ESTRO course Dose Modelling and Verification 2017

Origin of peripheral dose contributions: Head Scatter

Sources are all irradiated parts of the treatment head: main source the flattening filter Limited by the collimating devices Machine design dependent (FFF machines have less – approx 50%reduction Georg, Knoos, McClean MP 2011 )

10 [cm]

20

30°

IC

30 35

OC

45

100

Ahnesjö 1994 Med. Phys. 21 1227-35

5