Direct surgery for giant aneurysm exhibiting progressive enlargement after intraaneurysmal balloon embolization

A case of giant intracranial carotid artery aneurysm exhibiting progressive enlargement after incomplete intraaneurysmal balloon embolization is presented. The patient was successfully treated by the trapping and decompression of the aneurysm with a superficial temporal artery-middle cerebral artery anastomosis. The thrombus surrounding the intraluminal balloons was very soft and poorly organized. Either direct surgery with extracranial-intracranial arterial bypass or complete intravascular surgery should be performed for giant aneurysms when direct clipping is impossible.