Assuming that the anatomy of the treatment area remains constant during the treatment and does not change throughout the treatment, the treatment plan is usually made once at the beginning of the treatment in the patient who started radiotherapy and the same plan is used throughout the entire treatment.
However, there may be daily changes in the anatomy determined at the beginning, the shape and position of the treated target. In the shape and position of the target area during the treatment period; There may be shrinkage or growth in the tumor, as well as differences in the filling of organs with anatomical spaces or cavities, movements of organs, changes in the patient's weight during treatment, or differences due to hypoxic changes that may occur in the tumor. As a result, it may cause changes in the doses planned to be given in the treated area and around the organs to be protected.
ART is the change of the radiotherapy plan applied to the patient under the image guidance according to the needs during the treatment process, taking into account these changes in the field of radiotherapy.