Registration of electronic portal images for patient set-up verification

Matsopoulos, GK; Asvestas, PA; Delibasis, KK; Kouloulias, V; Uzunoglu, N; Karaiskos, P; Sandilos, P

dc.contributor.author	Matsopoulos, GK	en
dc.contributor.author	Asvestas, PA	en
dc.contributor.author	Delibasis, KK	en
dc.contributor.author	Kouloulias, V	en
dc.contributor.author	Uzunoglu, N	en
dc.contributor.author	Karaiskos, P	en
dc.contributor.author	Sandilos, P	en
dc.date.accessioned	2014-03-01T01:21:17Z
dc.date.available	2014-03-01T01:21:17Z
dc.date.issued	2004	en
dc.identifier.issn	0031-9155	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/16188
dc.subject	Image Registration	en
dc.subject	Radiation Therapy	en
dc.subject	Statistical Significance	en
dc.subject	Digitally Reconstructed Radiograph	en
dc.subject	Electronic Portal Imaging Device	en
dc.subject.classification	Engineering, Biomedical	en
dc.subject.classification	Radiology, Nuclear Medicine & Medical Imaging	en
dc.subject.other	Digitally reconstructed radiographs (DRR)	en
dc.subject.other	Image registration	en
dc.subject.other	Dosimetry	en
dc.subject.other	Image analysis	en
dc.subject.other	Patient treatment	en
dc.subject.other	Radiography	en
dc.subject.other	Medical imaging	en
dc.subject.other	accuracy	en
dc.subject.other	analysis of variance	en
dc.subject.other	analytic method	en
dc.subject.other	analytical error	en
dc.subject.other	article	en
dc.subject.other	automation	en
dc.subject.other	clinical study	en
dc.subject.other	computer assisted radiotherapy	en
dc.subject.other	controlled study	en
dc.subject.other	data analysis	en
dc.subject.other	image analysis	en
dc.subject.other	image processing	en
dc.subject.other	imaging system	en
dc.subject.other	information processing	en
dc.subject.other	methodology	en
dc.subject.other	observer variation	en
dc.subject.other	optical rotation	en
dc.subject.other	patient positioning	en
dc.subject.other	phantom	en
dc.subject.other	priority journal	en
dc.subject.other	registration	en
dc.subject.other	reproducibility	en
dc.subject.other	statistical significance	en
dc.subject.other	Algorithms	en
dc.subject.other	Computer Simulation	en
dc.subject.other	Electrons	en
dc.subject.other	Humans	en
dc.subject.other	Image Processing, Computer-Assisted	en
dc.subject.other	Models, Anatomic	en
dc.subject.other	Models, Statistical	en
dc.subject.other	Models, Theoretical	en
dc.subject.other	Phantoms, Imaging	en
dc.subject.other	Radiographic Image Enhancement	en
dc.subject.other	Radiotherapy Planning, Computer-Assisted	en
dc.subject.other	Radiotherapy, Computer-Assisted	en
dc.subject.other	Radiotherapy, Conformal	en
dc.subject.other	Reproducibility of Results	en
dc.subject.other	Software	en
dc.subject.other	Statistics	en
dc.title	Registration of electronic portal images for patient set-up verification	en
heal.type	journalArticle	en
heal.identifier.primary	10.1088/0031-9155/49/14/018	en
heal.identifier.secondary	http://dx.doi.org/10.1088/0031-9155/49/14/018	en
heal.language	English	en
heal.publicationDate	2004	en
heal.abstract	Images acquired from an electronic portal imaging device are aligned with digitally reconstructed radiographs (DRRs) or other portal images to verify patient positioning during radiation therapy. Most of the currently available computer aided registration methods are based on the manual placement of corresponding landmarks. The purpose of the paper is twofold: (a) the establishment of a methodology for patient set-up verification during radiotherapy based on the registration of electronic portal images, and (b) the evaluation of the proposed methodology in a clinical environment. The estimation of set-up errors, using the proposed methodology, can be accomplished by matching the portal image of the current fraction of the treatment with the portal image of the baseline treatment (reference portal image) using a nearly automated technique. The proposed registration method is tested on a number of phantom data as well as on data from four patients. The phantom data included portal images that corresponded to various positions of the phantom on the treatment couch. For each patient, a set of 30 portal images was used. For the phantom data (for both transverse and lateral portal images), the maximum absolute deviations of the translational shifts were within 1.5 mm, whereas the in-plane rotation angle error was less than 0.5°. The two-way Anova revealed no statistical significant variability both within observer and between-observer measurements (P > 0.05). For the patient data, the mean values obtained with manual and the proposed registration methods were within 0.5 mm. In conclusion, the proposed registration method has been incorporated within a system, called ESTERR-PRO. Its image registration capability achieves high accuracy and both intra- and inter-user reproducibility. The system is fully operational within the Radiotherapy Department of 'HYGEIA' Hospital in Athens and it could be easily installed in any other clinical environment since it requires standardized hardware specifications and minimal human intervention. © 2004 IOP Publishing Ltd.	en
heal.publisher	IOP PUBLISHING LTD	en
heal.journalName	Physics in Medicine and Biology	en
dc.identifier.doi	10.1088/0031-9155/49/14/018	en
dc.identifier.isi	ISI:000223285900018	en
dc.identifier.volume	49	en
dc.identifier.issue	14	en
dc.identifier.spage	3279	en
dc.identifier.epage	3289	en