{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,11]],"date-time":"2026-06-11T22:58:36Z","timestamp":1781218716792,"version":"3.54.1"},"reference-count":39,"publisher":"Georg Thieme Verlag KG","issue":"04","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J Neurol Surg A Cent Eur Neurosurg"],"published-print":{"date-parts":[[2026,7]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:p>Anterior communicating artery (ACoA) aneurysms are common and complex. This study investigated the effect of A1 artery variations (hypoplasia\/aplasia) on treatment outcomes.<\/jats:p>\n                  <jats:p>We retrospectively reviewed 104 patients with ACoA aneurysms treated either microsurgically or endovascularly.<\/jats:p>\n                  <jats:p>Ruptured aneurysms were present in 58.7% of patients. A1 variations occurred in 45.2% of cases, more frequently in unruptured aneurysms (69.8%, p\u2009&lt;\u20090.01). The neck width of ruptured aneurysms was significantly smaller than that of unruptured ones. Variations reduced the risk of rupture (odds ratio\u2009=\u20090.16, 95% confidence interval\u2009=\u20090.06\u20130.41; p\u2009=\u20090.001). Microsurgery was the primary treatment (74%), and the rate of A1 variations was significantly lower in these cases (p\u2009&lt;\u20090.05). Second interventions were required in 11.5% of patients, with no significant association to variation or treatment type. Vasospasm occurred in 41% of the ruptured aneurysm cases. Functional outcomes (modified Rankin Scale) were better in patients with A1 variations (p\u2009&lt;\u20090.05). Mortality was 11.5% and unrelated to A1 variation. A higher bottleneck ratio increased mortality risk, whereas a higher height\/width ratio decreased it.<\/jats:p>\n                  <jats:p>A1 variations were more common in unruptured ACoA aneurysms. They did not significantly influence retreatment or mortality. These findings may guide management strategies as the detection of unruptured aneurysms increases.<\/jats:p>","DOI":"10.1055\/a-2790-5115","type":"journal-article","created":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T00:06:51Z","timestamp":1768608411000},"page":"259-267","source":"Crossref","is-referenced-by-count":0,"title":["The Role of A1 Variations on the Outcomes of Anterior Communicating Artery Aneurysm Treatment"],"prefix":"10.1055","volume":"87","author":[{"given":"Feryal","family":"Bastaci","sequence":"additional","affiliation":[{"name":"Mehmet Akif \u0130nan Training and Research Hospital, Neurosurgery Clinic, \u015eanl\u0131urfa, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Erhan","family":"\u00c7eliko\u011flu","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Health Sciences, Hamidiye Faculty of Medicine, \u0130stanbul, Turkey"},{"name":"Fatih Sultan Mehmet Training and Research Hospital, Neurosurgery Clinic, \u0130stanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1444-7076","authenticated-orcid":false,"given":"Tayfun","family":"Hakan","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, University of Health Sciences, Hamidiye Faculty of Medicine, \u0130stanbul, Turkey"},{"name":"Fatih Sultan Mehmet Training and Research Hospital, Neurosurgery Clinic, \u0130stanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"J\u00fclide","family":"Hazneci","sequence":"additional","affiliation":[{"name":"Fatih Sultan Mehmet Training and Research Hospital, Neurosurgery Clinic, \u0130stanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Volga Ula\u015f","family":"Ercan","sequence":"additional","affiliation":[{"name":"Fatih Sultan Mehmet Training and Research Hospital, Radiology Clinic, \u0130stanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Y\u0131lmaz","family":"\u00d6nal","sequence":"additional","affiliation":[{"name":"Fatih Sultan Mehmet Training and Research Hospital, Radiology Clinic, \u0130stanbul, Turkey"},{"name":"Department of Radiology, University of Health Sciences, Hamidiye Faculty of Medicine \u0130stanbul, Turkey"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"194","published-online":{"date-parts":[[2026,4,7]]},"reference":[{"issue":"01","key":"ref1","doi-asserted-by":"crossref","first-page":"18","DOI":"10.3171\/jns.1990.73.1.0018","article-title":"The international cooperative study on the timing of aneurysm surgery: part 1: overall management results","volume":"73","author":"N F Kassell","year":"1990","journal-title":"J Neurosurg"},{"issue":"9342","key":"ref2","doi-asserted-by":"crossref","first-page":"1267","DOI":"10.1016\/S0140-6736(02)11314-6","article-title":"International Subarachnoid Aneurysm Trial (ISAT) of 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