TOTAL-BODY IRRADIATION ON AN ISOCENTRIC LINEAR-ACCELERATOR - A RADIATION OUTPUT COMPENSATION TECHNIQUE

A treatment technique for total-body irradiation (TBI) is proposed tha t combines arc therapy with dynamic output control to achieve high-gra de dose uniformity. The patient lies on a low couch and receives expos ure in the prone and supine positions from a modulated arcing beam. Th e technique has been validated using a personal computer to control th e linear accelerator and we demonstrate that only minor alterations to current dynamic therapy systems would be required. We have examined t he practical application of this treatment with emphasis on methods of conformal therapy where an optimized dose distribution is prepared fr om a matrix of caliper measurements taken from the patient. This techn ique provides a means for regular TBI treatment on a computer-controll ed linear accelerator that is easy to set up, requires short exposure times and is comfortable for the patient.