Lung enhancement CT is done according to the following steps: i. Because lung enhancement CT involves the use of iodine, intravenous use of iodine, like any other intravenous medication, may result in allergies and other adverse reactions, so the patient should be informed as well as specifically asked about any history of drug allergies, and sign an informed consent form. Second, lung enhancement CT does not require fasting, but metal buttons and chains on clothing should be removed before lung enhancement CT. Third, lung enhancement CT needs to follow the doctor’s instructions, deep inhalation after holding your breath lying still on the lung CT bed. The difference between lung enhancement CT and normal lung CT is that the former can better identify benign and malignant diseases, especially for the relationship between blood vessels and lesions, can be more clearly seen.