Figure 1.

(a) Set-up of aSi1000 EPID for acquisition fluence maps of IMRT plan AP fields with 4.2 cm water equivalent additional build-up in SED = 97 cm(guard cover of EPID separated).(b) Set-up of 2D Array Seven29^TM for acquisition 2D-dose map of IMRT plan AP fields with 4.4 cm water equivalent additional build-up and 5.0 cm thick backscatter material (reference point of measurement was then located at 100 cm from the radiation source)$.$ 2D,two-dimensional; AP, anteroposterior; EPID, electronicportal imaging device; IMRT, intensity modulated radiotherapy; SED, source EPIDdistance.