The following matters should be noted during the head CT examination: 1. Metal objects should be removed, such as hairpieces, earrings, necklaces, glasses and hats, because some of these objects contain metal that can affect the examination results. 2. When doing the head CT, if it is not enhanced CT, it can be examined after meals, if it is to be enhanced CT, it should be done on an empty stomach. 3. 4. When doing CT head examination, women of pregnancy age should pay attention to the fact that they should not do it during pregnancy, and should pay attention to the indications when doing CT head examination. The indications must be strictly understood.