1202 / 1983
Margins for PTV
• Ideally, measure random and systematic error
•
calculate margins so that ≥99 % of CTV receives
≥95 % of prescribed dose
Adjustment of the PTV is not permitted
1C
Dose prescription and reporting follow ICRU standards 1B
“Old-fashion” RT
“High-precision” RT
Blocks = GTV + 2 cm CTV = GTV + 5-8 mm
PTV = CTV + mobility + planning + setup
Blocks = PTV + PENUMBRA