Folie 1

Learning Objectives



To give an overview of margin concepts



Why do we use or need margins?



To provide a qualitative understanding of a margin recipe



To provide an overview of assumptions being made in the derivations of the van Herk

margin recipe



To discuss applicability of “conventional” margin concepts in hypo-fractionated / single fraction

SBRT



To discuss the effect of a limited number of fractions on random error



Explain why a random error for hypofractionated treatments results in a systematic

error



Explain how to calculate margins for single fraction and hypofractionated treatment

and provide some practical examples



How to add errors?



To discuss margins for tumors that move with respiration



To give suggestions for further reading