Wideband reflectance measurements in newborns: Relationship to otoscopic findings.
OBJECTIVE
Newborn hearing screening includes testing with otoacoustic emissions and the auditory brainstem response. Unfortunately, both tests are affected by the presence of material in the ear canal and middle ear such as vernix, meconium, and amniotic fluid. The objective of this study was to determine to what extent occlusion of the ear canal as seen on otoscopy affects wideband energy reflectance measurements in newborns. A secondary objective was to obtain additional normative wideband reflectance data in newborns.


METHODS
Newborns from a well-baby nursery were enrolled. Wideband energy reflectance measurements and otoscopy were done immediately after the hearing screening. Occlusion of the ear canal as seen on otoscopy was described on a scale of 0-100%.


RESULTS
A total of 156 babies were enrolled (mean age = 25 hours). A statistically significant difference in the reflectance at ambient pressure was found between the 0-70% and 80-100% occlusion groups. There was no significant difference in reflectance between the right and the left ears. The median reflectance pattern generally followed that of previous studies but in certain frequency regions the present reflectance values were higher.


CONCLUSIONS
A significant increase in reflectance occurs when 70%-80% of the ear-canal diameter is occluded. Taking otoscopy findings into account may improve the interpretation of reflectance measurements. However, further studies are required to better establish the relationship between canal occlusion and reflectance.
McGill Auditory Sciences Laboratory, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada; Department of Otolaryngology-Head and Neck Surgery, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada.
Jacob
J
Pitaro
McGill Auditory Sciences Laboratory, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada; Department of Otolaryngology-Head and Neck Surgery, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada.
Laila
L
Al Masaoudi
McGill Auditory Sciences Laboratory, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada; Department of BioMedical Engineering, McGill University, 3775, rue University, Montréal, QC H3A 2B4, Canada.
Hamid
H
Motallebzadeh
McGill Auditory Sciences Laboratory, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada; Department of Otolaryngology-Head and Neck Surgery, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada; Department of BioMedical Engineering, McGill University, 3775, rue University, Montréal, QC H3A 2B4, Canada.
W Robert J
WR
Funnell
McGill Auditory Sciences Laboratory, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada; Department of Otolaryngology-Head and Neck Surgery, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1, Canada; Department of Pediatric Surgery, McGill University, The Montréal Children's Hospital, 1001 Boul. Décarie, Montréal, QC H4A 3J1Canada. Electronic address: sam.daniel@mcgill.ca.
Sam J
SJ
Daniel
D000158:Acoustic Impedance Tests; D004424:Ear Canal / Q000000981:diagnostic imaging*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D005260:Female; D006311:Hearing Disorders / Q000175:diagnosis*; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D015997:Neonatal Screening; D017084:Otoacoustic Emissions, Spontaneous / Q000502:physiology; D038781:Otoscopy
Hearing screening; Newborn; Otoscopic findings; Wideband reflectance