Ruptured posterior circulation aneurysms: epidemiology, patterns of care, and outcomes from the Swiss SOS national registry

Acta Neurochir (Wien). 2019 Apr;161(4):769-779. doi: 10.1007/s00701-019-03812-9. Epub 2019 Jan 25.


Background: The treatment of ruptured posterior circulation aneurysms remains challenging despite progresses in the endovascular and neurosurgical techniques.

Objective: To provide epidemiological characterization of subjects presenting with ruptured posterior circulation aneurysms in Switzerland and thereby assessing the treatment patterns and neurological outcomes.

Methods: This is a retrospective analysis of the Swiss SOS registry for patients with aneurysmal subarachnoid hemorrhage. Patients were divided in 3 groups (upper, lower, and middle third) according to aneurysm location. Clinical, radiological, and treatment-related variables were identified and their impact on the neurological outcome was determined.

Results: From 2009 to 2014, we included 264 patients with ruptured posterior circulation aneurysms. Endovascular occlusion was the most common treatment in all 3 groups (72% in the upper third, 68% in the middle third, and 58.8% in the lower third). Surgical treatment was performed in 11.3%. Favorable outcome (mRS ≤ 3) was found in 56% at discharge and 65.7% at 1 year. No significant difference in the neurological outcome were found among the three groups, in terms of mRS at discharge (p = 0.20) and at 1 year (p = 0.18). High WFNS grade, high Fisher grade at presentation, and rebleeding before aneurysm occlusion (p = 0.001) were all correlated with the risk of unfavorable neurological outcome (or death) at discharge and at 1 year.

Conclusions: In this study, endovascular occlusion was the principal treatment, with a favorable outcome for two-thirds of patients at discharge and at long term. These results are similar to high volume neurovascular centers worldwide, reflecting the importance of centralized care at specialized neurovascular centers.

Keywords: Aneurysmal subarachnoid hemorrhage; Endovascular procedures; Hydrocephalus; Intracranial aneurysms; Intracranial vasospasm; Posterior circulation; Ruptured aneurysms.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Aged, 80 and over
  • Aneurysm, Ruptured / epidemiology
  • Aneurysm, Ruptured / surgery*
  • Embolization, Therapeutic / methods
  • Female
  • Humans
  • Intracranial Aneurysm / epidemiology
  • Intracranial Aneurysm / surgery*
  • Male
  • Middle Aged
  • Neurosurgical Procedures / methods
  • Prevalence
  • Registries
  • Retrospective Studies
  • Switzerland / epidemiology
  • Treatment Outcome
  • Young Adult