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Convention problem: dose
medium
dose
cell nucleus in medium
dose
water
!!
w
en,w
w,w
0
e
z
D
m
m
−
=
m
en,m
w
w,m
0
m
e
z
D
s
m
m
−
=
Reference dosimetry: dose to a small water element
w
embedded at depth
z
in a large water phantom:
Often considered as a surrogate for nucleus dose
The way different TPS does it
Hence, full conversion from small water element in water
to small water element in medium:
m
en,m
m,m
0
e
z
D
m
m
−
=
“Monte Carlo dose” can be implemented as dose to
medium in medium:
approx. eqs:
Bragg Gray cavity conversion (simple in Monte Carlo)!!
w
w,m
m,m m
D
D s
=
m
w
en,m w
w,m
m
w,w
en,w
e
e
z
z
D s
D
m
m
m
m
−
−
=
This talk....
Dublin 2018
4
From Anders Ahnesjö