1. The use of steroids in sudden sensorineural hearing loss is controversial. Most ENT physicians will prescribe 2 weeks of p.o. prednisone. If this does not place the patient at some unusual risk, it certainly provides the maximum opportunity for recovery.
   
   
2. An audiogram is asymmetric (right versus left) if there is greater than 10 dB difference at 2 or more frequencies and if there is a 20% or greater difference in speech discrimination.
   
   
3. Tumor concern is the issue. The greater the asymmetry, the greater the concern. These are generally slow growing tumors, so if the concern is low, retest at 12 months or prn further hearing deterioration. If the concern is greater, retest at 6 months. If there is real asymmetry, the evoked response audiograms are excellent, inexpensive tests.
   
   
4. Hearing aids are most appreciated with greater than 30dB hearing loss with good discrimination. All hearing aids MUST be purchased with a full moneyback 30 day trial period. Only the user knows if he/she derives benefit.
   
   
5. MRI with gadolinium is the best examination for acoustic neuroma and other cerebellar pontine angle (CPA) tumors. Special enhancing coils are typically used, so be sure to indicate suspicion for a CPA tumor.

Overview of Sensorineural Hearing Loss

Most sensorineural hearing loss is symmetric and insidious in onset. Most are a mixture of age (presbycusis) and noise exposure. Some are confounded by the companion tinnitus. Audiology is recommended. For those having communication difficulties, hearing aid evaluation is recommended. Three situations warrant special concern. The first is acute sensorineural hearing loss. The second is asymmetric sensorineural hearing loss and the third is sensorineural hearing loss with abnormalities of discrimination.

Acute sensorineural hearing loss is potentially an autoimmune disease. It is therefore treated with systemic steroids. The recommended dose is 60 mgs orally, daily for 1 week, 40 mgs daily for 1 week and 20 mgs daily for 1 week. If recovery is made, no further evaluation or treatment is required. If recovery is incomplete then the hearing loss is asymmetric and treated as per the ambulatory care pathway. Some believing this is herpetic will treat with high dose antiviral medication.

The issue with asymmetric hearing loss or asymmetric discrimination is that a small percentage of these represent the early symptoms of a cerebellopontine angle tumor. If the asymmetry is greater than 20 decibels or the discrimination percent difference is more than 20%, cerebellopontine angle tumor is a concern. Evoked response audiometry (ABR or BAER) is an excellent, moderately priced test. ABR does not work for hearing losses exceeding 50 dB. For those with abnormal ABR or asymmetry with >50 dB of hearing loss, MRI with gadolinium is recommended.

This then leaves the most common scenario which is asymmetry greater than 10dB but less than 20 or 30dB with reasonable discrimination scores.

In other words, major asymmetry for threshold or discrimination requires ABR and possible MRI to rule out acoustic neuroma.

Minor asymmetry can be followed with repeat audiograms at 6-12 month intervals with ABR and/or MRI if there is further change. Moderate asymmetries require clinical judgement. If concern exists obtain an ABR. If tumor suspicion is low, repeat the audiogram in 6 months and determine the need for workup by increasing hearing loss or asymmetrically deteriorating hearing.

Whether the primary care provider accepts this pathway or chooses a modified or different pathway, some rigorous organized thinking on this topic will benefit the patient, the physician and the practice.