Noninvasive CSF shunt patency evaluation by superb microvascular imaging

Abstract Background and Objectives Occlusion of a ventriculoperitoneal shunt system is a potentially life threatening complication in patients suffering from hydrocephalus. However, there is no imaging established as standard approach in this acute setting. In the present study, we evaluate the use of superb microvascular imaging for investigation of the patency of ventriculoperitoneal shunt systems. Methods Simulation of low flow rates of cerebrospinal fluid through a small diameter CSF shunt system was performed in a dedicated phantom in order to proof the principle of superb microvascular imaging (SMI) being feasible for the measurement of slow liquor flow through the dedicated CSF shunt system. Results SMI is able to detect low flow rates in CSF shunt systems effectively and fast. Visualization of a Doppler ultrasound flow wave pattern in the VP shunt system after the reservoir has been pressed confirms patency. Conclusion SMI is an effective method for evaluating CSF shunt patency and diagnosing shunt obstruction. This bears the potential to facilitate evaluation of clinically symptomatic VP shunt patients in an acute setting. Further evaluation of ultrasound flow patterns is granted.