Anomalous origin of the anterior inferior cerebellar arteries from the internal carotid artery.

Two cases of the anterior inferior cerebellar arteries originating from the cavernous and precavernous segments of the internal carotid artery are reported. In one case the course of the anomalous artery was confirmed by autopsy. This anomalous artery is considered to be a variant of persistent primitive trigeminal artery. The clinical significance is disussed briefly.