The neuroradiological evaluation of Canavan’s disease in a 38 month-old girl is reported from the Alfred I. duPont Institute, Wilmington, DE and Children’s Hospital, Philadelphia, PA. A female child of Ashkenazic Jewish heritage presented at age 5 months with psychomotor retardation and macrocephaly. At age 7 months cerebral brain biopsy confirmed a suspected diagnosis of Canavan’s disease. Over the last 30 months she developed severe spastic quadriparesis, optic atrophy and dysphagia which was treated by gastrostomy at age 27 months. CT showed diffuse symmetrical low attenuation values of the subcortical and deep cerebral white matter. MRI demonstrated symmetrical diffuse low signal density on T1-weighted images and high signal intensity on T2-weighted images. Magnetic resonance spectroscopy showed elevated levels of N-acetylaspartic acid in the occipital lobe. The in vivo measurement of N-acetylaspartic acid in the brain by magnetic resonance spectroscopy offered an additional non-invasive diagnostic test for Canavan’s disease. 
COMMENT. Canavan’s disease or spongy degeneration of the brain in infancy is a rare autosomal recessive leukodystrophy most prevalent among Ashkenazi Jews and Saudi Arabians. Matalon and co-workers have demonstrated an excessive amount of acetylaspartic acid in urine, blood, CSF and a deficiency of aspartoacylase in cultured skin fibroblasts and brain tissue in children with Canavan’s disease . The diagnosis may now be confirmed by magnetic resonance imaging followed by localized 1H magnetic resonance spectroscopy.