FEASIBILITY SOLUTIONS IN RADIATION THERAPY TREATMENT PLANNING.

Radiation therapy treatment planning can be described as a two step-process which involves (1) the mapping from a physician-desired distribution of dose within a patient to an acceptable distribution for the weights of the possible rays through the patient and (2) the clinical implementation of that mapping. At present, both steps of RTP are done by specialists on the basis of experience, judgment, and trial and error. The authors describe a computer technique which determines step (1) of treatment planning. They obtain the weights for all possible rays through a patient by (1) determining the relative dose contribution of each of many sample rays from different gantry positions and locations within the beam, and by (2) iterating the relative contributions of the sample rays with physician-desired dose contours and constraints to find an acceptable weight for each ray.