Intravenous pyelogram is not really painful, it is done by choosing to hit the contrast agent inside the vein, these contrast agents are excreted through the kidneys. In the process of renal excretion, the contrast agent is filtered through the bloodstream through the kidneys and excreted by the kidneys, at which time it can be clearly seen underneath the imaging, and the anatomical structures of the kidneys, the renal pelvis, the ureters, and the bladder will be visualized underneath the contrast agent. In fact, there is no pain, do this test can rule out many kidney diseases, such as congenital ureteral malformation, or chronic pyelonephritis has kidney hairy, thickening of the ureteral wall and so on. Even if there is a small amount of bleeding above the ureter, it can be seen under the contrast.