title: Letter to the Editor: The bispectral index is a dimensionless number.
authors.affiliation: Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Kotoe
authors.initials: K
authors.lastname: Kamata
authors.affiliation: Surgical Center, Osaka Prefectural Osaka General Medical Center, Osaka, Japan.
authors.forename: Satoshi
authors.initials: S
authors.lastname: Hagihira
authors.affiliation: Neurological Institute, Tokyo Women's Medical University, Tokyo, Japan; and.|Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Maruyama
authors.affiliation: Neurological Institute, Tokyo Women's Medical University, Tokyo, Japan; and.|Faculty of Advanced Techno-Surgery, Institute of Advanced Biomedical Engineering and Science, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Muragaki
authors.affiliation: Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Makoto
authors.initials: M
authors.lastname: Ozaki
mesh_terms: D000758:Anesthesia; D003399:Craniotomy; D019054:Evoked Potentials, Motor; D016343:Monitoring, Intraoperative; D014851:Wakefulness