AIM:To use multifocal electroretinogram(MFERG)to evaluate patients' functional changes of the cone system in the macular center of the retina after taking hydroxychloroquine.

METHODS:Retrospective study. Totally 264 eyes of 132 patients with rheumatoid arthritis examined in the Ophthalmology Department of the First Medical Center of the PLA General Hospital from January 2017 to November 2019 were included in the analysis. According to the length of medication period, patients were divided into 6 groups: 38 cases 76 eyes in group A did not take hydroxychloroquine, 38 cases 76 eyes in group B took hydroxychloroquine for 1a, 17 cases 34 eyes in group C took hydroxychloroquine for 2a, 18 cases 36 eyes in group D took hydroxychloroquine for 3a, 13 cases 26 eyes in group E took hydroxychloroquine for 5a, and 8 cases 16 eyes in group F took hydroxychloroquine for 5a or more and stopped for 3a. The changes of the best corrected visual acuity(BCVA)and the P₁ wave amplitude density value of the first ring retinal response area in the central MFERG were compared among groups.

RESULTS:There was no significant difference in BCVA among groups A to F(F=1.287, P=0.270), BCVA in A-F groups were(0.11±0.11, 0.11±0.10, 0.13±0.10, 0.15±0.10, 0.15±0.11, 0.14±0.10 LogMAR),but the amplitude density of P₁ wave in group A(122.68±1.87nV/deg²)was significantly higher than other groups(115.76±1.71, 113.38±1.51, 109.10±2.52, 94.61±0.78, 94.02±0.91nV/deg², all P<0.05).

CONCLUSION:After long-term administration of hydroxychloroquine, even if the central visual acuity does not change, the results of MFERG examination show that the function of the central cone system of the macular retinal system will decrease with the prolonged administration time, and the visual function cannot recover after stopping taking hydroxychloroquine.