Experimental evaluation of the accuracy of skin dose calculation for a commercial treatment planning system

The present work uses the Eclipse treatment planning system (TPS) to investigate the accuracy of skin dose calculations. Micro‐MOSFETs (metal oxide semiconductor field effect transistors) were used to measure skin dose for a range of irradiation conditions (open fields, physical wedges, dynamic wedges, various source‐to‐surface distances) for 6‐MV and 10‐MV beams, and the results were compared with the calculated mean dose to a “skin” structure 2 mm thick for semi‐cylindrical phantoms (representative of a neck or breast). Agreement between the calculated and measured skin dose values was better than ±20% for 95% of all measured points (6‐MV and 10‐MV X‐ray spectra alike). For a fixed geometry, the TPS correctly calculated relative changes in dose, showing that minimization of skin dose in intensity‐modulated radiation therapy will be effective in Eclipse. PACS numbers: 87.53.Bn, 87.53.Dq, 87.66.Pm, 87.66.Xa

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