Serial angiography and endovascular treatment of dissecting aneurysms of the anterior cerebral and vertebral arteries. Case report.

This 47-year-old man was admitted to the hospital with disturbance of consciousness due to subarachnoid hemorrhage caused by a ruptured dissecting aneurysm of the left anterior cerebral artery (ACA). Conservative treatment resulted in improvement in the patient's consciousness; however, repeated rupture occurred during the chronic stage. Endovascular coil embolization of the parent artery was successful. Serial angiography demonstrated all stages in the development of the aneurysm. Follow-up angiography demonstrated an incidental dissecting aneurysm of the right vertebral artery. This aneurysm was also treated by endovascular embolization. No new neurological deficit appeared during or after the treatment. Multiple dissecting aneurysms are rare, especially those involving both supra- and infratentorial regions. A ruptured dissecting aneurysm of the ACA is also an uncommon vascular disorder. This case shows that rebleeding may occur, even during the chronic stage, and thus appropriate treatment for the prevention of subsequent bleeding is essential. Incidental dissecting aneurysms can be treated using the endovascular technique, but further study is necessary.