Globoid cell leukodystrophy: Distinguishing early-onset from late-onset disease using a brain MR imaging scoring method

BACKGROUND AND PURPOSE: Our purpose aas to determine the characteristic MR features of early-onset (before age 2 years) versus Irate-onset (after age 2 years) globoid cell leukodystrophy (GLD); METHODS: Thirty-four brain MR images in 22 patients with GLD were reviewed. A severity score (0 to 32), based on a point system derived from the locat ion and extent of disease and the presence of focal and/or global atrophy, was calculated for each examination. RESULTS: Of the 22 patients, three were asymptomatic and 19 were symptomati c. Ten patients had early-onset disease, whereas nine had late-onset diseas e. MR changes of all patients showed abnormalities. In the early-onset grou p (n = 10; mean maximum MR score, 8.1; range, 3-18), 90% had pyramidal trac t involvement, 80% had cerebellar white matter involvement, 70% had deep gr ay matter involvement, and 40% had posterior corpus callosal involvement, 5 0% had parietooccipital white matter involvement, and 40% had cerebral atro phy. Serial MR imaging in four of these patients revealed progressive disea se. In the late-onset group (n = 9; mean maximum MR score, 5.6; range, 4-10 ), 100% had pyramidal tract involvement, 100% had parietooccipital white ma tter involvement, 89% had posterior corpus callosal involvement, and none h ad cerebellar white matter involvement, deep gray matter involvement, or ce rebral atrophy. Serial MR imaging in one patient with late-onset GLD did no t reveal any change, a spectrum of findings was observed in the three patie nts who were asymptomatic. CONCLUSION: Cerebellar white matter and deep gray matter involvement are pr esent only in early-onset GLD. Pyramidal tract involvement is a characteris tic finding in both early- and late-onset GLD. This scoring method for brai n MR observations will assist in the objective assessment of the impact of hematopoietic stem cell transplantation in patients with GLD.