Ultrasound characterization of interface oscillation as a proxy for ventriculoperitoneal shunt function.

Abstract

Hydrocephalus, where cerebrospinal fluid (CSF) production rate is greater than reabsorption rate, leads to impaired neurological function if left untreated. Ventriculoperitoneal shunts (VPS) are implanted in the brain ventricles to route CSF. VPS systems have a high failure rate, and failure symptoms resemble symptoms of common maladies. The current gold standard for shunt diagnosis, surgical intervention, poses high risk and requires an expensive procedure for patients. Current non-invasive methods lack proper insight to assist physicians. We propose a noninvasive method of characterizing the oscillation of the shunt's pressure-relief valve to assist physicians in shunt diagnosis. Brightness-mode and motion-mode ultrasound images can be used to determine fluid flow. Blockage in the system could be detected by observing the phase change of the ultrasound signal in different flow cases with or without perturbation. Future testing and implementation can allow for the use of this method in localizing and identifying the modality of failure.