Focal cerebellar infarction as an initial sign of mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes.

Mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS) is a type of mitochondrial disorder and stroke-like lesions are observed prominently in the brain magnetic resonance imaging. Those stroke-like lesions of MELAS patients are usually located in the posterior quadrants and do not correspond to typical vascular territories. This case illustrates that focal cerebellar infarction can be the sole initial sign of MELAS.