[Sonographic location of the prostate gland by perineal-tomography (author's transl)].

The concept of radiation therapy of carcinoma of the prostate includes radiation of the primary tumour via a perineal field, besides ventral and dorsal irradiation fields. Therapy planning adapted to the individual anatomical conditions in the minor pelvis led to location of the prostate via perineal, sagittal ultrasonic tomography. Sonographic examination was conducted in 10 patients with carcinoma of the prostate, in 5 patients with benign enlargements of the organ and in 5 patients with urologically normal findings, taking the positioning of the patient during irradiation into consideration. In 18 of these 20 patients it was possible to determine the anatomical parameters relevant to therapeutic planning. Choice of the field dimensions, focal depth and angle of inclination of the central beam were greatly facilitated by this easy examination method which can be conducted as a routine measure.