<> "The repository administrator has not yet configured an RDF license."^^ . <> . . "Risk-adapted Optimization in Intensity Modulated Proton Therapy (IMPT)"^^ . "Due to the pronounced dose gradients generated by proton beams, proton treatment plans can be very sensitive to treatment uncertainties. However in IMPT many different solutions of the inverse problem exist which result in dose distributions of comparable quality. This thesis investigates methods to exploit this degeneracy of solutions to generate treatment plans which are robust to uncertainties. An investigation of the optimization algorithm in the used IMPT software KonRad revealed that the standard optimization algorithm is not capable to find the optimal treatment plan in a reasonable time. Thus several additional optimization algorithms were implemented and tested in KonRad. The best results were achieved using the L-BFGS algorithm. To rate the sensitivity to uncertainties of individual beamlet dose distributions the heterogeneity number H was developed. It was shown that H correlates with the dose calculation error introduced by the commonly employed pencil beam algorithm as well as with the sensitivity to setup errors of individual beamlets. Finally, the \"worst case optimization\" was developed to account for uncertainties during the inverse treatment planning. This technique was applied to account for range uncertainties, setup errors and a combination of both uncertainties. The treatment plans generated with this new method are much more robust to the respective uncertainties as conventional IMPT and even as conventional single-field proton plans."^^ . "2008" . . . . . . . . "Daniel"^^ . "Pflugfelder"^^ . "Daniel Pflugfelder"^^ . . . . . . "Risk-adapted Optimization in Intensity Modulated Proton Therapy (IMPT) (PDF)"^^ . . . "pflugfelder.pdf"^^ . . . "Risk-adapted Optimization in Intensity Modulated Proton Therapy (IMPT) (Other)"^^ . . . . . . "indexcodes.txt"^^ . . . "Risk-adapted Optimization in Intensity Modulated Proton Therapy (IMPT) (Other)"^^ . . . . . . "lightbox.jpg"^^ . . . "Risk-adapted Optimization in Intensity Modulated Proton Therapy (IMPT) (Other)"^^ . . . . . . "preview.jpg"^^ . . . "Risk-adapted Optimization in Intensity Modulated Proton Therapy (IMPT) (Other)"^^ . . . . . . "medium.jpg"^^ . . . "Risk-adapted Optimization in Intensity Modulated Proton Therapy (IMPT) (Other)"^^ . . . . . . "small.jpg"^^ . . "HTML Summary of #8115 \n\nRisk-adapted Optimization in Intensity Modulated Proton Therapy (IMPT)\n\n" . "text/html" . . . "530 Physik"@de . "530 Physics"@en . .