IMRT 2018
adapted from Woo and Cunningham 1990 (Med. Phys. 17(2))
Kernel-based methods: Rectilinear density rescaling of the kernel
) sr
r
)(
(
(
) ) () ,( , s r −
water
2
, Eh
sr E h sr
,
=
) ,(
s
rel
rel
water
‘Rectilinear’ rescaling with the mean relative density along the path between s and r:
this would be the kernel dose in a homogeneous medium: h water !
s
( ) s
) sr
1
(
sd
,
=
s r
rel
−
water
r
…and after rectilinear rescaling
→ The point kernel dose is dependent on location inside of inhomogeneous media (patient!) → efficient numerical dose calculation w. fast fourier transform not possible without further approximations
r
ESTRO IMRT course 2017 Dose Calculation in Static and Rotational IMRT Madrid April 13th, 2017
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