Iopromide injection is a contrast agent, also known as a contrast agent. This contrast agent is mainly used for CT enhancement examinations or vascular type examinations. Its function is mainly to make the difference in density between normal and abnormal tissues appear more obvious, to clearly show the boundary between the lesion and the surrounding normal tissues, and to clarify the blood supply of the lesion. For example, if a plain examination shows a hypointense shadow on the liver, the plain examination cannot clarify the nature of the lesion. The contrast agent is injected to understand the enhancement pattern of the lesion, so as to determine whether the lesion tends to be benign or malignant. Contrast agents may cause allergic reactions, so patients who are allergic to iodine contrast agents or have severe hyperthyroidism should not undergo CT enhancement examinations or vascular examinations.