Treatment of cerebral aneurysms with the FRED Jr flow-diverting stent: A case series and meta-analysis

Background: With the development of the Flow Re-Direction Endoluminal Device Junior (FRED Jr), treatment of distal aneurysms and/or aneurysms with small parent vessels has become a viable option. Objectives: To assess the efficacy and safety of FRED Jr in the treatment of distal aneurysms with small parent vessels. Methods: This is a single center retrospective study and meta-analysis of patients treated with FRED Jr for intracranial aneurysms. The primary outcome was complete aneurysm occlusion at final follow-up. Secondary outcomes included stroke rates, mortality rates, need for retreatment and clinical outcomes. Results: There were a total of 7 patients with 7 aneurysms treated with FRED Jr. Mean aneurysm neck, width, height, and parent artery diameter were 2.6 ± 0.8 mm, 3.1 ± 0.9 mm, 2.5 ± 1.0 mm, and 1.8 ± 0.6 mm respectively. The complete occlusion rate was 57.1 % at 6 months, and favorable outcome (mRS 0–2) was observed in all patients in follow-up. Stroke complication occurred in none of the patients. Seven studies from 1360 articles were identified for inclusion in the meta-analysis, comprising 227 patients with 244 aneurysms treated with FRED Jr. Mean aneurysm height, width, neck and parent artery diameter were 6.9 ± 3.3 mm (pooled=5.6 [<0.1–11.47] mm), 6.6 ± 2.2 mm (pooled=6.6 [4.2–9.1] mm), 4.4 ± 1.4 mm (pooled=4.1 [3.3 −4.9] mm), and 2.0 ± 0.2 mm (pooled=2.1 [1.7–2.5]), respectively. At final follow-up, the pooled complete occlusion and complication rates were 69.9 % and 0 %, respectively. Conclusion: FRED Jr demonstrated moderate efficacy and good safety in the treatment of distal aneurysms with small parent vessels at mid-term follow-up.