A new type of equipment for transrectal ultrasonotomography was described in a previous paper. This equipment was evaluated from the data obtained from 205 cases in which examinations were performed. Tomograms were successfully recorded in 94% of cases. Tomograms sufficiently useful for diagnosis and the measurement of organs were obtained in 89% of cases for the prostate, 78% for the urinary bladder, and 80% for the seminal vesicles. No basic problems in the procedure were found, although hypotension of unknown origin was observed during the examination in a few cases.