Outcome analysis of initial neonatal shunts: Does the valve make a difference?

Objective: Ventriculoperitoneal shunts have one of the highest complication rates of all neurosurgical procedures. The purpose of this study was to identify factors associated with malfunction of shunts placed in infants with neonatal hydrocephalus, with the goal of maximizing long-term shunt survival. Methods: We performed a retrospective chart review of 200 consecutive patients less than 1 year old who underwent primary intracranial shunt placement for hydrocephalus by one of two experienced pediatric neurosurgeons at a single institution. A multivariate analysis was conducted to identify variables that were statistically independent predictors of a shunt malfunction or problem. Results: Adequate data were available for 158 patients, with a mean follow-up of 39.8 months (range 6-99 months). Variables tested for independent prediction of shunt revision included the etiology of the hydrocephalus, gestation period, age at shunt placement, surgeon, ventricular catheter entry site and valve opening pressure. Frontal versus occipital catheter entry site was not associated with a different revision rate. The only significant controllable factor associated with shunt malfunction was the valve opening pressure. The revision rate per year of follow-up was 4 times higher for patients with no valve or a low-pressure valve than for patients with a medium- or high-pressure valve. Conclusions: This retrospective review demonstrated that the valve opening pressure is an important component of the shunt complication rate. A prospective multicenter randomized trial is warranted to further evaluate the conclusions of this study.