A series of 54 traumatic carotid-cavernous fistulas has been treated with detachable balloon catheters. The balloon was introduced through one of three different approaches: the endarterial route; the venous route through the jugular vein, the inferior petrosal sinus, and the cavernous sinus; or surgical exposure of the cavernous sinus; with occlusion of the fistula by a detachable balloon directly positioned in the cavernous sinus. Full follow-up review demonstrated that the carotid blood flow was preserved in 59% of cases. The most frequent complication was a transient oculomotor nerve palsy, which occurred in 20% of cases. In three cases where both the fistula and the carotid artery were originally occluded by the balloon, the superior portion of the fistula was later found not to be completely occluded, and these patients had intracranial ligation of the supraclinoid portion of the carotid artery. Three patients had hemiparesis, transient in two cases and permanent in the other. The results show that the fistula was totally occluded in 53 cases; in the one exception the patient became asymptomatic but had a minimal angiographic leak.