Pyelogram, also called intravenous pyelogram, is a method of visualizing the calyces, pelvis, ureters and bladder of the body by intravenous injection of organic iodine, which is then filtered through the glomerulus and drained into the urethra. It can show the entire urinary tract and the excretory function of the kidneys. It is a relatively simple test and is less painful for the patient. It can be used when you need to know the functional pattern of the urinary system, its location and patency, and its relationship to surrounding structures. This test can be used for pyelonephritis, tuberculosis, and urinary calculi. Patients with renal failure are relatively contraindicated; patients with iodine allergy cannot use it because iodine is used in the process; multiple myeloma and pregnant women generally do not do this test, which is its contraindication. At present, CTU is basically used clinically instead of pyelogram, and CT examination has fewer side effects and high accuracy.