Physics Bucharest 2017

MU examples

Treat 2 GY to the centre of a volume ||pair The Field size is 20*20cm 2 Patient separation is 18 cm Treat with SSD= 100 cm, 10 MV Use the Depth dose chart: PDD*output(9 cm, 20)=80.9cGy/100MU Dose from each field is 1 Gy

To deliver 1Gy : 100cGy/80.9(cGy/100MU)*100 = 123.6 MU ie 124 MU from each beam