IMRT

Kernel-based methods: Convolution/Superposition

Simplest possible situation: Monoenergetic incident photons, Homogeneous medium

Dose in point r…

( ) 

) s rhsTsd rD   

( ) (

∫

3

=

−

primary photon source

… superposition of all point kernels originating around all possible points s

mathematically: 3D- convolution integral

→ very efficient numerical implementation via fast fourier transform! BUT necessary condition: point kernel independent of location (homogeneous medium)

s

r

ESTRO IMRT course 2015 Dose Calculation in Static and Rotational IMRT Brussels October 8th, 2015

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