Evaluation of Relative CMRO2 from BOLD & CBF Changes in Hyperoxia: Significant Increase of Oxygen Consumption rate in Glioblastoma Heisoog Kim1,2, Ciprian Catana1, Kim Mouridsen1, Div Bolar1, Elizabeth R. Gerstner3, Tracy T. Batchelor3, Rakesh K. Jain4, Bruce R. Rosen1,2, A. Gregory Sorensen 1Radiology, A. A. Martinos Center, Charlestown, MA, USA; 2HST/NSE, Massachusetts Institute of Technology, Cambridge, MA, USA; 3Neurology, Massachusetts General Hospital, Boston, MA, USA; 4Radiation Oncology, Massachusetts General Hospital, Boston, MA, USA

17:54 187. A Simultaneous Measurement of Relative CMRO₂ with MRI & FMISO Uptake with PET in Glioblastoma

Cerebral metabolic rate of oxygen (CMRO2) is one of the characteristics utilized to investigate metabolic changes in tumor oxygenation under different baseline physiologies. Based on simultaneous BOLD-ASL measurements, relative CMRO2 in hyperoxia in glioblastoma (GBM) were quantitatively evaluated. Elevated BOLD and reduced CBF signal changes during 100% oxygen breathing were observed in glioblastoma. Our data validated the coupling between BOLD and CBF in Davis model in GBM patients. Remarkably, oxygen-induced relative CMRO2 estimated from these measurements showed a significant increase (44%) in tumor and peritumoral regions. It implies that hyperbaric oxygen administration manipulates the oxygenation metabolism in cancer cells.