Endoscopic vessel harvesting system components

A vessel dissector useable in conjunction with an endoscope, the vessel dissector comprising:

• an elongated cannula including a lumen therein configured to receive an endoscope;
• a blunt dissecting tip provided on a distal end of the elongated cannula that permits an operator of the vessel dissector to dissect tissue while viewing internal body structures via an objective lens of the endoscope;
• a vessel severing tool extending through at least a portion of the elongated cannula, wherein the vessel severing tool is moveable to translate longitudinally relative to the elongated cannula, and wherein the vessel severing tool comprises an electrode-carrying member that is moveable to translate circumferentially within a bow-shaped slot extending through an outer surface of the vessel dissector, wherein the bow-shaped slot comprises an inner radius and an outer radius defining an arc, wherein the outer radius is greater than the inner radius so that the bow-shaped slot provides an opening of uniform width through which the electrode-carrying member is controllable to extend and retract, and wherein an arcuate cross section of the electrode-carrying member matches curvature and width of the arc of the bow-shaped slot so movement of the electrode-carrying member translating circumferentially in the bow-shaped slot is constrained to move along a central arc of the bow-shaped slot.