Dissecting aneurysm of the anterior cerebral artery requiring surgical treatment--case report.

A 45-year-old male presented with spontaneous dissecting aneurysm in the anterior cerebral artery manifesting as headache persisting for several days and speech disturbance. Neurological and laboratory examinations showed no abnormalities. Magnetic resonance imaging revealed infarction in the right cingulate gyrus. Angiography revealed occlusion of the right A2. Repeat angiography 8 months later showed a saccular aneurysm had developed. The interhemispheric approach exposed the aneurysm at the junction between the right frontopolar artery and the pericallosal artery. The aneurysm was fusiform due to the right A2 dissection. The aneurysm was trapped and resected. One month after the operation, the patient was discharged without neurological deficits. Cases of dissecting aneurysms in the anterior cerebral artery with ischemic onset are usually treated conservatively. Cases requiring surgery include those due to trauma, growing aneurysms, giant aneurysms, and uncontrolled hypertension. Some dissecting aneurysms of the distal anterior cerebral artery require only resection without bypass surgery.