Abstract #3344

Efficient Measurement of Resting and Elevated Absolute CMRO2 and Their Within Session Repeatability in the Human Brain Using Calibrated FMRI

Alan J. Stone¹, Kevin Murphy², Ashley D. Harris², Richard G. Wise²

¹Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University , Cardiff, United Kingdom; ²Cardiff University Brain Research Imaging Centre, School of Psychology, Cardiff University, Cardiff, United Kingdom

We present a refined method for hyperoxic and hypercapnic calibration of BOLD signal that yields measurements of the absolute rate of cerebral oxygen consumption (CMRO2). We demonstrate that the measurements can be obtained in 9 mins, are repeatable within a scan session and are sensitive to sustained (18 min) task-related increases in absolute CMRO2. The sensitivity to sustained changes in CMRO2 indicates that the method proposed is promising for clinical or pharmacological applications in which CMRO2 is altered.