We aimed to assess and to demonstrate the efficiency of a new mechanical system in the endovascular treatment of berry intracranial aneurysms. From September 1999 to October 2000, 38 patients with 40 aneurysms experienced selective embolization using Detach Coils (DCS((R)) - Cook). They were 12 men and 26 women, aged 26 to 77 years, mean age 53.4. The clinical status of patients was graded by Hunt and Hess scale: Stage 0: 8 - stage I: 3 - Stage II: 11 - Stage III: 11 - Stage IV: 2 - Stage V: 3. The localization of aneurysms was as follows: internal carotid artery: 11; sylvian artery: 10; anterior communicating artery: 5; anterior cerebral artery A1-A2: 5; intra-cavernous carotid artery: 1; basilar trunk: 5; PICA: 2; posterior cerebral artery: 1. The size of the aneurysms ranged from 2 to 40 mm. For embolization of aneurysms, we utilized 242 coils (mean number 6.05). The shape and size of coils varied as follows: longest J 6.25 - shortest J 4-3 - longest S 10-20 - shortest S 2-2. The mean time of procedure was 43 minutes (max 180 minutes - min 7 minutes). We did not have any technical complications during the . procedure and no immediate rebleeding occurred. Initial follow-up of the patients showed angiographic full occlusion. Detach Coils appear to be a very precise, reliable and rapid system, with high stability during coil detachment (in very small or very giant aneurysms) in the embolization of intracranial aneurysms, with an interesting aspect concerning the low cost of this new mechanical device.