TVD 2016

Target volumes – OARs + PRVs

• Uncertainties apply to the OAR … so a ‘PTV margin’ can be  added around it ‐ to give the Planning organ at Risk Volume  (PRV)

• But … the use of this technique will substantially increase the  l f l vo ume o norma structures

• May be smaller than PTV margin Component for systematic error can often be smaller