We review our recent experience with occlusion of the cervical internal carotid artery (ICA) in 15 patients with symptomatic aneurysms of the cavernous segment. All the patients were women and ranged in age from 38 to 74 years. Ten patients sought treatment initially for ophthalmoplegia, 9 for retro-orbital pain, 8 for facial paresthesia, and 3 for loss of vision. Two patients had symptoms of transient ocular or brain ischemia. The diameter of the aneurysm was greater than 3 cm in 10 patients. Ten patients underwent gradual occlusion of the ICA by Selverstone clamp under anticoagulation and monitoring of neurological status. One patient underwent ligation of a severely stenotic ICA under general anesthesia and electroencephalographic monitoring. Four patients underwent trapping of the aneurysm (after attempts at direct obliteration) under electroencephalographic and cerebral blood flow monitoring. Two patients with incompetent circle of Willis collaterals underwent prophylactic superficial temporal artery to middle cerebral artery bypass surgery prior to ICA occlusion. There was no postoperative clinical change in 9 patients. Ophthalmoplegia improved in 2 patients, and facial pain improved in 3. Three patients developed new extraocular muscle palsies within hours of ICA occlusion; these resolved in all patients by 1 week postoperatively. No change in aneurysm size was documented by serial postoperative computed tomographic or magnetic resonance imaging scans. After a follow-up of 5 to 6 years (range, 6 months-9 years), 11 patients have remained neurologically stable. Two patients experienced delayed transient worsening of visual or facial symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)