Perfusion Brain CT Assessments

Perfusion Brain CT is one of several new techniques that have become available thanks to the development of high-speed helical CT scanners.  This technique allows us to detect and evaluate the earliest phases of stroke, in the crucial moments when therapy is possible before permanent stroke damage occurs.  This sensitive look at acute brain ischemia during the therapeutic window of opportunity is a time when a routine CT study shows a normal appearance to the brain.  Perfusion CT assessments of Blood Flow, Mean Transit Time, and Cerebral Blood Volume, yield important information regarding size and location of acutely ischemic tissue and allow critical decisions to be made regarding balance of treatment opportunity and relative risk.  In addition to the time delay since the onset of symptoms, factors in this assessment include the size and location of the ischemic region, the specific site of vessel narrowing or occlusion.

For patients with acute stroke symptoms presenting to the Emergency Room at St. Joseph's Hospital within the time window of opportunity for intervention, we employ a special "Stroke Alert" protocol.  This protocol employs conventional CT scanning, CT angiography, and Perfusion CT methods in order to allow us to evaluate in the fastest and most effective way whether a patient is a candidate for acute thrombolytic treatment.