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Ray Tracing
In order to determine the radiological path d
radiol
through the
patient, one has to determine – voxel by voxel – the
segments d
1
, d
2
, .. in each single voxel.
segment d
i,j,k
voxel with index i,j,k
In a general formulation, the radiological path d
radiol
is:
The evaluation of this equation scales with the number of
voxels =
(for instance: 256 x 256 x 64 = 4 x10
6
iterations)
23
∑∑∑
⋅
=
k
kj, i,
kj, i,
j
i
radiol
μ d
μ
1
d
For photons:
k j
i
NNN
⋅ ⋅