A multiobjective gradient-based dose optimization algorithm for external beam conformal radiotherapy

Cotrutz, C; Lahanas, M; Kappas, C; Baltas, D

dc.contributor.author	Cotrutz, C	en
dc.contributor.author	Lahanas, M	en
dc.contributor.author	Kappas, C	en
dc.contributor.author	Baltas, D	en
dc.date.accessioned	2014-03-01T01:16:01Z
dc.date.available	2014-03-01T01:16:01Z
dc.date.issued	2001	en
dc.identifier.issn	00319155	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/13882
dc.subject.other	Algorithms	en
dc.subject.other	Dosimetry	en
dc.subject.other	Gradient methods	en
dc.subject.other	Medical applications	en
dc.subject.other	Optimization	en
dc.subject.other	Conformal radiotherapy	en
dc.subject.other	Radiotherapy	en
dc.subject.other	algorithm	en
dc.subject.other	analysis	en
dc.subject.other	article	en
dc.subject.other	calculation	en
dc.subject.other	controlled study	en
dc.subject.other	decision making	en
dc.subject.other	development	en
dc.subject.other	feasibility study	en
dc.subject.other	intermethod comparison	en
dc.subject.other	priority journal	en
dc.subject.other	radiation dose	en
dc.subject.other	radiotherapy	en
dc.subject.other	weight	en
dc.subject.other	Algorithms	en
dc.subject.other	Dose-Response Relationship, Radiation	en
dc.subject.other	Humans	en
dc.subject.other	Male	en
dc.subject.other	Neoplasms	en
dc.subject.other	Prostate	en
dc.subject.other	Prostatic Neoplasms	en
dc.subject.other	Radioisotopes	en
dc.subject.other	Radiotherapy Planning, Computer-Assisted	en
dc.subject.other	Radiotherapy, Conformal	en
dc.subject.other	Tissue Distribution	en
dc.title	A multiobjective gradient-based dose optimization algorithm for external beam conformal radiotherapy	en
heal.type	journalArticle	en
heal.identifier.primary	10.1088/0031-9155/46/8/309	en
heal.identifier.secondary	http://dx.doi.org/10.1088/0031-9155/46/8/309	en
heal.publicationDate	2001	en
heal.abstract	A multiobjective gradient-based algorithm has been developed for the purpose of dose distribution optimization in external beam conformal radiotherapy. This algorithm is based on the concept of gathering the values of all objectives into a single value. The weighting factors of the composite objective values are varied in different steps, allowing the reconstruction of the trade-off surfaces (three or more objectives) or curves (two objectives) which define the boundary between the feasible and non-feasible domain regions. The analysis of these curves allows the decision-maker to select the solution that best fits the clinical goals. In contrast to all the other algorithms, our method provides not a single solution but a sample of solutions representing all possible clinical importance factors (weights) for the objectives used. The application of this algorithm to two test cases shows that a correct selection for the importance factors to multiply the individual objectives in the global objective value is not trivial and that the location and shape of the boundary region between the feasible and non-feasible solution regions are case dependent. Provided that the individual objective functions are analytically differentiable and that the number of objectives is the range of two to three, the computation times are acceptable for clinical use. Furthermore, the optimization for a unique combination of importance factors within the aggregate objective function is performed in less than 1 min.	en
heal.journalName	Physics in Medicine and Biology	en
dc.identifier.doi	10.1088/0031-9155/46/8/309	en
dc.identifier.volume	46	en
dc.identifier.issue	8	en
dc.identifier.spage	2161	en
dc.identifier.epage	2175	en