CEREBRAL ANEURYSM ASSOCIATED WITH PERSISTENT PRIMITIVE OLFACTORY ARTERY ANEURYSM

Persistent primitive olfactory artery is a rare vascular anomaly but h as a clinical importance because of its high association with cerebral aneurysm. We describe a patient with bilateral persistent primitive o lfactory arteries associated with an unruptured saccular aneurysm on t he left persistent primitive olfactory artery. Seven reported cases wi th this anomalous artery including ours are reviewed and classified in to two variants. This anomalous artery arises from the terminal portio n of the internal carotid artery and courses anteromedially along the ipsilateral olfactory tract and makes a hair-pin curve posterior to th e olfactory bulb, becoming the distal anterior cerebral artery (varian t 1) or the ethmoidal artery (variant 2). Out of 7 reported cases, 4 c ases are associated with saccular aneurysms. The aneurysm in variant 1 is located on the hair-pin curve at which an apparent arterial branch is sometimes absent. Two patients suffer from anosmia. Persistent pri mitive olfactory artery should be kept in mind because of its high ass ociation with intracranial saccular aneurysms and unique clinical pres entation.