Audiological investigations in patients with late onset facioscapulohumeral muscular dystrophy (FSHD)Fei Zhao1, Dafydd Stephens2, Mark Rogers3 and Peter Harper3
We have systematically tested the peripheral auditory system in 21 late-onset FSHD cases. The pure tone thresholds did not differ significantly at low and mid frequencies in either better ear or worse ear between FSHD subjects and controls. The patients with FSHD had significantly better hearing thresholds at 4 and 6kHz than the normative data in the better and the worse ears. Transient evoked otoacoustic emissions (TEOAEs) were recorded as an objective and sensitive method for evaluating cochlear function. A significantly lower occurrence of TEOAEs was found in the FSHD patients with hearing thresholds better than 20dB HL. Furthermore, this study provides evidence for the neuromuscular abnormalities of FSHD through its findings on the relaxation time of the acoustic stapedial reflex. A significantly longer relaxation time was found in patients with FSHD. No significant correlations were found between age and severity, or between duration and severity. Moreover, there were no significant correlations between hearing level and clinical severity in patients with FSHD.