Fig. 5.

Example OE-MRI parametrical maps in a patient with a primary tumour with residual disease post radiotherapy treatment (patient number 3). High estimated hypoxic fraction (73.5%) is shown on a T1-weighted VIBE image with overlaid parametric ΔT1 map of the primary tumour (a, d, axial and coronal plane, respectively) and overlaid statistical map of ΔT1 times (b, e). Blue colour indicates a statistically significant decrease in T1 times, white indicates no statistically significant change, and red indicates statistically significant increasing T1 times. c Time series of T1 times averaged over the entire primary tumour VOI and over those voxels with significantly decreasing T1 times only. f Histogram of ΔT1 times for the entire primary tumour VOI. OE-MRI Oxygen-enhanced magnetic resonance imaging, VIBE Volumetric interpolated breath-hold examination, VOI Volume of interest