Initial screening test for newborn hearing disorder is
OAEs are used as a screening test of hearing in neonates and to test hearing in uncooperative or mentally challenged individuals after sedation. Other uses of OAE: They help to distinguish cochlear from retrocochlear hearing loss. OAEs are absent in cochlear lesions, e.g. ototoxic sensorineural hearing loss. They detect ototoxic effects earlier than pure tone audiometry. OAEs are also useful to diagnose retrocochlear pathology, especially auditory neuropathy. Auditory neuropathy is a neurologic disorder of CN VIII. Audiometric tests, e.g. SNHL for pure tones, impaired speech discrimination score, absent or abnormal auditory brainstem response, show a retrocochlear type of lesion but OAEs are normal. Note: OAEs are absent in 50% of normal individuals Lesions of the cochlea Middle ear disorders (as sound travelling in the reverse direction cannot be picked up) and When hearing loss exceeds 30 dB Ref: Dhingra; 6th Edition; pg no 28
ABR - Auditory Brainstem Response
Otoacoustic Emissions
Free Field Audiometry
Visual reinforcement audiometry
Ear