{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,4]],"date-time":"2026-09-04T00:16:23Z","timestamp":1788480983579,"version":"build-2803163510"},"reference-count":31,"publisher":"Wiley","issue":"11","license":[{"start":{"date-parts":[[2025,10,27]],"date-time":"2025-10-27T00:00:00Z","timestamp":1761523200000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/onlinelibrary.wiley.com\/termsAndConditions#vor"},{"start":{"date-parts":[[2025,10,27]],"date-time":"2025-10-27T00:00:00Z","timestamp":1761523200000},"content-version":"tdm","delay-in-days":0,"URL":"http:\/\/doi.wiley.com\/10.1002\/tdm_license_1.1"}],"funder":[{"DOI":"10.13039\/501100001102","name":"Cancer Council NSW","doi-asserted-by":"publisher","id":[{"id":"10.13039\/501100001102","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["aapm.onlinelibrary.wiley.com"],"crossmark-restriction":true},"short-container-title":["Medical Physics"],"published-print":{"date-parts":[[2025,11]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Real\u2010time image\u2010guided radiotherapy (IGRT) is critical for accurate dose delivery during stereotactic body radiotherapy (SBRT). Beam's eye view (BEV) imaging offers the unique advantage of reporting motion in the most dosimetrically relevant frame of reference without additional imaging dose. However, its clinical use is limited by poor contrast\u2010to\u2010noise ratio and marker occlusion by treatment beam apertures. Deep learning enables fast identification of indistinct marker features even in low contrast images, facilitating real\u2010time BEV\u2010IGRT. To support integration with standard\u2010equipped linear accelerators, accurate 3D localization is essential\u2014necessitating the development of a 3D BEV\u2010IGRT system.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Purpose<\/jats:title>\n                    <jats:p>This study aimed to develop and experimentally evaluate a novel real\u2010time 3D BEV\u2010IGRT system for potential clinical implementation during prostate SBRT.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>A real\u2010time 3D BEV\u2010IGRT system was developed by integrating a deep learning\u2010based 2D MV marker segmentation method with a 3D IGRT framework. Marker positions were segmented on MV images using a convolutional neural network (CNN) and used to predict 3D motion via a Gaussian maximum likelihood estimation method. A failure mode and effects analysis (FMEA) was performed by a multidisciplinary team. Mitigation strategies were implemented for high\u2010risk failure modes, and risk priority numbers (RPN) were recalculated.<\/jats:p>\n                    <jats:p>\n                      Experimental system evaluation was guided by failure modes identified through the FMEA. An anthropomorphic pelvic phantom with three implanted gold markers was mounted on a 3D motion\u2010programmable platform. System performance was assessed under static and dynamic conditions, using treatment plans of increasing complexity, ranging from open fields to patient\u2010representative volumetric modulated arc therapy plans. Dynamic performance was evaluated using four patient\u2010derived prostate motion traces. Localization accuracy (mean error\u00a0\u00b1\u00a01 SD) was assessed by comparing system\u2010reported positions to ground truth derived from known motion trajectories or static displacements. 5\n                      <jats:sup>th<\/jats:sup>\n                      \/95\n                      <jats:sup>th<\/jats:sup>\n                      error percentiles were calculated. System latency was measured as the time delay between motion initiation and system\u2010reported displacement. Clinically acceptable accuracy was defined as within\u00a0\u00b1\u00a02\u00a0mm in the superior\u2010inferior (SI), anterior\u2010posterior (AP) and left\u2010right (LR) directions, and latency \u2264 500\u00a0ms.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Forty\u2010six failure modes were identified through the FMEA. High\u2010risk failure causes included algorithmic limitations, algorithmic errors, human error, and marker occlusion. Incorporation of mitigation strategies\u2014including eligibility screening, staff training, and workflow formalization\u2014resulted in an average RPN reduction of 43% across the top ten high\u2010risk failure modes. A risk\u2010informed quality assurance program was designed to support clinical implementation.<\/jats:p>\n                    <jats:p>\n                      Overall 3D BEV\u2010IGRT system accuracy was 0.1\u00a0\u00b1\u00a00.7\u00a0mm (SI), \u20100.1\u00a0\u00b1\u00a00.8\u00a0mm (AP), and 0.1\u00a0\u00b1\u00a00.7\u00a0mm (LR). Accuracy remained within\u00a0\u00b1\u00a02\u00a0mm in all directions across all individual tests. Overall 5\n                      <jats:sup>th<\/jats:sup>\n                      \/95\n                      <jats:sup>th<\/jats:sup>\n                      percentile errors were [\u20101.0, 1.3] mm (SI), [\u20101.2, 0.9] mm (AP), and [\u20100.9, 1.0] mm (LR). System latency was 300\u00a0\u00b1\u00a0100\u00a0ms.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>The 3D BEV\u2010IGRT system was experimentally validated, demonstrating clinically acceptable localization accuracy and latency, supporting its feasibility for clinical implementation. Integrated risk mitigation strategies effectively reduced workflow risk and promoted understanding of system vulnerabilities. Deployment is planned for a prostate SBRT clinical trial.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1002\/mp.70086","type":"journal-article","created":{"date-parts":[[2025,10,28]],"date-time":"2025-10-28T04:20:16Z","timestamp":1761625216000},"update-policy":"https:\/\/doi.org\/10.1002\/crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Experimental investigation of real\u2010time 3D beam's eye view image\u2010guided radiotherapy for prostate SBRT"],"prefix":"10.1002","volume":"52","author":[{"given":"Danielle","family":"Chrystall","sequence":"first","affiliation":[{"name":"Northern Sydney Cancer Center Royal North Shore Hospital  St Leonards New South Wales Australia"},{"name":"Institute of Medical Physics University of Sydney  Camperdown New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maegan","family":"Stewart","sequence":"additional","affiliation":[{"name":"Northern Sydney Cancer Center Royal North Shore Hospital  St Leonards New South Wales Australia"},{"name":"Faculty of Medicine and Health University of Sydney  Camperdown New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Freeman","family":"Jin","sequence":"additional","affiliation":[{"name":"Image X Institute University of Sydney  Eveleigh New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chandrima","family":"Sengupta","sequence":"additional","affiliation":[{"name":"Image X Institute University of Sydney  Eveleigh New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"D'Oliveira","sequence":"additional","affiliation":[{"name":"Institute of Medical Physics University of Sydney  Camperdown New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alannah","family":"Kejda","sequence":"additional","affiliation":[{"name":"Northern Sydney Cancer Center Royal North Shore Hospital  St Leonards New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Levi","family":"Madden","sequence":"additional","affiliation":[{"name":"Northern Sydney Cancer Center Royal North Shore Hospital  St Leonards New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Doan Trang","family":"Nguyen","sequence":"additional","affiliation":[{"name":"SeeTreat Medical  Sydney New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Paul","family":"Keall","sequence":"additional","affiliation":[{"name":"Image X Institute University of Sydney  Eveleigh New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jeremy","family":"Booth","sequence":"additional","affiliation":[{"name":"Northern Sydney Cancer Center Royal North Shore Hospital  St Leonards New South Wales Australia"},{"name":"Institute of Medical Physics University of Sydney  Camperdown New South Wales Australia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"311","published-online":{"date-parts":[[2025,10,27]]},"reference":[{"key":"e_1_2_9_2_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijrobp.2019.03.051"},{"key":"e_1_2_9_3_1","doi-asserted-by":"publisher","DOI":"10.1001\/jamaoncol.2022.6558"},{"key":"e_1_2_9_4_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijrobp.2024.07.2325"},{"key":"e_1_2_9_5_1","doi-asserted-by":"publisher","DOI":"10.1186\/s12885\u2010017\u20103164\u20101"},{"key":"e_1_2_9_6_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijrobp.2012.07.2367"},{"key":"e_1_2_9_7_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijrobp.2015.10.009"},{"key":"e_1_2_9_8_1","doi-asserted-by":"publisher","DOI":"10.1002\/acm2.12614"},{"key":"e_1_2_9_9_1","doi-asserted-by":"publisher","DOI":"10.1002\/acm2.13593"},{"key":"e_1_2_9_10_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.13259"},{"key":"e_1_2_9_11_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.4944737"},{"key":"e_1_2_9_12_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijrobp.2007.11.054"},{"key":"e_1_2_9_13_1","doi-asserted-by":"publisher","DOI":"10.1002\/acm2.12390"},{"key":"e_1_2_9_14_1","doi-asserted-by":"publisher","DOI":"10.1088\/2057\u20101976\/abce0c"},{"key":"e_1_2_9_15_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.3218845"},{"key":"e_1_2_9_16_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361\u20106560\/ac1246"},{"key":"e_1_2_9_17_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.4927786"},{"key":"e_1_2_9_18_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361\u20106560\/acc77c"},{"key":"e_1_2_9_19_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.13784"},{"key":"e_1_2_9_20_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.13519"},{"key":"e_1_2_9_21_1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijrobp.2008.07.037"},{"key":"e_1_2_9_22_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.4790564"},{"key":"e_1_2_9_23_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.4947547"},{"key":"e_1_2_9_24_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.4898119"},{"key":"e_1_2_9_25_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361\u20106560\/ab5d8b"},{"key":"e_1_2_9_26_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.3158812"},{"key":"e_1_2_9_27_1","unstructured":"Optimal Prostate Study.https:\/\/clinicaltrials.gov\/study\/NCT03386045"},{"key":"e_1_2_9_28_1","unstructured":"Accuracy (trueness and precision) of measurements methods and results. ISO Standard No 5725\u20104:2020: International Organization of Standardization;2020."},{"key":"e_1_2_9_29_1","doi-asserted-by":"publisher","DOI":"10.1002\/mp.14625"},{"key":"e_1_2_9_30_1","doi-asserted-by":"publisher","DOI":"10.1088\/1361\u20106560\/aaae8b"},{"key":"e_1_2_9_31_1","doi-asserted-by":"publisher","DOI":"10.1118\/1.4862509"},{"key":"e_1_2_9_32_1","unstructured":"Continuous Monitoring of Prostate Position During Radiotherapy (KIM Gating). Recruiting Royal North Shore Hospital.https:\/\/clinicaltrials.gov\/study\/NCT01742403"}],"updated-by":[{"DOI":"10.1002\/mp.70417","type":"correction","label":"Correction","source":"publisher","updated":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T00:00:00Z","timestamp":1778544000000}}],"container-title":["Medical Physics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/aapm.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/mp.70086","content-type":"application\/pdf","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/aapm.onlinelibrary.wiley.com\/doi\/full-xml\/10.1002\/mp.70086","content-type":"application\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/aapm.onlinelibrary.wiley.com\/doi\/pdf\/10.1002\/mp.70086","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,4,12]],"date-time":"2026-04-12T07:46:47Z","timestamp":1775980007000},"score":1,"resource":{"primary":{"URL":"https:\/\/aapm.onlinelibrary.wiley.com\/doi\/10.1002\/mp.70086"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,10,27]]},"references-count":31,"journal-issue":{"issue":"11","published-print":{"date-parts":[[2025,11]]}},"alternative-id":["10.1002\/mp.70086"],"URL":"https:\/\/doi.org\/10.1002\/mp.70086","archive":["Portico"],"relation":{},"ISSN":["0094-2405","2473-4209"],"issn-type":[{"value":"0094-2405","type":"print"},{"value":"2473-4209","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,10,27]]},"assertion":[{"value":"2025-08-19","order":0,"name":"received","label":"Received","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-09-26","order":2,"name":"accepted","label":"Accepted","group":{"name":"publication_history","label":"Publication History"}},{"value":"2025-10-27","order":3,"name":"published","label":"Published","group":{"name":"publication_history","label":"Publication History"}}],"article-number":"e70086"}}