{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,4]],"date-time":"2026-10-04T00:52:48Z","timestamp":1791075168510,"version":"4.1.0"},"reference-count":15,"publisher":"Springer Science and Business Media LLC","license":[{"start":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T00:00:00Z","timestamp":1790985600000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"},{"start":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T00:00:00Z","timestamp":1790985600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0"}],"content-domain":{"domain":["link.springer.com"],"crossmark-restriction":false},"short-container-title":["Neuroradiology"],"abstract":"<jats:title>Abstract<\/jats:title>\n                  <jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Very small intracranial aneurysms (VSAs\u2009\u2264\u20093\u00a0mm) are increasingly treated endovascularly, yet procedural fragility and long-term durability remain disputed. Device miniaturization and adjunctive balloon- or stent assistance have improved immediate occlusion, but contemporary single-center outcome data with multivariable modeling are sparse.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>We retrospectively analyzed a prospectively maintained database (2013\u20132024) for all VSAs treated endovascularly. Demographics, aneurysm morphology, and procedural details were abstracted from digital subtraction angiography (DSA). At the last follow-up, the primary endpoint was complete occlusion; secondary endpoints were favorable functional outcomes, retreatment, and procedural complications. Multivariable logistic regression was adjusted for rupture status, aneurysm width, location, adjunct use, and immediate occlusion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>One-hundred-eighty-five very small intracranial aneurysms (VSAs\u2009\u2264\u20093\u00a0mm) (median dome 2.6\u00a0mm, 21% &lt; 2\u00a0mm) were treated in 185 patients (median age 57.9 years, 71.9% female). 34% presented ruptured; 56% were bifurcation lesions, most commonly at the anterior communicating complex (34.6%). Balloon-assist, stent-assist, and flow diversion were used in 32.4%, 42.7%, and 4.9%, respectively. Immediate complete occlusion was achieved in 53%; at a median 12-month imaging follow-up, complete occlusion was 74.6%, and the retreatment rate was 9.7%. Procedural complications occurred in 10.8% overall, comprising major complications 2.2% (intra-operative rupture 1.1%, thromboembolism 1.1%) and other complications 8.6% ; there were no procedure-related deaths. 93% of patients had a favorable clinical outcome at 13.6-month clinical follow-up. On multivariable analysis, predictors of complete occlusion at last follow-up were complete occlusion at the end of the procedure (OR 3.53), whereas rupture, posterior-circulation location, width, and diameter\u2009&lt;\u20092\u00a0mm independently reduced obliteration odds.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>Endovascular coiling of VSAs provides high occlusion and excellent clinical outcomes with minimal morbidity. Anatomical complexity (ultra-small size, posterior circulation) and incomplete initial packing remain targets for technical optimization and prospective evaluation.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.1007\/s00234-026-04190-7","type":"journal-article","created":{"date-parts":[[2026,10,3]],"date-time":"2026-10-03T07:31:04Z","timestamp":1791012664000},"update-policy":"https:\/\/doi.org\/10.1007\/springer_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Predictors of complete occlusion in endovascular coiling of very small intracranial aneurysms"],"prefix":"10.1007","author":[{"given":"Ariana","family":"Chacon","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0002-2641-8432","authenticated-orcid":false,"given":"Hasna","family":"Loulida","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5636-0599","authenticated-orcid":false,"given":"Mustafa","family":"Ismail","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1555-0614","authenticated-orcid":false,"given":"Norito","family":"Kenjo","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3138-3484","authenticated-orcid":false,"given":"Julio","family":"Isidor","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Hallmon","family":"Hughes","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alejandro","family":"Spiotta","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"297","published-online":{"date-parts":[[2026,10,3]]},"reference":[{"key":"4190_CR1","doi-asserted-by":"publisher","first-page":"e1087","DOI":"10.1016\/j.wneu.2022.05.108","volume":"164","author":"M Ikegami","year":"2022","unstructured":"Ikegami M et al (2022) Clinical features of ruptured very small intracranial aneurysms (<\u20093\u00a0mm) in patients with subarachnoid hemorrhage. World Neurosurg 164:e1087\u2013e1093","journal-title":"World Neurosurg"},{"key":"4190_CR2","doi-asserted-by":"publisher","first-page":"509","DOI":"10.1007\/s00234-008-0371-0","volume":"50","author":"M Tsutsumi","year":"2008","unstructured":"Tsutsumi M et al (2008) Endovascular treatment of tiny ruptured anterior communicating artery aneurysms. Neuroradiology 50:509\u2013515","journal-title":"Neuroradiology"},{"key":"4190_CR3","doi-asserted-by":"publisher","first-page":"iii66","DOI":"10.1136\/neurintsurg-2012-010537","volume":"5","author":"RM Starke","year":"2013","unstructured":"Starke RM et al (2013) Endovascular treatment of very small ruptured intracranial aneurysms: complications, occlusion rates and prediction of outcome. J neurointerventional Surg 5:iii66\u2013iii71","journal-title":"J neurointerventional Surg"},{"key":"4190_CR4","doi-asserted-by":"publisher","first-page":"862","DOI":"10.3174\/ajnr.A4651","volume":"37","author":"V Yamaki","year":"2016","unstructured":"Yamaki V, Brinjikji W, Murad M, Lanzino G (2016) Endovascular treatment of very small intracranial aneurysms: meta-analysis. Am J Neuroradiol 37:862\u2013867","journal-title":"Am J Neuroradiol"},{"key":"4190_CR5","doi-asserted-by":"publisher","first-page":"123","DOI":"10.1007\/s00701-020-04602-4","volume":"163","author":"JS Catapano","year":"2021","unstructured":"Catapano JS et al (2021) Small intracranial aneurysms in the barrow ruptured aneurysm trial (brat). 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Owing to the retrospective design, the requirement for individual informed consent was waived by the review board.","order":1,"name":"Ethics","label":"Ethics approval and consent to participate","group":{"name":"EthicsHeading","label":"Declaration"}},{"value":"Not applicable.","order":2,"name":"Ethics","label":"Consent for publication","group":{"name":"EthicsHeading","label":"Declaration"}},{"value":"The authors declare no competing interests.","order":3,"name":"Ethics","label":"Competing interest","group":{"name":"EthicsHeading","label":"Declaration"}}]}}