Rui Hua1, Kai Yao2, Limin Liu3, Jun Li2. 1. Department of Ophthalmology, First Hospital of China Medical University, No.155, Nanjingbei Street, Heping District, Shenyang, Liaoning Province, People's Republic of China. woodshua@126.com. 2. Department of Ophthalmology and Visual Science, Yale University School of Medicine, New Haven, CT, 06510, USA. 3. Department of Ophthalmology, First Hospital of China Medical University, No.155, Nanjingbei Street, Heping District, Shenyang, Liaoning Province, People's Republic of China.