Objectives: The safety and efficacy of thrombectomy for small-artery occlusions is still controversial. In April 2019, Tron Fx, a stent retriever with an expansion diameter of 2 mm, became reimbursed by health insurance in Japan. We report on cases of thrombectomy for small-artery occlusions performed using this device in seven patients. Methods: The subjects were seven patients who underwent thrombectomy between July 2019 and June 2020 using Tron Fx with 2 mm in diameter. We analyzed clinical

more »

... esults including recanalization and complications. Results: The mean age of the seven patients was 80.1 years, and the subjects included six men. The sites of occlusion were the middle cerebral artery M2 (n = 4), M4 (n = 1), anterior cerebral artery A2 (n = 1), and A3 (n = 1). One of the seven patients had an M2 occlusion that was formed during coil embolization for a ruptured cerebral aneurysm. In five cases, four cases were of primary occlusion and one case was of emboli into a new territory, treating with only Tron Fx 2 mm resulted in thrombolysis in cerebral infarction (TICI) 2b-3 in four cases. There was one case of grade 0, which was M4 occlusion. Finally, TICI 2b-3 were achieved in six of seven cases. No symptomatic intracranial hemorrhage occurred. Symptoms improved in five of six patients, excluding a vascular occlusion that occurred during surgery. Conclusion: Tron Fx with 2 mm diameter can be used safely for small-artery occlusion. The introduction of Tron Fx with 2 mm diameter may contribute to expand indications for thrombectomy for small-artery occlusions.