Abstract
We report a male patient with a ruptured persistent primitive trigeminal artery variant aneurysm that resulted in a fistula with the cavernous sinus. He presented with left conjunctival hyperemia and exophthalmos. Cerebral angiography revealed a left direct carotid-cavernous fistula; however, a balloon occlusion test determined that the source was actually a ruptured aneurysm located on the trunk of a persistent primitive trigeminal artery. Endovascular trapping of the persistent primitive trigeminal artery was performed, which resulted in fistula occlusion and symptom resolution.