Imaging examinations can observe the morphological and functional changes of organs from different angles, and they are often used as an important basis for clinical diagnosis. Commonly used to examine various organs, blood vessels and tissues of the human body, common imaging examinations include: cerebral arteriogram, coronary arteriogram, gastrointestinal angiogram, tubal angiogram, lower limb venogram: 1, cerebral arteriogram: cerebral arteriogram can examine the arterial vascular condition of the brain, and is often used to observe whether the cerebral blood vessels are narrowed, blocked, bleeding, etc. It plays a very important role in the treatment of cerebral infarction, cerebrovascular tumors and cerebral hemorrhage. Coronary angiography: Coronary angiography is often used as an important diagnostic indicator of coronary heart disease, which is used to understand the condition of coronary artery vessel wall, whether the vessel is narrowed and the degree of narrowing through contrast agent, so as to clarify the diagnosis and differentiation of the disease; 3. Fallopian tube angiography can understand whether the fallopian tubes are patent and the morphology of the uterine cavity, and is often used to exclude the diagnosis of infertility caused by incompetence of the fallopian tubes; 5. Lower limb venography: lower limb venography can check whether the veins of the lower limbs and the iliac veins are under pressure with poor blood flow and blood pressure reflux, and is often used as an important basis for determining chronic venous insufficiency of the lower limbs and iliac vein compression syndrome. In case of transvascular injection contrast, patients are advised to compress the puncture site for 5-10 minutes to prevent bleeding; they can drink more water to facilitate the discharge of contrast agent from the body.