We present a rare case of a 68-year-old woman who experienced dizziness, nausea, vomiting, and imbalance for 2 months. Imaging studies, including magnetic resonance imaging, magnetic resonance angiography, and digital subtraction angiography, revealed an intrasellar course of the persistent trigeminal artery (PTA) with atherosclerotic changes. Additionally, hypoplasia of the basilar artery and left vertebral artery was observed. The anatomically rare intrasellar PTA, combined with atherosclerosis and vertebrobasilar hypoplasia, likely contributed to compromised posterior circulation and the patient’s symptoms. This case highlights the importance of considering vascular anomalies and the associated pathological changes in patients with otherwise unexplained posterior circulation symptoms.