Related Experiment Video
Updated: May 12, 2026

Functional Transcranial Doppler Ultrasound for Monitoring Cerebral Blood Flow
Published on: March 15, 2021
Transcranial Doppler identifies a malfunctioning extraventricular drain
David R Mayans1, Dana B Meads, Patrick S Reynolds
1From the Department of Neurology, Wake Forest University School of Medicine, Winston-Salem, NC, 27517.
Transcranial Doppler (TCD) is an invaluable tool allowing real-time monitoring of physiologic blood flow velocity changes. We present a case where TCD monitoring for vasospasm after subarachnoid hemorrhage identified blood flow velocity changes consistent with sudden increased intracranial pressure (ICP) due to a malfunctioning extraventricular drain. The primary team was alerted to these findings, and immediately revised her shunt with normalization of ICP and TCD. Serial TCD monitoring allowed identification of an imminently fatal complication in time to allow a life saving intervention. TCD is a portable, inexpensive, real-time tool providing important physiologic data regarding blood flow velocities and intracranial pressure that is crucial to the care of critically ill patients.
Transcranial Doppler (TCD) is an invaluable tool allowing real-time monitoring of physiologic blood flow velocity changes. We present a case where TCD monitoring for vasospasm after subarachnoid hemorrhage identified blood flow velocity changes consistent with sudden increased intracranial pressure (ICP) due to a malfunctioning extraventricular drain. The primary team was alerted to these findings, and immediately revised her shunt with normalization of ICP and TCD. Serial TCD monitoring allowed identification of an imminently fatal complication in time to allow a life saving intervention. TCD is a portable, inexpensive, real-time tool providing important physiologic data regarding blood flow velocities and intracranial pressure that is crucial to the care of critically ill patients.

