We read with great interest the paper ‘Contour Neurovascular System for endovascular embolization of cerebral aneurysms: a multicenter cohort study of 10 European neurovascular centers’ by Griessenauer and colleagues, reporting a large series of 279 patients, prospectively collected and retrospectively reviewed without independent analysis of clinical outcome or anatomical results.1 Most aneurysms treated were unruptured (83.2%), 11.1% were treated at the acute stage of subarachnoid hemorrhage (SAH), and 5.7% after a prior SAH. The three most frequent locations were middle cerebral artery (MCA) in 26.5%, anterior communicating artery (Acom) in 26.2%, and basilar tip in 23.3%. Thromboembolic and hemorrhagic complications occurred in 6.8% and 0.4% of aneurysms, respectively, and mRS at discharge was between 3 and 5 in 2.7% of patients and 6 (death) in 1.5%. At final follow-up (median 12 months), the authors reported complete aneurysm occlusion in 63.2% and neck remnant in 28.3%.

This paper is interesting as it reports the first large, multicenter series dedicated to aneurysm treatment with Contour (Stryker, Kalamazoo, Michigan, USA). However, the study has several methodological limitations: (1) data quality and completeness were not controlled by independent clinical research assistants; (2) clinical outcomes and adverse events were not independently evaluated by a Clinical Event Committee (CEC); and (3) anatomical results were not independently evaluated by a core lab.

Clearly, new devices used in the INR field deserve high-quality, independent evaluation to ensure that the device is safe and efficacious for patients. …