Abstract: The wire loop of a surgical snare is constructed so as to include a weakened or frangible region. When it is desired to open the loop so as to move it from its entrapped position on a polyp, an additional force is exerted on the loop to draw it further into the sheath. This causes the frangible region to break, thereby opening the loop and permitting the wire to slide free of the polyp. In accordance with an alternate embodiment, the wire loop is constructed so as to fold back on itself, with the folded back end being captured by a retaining element inside the sheath. When the loop becomes entrapped on a polyp, it is extended out of the sheath somewhat further than during normal use, at which point the captured end of the loop is released, opening the loop and permitting its removal from within the patient.

Abstract: The wire loop of a surgical snare is constructed so as to include a weakened or frangible region. When it is desired to open the loop so as to move it from its entrapped position on a polyp, an additional force is exerted on the loop to draw it further into the sheath. This causes the frangible region to break, thereby opening the loop and permitting the wire to slide free of the polyp. In accordance with an alternate embodiment, the wire loop is constructed so as to fold back on itself, with the folded back end being captured by a retaining element inside the sheath. When the loop becomes entrapped on a polyp, it is extended out of the sheath somewhat further than during normal use, at which point the captured end of the loop is released, opening the loop and permitting its removal from within the patient.

Abstract: A scalpel is provided with a blade guard which is mounted for movement between a blade-guarded position and a blade-exposed position and an actuating mechanism for the blade guard is positioned in such a way that the fingers of the surgeon automatically engage the mechanism when the scalpel is held in its normal position of use. The actuating mechanism is coupled to the blade guard through a linkage assembly which causes the blade guard to move over a substantially greater distance than the distance which the surgeon's fingers move in operating the actuating mechanism. In a preferred embodiment, the blade guard slides over a linear path, the actuating mechanism comprises a tongue-like structure integral with the scalpel, and the linkage assembly comprises a plurality of pivotally interconnected lever arms. One of the lever arms is positioned so as to be captured in a detent mechanism when the blade guard is fully retracted to its blade-exposed position.

Abstract: A scalpel is provided with a blade guard which is mounted for movement between a blade-guarded position and a blade-exposed position and an actuating mechanism for the blade guard is positioned in such a way that the fingers of the surgeon automatically engage the mechanism when the scalpel is held in its normal position of use. The actuating mechanism is coupled to the blade guard through a linkage assembly which causes the blade guard to move over a substantially greater distance than the distance which the surgeon's fingers move in operating the actuating mechanism. In a preferred embodiment, the blade guard slides over a linear path, the actuating mechanism comprises a tongue-like structure integral with the scalpel, and the linkage assembly comprises a plurality of pivotally interconnected lever arms. One of the lever arms is positioned so as to be captured in a detent mechanism when the blade guard is fully retracted to its blade-exposed position.