Normal pressure hydrocephalus in children and young adults.

Normal pressure hydrocephalus (NPH) is generally considered to be a disorder of adult and geriatric patients. We report four patients who are children or young adults with chronic neurological disorders, recent deterioration of their levels of function, normal cerebrospinal fluid (CSF) pressures, and ventricular enlargement. All four patients improved after the placement or revision of a ventriculoperitoneal shunt. Frequent symptoms and signs included irritability (three patients), vomiting (three patients), and abnormal limb posturing (two patients). Correct diagnosis was hampered by two factors: (a) Multiple or prolonged recordings of CSF pressures were invariably well within the normal ranges with respect to age, and (b) the patients had chronic neurological deficits. After ventriculoperitoneal shunting, subjective and objective improvement was seen in all cases. Young patients with large ventricles may benefit from shunting procedures despite low CSF pressures. These patients may be clinically identified by symptoms of new neurological dysfunction in cases of previously static neurological disease or acceleration of slowly progressive neurological dysfunction. Some of these underlying neurological disorders may predispose children and young adults to NPH.