Audiological and radiological profile of bilateral large vestibular aqueduct syndrome with Mondini dysplasia in a pediatric patient: A case report

Introduction: Bilateral Large Vestibular Aqueduct Syndrome (LVAS) is a congenital inner ear malformation frequently associated with Mondini cochlear dysplasia and is a well recognized cause of fluctuating sensorineural hearing loss in children. Early identification through radiological and audiological correlation is essential to guide timely rehabilitative decisions, including hearing aid fitting and cochlear implant candidacy. Case presentation: A 6-year old female presented with bilateral hearing impairment and a history of hearing deterioration in the left ear over approximately six months. Previous audiometry documented profound hearing loss in both ears. The child had received intravenous steroid treatment for left sided sensorineural hearing loss, with only temporary improvement reported. A history of third-degree parental consanguinity was documented. MRI and high-resolution CT of the petrous temporal regions demonstrated bilateral enlarged vestibular aqueducts measuring 2.3 mm on the right and 2.0 mm on the left, with hypoplasia of the apical and middle portions of the cochlea, described radiologically as Mondini malformation. Pure tone audiometry performed on 23 June 2026 indicated severe mixed hearing loss bilaterally. Tympanometry revealed type A tympanogram in both ears, while distortion-product otoacoustic emissions were absent bilaterally. Auditory brainstem response testing indicated moderately severe hearing loss bilaterally, with wave V responses obtained till 80dBnHL. A bilateral hearing-aid trial using Oticon Zircon 2 RIC devices demonstrated aided responses within the speech spectrum except at 4kHz, with an aided sound-field average of approximately 25 dBHL and a speech discrimination score of 80%. The audiological recommendations included hearing-aid fine-tuning, frequency transposition, periodic hearing evaluation, auditory training, and ENT review. The ENT team documented bilateral cochlear implantation, followed by audio-verbal therapy, as the management plan Conclusion: This case highlights the importance of correlating audiological and radiological findings in a child with progressive bilateral hearing loss, and underscores the role of comprehensive serial Audiological monitoring in guiding the transition from hearing aids to cochlear implantation in children with LVAS and Mondini malformation.