Treatment planning with external beams. Introduction and historical overview

In this first of a series of articles on Radiation Treatment Planning based on the Basic Physics Symposium of the American Association of Physicists in Medicine at the 73rd Annual meeting of the RSNA, an attempt has been made to provide a broad overview of the process of designing an optimal radiation therapy regimen. The essentials of treatment planning have been identified and essential terms have been defined. Variables to be selected have been identified and constraints in choosing treatment plans have been noted. The effect of combining multiple beams to achieve the most advantageous distribution of radiation dose within the patient has been discussed and the vital importance of appropriate quality control has been emphasized. Future articles will consider specific aspects of this discipline in detail.