The "over the core wire" technique for detachable coil retrieval.

SUMMARY: We report four cases of malpositioned detachable coil retrieval. In all cases, the malpositioned coils were retrieved without additional neurological deficits. The stretched core wire was grasped with a fixed-loop snare (Gooseneck microsnare), and the detachable coil was retrieved using an over the core wire technique with a hydrophilic microcatheter.