1. Division of Ophthalmology, Iwamizawa Municipal Hospital, Iwamizawa, Japan.
2. Department of Anatomy and Embryology II, Faculty of Medicine, Complutense University, Madrid, Spain.
3. Department of Anatomy, Akita University School of Medicine, Akita, Japan.
4. Division of Internal Medicine, Iwamizawa Kojin-kai Hospital, Iwamizawa, Japan.
5. Department of Anatomy, Sapporo Medical University, Sapporo, Japan.
6. Department of Ophthalmology, Sapporo Medical University, Sapporo, Japan.