Brachytherapy dose-volume histogram computations using optimized stratified sampling methods

Karouzakis, K; Lahanas, M; Milickovic, N; Giannouli, S; Baltas, D; Zamboglou, N

dc.contributor.author	Karouzakis, K	en
dc.contributor.author	Lahanas, M	en
dc.contributor.author	Milickovic, N	en
dc.contributor.author	Giannouli, S	en
dc.contributor.author	Baltas, D	en
dc.contributor.author	Zamboglou, N	en
dc.date.accessioned	2014-03-01T01:17:35Z
dc.date.available	2014-03-01T01:17:35Z
dc.date.issued	2002	en
dc.identifier.issn	0094-2405	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/14578
dc.subject	Algorithms	en
dc.subject	Brachytherapy	en
dc.subject	COIN	en
dc.subject	Dose-volume histograms	en
dc.subject	Stratified sampling	en
dc.subject.classification	Radiology, Nuclear Medicine & Medical Imaging	en
dc.subject.other	accuracy	en
dc.subject.other	algorithm	en
dc.subject.other	anatomy	en
dc.subject.other	article	en
dc.subject.other	brachytherapy	en
dc.subject.other	density	en
dc.subject.other	dose calculation	en
dc.subject.other	histogram	en
dc.subject.other	implant	en
dc.subject.other	priority journal	en
dc.subject.other	radiation dose	en
dc.subject.other	sampling	en
dc.subject.other	Brachytherapy	en
dc.subject.other	Humans	en
dc.subject.other	Models, Statistical	en
dc.subject.other	Radiometry	en
dc.subject.other	Software	en
dc.subject.other	Peru tomato mosaic virus	en
dc.title	Brachytherapy dose-volume histogram computations using optimized stratified sampling methods	en
heal.type	journalArticle	en
heal.identifier.primary	10.1118/1.1450131	en
heal.identifier.secondary	http://dx.doi.org/10.1118/1.1450131	en
heal.language	English	en
heal.publicationDate	2002	en
heal.abstract	A stratified sampling method for the efficient repeated computation of dose-volume histograms (DVHs) in brachytherapy is presented as used for anatomy based brachytherapy optimization methods. The aim of the method is to reduce the number of sampling points required for the calculation of DVHs for the body and the PTV. From the DVHs are derived the quantities such as Conformity Index COIN and COIN integrals. This is achieved by using partial uniform distributed sampling points with a density in each region obtained from a survey of the gradients or the variance of the dose distribution in these regions. The shape of the sampling regions is adapted to the patient anatomy and the shape and size of the implant. For the application of this method a single preprocessing step is necessary which requires only a few seconds. Ten clinical implants were used to study the appropriate number of sampling points, given a required accuracy for quantities such as cumulative DVHs, COIN indices and COIN integrals. We found that DVHs of very large tissue volumes surrounding the PTV, and also COIN distributions, can be obtained using a factor of 5-10 times smaller the number of sampling points in comparison with uniform distributed points. (C) 2002 American Association of Physicists in Medicine.	en
heal.publisher	AMER ASSOC PHYSICISTS MEDICINE AMER INST PHYSICS	en
heal.journalName	Medical Physics	en
dc.identifier.doi	10.1118/1.1450131	en
dc.identifier.isi	ISI:000174408000019	en
dc.identifier.volume	29	en
dc.identifier.issue	3	en
dc.identifier.spage	424	en
dc.identifier.epage	432	en