Dose Course 2018_Flipping book

Photon dose calculation methods Dose engines

Method characteristics

Remarks

Monte Carlo

Explicit particle transport simulation + Accurate - Noisy dose distributions Solves numerically transport equtations + Accurate - Discretization effects Implicit particle transport + Accurate - Minor systematic errors

Standard research tool, clinical use under development

Analytic solvers

Standard tool in nuclear engineering, less common in medical physics Current workhorse for accurate calculations in lung. The workhorse for many applications, in particular IMRT optimization. Often used for factorbased calculation schemes Can be used to correct dose calculated with any method for a homogeneous case

”Model based”

Point kernel methods “Convolution/superposition” “Collapsed Cone”

Pencil kernel methods

Heterogeneity impact through corrections

Scatter dose estimations

”Semi” pencil kernel metods

“Factor based”

1D heterogeneity corrections

Models what happen along the incident beam direction only

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