{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T07:12:00Z","timestamp":1789456320612,"version":"build-2803163510"},"reference-count":36,"publisher":"IOP Publishing","issue":"17","license":[{"start":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:00:00Z","timestamp":1789430400000},"content-version":"vor","delay-in-days":1,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"},{"start":{"date-parts":[[2026,9,15]],"date-time":"2026-09-15T00:00:00Z","timestamp":1789430400000},"content-version":"tdm","delay-in-days":1,"URL":"https:\/\/iopscience.iop.org\/info\/page\/text-and-data-mining"}],"funder":[{"name":"Scientific Research Project of Hunan Provincial Health Commission","award":["20257423"],"award-info":[{"award-number":["20257423"]}]},{"DOI":"10.13039\/501100004735","name":"Hunan Provincial Natural Science Foundation of China","doi-asserted-by":"crossref","award":["2026JJ60322"],"award-info":[{"award-number":["2026JJ60322"]}],"id":[{"id":"10.13039\/501100004735","id-type":"DOI","asserted-by":"crossref"}]},{"name":"High-Level Talent Support Program of Hunan Cancer Hospital","award":["20250730-1004"],"award-info":[{"award-number":["20250730-1004"]}]}],"content-domain":{"domain":["iopscience.iop.org"],"crossmark-restriction":false},"short-container-title":["Phys. Med. Biol."],"published-print":{"date-parts":[[2026,9,14]]},"abstract":"Abstract<\/jats:title>\n \n Objective.<\/jats:italic>\n This study proposes a 2\n \u03c0<\/jats:italic>\n solid angle-based heuristic framework for non-coplanar volumetric modulated arc therapy (VMAT) in patients with multiple brain metastases (MBM) to automate treatment angle selection.\n Approach.<\/jats:italic>\n Fifty-two patients with MBM (2\u20138 targets) were retrospectively included. A hybrid heuristic framework was constructed: first, a volume-weighted cumulative tumor-skin distance (VW-CTSD) metric was introduced to quantify geometric requirements in the 2\n \u03c0<\/jats:italic>\n solid angle space and to automatically identify non-coplanar trajectories minimizing normal brain exposure. Subsequently, a blocking factor-based sub-arc segmentation and collimator-angle selection strategy determined the sub-arc splitting and collimator angles. Using 30 Gy\/5 fractions, three plans were generated for each patient: manual expert planning (\n P<\/jats:italic>\n ref<\/jats:sub>\n ), VW-CTSD-guided trajectory selection alone (\n P<\/jats:italic>\n tsd<\/jats:sub>\n ), and the proposed combined heuristic strategy (\n P<\/jats:italic>\n com<\/jats:sub>\n ). Dosimetric metrics and plan parameters were compared.\n Main results.<\/jats:italic>\n All plans met clinical goals.\n P<\/jats:italic>\n tsd<\/jats:sub>\n achieved automated trajectory selection with plan quality comparable to\n P<\/jats:italic>\n ref<\/jats:sub>\n . Values are presented as median (P25\u2013P75). Compared with\n P<\/jats:italic>\n ref<\/jats:sub>\n ,\n P<\/jats:italic>\n com<\/jats:sub>\n improved CI [0.86 (0.85\u20130.89) to 0.89 (0.85\u20130.91)] and reduced GI [3.37 (3.17\u20133.79) to 3.09 (2.74\u20133.48)].\n P<\/jats:italic>\n com<\/jats:sub>\n also reduced normal brain tissue (NBT)\n V<\/jats:italic>\n 12Gy<\/jats:sub>\n , MU, and CM from 92.45 (62.54\u2013141.46) to 83.57 (50.30\u2013125.10) cc, from 2391 (2144\u20132527) to 1938 (1845\u20132085), and from 0.22 (0.21\u20130.24) to 0.20 (0.19\u20130.21), respectively. Control-point aperture analysis showed\n X<\/jats:italic>\n -axis narrowing [129.75 (110.60\u2013146.35) to 101.91 (83.34\u2013120.20) mm] and\n Y<\/jats:italic>\n -axis expansion [98.70 (80.13\u2013105.86) to 119.17 (103.38\u2013133.48) mm] in\n P<\/jats:italic>\n com<\/jats:sub>\n . All\n P<\/jats:italic>\n com<\/jats:sub>\n -versus-\n P<\/jats:italic>\n ref<\/jats:sub>\n comparisons for these metrics were statistically significant (\n P<\/jats:italic>\n < 0.001).\n Significance.<\/jats:italic>\n The proposed combined heuristic framework reduced NBT dose, GI, MU, and CM, suggesting its potential as a practical automated approach for non-coplanar VMAT angle selection in patients with MBM.\n <\/jats:p>","DOI":"10.1088\/1361-6560\/ae9b59","type":"journal-article","created":{"date-parts":[[2026,8,18]],"date-time":"2026-08-18T22:53:40Z","timestamp":1787093620000},"page":"175042","update-policy":"https:\/\/doi.org\/10.1088\/crossmark-policy","source":"Crossref","is-referenced-by-count":0,"title":["A 2\n \u03c0<\/i>\n solid angle-based heuristic framework for non-coplanar VMAT in multiple brain metastases"],"prefix":"10.1088","volume":"71","author":[{"ORCID":"https:\/\/orcid.org\/0009-0004-1575-059X","authenticated-orcid":true,"given":"Shixiong","family":"Huang","sequence":"first","affiliation":[{"name":"The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University\/Hunan Cancer Hospital"},{"name":"School of Nuclear Science and Technology, University of South China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Songhua","family":"Yang","sequence":"additional","affiliation":[{"name":"Hunan Cancer Hospital\/the Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Dong","sequence":"additional","affiliation":[{"name":"National Clinical Research Center for Cancer, Tianjin\u2019s Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute & Hospital, Tianjin"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sheng","family":"Huang","sequence":"additional","affiliation":[{"name":"National Clinical Research Center for Cancer, Tianjin\u2019s Clinical Research Center for Cancer, Tianjin Medical University Cancer Institute & Hospital, Tianjin"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3399-6057","authenticated-orcid":true,"given":"Xiaohua","family":"Li","sequence":"additional","affiliation":[{"name":"School of Nuclear Science and Technology, University of South China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Biao","family":"Zeng","sequence":"additional","affiliation":[{"name":"The Affiliated Cancer Hospital of Xiangya School of Medicine, Central South University\/Hunan Cancer Hospital"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"266","published-online":{"date-parts":[[2026,9,15]]},"reference":[{"key":"pmbae9b59bib1","doi-asserted-by":"publisher","DOI":"10.1002\/acm2.14267","type":"journal-article","article-title":"Optimization of collimator angle combined island blocking with parked gap achieves superior normal tissue sparing in SBRT planning of multiple liver lesions","volume":"25","author":"Abuduxiku","year":"2024","journal-title":"J. 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Published on behalf of Institute of Physics and Engineering in Medicine by IOP Publishing Ltd","name":"copyright_information","label":"Copyright Information"},{"value":"2026-02-13","name":"date_received","label":"Date Received","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2026-08-18","name":"date_accepted","label":"Date Accepted","group":{"name":"publication_dates","label":"Publication dates"}},{"value":"2026-09-15","name":"date_epub","label":"Online publication date","group":{"name":"publication_dates","label":"Publication dates"}}]}}