Cerebrospinal fluid dynamics in the Arnold-Chiari malformation.

A myelomeningocele associated with the ArnoldChiari malformation is now one of the commonest neonatal surgical emergencies. Hydrocephalus used to be the main cause of death in these infants during the first year of life, but since the advent of ventriculo-atrial shunting procedures the mortality and morbidity have improved. However, the management of the hydrocephalus still remains a serious problem. In the past, assessment of the hydrocephalus has depended upon the correlation of the clinical signs such as skull size, separation of the sutures, tension of the anterior fontanelle with the CSF pressure, dye studies, and air ventriculography. More recently radio-isotopes have been used to study the production, circulation, and absorption of the CSF. The aim of the present investigation was to measure the movement of CSF before and after ventriculoatrial shunts in infants with the Arnold-Chiari malformation.