Flow Control versus Antisiphon Valves: Late Results Concerning Slit Ventricles and Slit-Ventricle Syndrome

Introduction The aims of the study were firstly to investigate the time course of development of slit ventricles (SV) and slit-ventricle syndrome (SVsyndrome) in hydrocephalic patients shunted as infants and secondly to assess the difference in incidence of SV and SVsyndrome in 2 groups of patients - group A with a conventional valve and group B with an anti-siphon valve. Patients and Methods 27 infant patients with hydrocephalus received a ventriculoperitoneal shunt and were followed prospectively with annual clinic visits and at least two CT or MRI scans postoperatively. The scans were assessed for SV, and ventricular and parenchymal surface and cortical mantle thickness were measured. Revisions for shunt malfunction were recorded. Results SV were more frequent than SVsyndrome and developed within 6.5 months postoperatively in 21 % of patients and 48 % after 6 years. No significant difference in incidence of SV or in the surface and cortical mantle thickness were found between the two groups. Two patients (40 %) with early development of SV developed SVsyndrome, and the relative risk for shunt revision was significantly higher in patients who developed SV early. 48 % of patients did not need emergency shunt revision during the first 9 years. Conclusion SV develop over years. The majority of patients with SV remain asymptomatic. No significant difference between the two groups was found concerning SV and SVsyndrome. If SV develop early in the postoperative period, complications are more frequent in the long-term, so elective valve adjustment should be considered.