Apparent diffusion coefficient of kidneys with non-contrast magnetic resonance angiography for functional and anatomical assessment in renal artery stenosis

Figure 3 Unilateral renal artery stenosis with small-sized kidney. A: T2W magnetic resonance image (MRI) (coronal plane) showing atrophic right kidney (4 cm) and normal-sized left kidney (9.4 cm); B: Non-contrast MR angiography (INHANCE) in axial plane depicting diffuse stenosis of right renal artery; C-J: DW MRI image (C, E, G, I) in the axial plane with corresponding apparent diffusion coefficient (ADC) map (D, F, H, J) of bilateral kidneys showing manually drawn region-of-interest (ROI) placed in the upper (C, D), middle (E, F) pole of bilateral kidneys, lower (G, H) pole region of right kidney and lower (I, J) pole region of left kidney. On the right side, as the kidney is atrophic, the ROI was placed in the corticomedullary region, whereas on the left, the ROI was placed separately in the cortex and medulla. Mean corticomedullary ADC of the right kidney was 1.43 × 10^-3 mm²/s. Mean cortical ADC and medullary ADC values of the left kidney were 194 × 10^-3 mm²/s and 1.91 × 10^-3 mm²/s, respectively.