Quality assurance in dynamic radiotherapy techniques

Compared with conventional radiation treatment techniques, quality assurance for dynamic techniques has to consider additionally the variability of the movement parameters of the treatment unit. In this context the exactness and the reliability of the computer control are of special interest. In this paper the results of quality assurance for dynamic treatment techniques are reported. At first investigations concerning the reproducibility are carried out. Another test is the simulation of conventional moving beam techniques by external computer control. Further the differences between measured dose distributions of dynamic techniques and the distributions resulting from the sequence of fixed fields approximating these techniques are determined. Finally we compared measured and calculated dose distributions. The results of the investigations justify the introduction of dynamic radiation treatment techniques into clinical use.