All of the above.
Explanation:
Renal scan is a nuclear medicine examination in which a small amount of radioactive particle is injected into the veins of hand or arm, the amount of radioisotope injected varies according the examination.The injected radioisotope releases Gamma rays. The scanner will detect the gamma rays, hence create the images of that particular area.
This is done to check weather the kidney is properly functioning or not. It checks both structural(size and shape) and functional abnormalities. It requires 45minutes -3hours for the examination to take place.