The Values Of Multiple Frequency Tympanometry As Diagnostic Tests Of Middle Ear Function In Infants

Objective To evaluate the values of the multiple frequency probe tones tympanograms and multiple frequency tympanometry in the diagnosis of middle ear function of infants.Methods Using GSI Tympstar middle ear analyzer, tympanometries with 226,678and1000Hz probe tones and multiple frequency tympanometry were performed on infants at age 0～3 year,including normal group(122 infants ,244ears) and abnormal group (141infants,210ears).Results There was no significant differences between above two groups of infants aged 0～6months(P>0.05),but infants elder than 6 mouths(P <0.05). The patterns of 678 Hz and 1000 Hz tympanograms showed significant differences between two groups of infants aged 0～3 year(P <0.05).The resonant frequency expressed no significant differences between two groups of infants aged 0～6 months(P>0.05),but Infants elder than 6 mouths(P<0.05).In normal group, the resonant frequency increases in accordance with age of the infants, it will reach normal range of infants aged 11～36months.Conclusion The tympanometry with three frequency probe tones is sensitive to infants aged 6～36months while tympanometry with 678 Hz and 1 000 Hz probe tones can yield almost accurate diagnostic results in the assessment of the middle ear functions for infants younger than six months. Moreover the resonant frequency will reach normal range of normal infants aged 11～36months , may be helpful to the evaluation of middle ear function of infants aged 6～36months.