What is the diagnosis?
Calculus in the right renal pelvis, with stranding around the proximal ureter from recent impaction.
Within the right renal pelvis a hyperdense focus is present with an oblong form on axial and a more rectangular form on coronal imaged. There is no hydronephrosis or hydroureter although the proximal right ureter is swollen with some surrounding stranding. The left collecting system is unremarkable.