1. Department of Ophthalmology, Imaizumi Eye Hospital, Koriyama, Japan
2. Department of Ophthalmology, Dokkyo Medical University Saitama Medical Center, Koshigaya, Japan
3. Department of Ophthalmology, Fukushima Medical University, Fukushima, Japan
4. Department of Ophthalmology and Visual Science, Tokyo Medical Dental University, Tokyo, Japan