THEORETICAL AND EXPERIMENTAL INVESTIGATIONS OF A NEWLY DEVELOPED INTRACAVITARY APPLICATOR SYSTEM FOR THE RADIOTHERMOTHERAPY OF GYNECOLOGICAL TUMORS

This paper describes a new type of applicator system for the intracavi tary radiothermotherapy of gynaecological tumours. Hyperthermia and ra diation can be delivered by one and the same applicator. The hyperther mia is delivered by a modified capacitive heating technique (27.12 MHz ) combined with cooling systems, the radiation by the numerically cont rolled oscillation of a gamma source on the inside of the main applica tor, the RF gamma applicator (HDR afterloading technique). Isotherms a nd isodoses can be adapted to the anatomical-pathological situation. I nteractions between the applicator system and the surrounding tissue w ere investigated in a theoretical model (FEM). Complex two-dimensional SAR calculations as well as three-dimensional temperature calculation s were carried out. The RF gamma applicator was also examined by therm ography; the thermography proved the theoretical modelling to be corre ct. The applicators were also tested in animal experiments.