title: Endovascular therapy for asymptomatic unruptured intracranial aneurysms: JR-NET and JR-NET2 findings.
abstract: OBJECTIVE
  National registration studies (the Japanese Registry of Neuroendovascular Therapy [JR-NET] and JR-NET2) have determined the current status and outcomes of neuroendovascular therapy (neuro-EVT). We analyzed short-term outcomes of EVT for asymptomatic unruptured intracranial aneurysms (UIAs).
  
  
  METHODS
  We extracted periprocedural information about EVT for 4767 asymptomatic UIAs from 31,968 registered procedural records of all EVT in the JR-NET and JR-NET2 databases. We assessed the features of the aneurysms and procedures, immediate radiographic findings, procedure-related complications, and clinical outcomes at 30 days after the procedures.
  
  
  RESULTS
  We located 80.0% of UIAs in the anterior circulation, and the most frequent were paraclinoid. The diameter of 2.5%, 32.9%, 51.9%, 12.0%, and 0.7% of the UIAs was <3, 3 to 4, 5 to 9, 10 to 19, and >20 mm, respectively. EVT failed in only 2.1%. Adjunctive techniques were applied in 54.8% of procedures. Pre- and postprocedural antiplatelet agents were prescribed in 85.6% and 84.0%, respectively, of the procedures. The immediate radiographic outcomes of 57.7%, 31.9%, and 10.0% of the UIAs comprised complete occlusion, residual necks, and residual aneurysms, respectively. Complications that were associated with 9.1% of procedures comprised 2.0% hemorrhagic and 4.6% ischemic, and the 30-day morbidity and mortality rates were 2.12% and 0.31%, respectively.
  
  
  CONCLUSIONS
  The radiographic results of EVT for asymptomatic UIAs in Japan were acceptable, with low mortality and morbidity rates.
authors.affiliation: From the Department of Neurosurgery, Graduate School of Medicine, Osaka University, Suita, Japan (T.S., T.F., T.Y.); Department of Neurosurgery, Kobe City Medical Center General Hospital, Kobe, Japan (H.I., N.S.); Department of Neurosurgery, Graduate School of Medicine, Kyoto University, Kyoto, Japan (A.I.); and Division of Neuroendovascular Treatment, Institute of Biomedical Research and Innovation, Kobe, Japan (C.S.).
authors.forename: Tomoyoshi
authors.initials: T
authors.lastname: Shigematsu
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Fujinaka
authors.forename: Toshiki
authors.initials: T
authors.lastname: Yoshimine
authors.forename: Hirotoshi
authors.initials: H
authors.lastname: Imamura
authors.forename: Akira
authors.initials: A
authors.lastname: Ishii
authors.forename: Chiaki
authors.initials: C
authors.lastname: Sakai
authors.forename: Nobuyuki
authors.initials: N
authors.lastname: Sakai
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002533:Cerebral Angiography; D002648:Child; D016208:Databases, Factual; D018572:Disease-Free Survival; D057510:Endovascular Procedures; D005260:Female; D006801:Humans; D002532:Intracranial Aneurysm / Q000000981:diagnostic imaging / Q000401:mortality / Q000628:therapy; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D012042:Registries; D015996:Survival Rate
keywords: complications; embolization; endovascular procedures; intracranial aneurysm; treatment outcome; unruptured aneurysm