Varian Medical Systems Inc
SRS CONTOURED MULTI-LAYER MULTILEAF COLLIMATOR

Abstract:

An apparatus includes a first multileaf collimator comprising a plurality of pairs of beam-blocking leaves each comprising an end portion. The end portions of the beam-blocking leaves of one pair are contoured to allow forming a first aperture when the beam-blocking leaves of the pair are closed. The first aperture has a closed shape such as a circle in a beam's eye view.