Electron dose distributions in an anthropomorphic phantom--verification of Theraplan treatment planning algorithm

As part of a Quality Assurance program, the performance of Theraplan (Version 4.0) for electron beam calculations was checked versus experiments carried out with an anthropomorphic (Rando) phantom. Large disagreements (up to 40%) between measured and calculated dose distributions were discovered which could not be explained in terms of the assumptions inherent in the code. Analysis of this data has led to discovery of an error in the software. AECL is working at present on a new software version with this error corrected.