Correlation of air-bone gap and size of Enlarged Vestibular Aqueduct in children

Correlation of air-bone gap and size of Enlarged Vestibular Aqueduct in children:



Publication date: May 2020

Source: International Journal of Pediatric Otorhinolaryngology, Volume 132

Author(s): Jenna Van Beck, Sivakumar Chinnadurai, Alison Kemph Morrison, M. Geraldine Zuniga, Bridgett Smith, Christine M. Lohse, Devin McCaslin

Abstract

Objective

Enlarged vestibular aqueduct (EVA) is an inner ear malformation that represents an important cause of pediatric hearing loss. While certain elements in the history or audiogram may suggest EVA, it is most often diagnosed using computed tomography (CT). The present investigation was conducted to determine if the size of the audiometric air-bone gap (ABG) is correlated with the size of the vestibular aqueduct in the pediatric population using three vestibular aqueduct measurements. These included the fundus, midpoint, and porous widths of the vestibular aqueduct.

Study design

This is a retrospective cohort study.

Setting

This study took place at a tertiary care referral center.

Patients

Fifty-five children (33 female; 22 male) with a confirmed diagnosis of unilateral or bilateral EVA as determined by prior imaging of the inner ear were included in the study.

Main outcome measures

Associations of EVA measurements with ABGs at 0.5 and 1 kHz were evaluated using Pearson correlation coefficients.

Results

All of the correlation coefficients were positive, indicating that as EVA measurements increased so did the ABG. Only the correlation between fundus width and ABG at 1 kHz was not statistically significant.

Conclusions

ABGs measured during audiometric testing correlate with the size of the EVA and ABGs can be clinical predictors of the severity of the bony abnormality. These data support the third window theory of conductive hearing loss in pediatric EVA.