5
Photon dose calculation methods
Dose engines
Method characteristics
Remarks
Monte Carlo
Explicit particle transport
simulation
+ Accurate
- Noisy dose distributions
Standard research tool,
clinical use under
development
Analytic solvers
Solves numerically transport
equtations
+ Accurate
- Discretization effects
Standard tool in nuclear
engineering, less
common in medical
physics
Point kernel methods
“Convolution/superposition”
“Collapsed Cone”
Implicit particle transport
+ Accurate
- Minor systematic errors
Current workhorse for
accurate calculations in
lung.
Pencil kernel methods
Heterogeneity impact through
corrections
The workhorse for many
applications, in particular
IMRT optimization.
Scatter dose estimations
”Semi” pencil kernel metods
Often used for
factorbased calculation
schemes
1D heterogeneity corrections
Models what happen along the
incident beam direction only
Can be used to correct
dose calculated with any
method for a
homogeneous case
”Model
based”
“Factor
based”