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Errors in the radiotherapy chain
(McKenzie et al., BIR 2003)
•
Systematic errors
:
treatment preparation errors
Delineation errors
Organ position and shape at time of localization
Phantom transfer errors
o
Geometric imaging error (e.g. CT alignment laser errors)
o
Treatment planning system error (e.g. shielding blocks)
o
Linear accelerator geometry error (e.g. laser & coll. position)
Set-up error at time of localization
TPS beam algorithm error
Breathing positional error
•
Random errors
:
treatment execution errors
Organ position and shape
Daily set-up error