1. Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
2. Nune Eye Hospital, Seoul, Korea.
3. Department of Ophthalmology and Visual Science, Yeouido St. Mary's Hospital, College of Medicine, The Catholic University of Korea, Seoul, Korea.
4. Catholic Institute for Visual Science, College of Medicine, The Catholic University of Korea, Seoul, Korea.