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Volume definition-summary
•
GTV-
demonstrable tumour
•
CTV
- GTV + subclinical tumour
•
PTV
- CTV + margin for
uncertainties (internal margin &
set-up margin)
•
TrV-
volume enclosed by
specified isodose
•
IrV-
tissue volume receiving dose
deemed significant in relation to
normal tissue tolerance
• OAR- critical structure
• PRV- planning organ at risk
volume
IrV
TrV
PTV
CTV
GTV