Long-term follow-up data from the shunt design trial

Background: A previously reported multicenter randomized trial assessed whe ther 2 new shunt valve designs would reduce shunt failure rates compared to differential pressure valves. The study did not show a significant differe nce in the time to first shunt failure. Patients entered the trial between October 1, 1993, and October 31, 1995. The primary results were based on th e patients' status as of October 31, 1996 (a minimum follow-up of 1 year). This report describes the late complications based on the patients' most re cent follow-up. Methods: Three hundred and forty-four hydrocephalic childre n at 12 North American and European centers were randomized to 1 of 3 valve s: a standard differential pressure valve; a Delta valve (PS Medical-Medtro nic) or a Sigma valve (NMT Cordis). Patients were followed until their firs t shunt failure. Shunt failure was defined as shunt surgery for obstruction , overdrainage, loculation or infection. If the shunt did not fail, follow- up was continued until August 31, 1999. Results: One hundred and seventy-se ven patients had shunt failure. Shunt obstruction occurred in 131, overdrai nage in 13, loculated ventricles in 2 and infection in 29. The overall shun t survival was 62% at 1 year, 52% at 2 yea rs, 46% at 3 yea rs, 41% at 4 ye ars. The survival curves for the 3 valves were similar to those from the or iginal trial and did not show a survival advantage for any particular va Iv e. Conclusions: Prolonged follow-up to date does not alter the primary conc lusions of the trial: there does not appear to be one valve that is clearly the best for the initial treatment of pediatric hydrocephalus. Copyright ( C) 2001 S. Karger AG. Basel.