Tumor oxygen tension: measurement using Oxygent as a 19F NMR probe at 4.7 T

We have used Oxygent (an emulsion of perflubron [PFOB]) to measure pO2 in a Dunning prostatic adenocarcinoma non-invasively using 19F NMR spectroscopy. We have confirmed a linear relationship between the spin-lattice relaxation rate (R1) and pO2 and we have assessed the effect of temperature. R1 of the individual resonances of Oxygent is considerably more sensitive to changes in pO2 than other PFC emulsions, whilst being considerably less sensitive to interference from temperature variation. Oxygent has two well resolved resonances (delta delta approximately 18ppm) and these were both exploited to estimate tumor pO2 = 47 +/- 5 torr.