[A variant of persistent trigeminal artery associated with a petroclival meningioma. Case report]

A 52-year-old female was admitted with a chief complaint of progressive gait disturbance over the previous 16 months. Neurological examination revealed impairment of the Vth and VIIIth cranial nerve functions and cerebellar ataxia on the left side. Computed tomography showed a petroclival tumor of 5 x 5 x 4.5 cm. Left carotid angiography disclosed tumor staining fed by branches of the tentorial artery. Also, an anomalous artery branched from the internal carotid artery between the C5 and C6 portions and supplied the region usually fed by the anterior inferior cerebellar artery. The tumor was removed via a combination of transpetrosal-transtentorial and transzygomatic approaches. The anomalous artery was confirmed to course along the Vth cranial nerve, replacing the anterior inferior cerebellar artery. Twenty-seven cases of variant persistent trigeminal artery have been reported in the world literature, including this case. The embryological and clinical features of this anomaly are discussed.