Print Email Facebook Twitter Fast and accurate sensitivity analysis of IMPT treatment plans using Polynomial Chaos Expansion Title Fast and accurate sensitivity analysis of IMPT treatment plans using Polynomial Chaos Expansion Author Perko, Z. (TU Delft RST/Reactor Physics and Nuclear Materials) van der Voort, S.R. (TU Delft Applied Sciences; Erasmus MC) Van De Water, Steven (Erasmus MC) Hartman, C.M.H. (TU Delft ImPhys/Practicum support; Erasmus MC) Hoogeman, M.S. (Erasmus MC) Lathouwers, D. (TU Delft RST/Reactor Physics and Nuclear Materials) Faculty Applied Sciences Date 2016 Abstract The highly conformal planned dose distribution achievable in intensity modulated proton therapy (IMPT) can severely be compromised by uncertainties in patient setup and proton range. While several robust optimization approaches have been presented to address this issue, appropriate methods to accurately estimate the robustness of treatment plans are still lacking. To fill this gap we present Polynomial Chaos Expansion (PCE) techniques which are easily applicable and create a meta-model of the dose engine by approximating the dose in every voxel with multidimensional polynomials. This Polynomial Chaos (PC) model can be built in an automated fashion relatively cheaply and subsequently it can be used to perform comprehensive robustness analysis. We adapted PC to provide among others the expected dose, the dose variance, accurate probability distribution of dose-volume histogram (DVH) metrics (e.g. minimum tumor or maximum organ dose), exact bandwidths of DVHs, and to separate the effects of random and systematic errors. We present the outcome of our verification experiments based on 6 head-and-neck (HN) patients, and exemplify the usefulness of PCE by comparing a robust and a non-robust treatment plan for a selected HN case. The results suggest that PCE is highly valuable for both research and clinical applications. Subject Polynomial Chaosproton therapyRange errorRobust optimizationSensitivitySetup errorUncertainty To reference this document use: http://resolver.tudelft.nl/uuid:b8fc4d46-e0f6-49ec-8eb2-d01176e8393a DOI https://doi.org/10.1088/0031-9155/61/12/4646 Embargo date 2017-05-26 ISSN 0031-9155 Source Physics in Medicine and Biology, 61 (12), 4646-4664 Part of collection Institutional Repository Document type journal article Rights © 2016 Z. Perko, S.R. van der Voort, Steven Van De Water, C.M.H. Hartman, M.S. Hoogeman, D. Lathouwers Files PDF Fast_and_Accurate_Sensiti ... PCE.._.pdf 1.42 MB Close viewer /islandora/object/uuid:b8fc4d46-e0f6-49ec-8eb2-d01176e8393a/datastream/OBJ/view