Infratentorial arteriovenous malformation associated with persistent primitive trigeminal artery--case report.

A 58-year-old male presented with a rare association of an infratentorial arteriovenous malformation (AVM) and ipsilateral persistent primitive trigeminal artery (PPTA) manifesting as sudden onset of headache and vomiting. Computed tomography revealed subarachnoid hemorrhage, and digital subtraction angiography demonstrated an infratentorial AVM mainly fed by the left superior cerebellar artery via the left PPTA. The patient refused radical treatment for the AVM, and was conservatively treated. The adjacent AVM may have been important in the preservation of the PPTA, as blood flow into the infratentorial AVM via the PPTA and the hemodynamic stress to the PPTA could have disturbed the spontaneous closure of the PPTA.