Rupture of Aneurysms during and after Embolization with Guglielmi Detachable Coils.

Between March, 1997 and June, 2000, 104 aneurysms, including 75 ruptured and 29 unruptured aneurysms, were treated with Guglielmi detachable coils by 120 embolizations in our institution. Intraprocedual perforation occurred in four cases, representing 3.3% of the embolizations. Subsequently, two cases deteriorated, and the other two cases recovered completely without any deficit. Aneurysmal perforations mostly occurred in acutely ruptured aneurysms, small aneurysms less than 4 mm, anterior communicating artery aneurysms, or first coil delivery. Rebleedings in the acute period of subarachnoid hemorrhage occurred in four cases of partial occlusion due to aneurysmal morphology, such as a wide neck or an irregular shape. Rebleedings in the chronic period occurred in two cases, one of which rebled two months after partial occlusion, and the other of which rebled 27 months after nearly total occlusion. No subarachnoid hemorrhages documented from previously unruptured aneurysms occurred after embolizations. Insufficient embolization for ruptured aneurysms cannot prevent rebleeding, and partially occluded aneurysms and recurring aneurysms in the follow-up period require immediate re-treatment.