Physics Bucharest 2017

VMAT – Plan optimization

Otto K et al. Med Phys 2008

• The algorithm is based on progressive beam angle sampling to optimize a large number of apertures using direct aperture optimization (coarse-to-fine scheme) • starts with a small number of beams and large angular spacing, and gradually inserts new beam angles to be optimized • Geometric connectivity is facilitated by initializing the shapes of new apertures with shape interpolation between its neighbors and by constraining maximum leaf travel near the end of the optimization process