Study Of Resonant Frequency In Diagnosing Of Low Conductive Hearing Loss

Objective To investigate the relationship between the resonant frequency and low frequency conductive hearing loss. Study whether we can deduce low conductive hearing loss from the change of resonant frequency. Discuss whether the resonant frequency can be used to estimate the children' hearing loss when they can not cooperate in pure tone audiometry and deduce whether the pure tone audiometry is reliable or not for children and psyperhydocusis. Method Cross sectional study is applied to compare the resonance frequencies in normal hearing group with that in low frequency conductive hearing loss group. One hundred and six ears were included. Pure tone audiometry is considered gold standard. Fifty-three ears are divided into low frequency conductive hearing loss group and fifty-three ears are divided into normal hearing group(≤15dBHL, air-bone gap≤10dB ).Receiver operator characteristic (ROC) curve was used to discuss whether the resonant frequency was powerful in diagnosing low conductive hearing loss and find the most appropriate cutoff point for diagnosing low frequency conductive hearing loss and Levene's test was used to test the difference of the lowfrequency conductive hearing loss and normal hearing groups. P^0.05 is considered statistics difference. Use SPSS 11.5 to do statistic analyze. Results The resonant frequency of low frequency conductive hearing loss and normal hearing group were different. The optimum cutoff points of resonant frequency were 850Hz and 1050 Hz. The resonant frequency range from 850Hz to 1050Hz was considered normal. The test was powerful when the resonant frequency was lower than 850Hz. The test was powerless when the resonant frequency was higher than 1050Hz.Conclusion Conductive hearing loss could be predicted from resonant frequency when it is lower than 850Hz. The children who can not cooperate in pure tone audiometry can be predicted conductive hearing loss when the resonant frequency is lower than 850Hz. But can not deduce low conductive hearing loss from the resonant frequency. The reliability and authenticity of children and psyperhydocusis can be predicted from the resonant frequency in some degree. The test was powerless when the resonant frequency was higher than 1050Hz. ENT (ear, nose and throat) doctors and audiologists have to be careful about how to explain the results when the resonant frequency is higher than 1050Hz.