We are delighted to invite you to Lareina Abbott’s M.Sc thesis oral defense.
When: Wednesday, May 9th at 11:00am
Where: Friedman Building, Room 355
Title: Wideband Acoustic Immittance Measures as part of a Newborn Hearing Screening Program in Canadian First Nations and Metis, Caucasian and Other Ethnicity Neonates
M.Sc. Candidate: Lareina Abbott
Supervisory Committee: Dr. Anthony Herdman, Sasha Brown, M.Sc., and Dr. Navid Shahnaz (Research supervisor)
Purpose: There are few data on the prevalence of Otitis Media (OM) in neonates of all ethnicities, especially First Nations and Metis (FNAM) neonates, at birth. There is a need to diagnose the type of hearing loss at the time of Newborn Hearing Screening (NHS) to determine the prevalence and to refer neonates for timely assessment and intervention. Wideband Acoustic Immittance (WAI) is a viable tool that can aid in the diagnosis of conductive hearing loss (CHL) at time of hearing screening.
Design: This cross-sectional study examined the application of WAI measures (Wideband Absorbance (WBA) at Ambient and Tympanometric Peak Pressure (TPP), and Admittance Phase (Yj) as part of a regular NHS protocol. NHS pass/fail rates, likely diagnoses and WAI measurements in FNAM newborns were compared to newborns of other ethnicities. 213 neonates (426 ears) were recruited from the Royal University Hospital in Saskatoon, Saskatchewan. 382 ears met the inclusion criteria: 42 FNAM, 212 Caucasian, 48 Other Ethnicities, and 80 Undeclared Ethnicity.
Results: FNAM neonates had a significantly higher NHS fail rate than neonates of other ethnicities. The WBA of FNAM neonates was significantly lower than that of neonates of other ethnicities in both NHS pass and fail conditions. WBA was significantly lower for neonates who failed the test battery and who failed Transient Evoked Otoacoustic Emission (TEOAE) testing. The difference in WBA at peak pressure was larger than the difference at ambient pressure for neonates who passed or failed a NHS test battery. Yj was significantly lower in neonates who passed the test battery and who had a likely diagnosis of normal hearing.
Conclusions: WBA and Yj are effective in distinguishing ears with likely CHL from normal hearing ears. Pressurized WBA may be more effective than ambient WBA and Yj is a promising measure in the diagnosis of CHL.
FNAM neonates have a higher NHS fail rate and a greater prevalence of likely CHL. WBA of FNAM neonates is lower than that of other ethnicities. Further research is needed to determine if lower WBA in FNAM neonates indicates a greater prevalence of OM or if there is a difference in middle ear anatomy that reduces absorbance of sound compared to neonates of other ethnicities.