Dose Course 2018_Flipping book

Model based dose calculations Energy fluence engine, multisource models

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Finite photon source size

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Open fluence distribution

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Fluence modulation – Step&shot

– Dynamic – Wedges

Treatment head processes to model

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Head scatter sources – flattening filter – collimators – wedges

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Back scatter from collimators to monitor

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Collimator leakage , including – MLC interleaf leakage – shape of MLC leaf ends

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Beam spectra

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Spectral changes

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Electron contamination

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