A 2 yearold boy with optic atrophy and

A 2 -year-old boy with optic atrophy and an unexpected neuroimaging finding Teaching Neuro. Images Neurology Resident & Fellow Section © 2015 American Academy of Neurology

Vignette • A 2 -year-old Brazilian boy presented with delayed motor skills and language impairment since birth. • Family history disclosed consanguineous parentes. • Examination showed global muscular hypotonia, optic atrophy and oculomotor apraxia. © 2015 American Academy of Neurology Pinto WBVR et al.

Imaging A © 2015 American Academy of Neurology B Pinto WBVR et al.

Imaging C © 2015 American Academy of Neurology D Pinto WBVR et al.

Macrocerebellum as a diagnostic hint • Laboratory tests revealed deficient activity of lysosomal alpha-L-iduronidase in peripheral blood leukocytes and increased urinary excretion of glycosaminoglycan. • Final diagnosis: Mucopolysaccharidosis type I (Hurler disease). © 2015 American Academy of Neurology Pinto WBVR et al.

Macrocerebellum as a diagnostic hint • Macrocerebellum is a rare condition characterized by an abnormally large cerebellum with preservation of the overall shape 1. • It has been described in some conditions such as Sotos Syndrome, Costello Syndrome, Williams Syndrome, Alexander Disease, Fucosidosis and Lhermitte-Duclos disease 1 and can rarely be present in mucopolysaccharidosis 2. © 2015 American Academy of Neurology Pinto WBVR et al.