Angiographic results of surgical or endovascular treatment of intracranial aneurysms: a systematic review and inter-observer reliability study

Anass Benomar, Behzad Farzin, David Volders, Guylaine Gevry, Justine Zehr, Robert Fahed, William Boisseau, Jean Christophe Gentric, Elsa Magro, Lorena Nico, Daniel Roy, Alain Weill, Charbel Mounayer, François Guilbert, Laurent Létourneau-Guillon, Gregory Jacquin, Chiraz Chaalala, Marc Kotowski, Thanh N. Nguyen, David KallmesPhil White, Tim E. Darsaut, Jean Raymond

Research output: Contribution to journalArticlepeer-review


Purpose: Results of surgical or endovascular treatment of intracranial aneurysms are often assessed using angiography. A reliable method to report results irrespective of treatment modality is needed to enable comparisons. Our goals were to systematically review existing classification systems, and to propose a 3-point classification applicable to both treatments and assess its reliability. Methods: We conducted two systematic reviews on classification systems of angiographic results after clipping or coiling to select a simple 3-category scale that could apply to both treatments. We then circulated an electronic portfolio of angiograms of clipped (n=30) or coiled (n=30) aneurysms, and asked raters to evaluate the degree of occlusion using this scale. Raters were also asked to choose an appropriate follow-up management for each patient based on the degree of occlusion. Agreement was assessed using Krippendorff’s α statistics (αK), and relationship between occlusion grade and clinical management was analyzed using Fisher’s exact and Cramer’s V tests. Results: The systematic reviews found 70 different grading scales with heterogeneous reliability (kappa values from 0.12 to 1.00). The 60-patient portfolio was independently evaluated by 19 raters of diverse backgrounds (neurosurgery, radiology, and neurology) and experience. There was substantial agreement (αK=0.76, 95%CI, 0.67–0.83) between raters, regardless of background, experience, or treatment used. Intra-rater agreement ranged from moderate to almost perfect. A strong relationship was found between angiographic grades and management decisions (Cramer’s V: 0.80±0.12). Conclusion: A simple 3-point scale demonstrated sufficient reliability to be used in reporting aneurysm treatments or in evaluating treatment results in comparative randomized trials.

Original languageEnglish (US)
Pages (from-to)1511-1519
Number of pages9
Issue number9
StatePublished - Sep 2021


  • Classification system
  • Digital subtraction angiography
  • Inter-rater reliability
  • Intracranial aneurysms

ASJC Scopus subject areas

  • Radiology Nuclear Medicine and imaging
  • Clinical Neurology
  • Cardiology and Cardiovascular Medicine


Dive into the research topics of 'Angiographic results of surgical or endovascular treatment of intracranial aneurysms: a systematic review and inter-observer reliability study'. Together they form a unique fingerprint.

Cite this