Show simple item record

dc.contributor.authorPartridge, M
dc.contributor.authorEvans, P M
dc.contributor.authorVan Herk, M
dc.contributor.authorPloeger, L S
dc.contributor.authorBudgell, Geoff J
dc.contributor.authorJames, H V
dc.date.accessioned2009-11-23T09:54:58Z
dc.date.available2009-11-23T09:54:58Z
dc.date.issued2000-07
dc.identifier.citationLeaf position verification during dynamic beam delivery: a comparison of three applications using electronic portal imaging. 2000, 27 (7):1601-9 Med Physen
dc.identifier.issn0094-2405
dc.identifier.pmid10947263
dc.identifier.urihttp://hdl.handle.net/10541/86657
dc.description.abstractThe use of a dynamic multileaf collimator (MLC) to deliver intensity-modulated beams presents a problem for conventional verification techniques. The use of electronic portal imaging to track MLC leaves during beam delivery has been shown to provide a solution to this problem. An experimental comparison of three different verification systems, each using a different electronic portal imaging technology, is presented. Two of the systems presented are commercially available imagers with in-house modifications, with the third system being an in-house built experimental system. The random and systematic errors present in each of the verifications systems are measured and presented, together with the study of the effects of varying dose rate and leaf speed on verification system performance. The performance of the three systems is demonstrated to be very similar, with an overall accuracy in comparing measured and prescribed collimator trajectories of approximately +/-1.0 mm. Systematic errors in the percentage delivered dose signal provided by the accelerator are significant and must be corrected for good performance of the current systems. It is demonstrated that, with suitable modifications, commercially available portal imaging systems can be used to verify dynamic MLC beam delivery.
dc.language.isoenen
dc.subject.meshAlgorithms
dc.subject.meshDose-Response Relationship, Radiation
dc.subject.meshImage Processing, Computer-Assisted
dc.subject.meshModels, Statistical
dc.subject.meshRadiotherapy, Computer-Assisted
dc.subject.meshReproducibility of Results
dc.titleLeaf position verification during dynamic beam delivery: a comparison of three applications using electronic portal imaging.en
dc.typeArticleen
dc.contributor.departmentJoint Department of Physics, Institute of Cancer Research and Royal Marsden NHS Trust, Sutton, United Kingdom.en
dc.identifier.journalMedical Physicsen
html.description.abstractThe use of a dynamic multileaf collimator (MLC) to deliver intensity-modulated beams presents a problem for conventional verification techniques. The use of electronic portal imaging to track MLC leaves during beam delivery has been shown to provide a solution to this problem. An experimental comparison of three different verification systems, each using a different electronic portal imaging technology, is presented. Two of the systems presented are commercially available imagers with in-house modifications, with the third system being an in-house built experimental system. The random and systematic errors present in each of the verifications systems are measured and presented, together with the study of the effects of varying dose rate and leaf speed on verification system performance. The performance of the three systems is demonstrated to be very similar, with an overall accuracy in comparing measured and prescribed collimator trajectories of approximately +/-1.0 mm. Systematic errors in the percentage delivered dose signal provided by the accelerator are significant and must be corrected for good performance of the current systems. It is demonstrated that, with suitable modifications, commercially available portal imaging systems can be used to verify dynamic MLC beam delivery.


This item appears in the following Collection(s)

Show simple item record