Low-dose spiral CT generally refers to low-dose CT examination of the chest, and the precautions to be taken during the examination are as follows: 1. Before the examination, patients are requested to try not to wear clothes, underwear or jackets with metal. If they do, the medical staff will remind the patient to take off the metal zipper clothes so that the metal will not cause artifacts that will affect the diagnosis; 2. Metal items such as lighters, necklaces, underwear shoulder buttons, etc. need to be removed to avoid artifacts that will interfere with the examination. In addition, low-dose chest CT examination can detect a variety of diseases, especially early diseases, such as early diagnosis of lung cancer. Early-stage patients do not have any symptoms, and most of them are found through physical examination and get timely diagnosis and timely treatment.