A unique finding of the basilar artery.

Variants of the posterior intracranial circulation are important for surgeon, interventionalists and radiologists. Herein, a unique configuration of the basilar artery is reported. A 54-year-old man with a history of COPD, hypothyroidism, smoking, and hyperlipidemia presented to an outside institution with nausea, confusion, altered mental status, and ataxia. The patient was evaluated for stroke. Imaging revealed rotation of the basilar apex of 180 degrees, fetal configuration of the posterior communicating artery, right posterior cerebral artery filling from the left vertebral artery, and duplication of the left and right superior cerebellar arteries. The patient continued to deteriorate neurologically and MRI revealed multifocal and symmetric signal abnormalities in the brain stem, thalami, basal ganglia, and hippocampi. The differential diagnosis included acute disseminated myeloencephalitis. Despite plasma exchange and steroid therapy, the patient died a few days later. This case report demonstrates a rare variation of the basilar apex.