Evaluation of the lumbar and ventricular infusion test in the diagnostic strategy of pediatric hydrocephalus and the therapeutic implications

Abstract

Aim: To evaluate the infusion test as a diagnostic tool behind the choice of intervention in pediatric hydrocephalus.

Materials and methods: Intracranial pressure (ICP) measurement and infusion test were performed intraventricularly, by lumbar route, or combined in 40 consecutive children as a part of the standard diagnostic program in 1996-1999.

Results: The median age was 18.5 months, ranging from 2 weeks to 13 years. In the subgroup of patients with radiological aqueductal stenosis (N=14), mean lumbar/intraventricular ICP was 13 (3-35)/10 (2-27). Mean lumbar/ventricular R(out) were 18 (4-49)/17 (6-37). For patients with radiological communication between the third and fourth ventricles (N=14), the mean lumbar/intraventricular ICP was 11 (7-17)/9 (1-16). Mean lumbar/ventricular R(out) were 8 (3-11)/8 (4-12). A total of 13 patients had a shunt insertion, 10 had an endoscopic third ventriculostomy (ETV), 5 had endoscopic fenestration of a cyst, and 12 had no surgery. Of the patients initially treated with EVT, 50% had a shunt insertion shortly after. For communicating hydrocephalus, 75% of the patients initially not operated based on normal R(out) values ended up having a shunt insertion.

Discussion: R(out) has doubtful value as an indicator for conducting an operation or not and in the choice between EVT and shunt in children. This should be interpreted in the light of a growing understanding of hydrocephalus on a molecular level.