[Aqueductal stenosis in the neurofibromatosis type 1. Presentation of 19 infantile patients].

To present a series of infantile patients with aqueductal stenosis associated with neurofibromatosis type 1 (NF1). Nineteen patients with ages below 16 years, 11 girls and 8 boys, with NF1 presented hydrocephalus due to aqueductal stenosis. All patients, except one who died before the imaging study was performed and was diagnosed by autopsy, were studied by pneumoencephalography (since 1965 to 1974), computerized tomography (CT) (since 1975 to 1984), magnetic resonance (MR) or MR and CT (since 1985 to 2004) (two children had been studied by pneumoencephalography some years before) most times to discard optic pathway tumor and, in few patients, because of intracranial hypertension. All patients showed three ventricular hydrocephalus with aqueductal stenosis. Eleven patients showed optic pathway tumor. One patient had a benign aqueductal tumor that impaired the normal flow of cerebrospinal fluid. Neurological features of hydrocephalus occurred very rapidly in some patients and after several years of evolution in others. Two boys showed precocious puberty. All patients were treated with shunt. In our series, aqueductal stenosis occurred in about 5% of children with NF1. Aqueductal stenosis and hydrocephalus were identified at a short age because many patients were studied suspecting optic pathway tumor. Eleven patients (about 60%) associated optic pathway tumor and aqueductal stenosis.