Detecting microcirculatory changes in blood oxygen state with steady-state free precession imaging.

Recently, it has been demonstrated that oxygen-weighted images of whole blood can be obtained with steady-state methods. In this article, based on computational and experimental models, we investigate the potential for employing this technique to monitor oxygen changes in microcirculation. Results show that oxygen-sensitive images of rabbit kidney and muscle may be obtained at high signal-to-noise ratio within a few seconds. The results also show that in steady-state free precession imaging, in addition to the exchange mechanism that generates oxygen contrast in blood, there are additional mechanisms that provide oxygen-sensitive contrast in microcirculation.