Dose Course 2018_Flipping book

Radiant energy transport along a transport line

a r 

b r 

−

−

A

B

e

+

e

( ) , 





h r

=

2

Analytical raytrace of kernel exponential through a voxel constitutes a transport step of the radiant energy:

r

R

in

radiant energy contribution from the voxel considering intravoxel attenuation ( ) 2 1 e a k a   − + −

e a

− 

R

( )

=

R





out

in

R

attenuation of incoming energy

out

. R ) becomes the

Energy deposited inside the voxel (appr. a 

deposited dose

• Parameter a  . from kernel parameterization (water) is scaled to represent the voxel medium, k stems from incident beam energy release (coll KERMA and SCERMA) and medium

• Performed separately for primary and scatter dose

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