In Response to Letter to the Editor

Abstract

To the Editor Thank you for your letter and comments. We agree there may be multiple mechanisms of sensorineural hearing loss in otosclerosis, some of which do not require a focus of otosclerosis to abut the cochlear endosteal layer. The interest in identifying whether a focus of otosclerosis involves the cochlear endosteum comes from multiple previous studies correlating elevated bone thresholds to hyalin deposition in the spiral ligament (1–3). This hyalinization occurs adjacent to otosclerotic foci in the cochlear bone and has also been associated with atrophy of the adjacent stria vascularis. Immunostaining of human temporal bones with hyaline deposition in the spiral ligament has demonstrated decreased Na+, K+ ATPase in the adjacent stria vascularis, which may play a role in the associated sensorineural hearing loss seen in these patients (4). It is doubtful that any of the 3 cases of false-positive otosclerosis on CT represented end-stage histologic otic capsule otosclerosis. The clinical and audiologic histories of these 3 patients were not consistent with pure cochlear otosclerosis. One patient had a vestibular schwannoma with progressive profound sensorineural hearing loss. The second patient had normal hearing, with the exception of mild high-frequency sensorineural hearing loss appropriate for age. This temporal bone was acquired because the patient’s contralateral ear had Ménière’s disease. The third temporal bone came from a patient with chronic otitis media. She had a mixed hearing loss that could be explained by the history and histopathologic findings consistent with chronic otitis media. We reexamined these specimens and found no evidence of other foci of otosclerosis throughout the otic capsule or in the adjacent area. Alicia Marie Quesnel M.D. Department of Otolaryngology Massachusetts Eye and Ear Infirmary Boston, Massachusetts, U.S.A. Department of Otology and Laryngology Harvard Medical School Boston, Massachusetts, U.S.A. Gul Moonis M.D. Department of Radiology Massachusetts Eye and Ear Infirmary Harvard Medical School Boston, Massachusetts, U.S.A. Department of Radiology Beth Israel Deaconess Medical Center Boston, Massachusetts, U.S.A. Jason Appel M.D. Department of Radiology Massachusetts Eye and Ear Infirmary Harvard Medical School Boston, Massachusetts, U.S.A. Jennifer T. O’Malley B.A. Department of Otolaryngology Massachusetts Eye and Ear Infirmary Boston, Massachusetts, U.S.A. Department of Otology and Laryngology Harvard Medical School Boston, Massachusetts, U.S.A. Hugh D. Curtin M.D. Department of Radiology Massachusetts Eye and Ear Infirmary Harvard Medical School Boston, Massachusetts, U.S.A. Michael J. McKenna M.D. Department of Otolaryngology Massachusetts Eye and Ear Infirmary Boston, Massachusetts, U.S.A. Department of Otology and Laryngology Harvard Medical School Boston, Massachusetts, U.S.A. The authors disclose no conflicts of interest.