Comparison of One-Year auditory rehabilitation outcomes by etiology in pediatric patients with bilateral severe hearing loss (70-90 dB): enlarged vestibular aqueduct vs. Other causes.

Abstract

Purpose: This study aimed to compare short-term language outcomes following hearing aid rehabilitation in pediatric patients with severe bilateral hearing loss (70-90 dB), with a particular focus on differences according to etiology. We hypothesized that children with enlarged vestibular aqueduct (EVA) exhibit more favorable speech development compared to those with other genetic or structural causes of hearing loss, and explored the potential presence of a "hidden" air-bone gap associated with EVA.

Methods: We retrospectively reviewed 36 children under five years of age diagnosed with bilateral severe sensorineural hearing loss and ascertained before age two at Seoul National University Bundang Hospital. Patients were classified into EVA (n = 16) and non-EVA (n = 20) groups based on radiologic and genetic data. All participants underwent one year of bilateral hearing aid rehabilitation. Speech and language outcomes were assessed using the Categories of Auditory Perception (CAP), Sequenced Language Scale for Infants (SELSI), and Receptive and Expressive Vocabulary Test (REVT), and were compared pre- and post-treatment.

Results: Both groups showed improved CAP scores after one year. However, the EVA group exhibited significantly better expressive language percentile scores (mean 41.8 ± 30.9) compared to the non-EVA group, despite progressive threshold deterioration. Receptive language also improved more in the EVA group, although not statistically significant.

Conclusion: Children with EVA may achieve superior short-term language outcomes with hearing aids, potentially due to a third window-related hidden air-bone gap. However, given the progressive nature of EVA, long-term follow-up is required to assess articulation development and determine optimal timing for cochlear implantation.