[Conceptions for optimization in radiation therapy (author's transl)]

The discrepancy between the exact radiation planning possible nowadays and the distinctly differing real dose to the target volume is interpreted as due to the appearance of unavoidable time-dependent disturbance variables which are not quantitatively predictable. By means of the block diagram generally used in control engineering is shown the necessity of introducing a feedback mechanism with small time-lag in order to eliminate the disturbance variables. A practicable plan of such a control system for application in therapeutic radiology is outlined.