MR brain investigation in thirty-five children with Leber's congenital amaurosis

There are few literature reports of MR study in children with Leber's congenital amaurosis, a severe early onset autosomal recessive retinal dystrophy. We describe the clinical and neuroradiological findings in 35 patients. Of these, 22 had a normal brain MR scan, four showed mild dilatation of the cortical sulci, two had mild optic-chiasmatic thinning, three showed aspecific white matter changes not involving the primary visual pathway and four had ``molar tooth'' mesencephalic malformation. Our series confirms literature findings of normal signal and morphology of the primary optic pathway. Posterior cranial fossa abnormalities, defined as rhombencephaloschisis, was associated with a clinical picture different from that of the other patients. This abnormality is encountered in different malformations associating cerebellar, ocular and renal abnormalities. MR brain study in children with Leber's congenital amaurosis is recommended not only to assess the visual pathways, but also to analyse the posterior cranial fossa and cerebellum.