Reduced synaptic transmissions during states of reduced consciousness cause a slowdown in the cerebral metabolic rate of oxygen (CMRO2) and glucose utilization. Prior methods based on PET and tracer kinetics involving repeated blood sampling are not practical in a clinical setting. Here we used whole-brain MR oximetry at 3-second temporal resolution with simultaneous EEG recording to evaluate the feasibility of in-scanner monitoring of brain oxygen metabolism during wakefulness and sleep. The results in three subjects show reduction in CMRO2 up to 15% following onset of sleep paralleling increased delta wave EEG activity and reduction in heart rate.
This abstract and the presentation materials are available to members only; a login is required.