Sudden Sensorineural Hearing Loss
This month’s blog will cover Sudden Sensorineural Hearing Loss (SSNHL), which is defined as sensorineural hearing loss of at least 30 dB in 3 sequential frequencies that occurs over 3 days or less. The incidence of SSNHL is 5-30 cases per 100,000 per year. Tinnitus is an associated symptom approximately 80% of the time.
Hearing loss can cause significant limitations on activities of daily living and communication. Any significant hearing loss should be evaluated by a physician. Your primary care physician can evaluate for cerumen, otitis media, and middle ear fluid. If no clear cause of the hearing loss is identified, prompt referral to an otolaryngologist is the next step in the evaluation to confirm or exclude a diagnosis of SSNHL. A thorough history and neuro-otologic exam is then performed. In SSNHL, typically the outer ear and middle ear exam are normal and the diagnosis is confirmed with comprehensive audiogram.
The list of possible causes of SSNHL is fairly long and broad. The more common etiologies that can cause SSNHL include viral/infectious (eg. Mumps, varicella, HIV, etc.), vascular (blood flow problems to the inner ear), immune-mediated, neurological, and medication related etiologies. Typically, it is difficult to determine the exact cause in most patients.
Prognosis for hearing recovery is generally good but can be highly variably and some patients do not recover any hearing no matter the treatment.
Treatment recommendations are made depending on the underlying cause of the SSNHL. Studies have shown that the chances for hearing improvement increase when treatment is given within 2 weeks of the onset of the hearing loss. In the absence of a definitive cause, oral prednisone (10-14 days) is the most common recommended treatment. Intratympanic steroid injections can also be considered, particularly when oral steroids are contraindicated (eg. some diabetics). Antiviral medications have been utilized in certain circumstances, but are generally not helpful. Patients then require close follow up exams and audiometric testing to measure their improvement. Audiometric rehabilitation is considered when the hearing stabilizes. Other symptoms such as tinnitus or vertigo may require special attention and treatment.
In summary, Sudden Sensorineural Hearing Loss, though not common, can cause significant morbidity and impact on one’s lifestyle. Prompt diagnosis and treatment can increase the chances for a full recovery. The physicians and audiologists at Raleigh ENT are available to help patients who may have SSNHL or related concerns.