Grid based Boltzman solvers (GBBS) based
models
1
❑
Transport
o
Primary photons are ray-traced in the medium
o
Scattered photon fluence and the final electron fluence in calculated for
each voxel where tissue type and density is known
❑
Deposit
o
From the differential electron fluence one can apply either stopping
electronic power for the medium or water to receive the absorbed dose
o
Only a biological material can be assigned: lung, adipose tissue, muscle,
cartilage, or bone.
o
The material corresponding to a given HU is hard-coded into a lookup
table..
❑
We have either or
Dublin 2018
10
,
1)
Only one system available for radiotherapy – Acuros from Varian
,