Course book Advanced Treatment Planning 2018

Choice of optimal beam energy

4MV 6MV 8MV

≥18MV

10MV

15MV

Aspects

Cranial

▪ penetration depth ▪ dose delivered to normal tissue ▪ penumbra broadening

HN

Thorax

Pelvic

Higher energy in low density regions

▪ higher energies means larger penumbra due to increase in lateral electron transport (≥10MV) ▪ sufficiently accurate planning calculation algorithms are required for decisions on optimal beam energy