Sudden Sensorineural Hearing loss are mostly idiopathic in nature but can also occur in identifiable causes such as auto-immune, neoplastic, infective, ototoxicity etc.The results of its debilitating consequences resulting from missed diagnosis and management need to be addressed. In the US only , about 66,000 new cases are reported per year would give an idea of the magnitude of this condition. There is a need to understand the handicap faced by the permanent loss of a sensory organ and hearing loss patients are first evaluated by primary health care providers or at emergency rooms of hospitals rather than an Otolaryngologist.
Timely recognition of the Sudden Sensorineural Hearing loss(SSNHL) by the evaluating physician is the key to the outcomes to the success rate of treatment. A whisper is heard upto 30 db loss and routine conversation upto 60 db , so when a conversation sounds like a whisper a hearing assessment is warranted. SSNHL is diagnosed when hearing loss is more than 30 dB in 3 consecutive hearing frequencies .
History
Sudden Sensori- Neural hearing loss that occurs rapidly within 72 hrs, rules out any obvious causes as it is 90% idiopathic and any symptoms of unilateral fullness or tinnitus or dizziness symptoms may manifest. Need to identify stroke, noise induced deafness, ototoxicity or vestibular schwannoma. Persisting dizziness and tinnitus may indicate a poorer prognosis to the above condition.
Examination
Ear examination is normal, Cranial nerve examination is normal and Tuning fork tests (Rinne and Weber) indicate a Sensori- Neural hearing loss .
Audiometry
Done immediately in a sound treated room with masking to confirm as well as document the type and extent of the hearing loss.
Investigation
Routine blood investigations are enough (lipid profile /sugar a must). MRI with contrast for the IAC protocol is the gold standard to evaluate a Retro- cochlear lesion. In case a scan is contraindicated, one can do an Auditory Brainstem Response (ABR).
Management
Patient education is a must regarding the condition and apprised of its long term implications of the Hearing loss. Systemic steroids are started immediately, prednisolone given as 1mg /kg daily dose for 14 days. Intratympanic steroid injections are the mainstay of treatment given thrice a week or if the hearing improves immediately .
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Case
Male / 61 yr old patient (diabetic) complained of total loss of hearing from the left ear for 3 days for which was using wax dissolving drops . Audiogram showed a profound Sensorineural loss of the left ear and was started on oral steroids. Next day the patient agreed on admission when systemic steroids were given , followed by Intratympanic steroid injection in the left Ear . Within 24 hrs the hearing showed marked improvement and the patient was discharged on oral steroids keeping a constant check on the blood sugars. At the end of 14 days the audiogram was repeated at different centres which showed a complete recovery of the Hearing losses .
In the last month of June 2024 , we had 4 patients of Unilateral Sudden Sensorineural hearing loss and all of them fortunately recovered to the Intratympanic injections of steroids along with the systemic doses given on admission to the hospital . Studies have shown that the role of anti-viral agents , multi- vitamins, vasodilators, and neurotrophic agents are similar to a placebo only .
Of utmost importance is to distinguish between a Sudden Sensori- neural hearing loss and a Conductive hearing loss as it determines the treatment protocols as well as the prognosis . Any delay in diagnosing a Sudden Sensorineural loss can be a disaster for the patient as early intervention ( within a week ) is absolutely mandatory . Patients with SSNHL often present with a complaint of an ear blockage ,so the clinician may feel there is some fluid in the middle ear following a cold or allergy that could mislead the diagnosis . Even if audiological support is not available , a tuning fork provides a very reliable result .
A hum can also be used by the patient in their home surroundings with similar sensitivity and specificity . The patient is asked to hum and if they can hear their own hum louder in the affected ear, then it’s a conductive hearing loss and not an emergency .
Idiopathic Sudden Sensori-Neural Hearing loss is a medical emergency and needs utmost priority management . Hearing tests and MRI scans are the mandatory tests that need to be done. Hospital admission for systemic steroid treatment and Intratympanic (In the Ear ) injections are the gold standards of treatment. So early diagnosis and right treatment protocols are the cornerstones of saving a sensory organ from permanent damage.
(Author: Dr. Divya Prabhat, Jaslok Hospital)
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