Clinical Trial of the New Stent Retriever Tron FX for both Proximal and Distal Intracranial Large Vessel Occlusions.

Background: In all of randomized controlled trials of mechanical thrombectomy, the target vessels were proximal. Herein we report a clinical trial of the Tron FX stent retriever, including the smallest size of 2/15 mm for distal intracranial large vessel occlusion (LVO).
Objective: Eligible patients presented within 8 h of onset with proximal or distal LVOs, and the Tron FX 4/20 mm or 2/15 mm were used as the first-line device.
Methods: The primary endpoints were rate of modified Thrombolysis in Cerebral Infarction (mTICI) grade 2a-3 immediately after using Tron FX only, and mortality rate 90 d. We compared the outcomes between sizes 4/20 and 2/15 mm.
Results: The clinical trial was conducted in 50 cases, of which 44% presented with distal LVO and 15 cases were treated using only Tron FX 2/15 mm. The overall rate of mTICI grade 2a-3 was 80.0% (75.8% with Tron FX 4/20 mm, and 86.7% with 2/15 mm), and a 90-day modified Rankin Scale ≤ 2 or improvement of National Institute of Health Stroke Scale after thrombectomy ≥ 10 was achieved in 66.7% of cases (61.3% with Tron FX 4/20 mm, and 80.0% with 2/15 mm). The overall 90-day mortality rate was 8.0%, and symptomatic intracranial hemorrhage within 24 h occurred in 2.0% of cases.
Conclusion: In this clinical trial using the Tron FX, which included the size of 2/15 mm for distal LVO, its efficacy was similar and its safety was superior compared with previous studies.
Competing Interests: Declaration of Competing Interest All authors who are members of the Japan Neurosurgical Society (JNS) have registered online self-reported conflicts of interest disclosure statement forms through the website for JNS members. H. Imamura received Speakers’ Bureau/Honoraria from Medtronic Co. N. Sakai received Speakers’ Bureau/Honoraria from JIMRO Co., Johnson & Johnson K.K., Medtronic Co,. Penumbra Co., and Stryker Japan K.K., and research funding from Japanese Ministry of Health, Labour and Welfare and Terumo Co. H. Yamagami received Speakers’ Bureau/Honoraria from Terumo Co., Biomedical Solutions Co., and Otsuka Pharmaceutical Co., and research funding from JIMRO Co. Y. Matsumoto received Speakers’ Bureau/Honoraria from Medtronic Co., Takeda Pharmaceutical Co., Otsuka Pharmaceutical Co., GE Health care Japan Co., Stryker Co., Century Medical Co., Medico's Hirata Co., and Fuji systems Co. S. Yoshimura received Speakers’ Bureau/Honoraria from Boehringer-Ingelheim Co., Daiichi Sankyo Co., Bayer Co., and Bristol-Meyers Squibb Co., and research funding from Otsuka Pharmaceutical Co. and Medtronic Co. Y. Matsumaru received Speakers’ Bureau/Honoraria from Medtronic Co., Stryker Co., Terumo Co., Johnson & Johnson Co., Kaneka Co., JIMRO Co., and Biomedical Solutions Co. Other authors have no conflict of interest related to this manuscript.
(Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)