Diffusion-weighted imaging (A) and the corresponding apparent diffusion coefficient (B) image in MRI shows restricted diffusion within a dilated right PCS, suggestive of pyonephrosis. Note urothelial thickening
MRI confirmed left kidney intra-rotation with posterior hilum on sagittal plane. Contrast-enhanced sequences demonstrated normal renal arteries; a perfusion delay compared to right kidney was observed due to traction phenomena of vascular pedicle (Figures 4 and 5).