FloWise Flow Diverter for Treatment of Unruptured Wide-Neck Intracranial Aneurysms: A Prospective, Multicenter, Single-Arm, Open-Label, Pivotal Study

Objective: We evaluated the safety and efficacy of a new flow diverter in the treatment of unruptured wide-neck aneurysms. Materials and Methods: Patients who had unruptured intracranial aneurysms with a neck diameter ≥4 mm or dome-to-neck ratio <2 and who met other eligibility criteria were enrolled from seven institutions. The patients were treated with a new flow diverter (FloWise; Taewoong Medical, Seoul, Korea) and followed at 1, 3, 6, and 12 months after treatment. The primary efficacy endpoint was the complete occlusion of the target aneurysm at 12 months. Safety endpoints included ipsilateral stroke (National Institutes of Health Stroke Scale score ≥5), newly developed neurological deficit (modified Rankin Scale score ≥3), death at 30 days, and ≥50% parent artery stenosis or occlusion at the 12-month follow-up. The superiority of FloWise over the predefined reference value (56.7%) was investigated using a one-sided binomial test with a statistical significance of P < 0.025. Results: Seventy patients (59.0 ± 9.9 years; male:female = 16:54) with 93 aneurysms (median diameter, 5.2 mm [range, 1.6– 26.1 mm]; median neck diameter, 4.1 mm [range, 1.2–22.4 mm]) were included. Of these, 69 patients who completed the follow-up as planned constituted the efficacy analysis set. Complete aneurysm occlusion was achieved in 56 target aneurysms (81.2%; 95% confidence interval [CI], 69.9–89.6; P < 0.001). Procedural success and ≥50% aneurysm volume reduction were observed in 69 (100%) and 66 (95.7%; 95% CI, 87.8–99.1) target aneurysms, respectively. No ipsilateral strokes occurred in any of the 70 patients. Serious adverse events occurred in 6 patients; these events were causally related to the treatment in 4 (5.7%) cases and possibly related to the device in 2 (2.9%) cases. Conclusion: FloWise flow diverter is safe and effective for the treatment of unruptured wide-neck aneurysms.