Korean J Radiol.  2019 Mar;20(3):505-512. 10.3348/kjr.2018.0421.

A Newly-Developed Flow Diverter (FloWise) for Internal Carotid Artery Aneurysm: Results of a Pilot Clinical Study

• Kim BM
• Park KY
• Lee JW
• Chung J
• Kim DJ
• Kim DI

• KMID: 2438281
• DOI: http://doi.org/10.3348/kjr.2018.0421

Abstract

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.

Keyword

Intracranial aneurysm; Flow diversion; New device

MeSH Terms

Aneurysm*
Carotid Artery, Internal*
Clinical Study*
Follow-Up Studies
Humans
Intracranial Aneurysm
Neck
Pilot Projects
Pregnancy
Prospective Studies

Figure

• 

  Fig. 1 FloWise (Taewoong Medical) flow diverter.A. Spot image of FloWise and Pipeline Flex (Medtronic) flow diverters. B. Image of partially deployed FloWise stent. Note distal tip of stent-loading delivery wire is pre-shaped in J configuration. C. Schematic drawing of FloWise design.

• 

  Fig. 2 52-year-old woman presented with large aneurysm at right ICA paraclinoid segment.A. Right carotid angiogram shows 15.4-mm-sized aneurysm at ICA paraclinoid segment. B. Spot image during FloWise deployment. Note that distal tip of FloWise loading delivery wire is pre-shaped in J configuration (arrow). C. Spot image 10 minutes after FloWise deployment shows that contrast materials still remain in aneurysm sac. D. 6-month follow-up angiogram shows complete occlusion of aneurysm. E. Initial T2-weighted MR image shows large aneurysm (arrow) at intradural portion of right ICA. F. 12-month follow-up T2-weighted MR image shows disappearance of aneurysm. ICA = internal carotid artery, MR = magnetic resonance

• 

  Fig. 3 57-year-old woman presenting with recurrent aneurysms 10 years after wrapping of giant aneurysm at right ICA paraclinoid segment.A. Initial right carotid angiogram shows giant aneurysm. B. Right carotid angiogram 10 years after initial treatment shows large aneurysm at supraclinoid segment and partially thrombosed giant aneurysm at paraclinoid segment. C. Right carotid angiogram just after three FloWise stent placements. D. Aneurysm flow before (left) and after (right) shows marked flow diversion effect. Note inflow zone is shifted from distal to proximal neck and inflow jets do not reach aneurysm dome. Arrows in the sac and their magnitude indicate flow direction and velocity, respectively. E. Flat-panel computed tomography image immediately after treatment with three overlapping FloWise stents. Arrowheads indicate outline of partially thrombosed giant aneurysm at paraclinoid segment of right ICA. F. 6-month follow-up angiogram after treatment with three FloWise stents shows complete occlusion of giant aneurysm at paraclinoid segment and decrease in size of large aneurysm at supraclinoid segment. Degree of stenosis between two aneurysms was aggravated, but patient remained asymptomatic. G. 12-month follow-up angiogram shows greater decrease in size of aneurysm at supraclinoid segment and slight improvement of stenosis.

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