IMRT Course 2016

Kernel-based methods: Convolution/Superposition

Simplest possible situation: Monoenergetic incident photons, Homogeneous medium

Dose in point r…

∫

( ) r

( ) (

)

3

s rhsTsd rD r r r

=

−

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 2016 Dose Calculation in Static and Rotational IMRT London April 7th, 2016

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