1. Department of Ophthalmology and Visual Science, Seoul St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.
2. Department of Ophthalmology, Ewha Mokdong Hospital, Ewha Womans University School of Medicine, Seoul, Korea.
3. Department of Ophthalmology, Yeouido St. Mary's Hospital, The Catholic University of Korea College of Medicine, Seoul, Korea.