Evaluation of the ETV success score and its predictive value in pediatric occlusive hydrocephalus: implications for patient counseling

Endoscopic Third Ventriculostomy (ETV) is a well-established treatment for pediatric hydrocephalus, particularly in cases of aqueductal stenosis. The ETV Success Score (ETVSS) is a predictive tool widely used to estimate the likelihood of ETV success based on factors like age. Its accuracy, especially in infants under 3 months, is still debated.

This study evaluates the age-dependency of ETV success in 54 pediatric patients compared to ETVSS predictions. Patients were divided into age and pathology groups according to Kulkarni. Success was defined according the ETVSS criteria. Minimum follow-up was 12 months and included MRI to demonstrate a flow void at the floor or the third ventricle.

Our institutional data revealed a higher overall success rate SR (88%) compared to the ETVSS-predicted rate of 73%. Despite small numbers within subgroups, especially in very young children < 1 month, the success rate was higher than predicted by ETVSS.

Our results show significantly higher actual SR across all age groups compared to ETVSS predictions (p = 0.035) when selected and performed by an experienced physician. The age groups > 1 year had significantly higher SR close to 100% (p < 0.0001 and p = 0.0038, respectively). This suggests that ETV may be underutilized, particularly in infants, where predicted success rates are pessimistic.

ETVSS is a useful tool for counseling of parents, but differences in institution-specific outcomes should not be neglected. Depending on that, physicians might opt in favor of ETV as primary treatment in occlusive hydrocephalus of very young children, counterbalancing risks and sequalae of VP-shunting.