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1 I need to be efficient angular discretization
.
,
•
discretization artifacts or “rays”: an artificial buildup of particle fluence along the finite
b f d
d
num er o irections use
with high gradients of scatter fluence, at points where primary dose is small
with N & voxel size at the expense of calculation time and potential volume
directions
averaging
10
10
10
4
6
8
4.5 %
4
6
8
4
6
8
224
360
528
0
2
1.5 %
2.5 %
3.5 %
0
2
0
2
ng, cm
-4
-2
-1.5 %
-0.5 %
0.5 %
-4
-2
-4
-2
Alo
-8
-6
-2.5 %
-8
-6
-8
-6
Figure from: Venselaar Baltas Meigooni
3 4 5 6 7 8 9 10
Away, cm
-10
3 4 5 6 7 8 9 10
Away, cm
-10
3 4 5 6 7 8 9 10
Away, cm
-10
,
,
,
Hoskin (Eds), Comprehensive Brachytehrapy:
physical and clinical aspects. CRC Press,
Taylor & Francis, © 2013