Milani B, et al. - Researchers here aim to develop a new method to analyse blood oxygenation level-dependent magnetic resonance imaging (BOLD-MRI) signals and apply it to chronic kidney disease (CKD) patients and controls. Here, they analyze MR images with the new twelve-layer concentric objects method (TLCO) that divides renal parenchyma in 12 layers of equal thickness. Using this new TLCO method, it is confirmed that in humans, renal cortical oxygenation is reduced in CKD and that the level of cortical oxygenation correlates with CKD severity.