“…In the other case, an abrupt deterioration of loudness perception required an increase in electrical stimulation. Generally, new bone formation is seen in the cochlea after cochlear implantation for deafness of various etiologies [Li et al, 2007; Somdas et al, 2007; Seyyedi and Nadol, 2014; Kamakura and Nadol, 2016], as well as in the cochleae deafened by Cogan’s syndrome without cochlear implantation [Fisher and Hellstrom, 1961; Wolff et al, 1965; Zechner, 1980; Rarey et al, 1986; Schuknecht and Nadol, 1994]. Postoperative word recognition scores have been reported to be negatively correlated with the % volume of new bone formation within the cochlea after implantation [Kamakura and Nadol, 2016].…”