Hearing loss is an uncommon symptom of MS. About 6 percent of people who have MS complain of impaired hearing; hearing loss may take place during an acute exacerbation.
In very rare cases, hearing loss has been reported as the first symptom of the disease.
Deafness due to MS is exceedingly rare, and most acute episodes of hearing deficit caused by MS tend to improve.
Hearing loss is usually associated with other symptoms that suggest damage to the brainstem — the part of the nervous system that contains the nerves that help to control vision, hearing, balance and equilibrium.
Hearing deficits caused by MS are thought to be due to inflammation and/or scarring around the eighth cranial nerve (the auditory nerve) as it enters the brainstem, although plaques (abnormal areas that develop on nerves whose myelin has been destroyed) at other sites along the auditory pathways could also contribute to hearing problems.
Because hearing deficits are so uncommon in MS, people with MS who do develop hearing loss should have their hearing thoroughly evaluated to rule out other causes.