Objective: To investigate the feasibility of parameter-optimized magnetic resonance imaging (MRI) as the first choice for imaging examination in patients with acute ischemic stroke (AIS), and to assess the effects of quality improvement (QI) measures on shortening the door-to-needle time (DNT). Methods: A retrospective case-control study was conducted. A total of 69 AIS patients hospitalized at the Department of Neurology of the People's Hospital of Wuzhou from August 2015 to July 2018 were enrolled in the study, and the head MRI was used as the first choice for imaging examination. All patients received the intravenous thrombolytic therapy with recombinant tissue plasminogen activator (rt-PA). Patients with AIS undergoing intravenous thrombolysis from August 2015 to March 2017 were included in the control group, and those receiving intravenous thrombolysis after QI measures from April 2017 to July 2018 were included in the experimental group. QI included informing the stroke team in advance by emergency physicians, treatment process changing from serial procedure to the parallel one, optimization of MRI scanning parameters, and use of rapid test instruments. The MRI scanning time was compared between the two groups. The DNT of the two groups was compared, and paired-samples t test was used. The proportion of patients who underwent MRI scan and DNT<60 min was compared between the two groups, and the χ² test was used. Results: Compared with the control group, the proportion of patients undergoing MRI scan in the experimental group was increased (82% vs 58%, χ²=4.58, P=0.032); MRI scanning time was shortened (4 min 37 s vs 10 min 21 s); DNT (min) was shortened (59.32±10.19 vs 93.48±24.81, t=7.189, P<0.01); and the proportion of patients with DNT<60 min was significantly increased (68% vs 6%, χ²=27.190, P<0.01). Conclusion Parameter-optimized MRI as the first choice for imaging examination in AIS patients with the onset time <4.5 h was feasible, and the DNT was significantly shortened by QI measures.