Asymmetric Sensorineural Hearing Loss Definition and Diagnosis

Audiometric Criteria

The American Academy of Otolaryngology-Head and Neck Surgery defines asymmetric sensorineural hearing loss as a difference in pure tone average of greater than 15 dB between ears at 500, 1000, and 2000 Hz, or a difference in word recognition scores of greater than 15% between ears 1, 2
The American Academy of Otolaryngology-Head and Neck Surgery establishes a pure tone average difference threshold of >15 dB between ears at 500, 1000, and 2000 Hz 1, 2
The American Academy of Otolaryngology-Head and Neck Surgery establishes a word recognition score difference threshold of >15% between ears 1, 2

Asymmetric sensorineural hearing loss warrants immediate investigation for underlying pathology, as age-related hearing loss typically presents as symmetric and gradual bilateral sensorineural hearing loss 1
Symmetric hearing loss is defined as audiometric results within 15 dB for pure tone average between ears with word recognition score differences of 15% or less 1

The American Academy of Otolaryngology-Head and Neck Surgery recommends MRI evaluation to rule out retrocochlear pathology, particularly vestibular schwannoma, in cases of asymmetric sensorineural hearing loss 3, 4
Comprehensive diagnostic workup for asymmetric sensorineural hearing loss includes complete audiometry with pure tone thresholds, speech audiometry, tympanometry, and acoustic reflex testing 4
MRI of the internal auditory canal and posterior fossa is recommended for asymmetric sensorineural hearing loss 3, 4