Fluoride therapy for cochlear otosclerosis? an audiometric and computerized tomography evaluation.

The progress of sensorineural hearing loss (SNHL) in patients with cochlear otosclerosis was compared for 19 patients treated with fluoride for 1-5 years and 22 untreated controls. CT scans of eight patients before and after fluoride treatment were evaluated visually. Fluoride therapy arrested the progression of SNHL in the low (250, 500 and 1,000 Hz) (p < 0.001) and high (2 and 4 kHz) (p = 0.008) frequencies. It seemed to be more effective for the higher frequencies in cases with an initial SNHL of < 50 dB. Fluoride administration for 4 years did not seem to be superior to a shorter treatment period (1-2 years). For six patients followed up after discontinuing fluoride therapy there was minimal deterioration in SNHL. There was no clear relationship between the size and site of otospongiotic lesions on CT and the severity of SNHL. Follow-up with CT evaluation did not provide reliable information as to the efficacy of fluoride therapy.