Transcranial Doppler Ultrasound Role for Patients with Traumatic Brain Injury

Abstract

Neurologists, neurosurgeons, and neurointensivists, including military, have a large armamentarium of diagnostic and monitoring devices available to detect primary and secondary brain injury and guide therapy in patients with acute traumatic brain injury (TBI) to avoid cerebral ischemia due to the posttraumatic vasospasm (PTV) and intracranial hypertension (ICH). This review summarizes the advantages and the specific roles of transcranial Doppler (TCD) ultrasonography for patients with acute and longterm effects of TBI. In critical care setting numerous publications showed that TCD is predictive of angiographic PTV and onset of ICH. The post TBI status of cerebrovascular reactivity and cerebral hemodynamics also has important implications with regard to the treatment of long-term effects of mild TBI (mTBI). Today it is abundant evidence that TCD is an important tool for monitoring the natural course of acute moderate and severe TBI, for evaluating the effect of medical treatment or intervention, for forecasting, and for identifying high-risk patients for onset of cerebral ischemia after TBI. TCD makes good clinical and economic sense as it is a reliable, quantitative, non-invasive and non-expensive “biomarker” to the acute clinical manifestations of TBI. TCD clinical utilization holds promise for better detection, characterization, and monitoring of objective cerebral hemodynamics changes in symptomatic patients with TBI not readily apparent by standard CT or conventional MRI techniques. TCD utilization will improve the sensitivity of neuroimaging to subtle brain perturbations and combining these objective measures with careful clinical characterization of patients may facilitate better understanding of the neural bases and treatment of the signs and symptoms of TBI. This review summarizes the advantages and the specific roles of TCD ultrasonography for patients with acute and long-term effects of TBI.