Fig. 1.

A) The CT slice of a NMSC patient with CTV and OARs contoured. A 3 cm layer of air, shown in cyan, was added externally with a mass density of 0.001 g/ml, while 0 cm bolus was considered. B-J) The same CT slice, with an addition of bolus with varying thicknesses from 0.25 to 5 cm. This electronic bolus, shown in orange, was considered as water with a mass density of 1 g/ml