Representative TI = 6000 ms image, lung density (S0<sub>air</sub>), R1<sub>air</sub>, R1<sub>O2</sub> maps of a control and PPE-challenged mouse lung.

<p>The maps are overlaid on TI = 6000 ms image acquired when animals were breathing air (a). ΔR1 (oxygen uptake), ΔR2* (oxygen delivery) maps for the same control and a PPE-challenged mouse (b). The challenged mouse exhibits less uniform distributions of ΔR1 and ΔR2* suggesting that the oxygen uptake and delivery to the lung were more heterogeneous. Regions of spatially matched ΔR1 and ΔR2* are indicated by arrows. Mean ΔR1 assessed in 20 bins based on ΔR2* for control (open squares) and PPE-challenged (filled squares) mice, showing excellent correlation between ΔR1 and ΔR2* (c).</p>