Dose Course 2018_Flipping book

concepts:

Finite sized pencil beams - beamlets

Pre-integrated over a finite beam area. Reduces time for super-position, assumes constant energy fluence over the beamlet area.

1cm 2 1.25MeV SSD=80cm

U Jelen, et al (2005) Phys Med Biol 50 , 1747-66.

Ostapiak, et al (1997) Med Phys 24 , 743-50.

Mainly for fast calculations in IMRT optimization. The beamlet sizes must match the resolution of the fluence grid.