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Model based dose calculations
Energy fluence engine,
multisource
models
•
Finite photon source size
•
Open fluence distribution
•
Fluence modulation
– Step&shot
– Dynamic
– Wedges
•
Head scatter sources
– flattening filter
– collimators
– wedges
•
Back scatter from
collimators to monitor
•
Collimator leakage
, including
– MLC interleaf leakage
– shape of MLC leaf ends
•
Beam spectra
•
Spectral changes
•
Electron contamination
Treatment
head
processes
to model