2646-2647 / 2953
Kernel-based methods:
Rectilinear density rescaling of the kernel
s
‘Rectilinear’ rescaling with the
mean
relative density
along the path
between s and r:
( )
( )
′
s
s
r
r
r
rr
ρ
1
(
)
(
)
)
() ,( ,
) ,(
)(
, ,
2
s r sr
E h sr
r
srEh
rel
water
rel
water
r r rr
rr
r
rr
− ⋅
⋅
⋅
=
ρ
ρ
ρ
ρ
this would be the
kernel dose in a
adapted from Woo and
Cunningham 1990
(Med. Phys. 17(2))
ESTRO IMRT course 2016
Dose Calculation in Static and Rotational IMRT
London April 7th, 2016
-31-
r
∫
′
−
=
r
water
rel
sd
s r
sr
r
r r
ρ
ρ
,
→
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
homogeneous
medium: h
water
!
…and after
rectilinear
rescaling