Electronystagmographic puzzle: What's your interpretation? (Vestibulology Clinic).

A 46-year-old man came to the office with a lifelong awareness of hearing loss in the left ear. Two months earlier, he experienced a further stepwise decline in his hearing in the left ear following an upper respiratory infection. In addition, aural fullness had been present in his left ear for 9 months. The Onset of the aural fullness was accompanied by an intermittent tinnitus on the left that had become constant 3 weeks earlier. The patient had no history of dizziness.

The results of a tuning-fork test suggested a sensorineural hearing loss on the left. While performing the sharpened tandem Romberg test, the patient had more difficulty with the left foot forward. Audiology revealed a mild to moderate, mixed, and primarily conductive hearing loss in the left ear. His speech reception threshold was 30 dB and his speech discrimination score was 100% at 70 dB. Findings on tympanometry were normal, but his acoustic stapedial reflexes were absent in the ipsilateral left ear. Ultra-thin computed tomography of the temporal bones (pixel size: 0.07 mm) detected a sclerotic plaque in the basal turn of the cochlea of the right ear, a sclerotic plaque in the oval window of the left ear, pericochlear lucency in both ears (moreso on the left), and a mild thickening of the footplate in the left ear. The internal auditory canals were symmetrical.

How would you interpret this electronystagmographic study?

Your comments would be appreciated. Please send your remarks to Kenneth H. Brookler, MD: [e-mail]

From Neurotologic Associates, P.C., New York City.