Introduction: ETV is increasingly used in place of shunt revision for shunt malfunction (secondary ETV). In this meta-analysis, we sought to explore the impact of hydrocephalus aetiology on outcome of secondary versus primary ETV in the pediatric age group.
Methods: Systematic and independent MEDLINE searches by two authors. Inclusion criteria: (1) studies including a predominance of children and adolescents (=18); (2) description of clinical outcomes after secondary ETV. ETV success was defined as the lack of need for a shunt.
Results: Fifteen studies were included. 519 patients underwent a secondary ETV for shunt malfunction (85%) or infection (15%). The mean age was 9.8 years (95% CI 7.9-11.8 years). Aetiology of hydrocephalus was: chiari malformation (31.5%), aqueductal stenosis (29.3%), intraventricular haemorrhage (17.7%), meningitis (13.1%) and tumours (8.4%). The overall ETV success rate was 70.5% over a median follow-up period of 45.5 months (range 1-190 months). For acqueductal stenosis and tumours, there was no significant difference in success rate between primary and secondary ETV (OR = 1.19, 95% CI 0.46-3.11; p = 0.74). Secondary ETV had a significantly higher success rate than primary ETV in patients with hydrocephalus due to chiari malformation (OR = 5.57, 95% CI 2.81-11.00; p < 0.001) and haemorrhage or infection (OR = 5.79, 95% CI 2.46-13.61; p < 0.001).
Conclusions: The efficacy of secondary ETV varies depending on hydrocephalus aetiology. Secondary ETV may be more efficacious than primary ETV in certain disease states due to a state of acquired acqueductal stenosis with chronic CSF diversion.
Patient Care: This meta-analysis will stimulate discussion and could act as a foundation for prospective studies looking at secondary ETV.
Learning Objectives: By the conclusion of this session, participants should be able to:
- Appreciate the heterogeneity of published studies relating to ETV performed after shunt malfunction
- Appreciate the differences in outcome between secondary versus primary ETV