Objective: To describe a case of contralateral hearing loss (CHL) in vestibular schwannoma (VS) surgery and to discuss the factors potentially related with this complication.
Clinical presentation: A 48-year-old man awakened with complete bilateral hearing loss after an uneventful retrosigmoid excision of a 20 mm left-sided VS. The patient had no complaints of vertigo or facial palsy on the contralateral side. The hearing loss proved to be endocochlear in origin and no improvement was observed after a 24-month follow-up period.
Discussion: CHL in VS surgery is not commonly reported but can occur frequently as a subclinical phenomenon if it is specially addressed. The cause is a compensatory endolymphatic hydrops generated by the loss of cerebrospinal fluid. In this circumstance, the hearing loss is usually reversible within 3 months, but irreversible cases have been described. Vascular damage to the cochlea can be another explanation in irreversible cases. The significance of other potential factors described in the literature as a cause of CHL in VS surgery is less clear.
Conclusion: A case of CHL after VS surgery is presented. The hearing loss proved to be endochlear in origin and irreversible in nature. Irreversible damage to the cochlea resulting from loss of cerebrospinal fluid or vascular injury is probably related in this case reported.