Repeatability of a quantitative multiparametric MRI protocol for imaging hypoxia, cellularity, and perfusion in a murine model of glioblastoma

Motivation: Heterogeneous distributions of hypoxic tissues lead to divergent radiotherapy response. Thus, developing a practical, accurate, and reproducible method of quantifying hypoxia is of great interest. Goal(s): Establish a repeatable, multiparametric MRI protocol for quantifying hypoxia. Approach: We induced C6 brain tumors in rats and conducted test-retest TOLD-MRI, DCE-MRI, and DW-MRI exams on each rat. We then analyzed the MRI data to identify spatially distinct physiological clusters within the tumor. Results: An initial assessment of repeatability of hypoxia, normoxia, and necrotic tissue localization within a tumor. Impact: Developing a quantitative and repeatable protocol for quantifying tumor hypoxia will have immediate applications in studies seeking to design, assess, and optimize radiotherapy regimens.