FIG 2. Example of a xenon-enhanced CT CBF analysis for a patient at moderate risk for ischemic infarction after carotid occlusion. Quantitative BTO CBF analysis (BTO R ICA) identified decreased perfusion of the right ICA. The patient then underwent cerebral revascularization followed by carotid occlusion, with restored baseline CBF postoperatively. STA indicates superficial temporal artery. Each column represents a different brain level of CBF 5 min apart.