Selection of techniques for orthovoltage radiation therapy.

ABSTRACT

Selection of appropriate orthovoltage radiation techniques (peak kilovoltage plus total filtration) may be based on the following factors (a) central axis percent depth dose, (b) exposure rate, (c) sensitivity of backscatter factor to size of a blocked field, (d) differential bone energy absorption, (e) penumbra characteristics, and (f) field uniformity. An analysis of these factors as a function of beam quality (i.e. half-value layer) has been performed and a recommendation of a minimal number of techniques (consistent with widely available techniques) is presented.