Xenon/CT provides quantitative CBF data that has a proven record of being both safe and prognostic for decision making. The technique itself has been extensively validated. Modern equipment has allowed for integration of the data into immediate bedside decision-making with the use of a portable head CT scanner and improved data processing. The use of xenon/CT in decision making in traumatic brain injury may have a high utility in determining whether a specific treatment— whether it is hyperventilation, induced hypertension, or other intervention—is in fact helpful to the individual patient. This can allow for decision making based on an individual patient’s physiology rather than generalized guidelines which may, in some cases, even be harmful.