{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,5,14]],"date-time":"2026-05-14T18:09:32Z","timestamp":1778782172060,"version":"3.51.4"},"reference-count":32,"publisher":"IOP Publishing","issue":"7","license":[{"start":{"date-parts":[[2024,3,14]],"date-time":"2024-03-14T00:00:00Z","timestamp":1710374400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/publishingsupport.iopscience.iop.org\/iop-standard\/v1"},{"start":{"date-parts":[[2024,3,14]],"date-time":"2024-03-14T00:00:00Z","timestamp":1710374400000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Phys. Med. Biol."],"published-print":{"date-parts":[[2024,4,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>\n                    <jats:italic>Objective.<\/jats:italic>\n                    The Elekta unity MR-linac delivers step-and-shoot intensity modulated radiotherapy plans using a multileaf collimator (MLC) based on the Agility MLC used on conventional Elekta linacs. Currently, details of the physical Unity MLC and the computational model within its treatment planning system (TPS)\n                    <jats:sc>Monaco<\/jats:sc>\n                    are lacking in published literature. Recently, a novel approach to characterize the physical properties of MLCs was introduced using dynamic synchronous and asynchronous sweeping gap (aSG) tests. Our objective was to develop a step-and-shoot version of the dynamic aSG test to characterize the Unity MLC and the computational MLC models in the\n                    <jats:sc>Monaco<\/jats:sc>\n                    and\n                    <jats:sc>RayStation<\/jats:sc>\n                    TPSs.\n                    <jats:italic>Approach.<\/jats:italic>\n                    Dynamic aSG were discretized into a step-and-shoot aSG by investigating the number of segments\/sweep and the minimal number of monitor units (MU) per segment. The step-and-shoot aSG tests were compared to the dynamic aSG tests on a conventional linac at a source-to-detector distance of 143.5 cm, mimicking the Unity configuration. the step-and-shoot aSG tests were used to characterize the Unity MLC through measurements and dose calculations in both TPSs.\n                    <jats:italic>Main results.<\/jats:italic>\n                    The step-and-shoot aSGs tests with 100 segments and 5 MU\/segment gave results very similar to the dynamic aSG experiments. The effective tongue-and-groove width of the Unity gradually increased up to 1.4 cm from the leaf tip end. The MLC models in\n                    <jats:sc>RayStation<\/jats:sc>\n                    and\n                    <jats:sc>Monaco<\/jats:sc>\n                    agreed with experimental data within 2.0% and 10%, respectively. The largest discrepancies in\n                    <jats:sc>Monaco<\/jats:sc>\n                    were found for aSG tests with &gt;10 mm leaf interdigitation, which are non-typical for clinical plans.\n                    <jats:italic>Significance.<\/jats:italic>\n                    The step-and-shoot aSG tests accurately characterize the MLC in step-and-shoot delivery mode. The MLC model in\n                    <jats:sc>RayStation<\/jats:sc>\n                    2023B accurately describes the tongue-and-groove and leaf tip effects whereas\n                    <jats:sc>Monaco<\/jats:sc>\n                    overestimates the tongue-and-groove shadowing further away from the leaf tip end.\n                  <\/jats:p>","DOI":"10.1088\/1361-6560\/ad2d7d","type":"journal-article","created":{"date-parts":[[2024,2,27]],"date-time":"2024-02-27T17:42:19Z","timestamp":1709055739000},"page":"075004","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Multileaf collimator characterization and modeling for a 1.5 T MR-linac using static synchronous and asynchronous sweeping gaps"],"prefix":"10.1088","volume":"69","author":[{"given":"Roel G J","family":"Kierkels","sequence":"first","affiliation":[{"name":"Radiotherapiegroep, Arnhem\/Deventer,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3770-8486","authenticated-orcid":true,"given":"Victor","family":"Hernandez","sequence":"additional","affiliation":[{"name":"Hospital Sant Joan de Reus, Department of Medical Physics, Reus,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4888-9323","authenticated-orcid":true,"given":"Jordi","family":"Saez","sequence":"additional","affiliation":[{"name":"Hospital Cl\u00ednic de Barcelona, Department of Radiation Oncology, Barcelona,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Agnes","family":"Angerud","sequence":"additional","affiliation":[{"name":"RaySearch Laboratories AB, Stockholm,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6754-3649","authenticated-orcid":true,"given":"Guido C","family":"Hilgers","sequence":"additional","affiliation":[{"name":"Radiotherapiegroep, Arnhem\/Deventer,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kathrin","family":"Surmann","sequence":"additional","affiliation":[{"name":"Radiotherapiegroep, Arnhem\/Deventer,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Danny","family":"Schuring","sequence":"additional","affiliation":[{"name":"Radiotherapiegroep, Arnhem\/Deventer,"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Andr\u00e9 W H","family":"Minken","sequence":"additional","affiliation":[{"name":"Radiotherapiegroep, Arnhem\/Deventer,"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"266","published-online":{"date-parts":[[2024,3,14]]},"reference":[{"key":"pmbad2d7dbib1","author":"F\u00e4lth","year":"2021","type":"other"},{"key":"pmbad2d7dbib2","doi-asserted-by":"publisher","first-page":"14","DOI":"10.1002\/acm2.13641","type":"journal-article","article-title":"AAPM medical physics practice guideline 5.b: commissioning and QA of treatment planning dose calculations\u2014megavoltage photon and electron beams","volume":"16","author":"Geurts","year":"2022","journal-title":"J. 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All rights, including for text and data mining, AI training, and similar technologies, are reserved.","name":"copyright_information","label":"Copyright Information"},{"value":"2023-11-20","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2024-02-27","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2024-03-14","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}