Davidson Scott E, Popple Richard A, Ibbott Geoffrey S, Followill David S
Department of Radiation Physics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
Med Phys. 2008 Dec;35(12):5434-9. doi: 10.1118/1.3006353.
The purpose of this study was to determine the accuracy of five commonly used intensity-modulated radiation therapy (IMRT) treatment planning systems (TPSs), 3 using convolution superposition algorithms or the analytical anisotropic algorithm (CSA/AAAs) and 2 using pencil beam algorithms (PBAs), in calculating the absorbed dose within a low-density, heterogeneous region when compared with measurements made in an anthropomorphic thorax phantom. The dose predicted in the target center met the test criteria (5% of the dose normalization point or 3 mm distance to agreement) for all TPSs tested; however, at the tumor-lung interface and at the peripheral lung in the vicinity of the tumor, the CSA/AAAs performed better than the PBAs (85% and 50%, respectively, of pixels meeting the 5%/3-mm test criteria), and thus should be used to determine dose in heterogeneous regions.
本研究的目的是确定五种常用的调强放射治疗（IMRT）治疗计划系统（TPS）在计算低密度、非均匀区域内的吸收剂量时的准确性，其中3种使用卷积叠加算法或解析各向异性算法（CSA/AAA），2种使用笔形束算法（PBA），并与在人体胸部模型中进行的测量结果进行比较。在所有测试的TPS中，靶区中心预测的剂量均符合测试标准（剂量归一化点的5%或距离一致性为3 mm）；然而，在肿瘤-肺界面以及肿瘤附近的周边肺组织中，CSA/AAA的表现优于PBA（分别有85%和50%的像素符合5%/3-mm测试标准），因此应用于确定非均匀区域的剂量。
