein the second control member applies a force to the tissue dissection tip and is configured to tilt the tissue dissection tip relative to the longitudinal axis of the elongated cannula so as to directionally orient and facilitate maneuverability of the tissue dissection tip;   wherein the articulation body is configured to change an angle of the tissue dissection tip relative to the longitudinal axis of the elongated cannula; and   wherein the first control member and the second control member each occupies a space in the elongated cannula.