Conductive hearing loss is a common clinical condition caused by disorders of the middle and external ear. Here, we report a case of conductive hearing loss with complete tympanic membranes. Clinical examinations revealed no external and middle ear lesions, but high-resolution temporal bone computed tomography revealed enlarged vestibular aqueducts. Detailed audiological tests and follow-up results indicate that the exclusive air-bone gap is the outcome of inner ear malformation but not middle ear lesions, preventing the need for tympanic assessment.
Keywords: conductive hearing loss; enlarged vestibular aqueduct; otosclerosis; third window lesions.