Multicenter Experience with FRED Jr Flow Re-Direction Endoluminal Device for Intracranial Aneurysms in Small Arteries

Abstract

Background and purpose: Flow diverters are emerging as an endovascular treatment alternative for proximally located intracranial aneurysms. However, treatment of aneurysms at and beyond the circle of Willis is not well-established. We assessed the clinical safety and efficacy of the Flow Re-Direction Endoluminal Device Jr (FRED Jr) dedicated to small-vessel diameters between 2.0 and 3.0 mm.

Materials and methods: This was a multicenter observational clinical study of 42 patients with 47 aneurysms treated by a flow-direction technique with the FRED Jr. The primary end point for clinical safety was the absence of death, major or minor stroke, and TIA. The primary end point for treatment efficacy was complete and near-complete occlusion according to the O'Kelly-Marotta grading scale at follow-up after 1, 6, and 12 months.

Results: The FRED Jr deployment was technically successful in all cases. In 39/42 (93%) patients, the primary safety end point was reached; in the 3 remaining patients, 1 disabling ischemic stroke, 1 minor stroke with complete recovery at discharge, and 1 TIA were observed. Two asymptomatic, completely reversible side-branch occlusions occurred. Angiographic (DSA or flat panel CT) and clinical follow-up were available after 1 month in 41/47 (87%), 6 months in 27/47 (57%), and 12 months in 11/47 (23%) aneurysms. The primary efficacy end point was reached at 1 month in 27/41 (66%), at 6 months in 21/27 (78%), and at 12 months in 11/11 (100%) aneurysms.

Conclusions: Deployment of the FRED Jr is safe and effective in the treatment of intracranial aneurysms located in small vessels.

Fig 1.

Patient 6 with a bifurcation aneurysm of the middle cerebral artery (3D-DSA, A) and after implantation of a FRED Jr in the M1 and superior MCA trunk (arterial FPCT, B). At 3-month follow-up, complete occlusion was observed (venous FPCT, C).

Fig 2.

Patient 23 with an A2/A3 aneurysm of the anterior cerebral artery (A), and after deployment of a FRED Jr (B). At 6-month follow-up, complete occlusion was observed (C).

Fig 3.

Patient 35 with a partially thrombosed giant aneurysm originating from the posterior cerebellar artery (T2, A; 3D-DSA, B). After deployment of a FRED Jr (arrowheads indicating the flow-diverting working zone, arrow pointing to the tip of the delivery wire, bracket showing the delivery wire markers where normally the proximal stent markers are compressed within the microcatheter, asterisk indicating the tip of the microcatheter; C), the aneurysm filling is reduced (D). At 12-month follow-up, the aneurysm is almost completely shrunken (TOF E; T2, F).