Low-dose spiral CT and enhanced CT are different, as follows: 1. Low-dose CT scan is a kind of plain scan, that is, a scan without contrast injection, and the amount of radiation received is low; at present, it is most suitable for lung disease examination, and other parts are generally not low-dose scan; enhanced CT is a CT examination after intravenous injection of iodine-containing contrast agent, so they are different; 2. The plain scan is mainly suitable for traumatic diseases or bleeding diseases, or common inflammation or degenerative changes, such as degenerative changes of lumbar spine, disc protrusion and other diseases; CT enhanced scan is mainly suitable for differential diagnosis of tumor diseases, such as understanding whether the blood supply of tumor is rich, whether it invades the surrounding structures, whether there is metastasis and so on, which is directly related to clinical treatment, so the doctor needs to let the patient do Therefore, the doctor needs to have the patient undergo enhancement to fully evaluate the disease. Enhancement scan is suitable for examination of large blood vessels and cardiac vessels, such as coronary heart disease examination, pulmonary embolism examination, aortic aneurysm examination, head and neck vessels and lower limb vessels. Therefore, different choices should be made depending on the patient’s condition.