Cerebrospinal fluid dynamics and cerebrospinal fluid infusion in children. Part II: Clinical application of lumbar cerebrospinal fluid infusion in children with macrocephaly and normal growth rate of the head circumference.

In fourteen children with macrocephaly and a normal growth rate of the head circumference, the CSF dynamics were studied by means of the lumbar CSF infusion test with constant flow. We discuss the significance of the outflow resistance together with the advantage of the Pressure Volume Index, which constitute the major parameters of the test. On the basis of computed tomography, we were able to show a differentiation in macrocephaly between megalencephaly, so-called external ventricular obstructive hydrocephalus and communicating hydrocephalus. We were not able to establish a disturbance of the CSF dynamics in megalencephaly and external ventricular obstructive hydrocephalus. In communicating hydrocephalus, CSF absorption was normal, whilst the Pressure Volume Index was elevated. As far as we have been able to ascertain, we are the first in the field to point to a positive correlation between ventricular size and Pressure Volume Index in children with moderately enlarged CSF-spaces.