Recent findings in gamma analysis, an evaluation method for radiotherapy plan verification

An outline of currently available 3D dosimetry systems in combination with 3D gamma analysis and back-projection of the measured doses in patient CT images is presented. Certain aspects of 2D planar dosimetry and 2D gamma analysis that are not evident at first glance are also described, and alternatives that are only at the research stage, such as Cherenkov radiation measurement, are mentioned. Gamma analysis can be a reliable tool if used with adequate caution. Current practice in the Czech Republic gets slowly behind the standards in other countries. (orig.)