Twig-like MCA: A rare cause of intracranial bleeding.

Twig-like or unfused middle cerebral artery (MCA) is a rare congenital vascular anomaly defined by the absence of the M1 segment. It can be found incidentally or can be revealed by cerebral ischemia or hemorrhage. Although rare, neuroradiologists should be familiar with such findings in order to differentiate them from differential diagnoses such as Moyamoya disease and steno-occlusive disorders of the MCA. We report a case of a twig-like MCA revealed by intracranial bleeding in an 84-year-old woman.