Effects of acute thyroxin depletion on hearing in humans

Objective: To study the physiologic effect of acute thyroid hormone depleti on on hearing and the function of outer hair cells. Design: Audiologic and otoacoustic emission testing of subjects undergoing total thyroidectomy bef ore surgery and up to 6 weeks after surgery. Magnitude of thyroxin depletio n monitored by serum thyroid-stimulating hormone levels. Setting: Hearing r esearch laboratory at a state university. Subjects: Ten patients undergoing total thyroidectomy. Main Outcome Measures: Detection of hearing loss on a udiogram and decrease or disappearance of otoacoustic emissions as a result of acute thyroxin depletion. Results: No significant changes in the audiog ram and otoacoustic emission configurations were detected, although thyroid -stimulating hormone levels became elevated after total thyroidectomy. Conc lusion: Although thyroid hormone is thought to play a role in the physiolog y of hearing in humans, no deleterious effects on hearing can be identified up to 6 weeks after thyroxin depletion.