A case of Joubert's syndrome with extensive cerebral malformations

Joubert's syndrome is a relatively rare, autosomal-recessive syndrome defin ed by vermis hypoplasia, hypotonia, developmental delay and at least one of two additional manifestations: abnormal breathing pattern or abnormal eye movements. Detailed descriptions of the neuropathological findings in this syndrome are scarce. We present a radiological and pathological correlation of a case of Joubert's syndrome in which, apart from the classic vermis ap lasia and some malformations of the brain stem and the spinal cord, extensi ve malformations of the cerebrum were found. The dentate nuclei were broken into islands and showed a few heterotopias within the superior cerebellar pedunculi, the inferior olives were plump and dysplastic, and an almost com plete absence of the pyramidal decussation was found. In the spinal cord, t he dorsal columns were located in a dorsal position within the spinal grey matter. In the cerebrum, absence of the corpus callosum was found. Many nod ular heterotopias of the cerebral cortex and of the basal ganglia, the amyg dala and the diencephalon were observed. The present case is compared to pr evious pathological descriptions of the Joubert syndrome and to other syndr omes with comparable malformations of the posterior fossa.