Advanced Brain Imaging Studies Should Not Be Performed in Patients With Suspected Stroke Presenting Within 4.5 Hours of Symptom Onset

For years after the US Food and Drug Administration approved intravenous recombinant tissue-type plasminogen activator (rtPA) for acute ischemic stroke, my friend, Lou Caplan, argued eloquently that thorough knowledge of each patient's vascular anatomy must be obtained before administering a potentially dangerous thrombolytic1; I argued the opposite in countless hallway, pub, and platform debates with Lou and others.2 Because time is brain, I believed, nothing should delay prompt thrombolysis. Jeff Saver estimated that for every 1-minute delay, an ischemic brain loses 1.9 million neurons.3 Because vascular imaging involved invasive angiography, or time-consuming transcranial Doppler, it was easy to oppose vascular imaging before thrombolysis. However, then rapid, reliable CT angiography and CT perfusion came along, and I succumbed—who could ignore those beautiful perfusion images? It appeared that finally we had the means to select patients for thrombolytic therapy rationally and thus perhaps to reduce the risk of hemorrhage …