Giant intracranial aneurysms: diagnosis, management, and outcome.

The diagnosis, management, and outcome of a consecutive series of 25 patients with giant intracranial aneurysms are presented. Symptoms and signs directly or indirectly attributable to the intracranial mass effect accounted for presentation in 16 (64%) patients of whom seven had no focal neurological deficits. Nine patients (36%) presented after subarachnoid hemorrhage. Subarachnoid hemorrhage was frequently associated with intraventricular or intracerebral hemorrhage, a poor clinical grading at admission, and a high mortality (67%). Computed tomographic features of the giant aneurysms were usually characteristic; however, angiography was particularly useful in those in close proximity to the skull base. Nineteen patients had a surgical procedure directly or indirectly aimed at obliteration, isolation, or reinforcement of the giant aneurysm. Successful surgical obliteration or occlusion was obtained in 12 (63%) patients, while seven (37%) had only reinforcement or exploration of the aneurysm. The mortality associated with definitive surgical treatment was 5.6%, and major morbidity occurred in 17%. The good long-term outcome in 75% of the patients after occlusion of the giant aneurysm contrasted with the continuing mortality (43%) and morbidity (43%) in those patients in whom surgical obliteration of the aneurysm was not attained. Although advances in microsurgical instrumentation, anesthetic techniques, and innovative revascularization procedures have facilitated the surgical management of giant aneurysms, significant improvement in the high overall mortality associated with these aneurysms (36% in this series) will probably only be attained by diagnosis of giant intracranial aneurysms before they bleed.