Dose Course 2018_Flipping book

Collimator leakage

MLC intraleaf and interleaf

1. Two effects: • Diffused dose from spiky interleaf fluence leakage • Intraleaf attenuation

Intraleaf leakage very small:

m   − 

t

0.0408 18.0 8.0 −  

e

→

e

=

0.28%

8 cm tungsten at 3 MeV

Measuements from Arnfield et al , 2000 Med. Phys. 27 p 2231-2241

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