Measuring changes in tumor oxygenation.

Publisher Summary This chapter discusses the measurement of changes in tumor oxygenation. The oxygen pressure determinations could be of great clinical value and they are also vital to many laboratory investigations of new drugs and studies of tumor development. Blood oxygen level dependent (BOLD) contrast proton nuclear magnetic resonance (NMR) facilitates rapid interrogation of vascular oxygenation, and is particularly appropriate for examining dynamic responses to interventions. Both spectroscopic and imaging approaches have been applied to tissue oxygen pressure measurements depending on the available signal to noise. It appears that uptake and distribution efficiency vary with tumor type, but in general, maximum signal is detected from the tumor periphery corresponding with regions of greater perfusion. The various aspects of fluorocarbon relaxometry using echo planar imaging for dynamic oxygen mapping (FREDOM) are elaborated. The results suggested FREDOM as a valuable tool for assessing the dynamic time course of interventions to provide clear insight into the mode of action of therapeutic approaches and aid in the high-throughput screening of new drugs, such as vascular targeting and antiangiogenic agents.