An investigation into the penumbral dose of a bloxel, (block element) matrix-design block to replace currently utilized radiation treatment field shaping techniques

Presented here is an investigation to establish physical rationale for the acceptance by physicians of a new form of blocking device for radiotherapy. The focus of the investigation is on the percent dosage obtained in the penumbral regions created by 6 mm and 9 mm stepped-edge blocks, relative to a straight edge, when exposed to 1.25 and 18 MeV photons