Parent Artery Occlusion for Symptomatic Large Internal Carotid Artery Aneurysm with Primitive Trigeminal Artery Variant: A Case Report

OBJECTIVE: To report a case of symptomatic large cerebral aneurysm of the internal carotid artery (ICA), associated with a primitive trigeminal artery variant (PTAv), which was treated with a balloon occlusion test (BOT) to evaluate ischemic tolerance. CASE PRESENTATION: A 79-year-old woman was diagnosed with a symptomatic large cerebral aneurysm of the ICA bifurcating the PTAv due to diplopia. After confirming the ischemic tolerance of the perfusion area and PTAv by BOT, we performed ICA parent artery occlusion with selective embolization of the PTAv. Postoperative MRI showed no ischemic lesion and the diplopia was resolved. CONCLUSION: ICA parent artery occlusion with PTAv selective embolization after evaluation by BOT is useful in the treatment of large aneurysms.