{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,30]],"date-time":"2026-06-30T07:05:42Z","timestamp":1782803142637,"version":"3.54.5"},"reference-count":32,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T00:00:00Z","timestamp":1775606400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Neurol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Flow diversion stents (FDS), particularly the Pipeline Embolization Device (PED), have been widely used for intracranial aneurysm (IA) treatment. However, data on PED deployment in small-caliber parent vessels (&amp;lt; 2\u202fmm) remain limited. This study aimed to evaluate the technical feasibility, safety, and efficacy of PED for IAs arising from small-caliber vessels.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>This was a multicenter retrospective study enrolling 71 eligible patients with IA located in parent vessels &amp;lt; 2\u202fmm who underwent PED implantation. The primary safety endpoint included procedure-related death, symptomatic stroke, intracranial hemorrhage and asymptomatic in-stent stenosis; the primary efficacy endpoint was complete aneurysm occlusion [O\u2019Kelly-Marotta (OKM) grade D] on follow-up digital subtraction angiography (DSA). Binary logistic regression analyses were used to identify factors associated with complications and delayed IA occlusion.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      The patient age was 55 (47, 59) years, with 37 (52.1%) males. The follow-up duration was 9 (7, 15) months. Postoperative complications included ischemic events (16.9%), hemorrhagic events (4.2%), and asymptomatic in-stent stenosis (12.7%). The 1-year complete occlusion rate was 52%, whereas the long-term occlusion rate gradually increased to 80% with follow-up beyond 12\u202fmonths. Univariable analysis showed PED length was associated with both delayed IA occlusion [odds ratio (OR)\u202f=\u202f0.91, 95% confidence interval (CI)\u202f=\u202f0.83\u20131.00;\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.040] and ischemic complications (OR\u202f=\u202f1.36, 95% CI\u202f=\u202f1.11\u20131.66;\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.003) and also revealed that pre-existing parent vessel stenosis was strongly associated with asymptomatic in-stent stenosis (OR\u202f=\u202f13.50, 95% CI\u202f=\u202f2.80\u201365.04;\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.001); multivariable analysis confirmed PED length as an independent predictor of ischemic complications (OR\u202f=\u202f1.31, 95% CI\u202f=\u202f1.06\u20131.63;\n                      <jats:italic>p<\/jats:italic>\n                      \u202f=\u202f0.013).\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>PED deployment in small-caliber parent vessels (&amp;lt;2\u202fmm) is technically feasible and clinically viable, with favorable IA occlusion rates and an acceptable safety profile. These findings support the off-label use of PEDs in this challenging cohort, provided rigorous patient selection, optimal procedural planning and close follow-up are implemented.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fneur.2026.1778770","type":"journal-article","created":{"date-parts":[[2026,4,8]],"date-time":"2026-04-08T04:12:34Z","timestamp":1775621554000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Multicenter experience of pipeline embolization device used in small caliber vessels (&lt; 2\u202fmm) for intracranial aneurysm treatment and mid-term results"],"prefix":"10.3389","volume":"17","author":[{"given":"Huijian","family":"Ge","sequence":"first","affiliation":[{"name":"Department of Neurosurgery, Beijing Tiantan Hospital and Beijing Neurosurgical Institute, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Siming","family":"Gui","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Beijing Tiantan Hospital and Beijing Neurosurgical Institute, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jia","family":"Jiang","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Beijing Tiantan Hospital and Beijing Neurosurgical Institute, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Zhao","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiheng","family":"Chen","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Beijing Chaoyang Hospital, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sheng","family":"Bi","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Beijing Tiantan Hospital and Beijing Neurosurgical Institute, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lu","family":"Zheng","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Beijing Tiantan Hospital and Beijing Neurosurgical Institute, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jiahe","family":"Wei","sequence":"additional","affiliation":[{"name":"School of Basic Medical Sciences, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Youxiang","family":"Li","sequence":"additional","affiliation":[{"name":"Department of Neurosurgery, Beijing Tiantan Hospital and Beijing Neurosurgical Institute, Capital Medical University","place":["Beijing, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,4,8]]},"reference":[{"key":"ref1","doi-asserted-by":"publisher","first-page":"2103","DOI":"10.1161\/STROKEAHA.120.029296","article-title":"Determinants of the presence and size of intracranial aneurysms in the general population: the Rotterdam study","volume":"51","author":"Cras","year":"2020","journal-title":"Stroke"},{"key":"ref2","doi-asserted-by":"publisher","first-page":"251","DOI":"10.1161\/01.str.29.1.251","article-title":"Prevalence and risk of rupture of intracranial aneurysms: a systematic 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