en Radiation Biology Radiation Biology گزارش کوتاه Short Report <p>Background: Dose calculation algorithms play a very important role in predicting the explicit dose distribution. We evaluated the percent depth dose (PDD), lateral depth dose profile, and surface dose volume histogram in inhomogeneous media using calculation algorithms and inhomogeneity correction methods. Materials and Methods: The homogeneous and inhomogeneous virtual slab phantoms used in this study were manufactured in the radiation treatment planning system to represent the air, lung, and bone density with planned radiation treatment of 6 MV photons, a field size of 10 &times; 10 cm², and a source-to-surface distance of 100 cm. Results: The PDD of air density slab for the Acuros XB (AXB) algorithm was differed by an average of 20% in comparison with other algorithms. Rebuild up occurred in the region below the air density slab (10&ndash;10.6 cm) for the AXB algorithm. The lateral dose profiles for the air density slab showed relatively large differences (over 30%) in the field. There were large differences (20.0%&ndash;26.1%) at the second homogeneous&ndash;inhomogeneous junction (depth of 10 cm) in the field for all calculation methods. The surface dose volume histogram for the pencil beam algorithm showed a response that was approximately 4% lower than that for the AXB algorithm. Conclusion: The dose calculation uncertainties were shown to change at the interface between different densities and in varied densities using the dose calculation methods. In particular, the AXB algorithm showed large differences in and out of the field in inhomogeneous media.</p> <p></p> Keywords: Inhomogeneous media, calculation algorithms, correction methods, PDD, dose profiles. 269 278 http://ijrr.com/browse.php?a_code=A-10-1-629&slc_lang=en&sid=1 Y.L. Kim 790031947532846009945 790031947532846009945 No Department of Radiology, Choonhae College of Health Science, Ulsan 689-784, South Korea T.S. Suh 790031947532846009946 790031947532846009946 Yes Department of Radiology, Choonhae College of Health Science, Ulsan 689-784, South Korea B.Y. Choe 790031947532846009947 790031947532846009947 No Department of Radiology, Choonhae College of Health Science, Ulsan 689-784, South Korea B.O. Choi 790031947532846009948 790031947532846009948 No Department of Radiation Oncology, Seoul St. Mary’s Hospital, The Catholic University, Seoul 137-701, South Korea J.B. Chung 790031947532846009949 790031947532846009949 No Department of Radiadion Oncology, Seoul National University Bundang Hospital, Seongnam 463-707, South Korea J.W. Lee 790031947532846009950 790031947532846009950 No Department of Radiation Oncology, Konkuk University Medical Center, Seoul 143-729, South Korea Y.K. Bae 790031947532846009951 790031947532846009951 No Department of Radiation Oncology, Konkuk University Medical Center, Seoul 143-729, South Korea B.M. Park 790031947532846009952 790031947532846009952 No Department of Radiation Oncology, Konkuk University Medical Center, Seoul 143-729, South Korea J.Y. Jung 790031947532846009953 790031947532846009953 No Department of Radiation Oncology, Inje University Sanggye Paik Hospital, Seoul 139-707, South Korea Y.J. Shin 790031947532846009954 790031947532846009954 No Department of Radiation Oncology, Inje University Sanggye Paik Hospital, Seoul 139-707, South Korea