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How a gEUD objective works
•
The parameter a is organ specific. It is related to the parameter n,
describing the volume effect in the Lyman – Kutcher – Burman
NTCP model as n = 1/a.
•
a = +∞ (high a values ): gEUD tends to the max dose- serial organs
•
a = 1
gEUD equals the mean dose - for
parallel organs
•
a = - ∞ (negative a values ): gEUD tends to the min dose- target min
dose
Weights of virtual dose-volume objectives
Serial organ
Parallel organ
Slide courtesy: Luca Cozzi, Varian Medical Systems
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