The Mizuo–Nakamura Phenomenon is a phenomenon observed in Oguchi's disease. It was named after Gentaro Mizuo (1876–1913) and Bunpei Nakamura (1886–1969), Japanese ophthalmologists. The Mizuo–Nakamura Phenomenon is a phenomenon observed in Oguchi's disease. It was named after Gentaro Mizuo (1876–1913) and Bunpei Nakamura (1886–1969), Japanese ophthalmologists.