Primitive trigeminal artery associated with cavernous aneurysm: case report.

A case of unruptured aneurysm at the junction of the cavernous segment of the right internal carotid artery and the primitive trigeminal artery (PTA) is presented. The posterior circulation was not dependent on PTA, thus the PTA was of an adult type in this case. This patient was successfully treated by external carotid artery-anterior temporal artery long vein graft bypass, internal carotid artery ligation at neck, and PTA clipping through the right subtemporal approach. A follow-up angiography showed thrombotic occlusion of the aneurysm. In review of the literature, there are 27 cases reported of PTA aneurysm; among them only 11 cases, including ours, treated surgically. The surgical treatment plan for PTA aneurysm, according to the review of literature is discussed.