A CLINICAL AND NEURORADIOLOGICAL STUDY OF X-LINKED HYDROCEPHALUS IN JAPAN

To clarify the clinicopathological features of X-linked hydrocephalus, the authors studied 30 affected males from 15 families. In utero ultr asonography, performed al 21 to 40 weeks of gestation, revealed 18 fet uses with hydrocephalus. Computerized tomography (CT) revealed bilater al enlargement of the lateral ventricle with preponderant dilation of the posterior hem. In five patients with complete magnetic resonance ( MR) imaging data, the most specific finding was localized atrophy of t he anterior vermian lobe. Other MR imaging findings included a large m assa intermedia, flat corpora quadrigemina, a small brainstem, and dif fuse hypoplasia of the cerebral white matter. In all cases, the corpus callosum was hypoplastic or aplastic. The aqueduct was patent in four of five cases. Asymmetrical reduction of the ventricular size and a r ippled ventricular wall were characteristic postshunt CT findings. Pro gressive macrocephaly and symptoms due to increased intracranial press ure were ameliorated by the shunt; however, the neurological outcome w as not improved by shunting. Of 14 patients who lived to be between 2 and 18 years of age, all are retarded. These results indicate that X-l inked hydrocephalus is not a disease of simple ventriculomegaly due to aqueduct stenosis alone but involves other complicated central nervou s system anomalies.