17:54 187. A Simultaneous Measurement of Relative CMRO2 with MRI & FMISO Uptake with PET in Glioblastoma
Heisoog Kim1, Ciprian Catana1, Grae Arabasz1, Div Bolar1, Elizabeth R. Gerstner2, Tracy T. Batchelor2, Rakesh K. Jain3, Bruce R. Rosen1, A. Gregory Sorensen1
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.