[Persistent carotid-superior cerebellar artery anastomosis presenting with cerebellar ischemic attack: a case of persistent trigeminal artery variant].

A rare case of persistent primitive trigeminal artery variant (PTAV) with cerebellar ischemia is reported. A 23-year-old male complained of sudden dizziness and nausea after playing valley ball. CT scan and MRI on admission revealed no abnormal findings. Left carotid angiography demonstrated a PTAV anastomoting precavernous portion of left internal carotid artery to the left superior cerebellar artery. The 37 cases reported in literature were reviewed to characterise PTAV. Ninety-seven% of the cases arising from precavernous portion of internal carotid artery, and terminated in anterior inferior cerebellar artery in 73%, posterior inferior cerebellar artery in 13.5% and superior cerebellar artery in 13.5%. Approximately 22.2% of patients with PTAV have cerebral aneurysms. The hypotension or mechanical compression of PTAV on playing valley ball with poor vascular supply to the part of cerebellum possibly caused cerebellar ischemia in this case.