Abstract Objective To compare the accuracy of enhanced dynamic wedge (EDW) models of adaptive convolution algorithm (ACA) in Pinnacle3 9.0 and anisotropic analytical algorithm (AAA),and pencil beam convolution (PBC) algorithms in Eclipse7.3 treatment planning systems (TPS). Methods To evaluate the accuracy of the three algorithm models, we compared actual measurement values with TPS calculation values of EDW wedge factors under for different fields in which Varian-21EX 6 MV X-ray was applied, and also compared the actual dose distribution profile with that of TPS. Results The deviations of EDW wedge factors of symmetry fields and asymmetric fields are within 2.8% and 19.4% for ACA in Pinnacle3 9.0. Meanwhile, the deviations are 1.0% and 2.0% for AAA, 1.2% and 3.0% for PBC in Eclipse7.3. The deviations between measurement and calculation of all fields′ profile for ACA is within 3% and within 2.7% for AAA within 4.0% for PBC in wedge direction. For the dose distributions, we evaluated the pass rates of three algorithms using gamma analysis. The gamma pass rates among all the three algorithms in symmetry and asymmetric fields are above 87% and 85% respectively. After the removal of the penumbra zone, the pass rates among all the three algorithms are above 96% in symmetry fields, and above 95% in asymmetric fields, respectively. Conclusions AAA and PBC algorithms in symmetric and asymmetric fields can meet the need of clinical applications. While, wedge factor of ACA should not be used in clinical due to its greater error in asymmetric fields.
XING Xiao-fen,CUI Tong,ZHENG Xu-liang et al. Accuracy comparison of enhanced dynamic wedge modles among Pinnacle3 9.0 ACA and Eclipse7.3 AAA,PBC algorithm[J]. Chinese Journal of Radiation Oncology, 2012, 21(5): 468-470.
XING Xiao-fen,CUI Tong,ZHENG Xu-liang et al. Accuracy comparison of enhanced dynamic wedge modles among Pinnacle3 9.0 ACA and Eclipse7.3 AAA,PBC algorithm[J]. Chinese Journal of Radiation Oncology, 2012, 21(5): 468-470.
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2012, Vol. 21 
