Bilateral duplicated middle cerebral arteries.

Bilateral identical duplications of the middle cerebral artery are extremely rare. We report this anatomical variation in a 56-year-old woman. The anatomical variation was identified using magnetic resonance angiography, which was performed to evaluate cerebrovascular disease. Bilaterally, one middle cerebral artery originated from the internal carotid artery bifurcation and the other originated from the internal carotid artery terminal segment. The anatomical variations were incidental findings, and the patient was asymptomatic.