Background Flow Diverter Devices (FDD) have been shown to be effective in the treatment of side-wall, wide-necked IA. However, the use of these devices to treat bifurcation lesions remains to be validated. MCA wide-neck IA. Represents a frequent finding in our daily practice and constitutes a real challenge for endovascular conventional approach requiring special considerations: (Balloon Assisted Coiling, Stent and Coils). Few studies have been conducted on the safety and efficacy using FDD for the treatment of MCA bifurcation aneurysms.

Objective To describe our experience using FDD in the treatment of MCA IA. Feasibility, Safety and Efficacy are reported. Radiological (Complete Occlusion rate) and, Clinical findings were registered immediately after implantation and during follow-up. Factors associated with incomplete occlusion were analyzed.

Methods We retrospectively analyzed a subgroup of patients with MCA IA treated using FDD in our data-base. We describe here clinical, anatomical and angiographic variables. Procedural technical success, adverse events and Follow Up were registered. Complete Occlusion rate was defined using O’Kelly-Marotta classification.

Results From June 2012 to April 2020 a total of 62 patients with 64 aneurysms were selected in this series. All cases under DAPT and GA. Giant: 11, Large: 9 and Small lesions: 44 (68%). Fourteen cases with history of SAH. A total of 71 devices were implanted (PED Classic :6, PED Flex: 21, PED Flex-shield:18 and FRED: 26). A mean of 1.1 device per aneurysm. In all cases planned but two (PED Classic) FD finally could be implanted i.e., Technical success of 97%. Radiological FU available in 38/64 (60%). Mid-long term Follow-up (mean: 29 months). showed a complete occlusion rate of 78%. MCA major branch with flow reduction or acute occlusion was evidenced in 13 cases (20%). Of these, six cases were solved using IIb-IIIa GPI and seven cases (10.9%) remain occluded and evolved with neurological clinical deficit.

Conclusion The use of FD´s technology for treatment of MCA bifurcations IA should be reserved for highly selected patients otherwise considered un-treatable with conventional endovascular approaches. Learning curve, accurate DAPT and intraprocedural arterial blood pressure supervision must be considered as key factors to avoid undesired thrombo-embolic complications. The real role of FD´s and its comparison with endosaccular approaches remain to be defined in posterior and controlled studies.

Disclosures B. Pabon Guerrero: None. M. Patino Hoyos: None. J. Gutierrez Banos: None. V. Torres: None. J. Mejia: None.