Dose Course 2018_Flipping book
calculation techniques:
interpolation scheme to save convolutions, example (primary dose):
1. Pre-calculate lateral dose distributions, D k
, for a selected set
of kernel parameters a z k
, where k =1..n
2. Runtime operations per calculation point: • Calculate radiological depth z ⇒ a z • Interpolate between lateral dose distributions, D k and D k+1
a a −
D
A
D
z
z
2
k
z
k+1
D S =
(1 ) q
q +
q
−
=
k
z
a
/ A a
/ A a
a a −
z
z
z
z
z
z
z
k
k
k
k
k
k
+
1
+
1
+
1
2
S
=
Inverse square factor
z
Two lateral distributions sufficient for primary dose and three for scatter dose. Only five convolutions per field!
This is the PK implementation in Oncentra
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