Purpose: Deciding about whether an unruptured intracranial aneurysm (UIA) should be treated or not is challenging because robust data on rupture risks, endovascular treatment complication rates, and treatment success rates are limited. We aimed to investigate how neurointerventionalists conceptually approach endovascular treatment decision-making in UIAs.
Methods: In a web-based international multidisciplinary case-based survey among neurointerventionalists, participants provided their demographics and UIA treatment-volumes, estimated 5-year rupture rates, endovascular treatment complication and success rates and gave their endovascular treatment decision for 15 pre-specified UIA case-scenarios. Differences in estimated 5-year rupture rates, endovascular treatment complication and success rates based on physician and hospital characteristics were evaluated with the Kruskal-Wallis test. Multivariable logistic regression analysis was used to derive adjusted effect size estimates for predictors of endovascular treatment decision.
Results: Two hundred-thirty-three neurointerventionalists from 38 countries participated in the survey (median age 47 years [IQR: 41-55], 25/233 [10.7%] females). The ranges of estimates for 5-year rupture risks, endovascular treatment complication rates, and particularly endovascular treatment success rates were wide, especially for UIAs in the posterior circulation. Estimated 5-year rupture risks, endovascular treatment complication and success rates differed significantly based on personal and institutional endovascular UIA treatment volume, and all three estimates were significantly associated with physicians' endovascular treatment decision.
Conclusion: Although several predictors of endovascular treatment decision were identified, there seems to be a high degree of uncertainty when estimating rupture risks, treatment complications, and treatment success for endovascular UIA treatment. More data on the clinical course of UIAs with and without endovascular treatment is needed.
Keywords: Coiling; Complications; Unruptured intracranial aneurysm.