IMRT 2018

Gamma analysis physically relevant?

What do we want to detect with patient-specific QA? • Do we have confidence in our MLCs? – Perhaps better addressed with machine QA – Thorough commissioning of IMRT with challenging plans and several measurement systems – Constancy checks with challenging plan • Do we have confidence in our dose-calculation algorithm? – Aware of limitations – Impact depends strongly on the individual plan – The gamma index seems to correlate with plan complexity/modulation – Gamma pass-rates can probably highlight challenging cases

06/06/2018