Fig. 3

Exemplary 3D conformal emergency treatment plan dose distributions on axial slices of patient 1 (re-planned after 1st fraction) and the resulting dose difference map: a original plan calculated on diagnostic CT (no reference marks, curved CT couch surface, no immobilization devices), b same treatment plan calculated on the planning CT, which was acquired after the first fraction (rigid registration via isocenters; one vertebra was used as an anatomical reference structure for isocenter placement), c Dose difference map (cut off for doses < 10% of prescribed dose) with dose differences < 1% in the large central area