Does small aneurysm size predict intraoperative rupture during coiling in ruptured and unruptured aneurysms?

J Stroke Cerebrovasc Dis. 2013 Nov;22(8):1298-303. doi: 10.1016/j.jstrokecerebrovasdis.2012.10.017. Epub 2012 Dec 21.


Background: Aneurysm size is a possible risk factor for intraoperative rupture (IOR) during coiling procedures. We aim to determine if aneurysm size 4 mm or smaller predicts IOR.

Methods: Between January 1997 and August 2010, 689 aneurysms in 595 patients were treated by coiling at a single institution. In all, 41 were excluded from statistical analysis due to missing data leaving 648 aneurysms in 562 patients. Demographic, clinical, and procedural outcomes were collected. We compared the rate of IOR in small aneurysms (≤4 mm) with larger aneurysms (>4 mm). We also compared the rate of IOR in ruptured versus unruptured aneurysms in the above categories.

Results: The overall rate of IOR was 4.9%. Aneurysms 4 mm or smaller were more than twice as likely to rupture on table compared to larger aneurysms (8.7% versus 3.9%; P=.022). Of note, ruptured aneurysms were more prone to IOR compared to unruptured aneurysms (7.0% versus 2.2%; P=.005). Aneurysm size 4 mm or smaller was a risk factor in small, ruptured aneurysms only (P=.019). In addition, unruptured aneurysms that were complicated by IOR were associated with higher rates of 30-day mortality (P<.001).

Conclusions: Aneurysm size 4 mm or smaller is a risk factor for IOR in ruptured but not unruptured aneurysms. This additional risk factor should be considered when planning the management of small, ruptured aneurysms.

Keywords: Cerebral aneurysm; endovascular coiling; intraoperative rupture; predictors of rupture; risk factor; small aneurysm.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Aneurysm, Ruptured / etiology*
  • Aneurysm, Ruptured / mortality
  • Child
  • Endovascular Procedures / adverse effects*
  • Endovascular Procedures / methods*
  • Endovascular Procedures / mortality
  • Female
  • Humans
  • Intracranial Aneurysm / complications
  • Intracranial Aneurysm / pathology*
  • Intracranial Aneurysm / surgery*
  • Intraoperative Complications / mortality
  • Intraoperative Complications / pathology*
  • Male
  • Middle Aged
  • Platelet Aggregation Inhibitors / therapeutic use
  • Predictive Value of Tests
  • Stents
  • Treatment Outcome
  • Young Adult


  • Platelet Aggregation Inhibitors