MRI appearances of metachromatic leukodystrophy

Background. The leukodystrophies constitute a wide spectrum of cerebral disorders of varying etiology. The imaging appearances on CT and MRI are recognizable as abnormalities of white matter; however, it may be impossible to arrive at the correct diagnosis based on imaging studies alone. Patients and methods. Three patients of varying age and clinical symptomatology diagnosed with metachromatic leukodystrophy (MLD) had remarkably similar MRI appearances. A “tigroid” or “leopard-skin” appearance was demonstrated within deep white matter in each case. Results. All of the patients had biochemical confirmation of MLD. Conclusion. Although the “tigroid” pattern previously was considered to be pathognomonic of Pelizaeus-Merzbacher disease, the diagnosis of MLD must now be considered when these MRI appearances are encountered.