title: Endovascular Treatment of Very Small Intracranial Aneurysms: Meta-Analysis.
abstract: Outcomes of endovascular treatment of very small intracranial aneurysms are still not well-characterized. Recently, several series assessing coil embolization of tiny aneurysms have presented new promising results. Thus, we performed a systematic review and meta-analysis of studies evaluating endovascular treatment of very small intracranial aneurysms.
  
  
  
  We conducted a computerized search of Scopus, Medline, and the Web of Science for studies on endovascular treatment of very small (≤3 mm in diameter) intracranial aneurysms published between January 1996 and May 2015. Using a random-effects model, we evaluated clinical and angiographic outcomes.
  
  
  
  Twenty-two studies with 1105 tiny aneurysms (844 ruptured and 261 unruptured) endovascularly treated were included. Postoperative and long-term complete occlusion was achieved in 85% (95% CI, 78%-90%) and 91% (95% CI, 87%-94%) of aneurysms, respectively. The recanalization rate was 6% (95% CI, 4%-11%) and retreatment occurred in 7% (95% CI, 5%-9%) of cases. Seventy-nine percent (95% CI, 64%-89%) of patients had good neurologic outcome at long-term follow-up. Intraprocedural rupture occurred in 7% (95% CI, 5%-9%) of the coiling procedures, while thromboembolic complications occurred in 4% (95% CI, 3%-6%).
  
  
  
  Coil embolization of very small intracranial aneurysms can be performed safely and effectively. In the case of unruptured aneurysms, procedure-related complications are not negligible. Patients and providers should consider such risks when engaged in a shared decision-making process.
authors.affiliation: From the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Foundation (V.N.Y.), Ministry of Education of Brazil, Brasilia, Brazil.
authors.forename: V N
authors.identifier: 0000-0003-4872-1731
authors.initials: VN
authors.lastname: Yamaki
authors.affiliation: Department of Radiology (W.B.) brinjikji.waleed@mayo.edu.
authors.forename: W
authors.identifier: 0000-0001-5271-5524
authors.initials: W
authors.lastname: Brinjikji
authors.affiliation: Center for Science of Healthcare Delivery (M.H.M.).
authors.forename: M H
authors.identifier: 0000-0001-5502-5975
authors.initials: MH
authors.lastname: Murad
authors.affiliation: Department of Neurosurgery (G.L.), Mayo Clinic, Rochester, Minnesota.
authors.forename: G
authors.identifier: 0000-0003-1479-465X
authors.initials: G
authors.lastname: Lanzino
mesh_terms: D004621:Embolization, Therapeutic / Q000379:methods*; D057510:Endovascular Procedures / Q000379:methods*; D006801:Humans; D002532:Intracranial Aneurysm / Q000473:pathology / Q000628:therapy*; D019635:Neurosurgical Procedures / Q000379:methods*; D016896:Treatment Outcome