Image guided radiotherapy

Abstract

Image guided radiation therapy (IGRT) is currently one of the most active research fields in medical physics. The recent development of high precision dose delivery techniques with high energy photon and hadron beams can only be fully exploited if we confidently know the shape and location of radiation targets and the organs at risk at the time of the treatment. Most of the time, anatomical images of the patient were only acquired for the purpose of diagnosis and treatment planning usually days before the treatment planning process, i.e., the patient anatomy was assumed to be static in time. As a result, all time dependent variations of relevant anatomical structures, like shifts and deformations of tissues in time, for instance also caused by the radiation treatment, were not accounted for and therefore are a significant source of potential treatment errors. We briefly describe the basic concepts and technology employed in current IGRT practice. © 2009 Springer Science + Business Media B.V.