Long-term clinical and angiographic follow-up results of the dual-layer flow diverter device (FRED) for the treatment of intracranial aneurysms in a multicenter study

Neuroradiology. 2021 Jun;63(6):943-952. doi: 10.1007/s00234-020-02627-1. Epub 2021 Jan 3.


Purpose: Our aim was to determine the long-term safety and efficacy of the Flow Re-Direction Endoluminal Device (FRED) in this multicenter study with prospective design.

Materials-method: This study included 136 consecutive patients with 155 aneurysms treated between March 2013 and June 2016 in 10 centers. Twenty-two (16.2%) patients presented with rupture of the index aneurysm. Large/giant aneurysms comprised 1/3 of the cohort. Adjuvant coil use during the treatment was 15.5%. The effectiveness measure in the study was the percentage of aneurysms with stable occlusion at follow-up.

Results: Vascular imaging follow-up was performed at least once in 131/136 (96.3%) patients with 148/155 (95.5%) aneurysms up to 75 months (mean: 37.3 months; median: 36 months according to latest follow-up), and 102/155(65.8%) aneurysms in 90/136 (66.2%) patients had ≥ 24-month control. According to the latest controls, the overall stable occlusion rate was 91.9% (95% CI, 87.5 to 96.3%). Three out of 148 aneurysms with follow-up were retreated (2%, 95% CI 0.0 to 4.3%). Adverse events were noted in 19/136 (14%, 95% CI, 9 to 21%) patients with a morbidity of 1.5% (95% CI, 0.0 to 3.5%). Mortality was 1/136 (0.7%, 95% CI, 0.02 to 2.2%) and was unrelated to aneurysm treatment. In-stent stenosis (ISS) was detected in 10/131 of the patients with follow-up (7.6%, 95% CI; 3.1 to 12.2%), only one being symptomatic. No adverse events have occurred in any of the patients with follow-up after 24 months, except the one resulting from ISS.

Conclusion: In the treatment of cerebral aneurysms which were candidates for flow diversion technique, this study showed long-term efficacy of FRED with good safety and occlusion rates.

Keywords: Cerebral aneurysm; Endovascular treatment; Flow Re-Direction Endoluminal device = FRED; Flow diversion.

Publication types

  • Multicenter Study

MeSH terms

  • Cerebral Angiography
  • Embolization, Therapeutic*
  • Endovascular Procedures*
  • Follow-Up Studies
  • Humans
  • Intracranial Aneurysm* / diagnostic imaging
  • Intracranial Aneurysm* / therapy
  • Prospective Studies
  • Retrospective Studies
  • Stents
  • Treatment Outcome