Fig. 1.

Schematic overview of the segment changes for the different plan adaptation methods available in the treatment planning software for the 1.5 T MR-linac for plan adaptation on the daily anatomy and contours. A different background color (e.g. red or yellow) in the Beam’s eye view (BEV) indicates a different segment weighting. When performing plan adaptation methods using optimize weights (method D) or optimize weights and shapes (method F) starting with full fluence optimization, the original segments are discarded and new initial plan segmentation is performed. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)