Wideband absorbance measures in neonates and young infants

Abstract

Evaluation of middle ear status in young infants is a challenge in both screening and diagnostic contexts due to a lack of valid and objective tools of middle ear assessment . The standard tools used to determine the middle ear status in older children are neither efficient nor accurate in evaluating young infants.Wideband absorbance (WBA) is recommended as a tool for middle ear assessment in young infants due to its time efficiency, reliability, objectivity and ability WBA. The neonates were tested prior to their discharge from the hospital. In addition, a total of 36, 30, 33 and 30 infants were seen at 1, 2, 4, and 6 months of age, respectively. These infants were tested using HFT, DPOAE and WBA.The results revealed that conductive hearing loss was common among infants referred through NHS. Australian Aboriginal infants had significantly higher rates of middle ear pathology and conductive hearing loss at birth and showed poor resolution of middle ear pathology over time compared to non-Aboriginal infants. Use of a test of middle ear function (eg. WBA) as an adjunct to the screening tool to facilitate management and prioritisation of infants for further testing was recommended (Chapter Two). Normative ambient pressure WBA data were established for 66 neonates who passed a test battery of AABR, HFT, ASR, TEOAE and DPOAE tests. There was a significant difference in WBA across frequencies from 250 to 8000 Hz (Chapter Three). Test performance of WBA was compared across four single tests and five test battery reference standards in 192 neonates. The test performance of WBA against the test battery reference standards was better than that against single test reference standards (Chapter Four). Despite equal pass rates as determined by a test battery of HFT and DPOAE, the WBA of Aboriginal neonates who passed the test battery was significantly lower suggesting that Aboriginal neonates had more significant outer/middle ear conditions than Caucasian neonates. WBA appeared to be more sensitive to middle ear status than test battery comprising HFT and DPOAE (Chapter Five). In a cross sectional study of infants, developmental effects were evident during the first six months of life, with WBA reducing with age. Although data from the study could be used as reference standard for detecting middle ear disorders, further development of age-specific normative WBA was recommended (Chapter Six).