Reconciling differences between tumor oxygenation measurements performed using 19F NMR spectroscopy and imaging of perfluorocarbon (PFC) emulsions

The purpose of this study was to investigate methods for reconciling differences between tumor oxygenation measurements performed using ¹⁹F NMR spectroscopy and imaging of sequestered PFC´s. In vivo data from RIF-1 tumor bearing C₃H mice were acquired using ¹⁹F NMR spectroscopy and imaging, and the imaging data were analyzed via three different methods: (1) average of the T₁ map; (2) weighted average of the T₁ map which compensated for the spin density (M₀); and (3) region of interest (ROI) analysis of the tumor region. It was shown that compensating for M₀ in the imaging maps allowed correction of much of the discrepancy between tumor oxygenation values that were calculated from imaging and spectroscopic data