Ein Konzept zur Optimierung der Strahlentherapie

DSpace Repository

Show simple item record

dc.contributor.advisor Nüsslin, Fridtjof de_DE
dc.contributor.author Alber, Markus de_DE
dc.date.accessioned 2001-02-19 de_DE
dc.date.accessioned 2014-03-18T10:08:40Z
dc.date.available 2001-02-19 de_DE
dc.date.available 2014-03-18T10:08:40Z
dc.date.issued 2000 de_DE
dc.identifier.other 08988924X de_DE
dc.identifier.uri http://nbn-resolving.de/urn:nbn:de:bsz:21-opus-2212 de_DE
dc.identifier.uri http://hdl.handle.net/10900/48145
dc.description.abstract A method for the optimisation of intensity modulated radiotherapy (IMRT) with an emphasis on clinical and biological aspects is presented. Various models for the probability of cell survival as a function of single fraction and total dose form the objective function for the tumour tissue, which is to be minimized. The biological dose-response in normal tissues at micro-, meso- and macroscopic length scales represent constraints to the optimum. Both objective function and constraints are functionals of the dose distribution which can be reduced to effect densities by a mean-field approximation. The total effect is the integral of these densities over the organ volume. The optimum dose in the target volume results as the maximum under strict adherence to the normal tissue constraints. The fluence profiles are subject to a smoothing operation which ensures treatment efficiency. The constrained variational problem can be reduced to a finite optimisation problem by introducing a basis in fluence space. A phenomenological dose computation algorithm is presented which is designed for this fluence basis. This algorithm is merged with a Monte Carlo dose computation algorithm to form a hybrid which is capable of computations on clinical time scales. The combination of IMRT and Monte Carlo makes it possible to compensate for electron scatter effects at surfaces by modulating the primary fluence. The present concept explores the potential of IMRT for better chances for cure, which is demonstrated with a number of clinical examples. de_DE
dc.description.abstract A method for the optimisation of intensity modulated radiotherapy (IMRT) with an emphasis on clinical and biological aspects is presented. Various models for the probability of cell survival as a function of single fraction and total dose form the objective function for the tumour tissue, which is to be minimized. The biological dose-response in normal tissues at micro-, meso- and macroscopic length scales represent constraints to the optimum. Both objective function and constraints are functionals of the dose distribution which can be reduced to effect densities by a mean-field approximation. The total effect is the integral of these densities over the organ volume. The optimum dose in the target volume results as the maximum under strict adherence to the normal tissue constraints. The fluence profiles are subject to a smoothing operation which ensures treatment efficiency. The constrained variational problem can be reduced to a finite optimisation problem by introducing a basis in fluence space. A phenomenological dose computation algorithm is presented which is designed for this fluence basis. This algorithm is merged with a Monte Carlo dose computation algorithm to form a hybrid which is capable of computations on clinical time scales. The combination of IMRT and Monte Carlo makes it possible to compensate for electron scatter effects at surfaces by modulating the primary fluence. The present concept explores the potential of IMRT for better chances for cure, which is demonstrated with a number of clinical examples. en
dc.language.iso de de_DE
dc.publisher Universität Tübingen de_DE
dc.rights ubt-podno de_DE
dc.rights.uri http://tobias-lib.uni-tuebingen.de/doku/lic_ohne_pod.php?la=de de_DE
dc.rights.uri http://tobias-lib.uni-tuebingen.de/doku/lic_ohne_pod.php?la=en en
dc.subject.classification Strahlentherapie , Optimierung de_DE
dc.subject.ddc 610 de_DE
dc.subject.other IMRT , Monte Carlo Dosisberechnung de_DE
dc.subject.other IMRT , Monte Carlo dose computation , Radiotherapy , Optimisation en
dc.title Ein Konzept zur Optimierung der Strahlentherapie de_DE
dc.title A Concept for the Optimization of Radiotherapy en
dc.type Dissertation de_DE
dc.date.updated 2005-02-22 de_DE
dcterms.dateAccepted 2000-10-11 de_DE
utue.publikation.fachbereich Sonstige - Mathematik und Physik de_DE
utue.publikation.fakultaet 7 Mathematisch-Naturwissenschaftliche Fakultät de_DE
dcterms.DCMIType Text de_DE
utue.publikation.typ doctoralThesis de_DE
utue.opus.id 221 de_DE
thesis.grantor 05/06 Medizinische Fakultät de_DE

Dateien:

This item appears in the following Collection(s)

Show simple item record