Phase audiometry in neuroaudiological practice

Estrogen and hearing from a clinical point of view; characteristics of auditory function in women with Turner syndrome

Turner syndrome is a chromosomal aberration affecting 1:2000 newborn girls, in which all or part of one X chromosome is absent. This leads to ovarial dysgenesis and little or no endogenous estrogen production. These women have, among many other syndromal features, a high occurrence of ear and hearing problems, and neurocognitive dysfunctions, including reduced visual-spatial abilities; it is assumed that estrogen deficiency is at least partially responsible for these problems. In this, study 30 Turner women aged 40-67, with mild to moderate hearing loss, performed a battery of hearing tests aimed at localizing the lesion causing the sensorineural hearing impairment and assessing central auditory function, primarily sound localization. The results of TEOAE, ABR and speech recognition scores in noise were all indicative of cochlear dysfunction as the cause of the sensorineural impairment. Phase audiometry, a test for sound localization, showed mild disturbances in the Turner women compared to the reference group, suggesting that auditory-spatial dysfunction is another facet of the recognized neurocognitive phenotype in Turner women.

Clinical application of distorted speech audiometry

The clinical validity of four different low-redundant speech tests was calculated using four groups of 83 patients with retrocochlear or central auditory lesions. The speech tests used were: interrupted speech (7 or 10 interruptions/s) time-compressed speech and filtered speech. A comparison between patients and age-matched normal-hearing controls showed that the patients had significantly lower speech recognition score. The best sensitivity ratings of the tests were between 47% and 80%, the highest in patients with cerebellopontine angle tumours and temporal lobe lesions, and the lowest in vascular brainstem lesions. The speech tests with the highest sensitivity were 7 interruptions/s and time-compressed speech.