A new delivery system for placement of Gianturco coils has been devised that permits retrieval of the coil if malposition occurs. The delivery system itself consists of a very fine coaxial cannula that will cut the monofilament once the coil is properly placed. It has been successfully used on three patients in whom a total of 48 coils were employed to occlude great vein of Galen aneurysms. The system is applicable for routine coil embolization but has particular application in treating high-flow vascular lesions (arteriovenous fistulas or malformations).