Doormaal, Pieter Jan van

ImportanceTesting new medical devices or procedures in terms of safety, effectiveness, and durability should follow the strictest methodological rigor before implementation.ObjectivesTo review and analyze studies investigating devices and procedures used in intracranial aneurysm (IA) treatment for methods and completeness of reporting and to compare the results of studies with positive, uncertain, and negative conclusions.Data SourcesEmbase, MEDLINE, Web of Science, and The Cochrane Central Register of Clinical Trials were searched for studies on IA treatment published between January 1, 1995, and the October 1, 2022. Grey literature was retrieved from Google Scholar.Study SelectionAll studies making any kind of claims of safety, effectiveness, or durability in the field of IA treatment were included.Data Extraction and SynthesisUsing a predefined data dictionary and analysis plan, variables ranging from patient and aneurysm characteristics to the results of treatment were extracted, as were details pertaining to study methods and completeness of reporting. Extraction was performed by 10 independent reviewers. A blinded academic neuro-linguist without involvement in IA research evaluated the conclusion of each study as either positive, uncertain, or negative. The study followed Preferring Reporting Items for Systematic Reviews and Meta-Analyses guidelines.Main Outcomes and MeasuresThe incidence of domain-specific outcomes between studies with positive, uncertain, or negative conclusions regarding safety, effectiveness, or durability were compared. The number of studies that provided a definition of safety, effectiveness, or durability and the incidence of incomplete reporting of domain-specific outcomes were evaluated.ResultsOverall, 12 954 studies were screened, and 1356 studies were included, comprising a total of 410 993 treated patients. There was no difference in the proportion of patients with poor outcome or in-hospital mortality between studies claiming a technique was safe, uncertain, or not safe. Similarly, there was no difference in the proportion of IAs completely occluded at last follow-up between studies claiming a technique was effective, uncertain, or noneffective. Less than 2% of studies provided any definition of safety, effectiveness, or durability, and only 1 of the 1356 studies provided a threshold under which the technique would be considered unsafe. Incomplete reporting was found in 546 reports (40%).Conclusions and RelevanceIn this systematic review and meta-analysis of IA treatment literature, studies claiming safety, effectiveness, or durability of IA treatment had methodological flaws and incomplete reporting of relevant outcomes supporting these claims.

Abstract Growth of unruptured intracranial aneurysms (UIAs) is a strong predictor of rupture. Clinical observations suggest that UIAs might grow faster after endovascular treatment than untreated UIAs. There are no head-to-head comparisons of incidence rates of UIAs so far. In this meta-analysis, we compared the incidence rates of growth of untreated UIAs and endovascularly treated UIAs. Methods: We searched PubMed, Embase and Google Scholar for relevant articles and conference abstracts in English, German or French from the inception of the databases to March 2020. We performed a meta-analysis by pooling the incidence rates for growth of aneurysms from natural history studies and endovascular treatment studies. Generalized linear models were used for multivariable adjustment for the prespecified confounders age, size and location. Results: 25 studies (10 describing growth in natural history and 15 reporting growth after endovascular therapy) with 6325 aneurysms were included in the meta-analysis. Median size of the aneurysm was 3.7 mm in the natural history studies and 6.4 mm in endovascular treatment studies (p = 0.001). The pooled incidence rate (IR) of growth was significantly higher in endovascular treatment studies (IR 52 per 1000 person-years, 95% Confidence Interval (CI) 36–79) compared to natural history studies (IR 28 per 1000 person-years, 95% CI 17–46), also after adjustment. Conclusion: The incidence rate of growth in endovascularly treated aneurysms was higher than in natural history studies. However, these results should be viewed in the light of high risk of bias of the individual studies and risk of ecological bias.