This is an unusual but serious form of hearing loss. In this condition, patients will suddenly lose some to all of their sensorineural (or nerve) hearing. It almost always affects a single ear. The cause is unknown but may be related to a viral infection in the inner ear, or from a lack of blood supply to the inner ear. A common scenario is a patient that is suffering from the common cold and has some associated ear stuffiness. However, as the cold symptoms subside, they realize one ear is still hearing poorly. Sometimes a patient will otherwise feel fine but wake up one day with poor hearing from an ear. Alternatively, the episode may occur in the midst of normal daily activities when the hearing will suddenly drop in one ear. Often times, this is also accompanied by loud ringing in the ear or a sensation of fullness or “cotton in the ear”. Patients with diabetes seem to be more susceptible to sudden sensorineural loss, likely due the small blood vessel changes that accompany the disease.
It can be difficult for patients and primary care doctors to know if the hearing loss is related to a nerve injury, or simply from having fluid in the middle ear as can often happen with the common cold. The first step is to look into the ear with an otoscope to see if there are signs of inflammation or fluid. A tuning fork is very helpful if available. The vibrating tuning fork should be placed on one of the central upper teeth. If there is fluid in the ear, the tuning fork will actually be heard more loudly in the ear that is having difficulty. However, if the tuning fork is heard more loudly in the “good” (unaffected) ear, this suggests a nerve hearing loss.
Sudden sensorineural loss is a condition that the ENT doctor should see as quickly as possible. The initial evaluation typically involves an ear exam as well as a hearing test to confirm the diagnosis. If there is a sudden sensorineural loss, steroid treatment is offered. This can be done by oral tablets and/or by injecting steroid solution into the middle ear space. The ENT doctor will be able to review these options along with the risks and benefits of each. Data shows that this therapy is most successful if given early after the hearing loss onset, within the first days if possible, or at least within the first couple of weeks.