title: Surgical Clipping of Very Small Unruptured Intracranial Aneurysms: A Multicenter International Study.
abstract: BACKGROUND
  Treatment of very small unruptured intracranial aneurysms (VSUIAs, defined as ≤3 mm) can be indicated in selected circumstances. The feasibility and outcomes of endovascular therapy for VSUIAs have been recently published; however, the efficacy and complication rate of surgical clipping has not been reported in any large series to date.
  
  
  OBJECTIVE
  We conducted a multicenter study to examine surgical outcomes for VSUIAs.
  
  
  METHODS
  All consecutive patients undergoing surgery for a VSUIA in 4 neurosurgical centers between October 2001 and December 2012 were retrospectively analyzed.
  
  
  RESULTS
  In the study, 183 patients (128 women, mean age 51.3 years) were treated with 190 procedures for a total of 228 aneurysms. Most were anterior circulation aneurysms (n = 215). The majority were directly clipped (n = 222, 97.4%), with coagulation or wrapping in the remainder. After 1 reoperation for incomplete clipping, postoperative imaging of 225 aneurysms confirmed complete occlusion in 221 (98.2%), 1 neck remnant (0.44%), and 3 partial occlusions (1.3%). Mortality was 0%. Early postoperative neurological deficit developed in 12 patients (6.6%); posterior circulation location was a significant risk factor for early neurological deficit (P < .001). Middle cerebral artery aneurysms had the lowest rate of postoperative deficits at 1.5% (P = .023). After the initial 30-day perioperative period, all deficits related to treatment of posterior circulation aneurysms recovered; overall neurological morbidity decreased to 2.7% with no mortality.
  
  
  CONCLUSIONS
  VSUIA clipping is highly effective and is associated with a low morbidity rate. For VSUIAs selected for treatment, our data support surgical clipping as the modality of choice.
authors: *Department of Neurosurgery, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium;‡Department of Neurosurgery, University of Illinois at Chicago, Chicago, Illinois;§Department of Neurosurgery, Helsinki University Central Hospital, Helsinki, Finland;¶Department of Neurosurgery, Hôpital Cantonal Universitaire de Genève, Geneva, Switzerland;‖Department of Emergency Medicine, Erasme Hospital, Université Libre de Bruxelles, Brussels, Belgium.
authors: Michaël
authors: M
authors: Bruneau
authors: Sepideh
authors: S
authors: Amin-Hanjani
authors: Päivi
authors: P
authors: Koroknay-Pal
authors: Philippe
authors: P
authors: Bijlenga
authors: Behnam Rezai
authors: BR
authors: Jahromi
authors: Hanna
authors: H
authors: Lehto
authors: Riku
authors: R
authors: Kivisaari
authors: Karl
authors: K
authors: Schaller
authors: Fady
authors: F
authors: Charbel
authors: Sajeel
authors: S
authors: Khan
authors: Christian
authors: C
authors: Mélot
authors: Mika
authors: M
authors: Niemela
authors: Juha
authors: J
authors: Hernesniemi
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D038622:Internationality; D002532:Intracranial Aneurysm / Q000175:diagnosis* / Q000601:surgery*; D008297:Male; D008866:Microsurgery / Q000295:instrumentation* / Q000379:methods*; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D013525:Surgical Instruments / Q000706:statistics & numerical data*; D016896:Treatment Outcome; D055815:Young Adult