ABSTRACT -- The position of radioisotope source in a patient who was treated by radioisotope insertion technique is very important for calculate a dose distribution. The Inputting from keyboard or digitizer is good practice for source positioning but not enough for source to organ relationship in a patient. Inputting source position on the computer screen together with x-ray imaging will be done easier and can be seen the source to organ relationship that very helpful in reducing of inputting error. An error may be rise from a measurement on the film by using ruler or the film slid while using the digitizer. The inputting on screen will produce an error less than 0.3 mm. (depend on the screen resolution). The x-ray imaging can be improved the quality by adjust a contrast, brightness, Zoom in/out and Pan the image on the screen. It can be show the relationship line between the antero-posterior image with respect to the lateral image as well.

KEYWORDS -- radioisotope source position, radioisotope insertion