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The present study investigated quantitative angiographic markers contributing to symptomatic RICs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Materials and methods<\/jats:title>\n                    <jats:p>A total of 131 patients with supratentorial BAVMs who had not received prior treatment and underwent radiosurgery between 2011 and 2020 were included. Patients completed \u2265 24 months of MRI and clinical follow-up. MRIs and angiograms taken before radiosurgery were analyzed for morphological characteristics and quantitative angiographic parameters. Symptomatic RICs were defined as neurological symptoms attributed to RICs. The vein-artery (VA) ratio was defined as the sum of all draining vein diameters divided by the sum of all supplying artery diameters. The modified cerebral circulation time (mCCT) was defined as the interval between the bolus arrival time of the ipsilateral cavernous internal carotid artery and the parietal vein. Logistic regression models were used to evaluate associations between these markers and symptomatic RICs.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Symptomatic RICs developed in 27 (20.6%) of 131 patients. Nine patients with symptomatic RICs were hospitalized. Multivariable analysis revealed that a lower VA ratio and shorter mCCT were independently associated with symptomatic RICs. Furthermore, the quantitative angiographic model exhibited a higher performance in association with symptomatic RICs than the angioarchitectural model did.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>A lower VA ratio and shorter mCCT were quantitative angiographic markers of venous outflow impairment and high blood flow of BAVMs, respectively. These markers may quantify the hemodynamic effect that contributes to symptomatic RICs development in patients with BAVMs after radiosurgery.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Key Points<\/jats:title>\n                    <jats:p>\n                      <jats:bold>\n                        <jats:italic>Question<\/jats:italic>\n                      <\/jats:bold>\n                      <jats:italic>Can quantitative angiographic markers be used to evaluate the risks of symptomatic radiation-induced changes (RICs) in patients with brain arteriovenous malformations (BAVMs) after radiosurgery?<\/jats:italic>\n                    <\/jats:p>\n                    <jats:p>\n                      <jats:bold>\n                        <jats:italic>Findings<\/jats:italic>\n                      <\/jats:bold>\n                      <jats:italic>BAVMs with a lower vein-artery ratio or shorter modified cerebral circulation time were associated with higher risks of symptomatic RICs development.<\/jats:italic>\n                    <\/jats:p>\n                    <jats:p>\n                      <jats:bold>\n                        <jats:italic>Clinical relevance<\/jats:italic>\n                      <\/jats:bold>\n                      <jats:italic>Quantification of the BAVM hemodynamic effect that contributes to symptomatic RICs development may help therapeutic decision-making for patients with BAVMs after radiosurgery.<\/jats:italic>\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Graphical Abstract<\/jats:title>\n                  <\/jats:sec>","DOI":"10.1007\/s00330-025-11884-8","type":"journal-article","created":{"date-parts":[[2025,7,31]],"date-time":"2025-07-31T19:48:23Z","timestamp":1753991303000},"page":"901-915","update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Quantitative angiographic markers associated with symptomatic radiation-induced changes in supratentorial brain arteriovenous malformations after radiosurgery"],"prefix":"10.1007","volume":"36","author":[{"given":"Wei-Lun","family":"Kao","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chung-Jung","family":"Lin","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jing Kai","family":"Loo","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Huai-Che","family":"Yang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Cheng-Chia","family":"Lee","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sanford PC.","family":"Hsu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Hong-Jen","family":"Chiou","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Feng-Chi","family":"Chang","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kang-Du","family":"Liu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4786-0791","authenticated-orcid":false,"given":"Yong-Sin","family":"Hu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"297","published-online":{"date-parts":[[2025,7,31]]},"reference":[{"key":"11884_CR1","doi-asserted-by":"publisher","first-page":"1900","DOI":"10.1093\/brain\/124.10.1900","volume":"124","author":"R Al-Shahi","year":"2001","unstructured":"Al-Shahi R, Warlow C (2001) A systematic review of the frequency and prognosis of arteriovenous malformations of the brain in adults. 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