Toshihiko Matsuo1, Kouichi Ichimura2. 1. Department of Ophthalmology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, 700-8558, Japan. matsuot@cc.okayama-u.ac.jp. 2. Department of Pathology, Okayama University Graduate School of Medicine, Dentistry, and Pharmaceutical Sciences, Okayama, Japan.