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Auditory brainstem response helps diagnose suspected neurologic abnormalities of the 8th cranial nerve, the associated auditory pathways, and the estimation of hearing sensitivity for those unable to accurately provide behavioral hearing evaluation information. It is essential in diagnosing hearing loss, acoustic tumors, and cerebellopontine angle (CPA) tumors. This activity reviews the evaluation of hearing loss in patients who cannot undergo conventional audiometry and highlights the role of the interprofessional team in evaluating and managing this condition. Objectives: Assess the anatomical and physiological pathways involved in ABR wave generation and their clinical implications. Determine the limitations and contraindications of ABR testing, including patient-specific factors such as sedation risks. Select appropriate ABR stimuli types, such as click or tone-burst, based on clinical context and diagnostic goals. Coordinate care for pediatric patients with hearing loss to ensure timely intervention and developmental support. Access free multiple choice questions on this topic.

Auditory brainstem response (ABR), or brainstem auditory Evoked Potentials (BAEP), is an objective measurement of auditory pathway function from the auditory nerve to the mesencephalon. ABR tests synchronous neural function and can estimate hearing sensitivity thresholds in individuals unable to tolerate traditional behavioral audiometry.[1] Electrical activity from the eighth cranial nerve and neurons along the brainstem auditory pathway are recorded by surface electrodes placed on the scalp, forehead, and near the ears for 10 milliseconds after an acoustic stimulus.[2] The readings consist of up to 7 positive wave peaks labeled I-VII with negative troughs in between. It was first introduced into audiology in the 1970s, and its importance has increased with the contemporary guidelines of newborn hearing screening for hearing loss within 3 months of age.[3] It is now essential in diagnosing hearing loss, acoustic tumors, and cerebellopontine angle tumors.[4]

For patients who need general anesthesia or sedation for ABR testing, parents should be educated on the risk of neurotoxicity in the developing brain. Studies have shown that only a few hours of anesthesia exposure can result in neuronal loss in young animals, with adverse effects persisting in later life.[40] Prolonged anesthetic exposure in children has been associated with learning disabilities.[41] The US Food and Drug Administration has issued warnings that general anesthesia and sedation should be minimized for children under 3 years old and limited to 3 cumulative hours.[20]

Patients diagnosed with hearing loss, vestibular schwannoma, or brainstem lesions on ABR should be managed by a multidisciplinary team of otolaryngologists, neurosurgeons, neurologists, audiologists, speech-language pathologists, pediatricians, and primary care physicians. Children with hearing loss should be immediately referred for hearing augmentation with hearing aids, cochlear implants, or speech rehabilitation to promote long-term speech and language outcomes. The pediatrician should monitor Long-term childhood development with regular follow-ups with audiology for routine hearing aid and audiogram assessments. Formal peer support groups for children with hearing loss can aid children and parents in addressing their concerns. The school system should also be involved in providing an optimal learning environment for children with hearing impairments. Patients with vestibular schwannoma or brainstem lesions need a referral to otolaryngology, neurosurgery, and neurology to determine management. If resection of the brainstem lesion is recommended, intraoperative ABR by an audiologist can help preserve auditory function. Long-term monitoring by the primary care physician, neurologist, neurosurgery, and otolaryngologist is recommended if resection is not recommended.