2017_SBRT_Course Book

Discussion: Clinical Relevance

▪ Should we measure intra-fraction motion? ▪ Yes, at planning in order to individualize the safety margin (and to determine the time-averaged mean position) ▪ Should we correct for intra-fraction motion? ▪ Amplitude seems to have a minor effect on the margin. However, ▪ for central lesions and lesions close to the thoracic wall the penumbra will be sharper ▪ Take care of small lesions and large amplitudes ▪ Should we correct for inter-fraction motion? ▪ YES! ▪ Dosimetrical effects? ▪ Be cautious for fast and single-fraction treatments