The type of EVT procedure was selected at the discretion of the treating physician. The direct aspiration method and stent retrieval were routinely used. The direct aspiration method refers to a forced arterial suction thrombectomy that uses the Penumbra system (Penumbra Inc., Alameda, CA, USA) [20 (link),21 (link)]. Stent retrieval refers to clot removal by capturing and removing the thrombus with a stent retriever such as the Solitaire AB/FR (Medtronic, Irvine, CA, USA) or Trevo (Stryker, Kalamazoo, MI, USA) [22 (link)-24 (link)]. Balloon guide catheters, adjuvant lytic infusion, intracranial or extracranial angioplasty, and/or stenting were implemented as needed.