Abstract
A commercialized implementation of linear Boltzmann transport equation solver, the Acuros XB algorithm (AXB), represents a class of most advanced type ‘c’ photon radiotherapy dose calculation algorithms. The purpose of the study was to quantify the effects of the modifications implemented in the more recent version 11 of the AXB (AXB11) compared to the first commercial implementation, version 10 of the AXB (AXB10), in various anatomical regions in clinical treatment planning. Both versions of the AXB were part of Varian's Eclipse clinical treatment planning system and treatment plans for 10 patients were created using intensity‐modulated radiotherapy (IMRT) and volumetric‐modulated arc radiotherapy (VMAT). The plans were first created with the AXB10 and then recalculated with the AXB11 and full Monte Carlo (MC) simulations. Considering the full MC simulations as reference, a DVH analysis for gross tumor and planning target volumes (GTV and PTV) and organs at risk was performed, and also 3D gamma agreement index (GAI) values within a 15% isodose region and for the PTV were determined. Although differences up to 12% in DVH analysis were seen between the MC simulations and the AXB, based on the results of this study no general conclusion can be drawn that the modifications made in the AXB11 compared to the AXB10 would imply that the dose calculation accuracy of the AXB10 would be inferior to the AXB11 in the clinical patient treatment planning. The only clear improvement with the AXB11 over the AXB10 is the dose calculation accuracy in air cavities. In general, no large deviations are present in the DVH analysis results between the two versions of the algorithm, and the results of 3D gamma analysis do not favor one or the other. Thus it may be concluded that the results of the comprehensive studies assessing the accuracy of the AXB10 may be extended to the AXB11.PACS numbers: 87.55.‐x, 87.55.D‐, 87.55.K‐, 87.55.kd, 87.55.Qr
Highlights
214 Ojala et al.: Dose differences between two Acuros XB (AXB) versions since the other sources of the total uncertainty were estimated to decrease
In this study, using full Monte Carlo (MC) simulations as the reference, the effect of the modifications made in the AXB11 compared to the AXB10 on the dose calculation accuracy in the clinical patient treatment planning was assessed
No general conclusion can be made that the dose calculation accuracy of the AXB10 would be inferior to the AXB11, except in air cavities
Summary
214 Ojala et al.: Dose differences between two AXB versions since the other sources of the total uncertainty were estimated to decrease. Type ‘a’, correction-based algorithms, based on measurements and corrected to account for patient contours and tissue heterogeneities, are replaced by type ‘b’, model-based algorithms. Type ‘b’ algorithms apply various superposition and convolution techniques to provide increased accuracy over type ‘a’ algorithms, especially in the presence of tissue heterogeneities. Type ‘c’ algorithms represent the most recent class of dose calculation algorithms which 1) have improved modeling of secondary electron transport essential for accurate heterogeneity correction, when compared to type ‘b’ algorithms; 2) are able to calculate the dose deposition, in addition to all biological tissues, in the presence of high-Z implanted materials; and 3) are able to report the dose as dose to medium.[4,5]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
