Joint Shantou International Eye Center Shantou University and the Chinese University of Hong Kong Shantou 515041 Guangdong Province China;
Joint Shantou International Eye Center Shantou University and the Chinese University of Hong Kong Shantou 515041 Guangdong Province China;
Joint Shantou International Eye Center Shantou University and the Chinese University of Hong Kong Shantou 515041 Guangdong Province China;
Joint Shantou International Eye Center Shantou University and the Chinese University of Hong Kong Shantou 515041 Guangdong Province China;
diabetic macular edema; optical coherence tomography; multifocal electroretinography; best-corrected visual acuity;