Novel use of a stent retriever as a distal filler protection device for prevention of secondary embolization.

Distal embolus due to mechanical thrombectomy is a frequent complication and directly results in a poor prognosis. Therefore, it is important to decrease distal embolus as much as possible in mechanical thrombectomy. EmboTrap III may be useful as a filter to prevent distal embolus in patients with a large volume of thrombus. Here, we report the results of one suggestive case and we also provide experimental data from a vessel model. The patient was a 78-year-old female who was admitted to hospital as an emergency case with chief complaints including dysarthria and left hemiplegia, including facial paralysis. She was diagnosed as large vessel occlusion-acute ischemic stroke with right tandem lesions by workup and underwent mechanical thrombectomy. A large volume of secondary thrombus due to flow stasis was assumed based around the occlusion site, and worsening of neurological symptoms was a concern due to distal embolus caused by recanalization of the cervical internal carotid artery. The SEIMLESS technique was performed under distal protection using EmboTrap III. There was no distal embolus or deterioration of neurological symptoms, and a good prognosis was achieved. This outcome suggests that PTA under distal protection using EmboTrap III may be useful for prevention of distal embolus.