[Studies on the incidence and clinical importance of the valve independent, arrested hydrocephalus (author's transl)].

Between 1964 and 1974 193 infants up to the age of 2 years were treated for progressive hydrocephalus by means of a ventriculo-atrial shunt. Long term follow-up studies were possible on 148 children. Among these 94 have functioning and 54 non-functioning valves. The criteria for the non-function were based on either plain X-rays of the skull and thorax (disconnection of the catheters, distal end of the cardiac catheter above D 2), direct punctures of the antichamber and contrast medium studies of the diversional system. 35 children with non-functioning valves were normal in their mental and motor development, 9 were retarded according to their primary brain damage, 10 patients showed signs of chronic increased intracranial pressure. These results suggest, that about one fourth of the valve treated patients develop a state of valve independency.