Patients often reflect dizziness after CT, in fact, CT will not cause dizziness, especially flat scan will not appear dizziness. There may be some enhanced scanning of some patients with contrast reaction, there will be dizziness, dizziness may have several reasons: 1, the patient originally had underlying lesions, such as cerebrovascular lesions, usually have dizziness. After the CT examination, the psychological pressure increases, resulting in elevated blood pressure, and sometimes vasoconstriction occurs, resulting in poor blood supply to the brain, and thus transient dizziness occurs; 2, the patient is lying down when doing the examination, and gets up immediately after doing the examination, and postural dizziness occurs. The reason is that the patient suddenly changes from lying to sitting up, which changes the blood supply to the brain, and the blood supply decreases transiently, resulting in dizziness.