Total body irradiation with a moving beam

In a usual radiotherapy room, it is not ready to obtain a sufficiently large field for total body irradiation. Therefore, a technique for TBI with a moving beam is developed by a little improvement of a software concerning a control system of beam output without any reconstruction on 10 MV linear accelerator. A large field enough for TBI is obtained by rotating the beam with a pendulum angles of 60 degrees for each sides against vertical axis. Correction factors at every one degree for an adjustment of beam output by changing Gy/degree are calculated. The dose uniformity is better than ± 3 % over a long axis of 200 cm. (author)