ORIGINAL RESEARCH Hypomyelination and Congenital Cataract: Neuroimaging Features of a Novel Inherited

BACKGROUND AND PURPOSE: Hypomyelination and congenital cataract (HCC) is an autosomal reces-sive white matter disease caused by deficiency of hyccin, a membrane protein implicated in both central and peripheral myelination. We aimed to describe the neuroimaging features of this novel entity. MATERIALS AND METHODS: A systematic analysis of patients with unclassified leukoencephalopathies admitted to our institutions revealed 10 children with congenital cataract, slowly progressive neuro-logic impairment, and diffuse white matter abnormalities on neuroimaging. Psychomotor developmen-tal delay was evident after the first year of life. Peripheral neuropathy was demonstrated by neuro-physiologic studies in 9 children. The available neuroimaging studies were retrospectively reviewed. RESULTS: In all patients, neuroimaging revealed diffuse involvement of the supratentorial white matter associated with preservation of both cortical and deep gray matter structures. Supratentorial white matter hypomyelination was detected in all patients; 7 patients also had evidence of variably extensive areas of increased white matter water content. Deep cerebellar white matter hypomyelination was found in 6 patients. Older patients had evidence of white matter bulk loss and gliosis. Proton MR spectroscopy showed variable findings, depending on the stage of the disease. Sural nerve biops