Comparison of Neurologic and Radiographic Outcomes with Solitaire versus Merci/Penumbra Systems for Acute Stroke Intervention

Background and Purpose. The Solitaire Flow Restoration was approved by the FDA in 2012 for mechanical thrombolysis of proximal occlusion of intracranial arteries. To compare the Solitaire FR device and the Merci/Penumbra (previously FDA approved) systems in terms of safety, clinical outcomes, and efficacy including radiographic brain parenchymal salvage. Methods. Thirty-one consecutive patients treated with the Solitaire and 20 patients with comparable baseline characteristics treated with Merci or Penumbra systems were included in the study. Primary outcome measures included recanalization rate and modified Rankin Scale score at followup. Secondary outcomes included length of procedure, incidence of symptomatic intracranial hemorrhage, 90-day mortality, and radiographic analysis of percentage area salvage. Results. Compared with the Merci/Penumbra group, the Solitaire group showed a statistically significant improvement in favorable outcomes (mRS ≤ 2) (69% versus 35%, P = 0.03) and symptomatic ICH rate (0 versus 15%, P = 0.05) with a trend towards higher recanalization rates (93.5% versus 75%, P = 0.096) and shorter length of procedure (58.5 min versus 70.8 min, P = 0.08). Radiographic comparison also showed a significantly larger area of salvage in the Solitaire group (81.9% versus 71.9%, P = 0.05). Conclusion. Our study suggests that the Solitaire system allows faster, safer, and more efficient thrombectomy than Merci or Penumbra systems.