Safety and Efficacy of Neuroform Atlas Stent-Assisted Coiling of Intracranial Aneurysms in Small Parent Arteries: A Retrospective Study

Abstract

BACKGROUND: Stent-assisted coil embolization is widely accepted for treating intracranial aneurysms with wide necks. The Neuroform Atlas Stent System is the latest microstent that aims to improve coil support, conformability, deliverability, and deployment accuracy. This study aims to analyze the efficacy and safety of the Neuroform Atlas Stent System for treating intracranial aneurysms with wide necks and to present our initial experience. MATERIALS AND METHODS: From November 2019 to October 2020, 360 patients with 386 aneurysms originating from parent arteries of ≤3.0 mm were subjected to stent-assisted coiling using a Low-Profile Visualized Neuroform Atlas stent at a single institution. This study retrospectively reviewed their clinical and radiological data and assessed the risk factors associated with procedure-related complications. The efficacy and safety of the operation were retrospectively analyzed, and the surgical techniques of the Neuroform Atlas Stent System were summarized. This study used the Raymond–Roy (RR) occlusion classification to assess immediate and long-term outcomes after embolization of intracranial aneurysms. RESULTS: The patients’ mean age was 60.2 ± 10.5 years, and 78.1% (281/360) were female. Their mean aneurysm size was 6.9 ± 2.8 mm, mean neck width was 4.6 ± 1.4 mm, and mean dome-to-neck ratio was 1.3 ± 0.2. The anterior communicating artery (116/360, 32.2%) was the most common location for aneurysms. Neuroform Atlas stents were placed in the expected anatomical location in all patients. The study met both primary safety and efficacy endpoints. Follow-up images were available for 306 patients. During follow-up, RR I was achieved in 270 patients (270/306, 88.2%), RR II in 22 patients (22/306, 7.2%), and RR III in 14 patients (14/306, 4.6%). The composite primary efficacy endpoint of complete aneurysm occlusion (RR I) without parent artery stenosis or aneurysm retreatment was achieved in 88.2% of patients. However, 3.1% of patients experienced a primary safety endpoint of major ipsilateral stroke (n = 9) or neurological death (n = 2). CONCLUSIONS: When used with coiling, the Neuroform Atlas stent effectively achieved the main objectives and showed a high complete aneurysm occlusion rate at 12 months, with a technical success rate of 100% and a morbidity rate of 5.4%.