Abstract: A wire loop (46) is carried at the distal end of a plunger (44 or 120) which, in turn, is telescoped inside a tubular chassis (40, 42). The proximate end of the plunger (44 or 120) projects from the tubular chassis (40, 42) and is connected to the end of a looped spring handle (60 or 60′) by means of which the plunger (44 or 120) can be reciprocated. At the distal end, a nose cone (52) is fitted in the tubular chassis (40, 42) and carries a guide conduit or tip (56) through which the wire loop (46) can be projected or retracted by corresponding movement of the plunger (40 or 120). The wire loop (46) is preformed to a desired shape and curvature and is formed of a material having memory characteristics such that it will return to the predetermined, precurved shape when it is allowed to relax by projection from the guide tip (56).