The Physics of Radiosurgery.

Abstract

Stereotactic radiosurgery was introduced more than 40 years ago as a way of treating various intracranial lesions without recourse to open-skull surgery. Since then, it has been extended both in terms of the radiation modalities that have been used and the types of lesions treated. Each radiation modality has its own physical characteristics and limitations which have to be considered when planning and delivering the treatment. Comparisons of dose distributions that can be achieved with reasonable effort indicate domains of applicability where each modality might play a larger role. Recent developments in treatment planning capabilities, noninvasive immobilization, and beam delivery hold the promise to extend the techniques of radiosurgery to fractionated, precision radiotherapy which might permit the treatment of larger intracranial lesions and possibly point the way to stereotactic treatments outside the head.