ObjectiveTo evaluate the visual improvement of therapeutic plasma exchange (TPE) for refractory optic neuritis (ON) patients in acute phase.MethodsSeventy-five affected eyes from 44 refractory ON patients with severe visual defect or resistance to high-dose intravenous methylprednisolone (IVMP) therapy, who were admitted to The Chinese PLA General Hospital between January 2015 and August 2016, were recruited and received TPE therapy. Among these patients, 11 were male and 33 were female; the average age was 39.1±13.9; 31 patients had two affected eyes, 13 patients had one affected eye. The course of the disease on the group of patients were more than 2 weeks, and the visual acuity worsened for more than 10 days and continued to deteriorate. TPE treatment was performed on all of the patients. BCVA was recorded before and 24 h after treatment, and the visual function was scored using visual outcome scale (VOS). At the same time, the adverse reactions of TPE treatment were observed. The paired t-test was used to compare the VOS before and after treatment. The correlation between VOS before and after treatment was analyzed by Linear-by-Linear correlation analysis.ResultsAmong 75 affected eyes, the post-therapy VOS 3.89±2.13 was significantly improved from pre-therapy VOS 5.56±1.69 (t=6.77, P＜0.001). Forty-eight of 75 eyes were improved at lease 1 score of VOS, the overall rate of visual improvement was 64.0%. Especially among the eyes with initial vision of light perception, an improved rate of 82.4% was presented. 75.0% in those eyes with initial vision of count fingers and 67.7% in no light perception. Linear-by-Linear correlation analysis showed a significant linear correlation between the scores of VOS before and after TPE treatment (r=0.398, P=0.01). During the course of TPE treatment, 5 patients had mild adverse reactions such as low calcium reaction and allergic reaction and were well controlled after treatment.ConclusionUsing TPE to treat refractory ON in acute phased can improve the visual function of patients.