From May 1993 to June 1995 47 patients underwent endovascular treatment of 45 aneurysms using fibered coils in the first six cases and Guglielmi detachable coils in the remaining 42. 26 cases involved acute treatment after subarachnoid hemorrhage; of these 14 were in poor clinical condition and had been considered inoperable. Six aneurysms were located in the posterior and 42 in the anterior circulation. Embolisation was complete in 30 cases out of 48 (62%), subtotal (>70%) and partial (<70%) in 12 (25.5%) and 2 (4%). Four patients (8.5%) could not be treated for technical reasons. Perforation of the sac occurred during treatment in two cases (4%): in both embolisation of the aneurysm was achieved and bleeding stopped without clinical deterioration. Despite heparin administration neurological deficits occurred from probable thromboembolism in eight cases, four (8%) promptly recovered fully while two (4%) had mild deficits and two (4%) remained critical and died a few days later.