Background:The early posttraumatic period is critical in patients with traumatic brain injury (TBI) because of the increased risk of secondary ischemic injuries to the injured brain. For these patients, cerebral perfusion pressure (CPP) monitoring is recommended. This, however, requires an invasive device to measure intracranial pressure (ICP). Transcranial Doppler (TCD) ultrasonography is an effective, noninvasive method for the detection of cerebral hemodynamic changes. Use of the dimensionless TCD-pulsatility index (PI) has the advantage of eliminating errors in measurements due to insonation angle variations.Material/Methods:We investigated 37 patients with severe TBI (GCS

Keywords: Brain Injuries - complications, Brain Injuries - pathology, Brain Injuries - ultrasonography, Brain Ischemia - complications, Brain Ischemia - pathology, Brain Ischemia - ultrasonography, Hemodynamic Processes, Perfusion, Pressure, Time Factors, Ultrasonography, Doppler, Transcranial, Brain Injuries - ultrasonography, Brain Ischemia - ultrasonography, Hemodynamics, Perfusion, Pressure, Time Factors, Ultrasonography, Doppler, Transcranial