This will vary according to the experience and requirements of different doctors and the requirements of different hospitals. Generally speaking, the results of large examinations are now mutually recognized nationwide, and there are some doctors or hospitals that do not recognize the results of other hospitals, so they need to be treated differently. The general principle is that if there is no significant change in the condition, there is no need to repeatedly repeat MRI or CT examinations, unless The quality of the original examination is poor.