title: Finite-Element Modelling of the Acoustic Input Admittance of the Newborn Ear Canal and Middle Ear.
abstract: Admittance measurement is a promising tool for evaluating the status of the middle ear in newborns. However, the newborn ear is anatomically very different from the adult one, and the acoustic input admittance is different than in adults. To aid in understanding the differences, a finite-element model of the newborn ear canal and middle ear was developed and its behaviour was studied for frequencies up to 2000 Hz. Material properties were taken from previous measurements and estimates. The simulation results were within the range of clinical admittance measurements made in newborns. Sensitivity analyses of the material properties show that in the canal model, the maximum admittance and the frequency at which that maximum admittance occurs are affected mainly by the stiffness parameter; in the middle-ear model, the damping is as important as the stiffness in influencing the maximum admittance magnitude but its effect on the corresponding frequency is negligible. Scaling up the geometries increases the admittance magnitude and shifts the resonances to lower frequencies. The results suggest that admittance measurements can provide more information about the condition of the middle ear when made at multiple frequencies around its resonance.
authors.affiliation: Department of Biomedical Engineering, McGill University, 3775 rue University, Montréal, QC, H3A 2B4, Canada.
authors.forename: Hamid
authors.initials: H
authors.lastname: Motallebzadeh
authors.affiliation: Department of Biomedical Engineering, McGill University, 3775 rue University, Montréal, QC, H3A 2B4, Canada.
authors.forename: Nima
authors.initials: N
authors.lastname: Maftoon
authors.affiliation: Division of Otolaryngology-Head and Neck Surgery, Montréal Children's Hospital, Montréal, Canada.
authors.forename: Jacob
authors.initials: J
authors.lastname: Pitaro
authors.affiliation: Department of Biomedical Engineering, McGill University, 3775 rue University, Montréal, QC, H3A 2B4, Canada. robert.funnell@mcgill.ca.|Department of Otolaryngology-Head and Neck Surgery, McGill University, Montréal, Canada. robert.funnell@mcgill.ca.
authors.forename: W Robert J
authors.identifier: http://orcid.org/0000-0002-7145-4590
authors.initials: WR
authors.lastname: Funnell
authors.affiliation: Department of Otolaryngology-Head and Neck Surgery, McGill University, Montréal, Canada.|Department of Pediatric Surgery, McGill University, Montréal, Canada.
authors.forename: Sam J
authors.initials: SJ
authors.lastname: Daniel
mesh_terms: D000161:Acoustic Stimulation; D004424:Ear Canal / Q000502:physiology*; D004432:Ear, Middle / Q000502:physiology*; D020342:Finite Element Analysis; D006801:Humans; D007231:Infant, Newborn / Q000502:physiology*; D014732:Vibration
keywords: admittance; clinical measurements; external ear canal; finite-element model; frequency response; infants; linear material properties; middle ear; newborns; sensitivity analysis