Impedance Audiometry and Iatrogenic Hearing Loss

Abstract

Impedance audiometry is a commonly used diagnostic technique for safe, noninvasive assessment of middle ear compliance and acoustic reflexes. We recently identified a case of sensorineural hearing loss as a complication of impedance testing. A case report, review of the world literature, and recommendations are presented. CASE REPORTA 63-year-oldwoman had a 2-year history of gradually progressive hearing loss bilaterally, but worse on the left side. She denied tinnitus, vertigo, and previous otologic problems. There was no history of significant exposure to noise or family history of otologic problems. Her general health was good and physicalexamination of her head and neck was normal. Otomicroscopic examination revealed normal tympanic membranes with good mobility. Tuning fork testing (512 hertz) resulted in a midline Weber test and positive Rinne.Basic audiometry identified a mild sensorineural hearing loss that was flat through the speech frequencies and sloped in the high frequencies (Table 1). There was slight asymmetry of the pure-tone average (27 dB right, 42 dB left) and the speech reception threshold (30 dB right, 35 dB left).