Determinants of Gadolinium-Enhancement of the Aneurysm Wall in Unruptured Intracranial Aneurysms

Neurosurgery. 2018 Oct 1;83(4):719-725. doi: 10.1093/neuros/nyx487.

Abstract

Background: Recent studies suggest that gadolinium-enhancement of the aneurysm wall may reflect aneurysm wall inflammation, which might increase the risk of aneurysm growth or rupture.

Objective: To determine the prevalence of gadolinium-enhancement and its determinants in patients with predominantly small (<7 mm) unruptured intracranial aneurysms.

Methods: We performed 3 T MRI aneurysm wall imaging in patients with ≥1 unruptured aneurysm. With Poisson regression analysis, we calculated crude and adjusted risk ratios (RRs) with 95% confidence intervals (CI) to assess determinants of gadolinium-enhancement.

Results: Gadolinium-enhancement was observed in 25/79 patients (32%; 95% CI: 21%-42%) and 26/89 aneurysms (29%; 95% CI: 20%-39%). With aneurysms 1.0-2.9 mm as reference, RRs were 4.6 (95% CI: 0.6-36.5) for 3.0 to 4.9 mm, 9.4 (95% CI: 1.3-67.2) for 5.0 to 6.9 mm, and 14.8 (95% CI: 2.1-104.6) for ≥7.0 mm. With internal carotid artery as reference, RRs adjusted for aneurysm size were 3.6 (95% CI: 1.1-11.4) for posterior communicating artery and 3.0 (95% CI: 1.0-8.6) for middle cerebral artery. RRs were 0.8 (95% CI: 0.4-1.8) for acetylsalicylic acid use, 0.9 (95% CI: 0.5-1.8) for statin use, 1.4 (95% CI: 0.7-2.8) for hypertension, 0.9 (95% CI: 0.4-1.8) for previous smoking, 0.9 (95% CI: 0.3-2.6) for never smoking, and 1.4 (95% CI: 0.7-2.7) for irregular aneurysm shape.

Conclusion: Approximately one-third of patients had gadolinium-enhancement. Because aneurysm size is the strongest determinant of gadolinium-enhancement and also an established predictor for aneurysm growth and rupture, prospective studies with serial imaging need to investigate if gadolinium-enhancement predicts aneurysm growth and rupture.

MeSH terms

  • Aged
  • Carotid Artery, Internal / diagnostic imaging
  • Circle of Willis / diagnostic imaging
  • Cross-Sectional Studies
  • Female
  • Gadolinium*
  • Humans
  • Imaging, Three-Dimensional / methods*
  • Intracranial Aneurysm / diagnostic imaging*
  • Intracranial Aneurysm / epidemiology
  • Magnetic Resonance Imaging / methods*
  • Male
  • Middle Aged
  • Middle Cerebral Artery
  • Prospective Studies
  • Risk Factors

Substances

  • Gadolinium