Rupture of aneurysms following balloon embolization.

Three cases of complex aneurysms are presented in which balloon embolization therapy was associated with subsequent aneurysmal rupture, causing subarachnoid hemorrhage in two cases and a carotid-cavernous fistula in one. Two of these patients were treated directly by balloon embolization following surgical exploration. The third patient developed the fistula during postembolization volume expansion and heparinization.