Moyamoya syndrome secondary to MELAS syndrome in a child: A case report and literature revue.

Mitochondrial myopathy with lactic acidosis and stroke-like episodes is a rare mitochondrial disorder, most often revealed by symptoms and signs that typically include mitochondrial myopathy, encephalopathy with stroke-like episodes, seizures and/or dementia, and lactic acidosis. Imaging findings, although diverse, usually present characteristic features that help differentiate these disorders from vascular syndromes. We present a case of a 2-year and 4-month-old girl with recurrent ischemic strokes associated with nonterritorial cortico-subcortical foci on brain imaging, along with stenosis of the terminal portion of the internal carotid arteries associated with a neovascular network. An elevated serum lactate level was found in the biological assessment. This article provides an overview of the various neuroimaging modalities available and the advent of new imaging techniques used in these disorders. It highlights the importance of considering a diagnosis of hereditary mitochondrial disorder in the presence of recurrent atypical stroke-like episodes when neuroimaging is inconsistent with ischemic infarction and reports an exceptional association with Moyamoya syndrome.