Leukoencephalopathy, megalencephalic, with subcortical cysts, 2B

A neurodegenerative disorder characterized by infantile-onset of macrocephaly and mildly delayed motor development associated with white-matter abnormalities on brain magnetic resonance imaging. The phenotype is milder that MLC2A, with better preserved cerebellar white matter and no subcortical cysts outside the temporal region. On follow-up, patients show normal or almost normal motor function. Some patients have normal intelligence, whereas others have a significant cognitive deficiency.