AND PURPOSE: Challenging arterial anatomy may prevent timely endovascular treatment (EVT) of acute ischemic stroke (AIS) through transfemoral approach prompting the use of alternative access routes. We determined the crossover rate from femoral to radial access during EVT of AIS-LVO and identified its radiological predictors and clinical outcomes.Retrospective review of all AIS patients who underwent EVT at a single institution from January 2016 to March 2021 was performed. A primary and a secondary radial group depending on whether the radial approach was used primarily or secondary to failure of transfemoral approach was compared.358 consecutive AIS patients with LVO underwent EVT. Radial approach was used primarily in 6 patients (Primary radial, PR) and secondary in 16 patients (Secondary radial, SR). The rate of femoral to radial crossover was 4.7 %. Type III arch and 'Bovine arch' configurations were the most common characteristic in crossover group. Radial access was successful to secure intracranial access in all cases of PR and in 87% of crossover cases. There was no significant difference between the rates of successful reperfusion (53.3% SR, 83% PR, P = .20), NIHSS on discharge (19 SR, 18 PR group, P = .90) or good outcome defined as mRS 0-2 (13.3% SR, to 33.3% PR, P = .29).A radial approach can be considered during EVT of AIS-LVO either primarily or secondarily with a lower threshold to switch from the femoral approach in case of challenging anatomy.Copyright © 2023. Published by Elsevier Inc.