Patient with Pelizaeus-Merzbacher disease showing abnormal white matter on brain MRI

Brain MRI of a patient with Pelizaeus-Merzbacher disease. On T2-weighted MRI (left image), there is diffuse white matter involvement with hyperintense (bright) signal throughout, whereas normal white matter should be hypointense (dark). On T1-weighted MRI (right image), the white matter is mildly hypointense (dark), whereas normal white matter should be hyperintense (bright) on T1.