[Mantle irradiation with 18 MeV photons. Measurement and calculation of dose distribution].

Dose distribution in mantle fields irradiated with 18 MeV photons has been studied in an Alderson-Rando phantom with thermoluminescent dosimeters. The treatment was also simulated on an RT-plan 7000 computer; calculated and measured doses in anatomical sites of major interest were compared. Doses in all significant points were within +/- 7% of the doses at the reference point. Calculated and measured doses agreed within +/- 5% except points situated near unhomogeneous tissues. The authors discuss their results and present conclusions about algorithms for computer dose calculation in irregular field treatments.