A newly-developed flow diverter (flowise) for internal carotid artery aneurysm: Results of a pilot clinical study

Objective: We report the results of a pilot clinical study that evaluated the safety and efficacy of a newly-developed, retrievable flow diverter (FloWise; Taewoong Medical) for the treatment of internal carotid artery (ICA) aneurysm. Materials and Methods: A total of 10 patients were enrolled. Inclusion criteria were 1) unruptured aneurysm with a dome size of ≥ 8 mm and a neck size of ≥ 4 mm at the ICA, or 2) two or more unruptured aneurysms of any size able to be spanned by a single FloWise at the ICA. Co-primary effectiveness end points were technical success of FloWise placement, and a 50% or greater decrease in aneurysm volume at the 6-month follow-up angiogram. The primary safety end point was the new development of neurological deficits persisting for more than 1-month post-treatment. Results: Ten patients harboring 14 ICA aneurysms (median diameter, 9.4 mm; range, 2.3-31.0 mm) were enrolled between January 2016 and July 2017. FloWise placement was successful in all patients. There were no newly-developed neurological deficits during the 6-month clinical follow-up period. One patient did not receive follow-up imaging due to pregnancy. Nine patients with 12 aneurysms received a 6-month angiographic follow-up. Ten aneurysms (83.3%) showed decreases in volume greater than 50% (mean volume decrease, 82.8 ± 32.9%), of which 8 (66.7%, 95% confidence interval, 35.4-98.0%) showed complete occlusion. One patient was retreated due to mass symptom aggravation. Conclusions: In this pilot study, FloWise appeared to be safe and effective for ICA aneurysm treatment. A prospective multicenter study to validate the effectiveness and safety of FloWise would be worthwhile.