Advanced Physics for Brachytherapy 2018

1. I need to be efficient

Implementation corrections:

• 1sc does not vary with θ within ΔΩ (Bθ, bθ constant along transport line) → Kernel tilting problem less important as E decreases → bθ evaluated recursively as a moving average of previous and current step 1sc generated per unit r is constant within the same voxel (scerma does not vary considerably within voxels) → Scerma gradient problem more important close to a source → in high scerma gradient regions scerma is estimated piecewise from a log-linear interpolation over r S • S

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