Effects of acute thyroxin depletion on hearing in humans.

Abstract

To study the physiologic effect of acute thyroid hormone depletion on hearing and the function of outer hair cells. Audiologic and otoacoustic emission testing of subjects undergoing total thyroidectomy before surgery and up to 6 weeks after surgery. Magnitude of thyroxin depletion monitored by serum thyroid-stimulating hormone levels. Hearing research laboratory at a state university. Ten patients undergoing total thyroidectomy. Detection of hearing loss on audiogram and decrease or disappearance of otoacoustic emissions as a result of acute thyroxin depletion. No significant changes in the audiogram and otoacoustic emission configurations were detected, although thyroid-stimulating hormone levels became elevated after total thyroidectomy. Although thyroid hormone is thought to play a role in the physiology of hearing in humans, no deleterious effects on hearing can be identified up to 6 weeks after thyroxin depletion.