MR CSF Flow Examination as a Non-Invasive Method of Determining Shunt-Independent Hydrocephalus in Children with Implanted Ventriculoperitoneal Shunt

Abstract

The study discusses the value of MR examination of CSF flow through the cranial part of the ventriculoperitoneal shunt in the evaluation of shunt-dependent hydrocephalus. Sixteen patients aged eight to 18 years were examined in the course of many years of treatment using the ventriculoperitoneal shunt. No clinical manifestations of shunt obstruction had been observed in any of the patients prior to MR examination. A Signa Horizon 1.5T (GEMS) unit was used. Axial and sagittal T1- and T2-weighted images were performed to find the ventriculoperitoneal shunt canal. A 2D CINE/GR/PC sequence was performed in the plane perpendicular to the shunt canal. CSF-flow was calculated by the Flow Analysis program. Patients were divided into two groups: 1) no CSF-flow was noted in five children indicating shunt-independent hydrocephalus; 2) CSF-flow was present (average flow volume from 0.1 to 1.9 ml/min) in 11 children, distinguishing the group with shunt-dependent hydrocephalus. Conclusions: 1) MR CSF flow examination will establish the absence or presence of CSF flow and determine its direction and velocity. 2) With no clinical manifestations of shunt impatency the absence of flow in the shunt canal found in MR CSF flow examination may indicate shunt-independent hydrocephalus. 3) When the CSF flow in the shunt is found in MR shunt-dependent hydrocephalus is diagnosed.