1. Department of Rehabilitation Medicine, The Jikei University School of Medicine, 3-25-8 Nishi-Shimbashi, Minato-Ku, Tokyo 105-8461, Japan
2. Department of Rehabilitation Medicine, Shimizu Hospital, 129 Miyagawacho, Kurayoshi, Tottori 682-0881, Japan
3. Department of Radiological Sciences, Graduate School of Human Health Sciences, Tokyo Metropolitan University, 7-2-10 Higashi-Ogu, Arakawa-ku, Tokyo 116-8551, Japan