1. Departments of Neurosurgery and
2. Ophthalmology, Kitasato University School of Medicine, Sagamihara, Kanagawa, Japan
3. Department of Clinical Laboratory, Kitasato University Hospital, Sagamihara, Kanagawa, Japan; and
4. Department of Neurology, St. Marianna University School of Medicine, Kawasaki, Kanagawa, Japan