The kidney can be selected for CT examination. CT plain scan can observe whether the size, shape, density and contour of the kidney are abnormal, including the adrenal glands above the kidney, and generally cysts, calcifications and vascular smooth muscle lipomas can be diagnosed very clearly. In addition to plain scan, enhanced CT scan is needed for early stage kidney cancer. All renal malignant tumors have arterial phase enhancement. Therefore, when enhancing the scan, it is necessary to scan the arterial phase, venous phase and equilibrium phase to differentiate the tumor from three different time phases.