Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is a rare genetic disorder that affects the brain, spinal cord, and nervous system. There are no direct synonyms for this condition, but it may be described as a leukodystrophy, which refers to disorders that affect the white matter of the brain. Additionally, MLC may be referred to as a cystic leukoencephalopathy due to the presence of cysts in the subcortical region of the brain. Other leukodystrophies may have similar symptoms, such as Canavan disease, which also affects the white matter of the brain and spinal cord. However, each condition is unique in its specific presentation and underlying genetic mutations.