IMRT 2018
Kernel-based methods: ‘Collapsed Cone’ approximation for efficient density rescaling
Further ‘smart’ approximations for efficient numerical implementation:
separate treatment of deposited primary energy and deposited phantom scattered dose further approximations for polyenergetic photon beams (details depend on implementation): Energy- averaged TERMA and point kernel; approximate or no modelling of beam hardening; …
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primary photons
scattered primary photons
primary charged particles
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charged particles from scattered prim. photons Direct beam phantom scatter dose
deposited primary energy deposited primary energy
Primary dose
Bremsstrahlung and annihilation photons
deposited scatter energy deposited scatter energy
charged particles from Bremsstrahlung and annihilation photons
Bremsstrahlung and annihilation energy deposited Bre sstrahlung and annihilation energy deposited
More details: Ahnesjö and Aspradakis 1999 (PMB 44(11))
ESTRO IMRT course 2017 Dose Calculation in Static and Rotational IMRT Madrid April 13th, 2017
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