Pediatric Shunt Malfunction without Ventricular Dilatation

Background/Purpose: Symptomatic ventriculoperitoneal shunt (VPS) malfunction can occur without progressive ventricular dilatation on imaging studies. A review of VPS revisions performed during an 18-month period was conducted to better characterize this cohort. The incidence of VPS malfunction without ventricular dilatation and the clinical features that may predispose to its occurrence have not been previously described. Methods: A retrospective review was conducted of all patients under the age of 18 who underwent VPS revision due to shunt malfunction from June 2001 to December 2002. The incidence of various factors that might correlate with the development of low compliance ventricles was examined. Results: One hundred and seventy-seven patients underwent a total of 287 VPS revisions during the study period; 16 patients (9%) had signs of raised intracranial pressure and showed no radiographic evidence of progressive ventricular dilatation. History of prior shunt-related ventriculitis positively correlated with the development of low compliance ventricles (Fisher’s exact test, p = 0.043). Conclusion: Nine percent of pediatric patients with symptomatic VPS malfunctions lack radiographic evidence of progressive ventricular dilatation on imaging studies. Patients with prior shunt infections are particularly at risk, necessitating increased vigilance when clinical signs and symptoms are apparent.