1. Department of Ophthalmology, National Medical Center, 245 Euljiro, Jung-gu, Seoul 100-799, Republic of Korea
2. Department of Ophthalmology, Seoul Metropolitan Government Seoul National University Boramae Medical Center, No. 395 Shindaebang-2-dong, Dongjak-gu, Seoul 156-707, Republic of Korea
3. Department of Ophthalmology, Seoul National University College of Medicine, 103 Daehak-ro, Jongno-gu, Seoul 110-799, Republic of Korea
4. Sensory Organs Institute, Medical Research Center, Seoul National University, 103 Daehak-ro, Jongno-gu, Seoul 110-799, Republic of Korea