Impaired Hearing Following Instillation of Hydrocortisone into the Middle Ear: Preliminary Report from an Animal Study

Abstract

The effect of cortisone on the inner ear function was investigated. A suspension of 2% hydrocortisone in sterile water was instilled into the middle ear in the round window niche area of healthy rats. The hearing for eight frequencies was determined by auditory brainstem response (ABR) measurements. After 5 days of daily local application, ABR thresholds impaired in the high-frequency range 12 to 31.5 kHz. The impaired ABR thresholds remained unchanged throughout 3 weeks of observation, indicating irreversible damage to the inner ear. It is also noteworthy that hydrocortisone delayed healing of the perforated tympanic membrane.

Key Words:

• cortisone
• topical application
• hearing loss
• auditory brainstem response
• cochlea
• ototoxicity