Early cerebellar degeneration in twins with infantile neuroaxonal dystrophy.

Dizygotic twin girls with typical infantile neuroaxonal dystrophy (INAD) were studied at age 19 months with computed tomography and magnetic resonance imaging (MRI). Both methods showed distinct atrophy confined to the cerebellum and MRI revealed diffuse signal abnormality of the cerebellar parenchyma. This neuro-imaging evidence for selective early involvement of the cerebellum is consistent with both the typical presenting symptoms and the gross pathological findings in the disorder. Neuroimaging may aid in differentiation of INAD from other neurodegenerative disorders with onset in late infancy, providing impetus for diagnostic biopsy and early genetic counseling.