Sensorineural hearing loss in the unoperated-on otosclerotic ear.

Severe sensorineural hearing loss occurs in less than 1% of stapedectomized ears. This low percentage remains as an irreducible minimum even among the most experienced and competent surgeons. The etiology has been hypothesized; however, the actual cause remains unknown. The rare occurrence of sensorineural hearing loss of undetermined etiology in the unoperated-on side was reported first in 1967 by Armstrong who presented a series of three patients. No other references have been found since this initial report. Recently three unilateral stapedectomized patients who developed sudden severe sensorineural hearing loss in the unoperated-on ear were studied during the years 1971 through 1979. The hearing loss occurred within 1 week, 6 weeks, and 12 years postoperatively. Although the number is small, a study of this group, in addition to Armstrong's, leads to several interesting considerations: 1. Is the incidence of sudden sensorineural type hearing loss greater, the same as, or less than that which develops in the non-otosclerotic general population? 2. Is there a possibility that the sudden sensorineural hearing loss of undetermined origin would occur at the time of surgery? Would this then be considered as a predisposing if not the actual etiology? The present series of six cases is so small that a conclusion is not possible and inference is only conjecture. It is hoped, however, that this may stimulate past, present, and future search for this unusual occurrence. This may help determine whether or not there is a causal or merely a coincidental relationship.