FAST ALGORITHMS FOR COMPUTING AND DISPLAYING DOSE-DISTRIBUTIONS IN TOMOGRAM-ORIENTED BRACHY-RADIOTHERAPY

This paper describes in detail a dose calculation algorithm tailored t o the needs of tomogram-oriented brachyradiotherapy and a general-purp ose dose visualization for displaying the dose distribution as isoline s (or rather interval planes). The verbal description of the algorithm s is accompanied by structograms. However, the intention of the author s is to present very fast algorithms that are easy to implement and to give a ready-to-use example formulated in 68020 assembler code. Execu tion times are estimated theoretically by counting clock cycles and pr actically by measuring the execution time of sample calculations. It t urns out that both the dose calculation as well as the visualization a lgorithm need less than 1 s when applied to a radioactive point source lying on an arbitrary 320 x 256 grid of three-dimensional space.