Use of an adaptive radiation therapy framework includes determination of a
radiation beam size, radiation beam shape, and radiation beam position
for delivering at least a portion of a prescribed radiation dose to a
target volume based on first image data of a patient, and selection of
one radiation therapy process from an available first process and second
process. The first radiation therapy process comprises acquisition of two
dimensional image data of the patient, determination of a position offset
based on the two-dimensional image data and on the first image data, and
movement of the patient based on the position offset. The second
radiation therapy process comprises acquisition of three-dimensional
image data of the patient, determination of a second position offset
based on the three-dimensional image data and on the first image data,
and movement of the patient based on the second position offset.