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The auditory steady-state response (ASSR) is an electrophysiological testing modality that measures hearing thresholds independent of the behavioral responses required for traditional pure-tone audiometry. In this way, ASSR is similar to auditory brainstem response (ABR) testing. However, unlike ABR, ASSR allows for simultaneous multifrequency testing, shortening the duration of the examination. ABR testing requires the examiner to interpret neural response waveforms, introducing an element of subjectivity but permitting characterization of individual waveform parameters, such as latency. Contrarily, ASSR relies on statistical measures, improving objectivity and reproducibility while limiting latency measurements. ABR and ASSR offer a means to acquire precise hearing thresholds in individuals who cannot or will not cooperate with pure-tone audiometric evaluation. ASSR is particularly valuable in young children who require hearing amplification and whose conventional behavioral audiometry results are unreliable. However, because of its novelty, ASSR has not been widely adopted or standardized, and its results should be interpreted with some degree of caution. This activity describes the indications, contraindications, necessary equipment and personnel, procedural technique, and clinical significance of ASSR testing, particularly in pediatric patients, and highlights the role of the interprofessional team in assessing and treating hearing loss in affected patients. Objectives: Select appropriate patients for an auditory steady-state response examination based on their clinical history. Distinguish auditory steady-state response testing from other auditory evoked potential tests. Compare auditory steady-state response hearing thresholds with other electrophysiological tests and conventional behavioral audiometry. Develop and implement interprofessional healthcare team protocols to facilitate comprehensive hearing evaluations in the pediatric population. Access free multiple choice questions on this topic.

The auditory steady-state response (ASSR) is an objective electrophysiological test to estimate hearing thresholds. ASSR is a newer procedure than other auditory evoked potential (AEP) tests, such as auditory brainstem response (ABR); both ASSR and ABR provide similar hearing threshold results, but ASSR provides more consistent, statistically valid results in less time.[1][2] ASSR was first described by Galambos et al in 1981, highlighting a prominent neural response to 40-Hz tonal stimuli in adults with normal hearing. Initially termed the 40-Hz event-related potential, or steady-state evoked potential, Galambos et al observed its distinctive and consistent presence near the behavioral hearing threshold, suggesting its potential as a predictor of objective hearing threshold.[3] Subsequent studies revealed that the reliable recording of the 40-Hz response was achievable mainly in awake adults. This posed a serious limitation, as this type of objective testing is mostly needed in the pediatric population, often in a sleeping or sedated state. Further work demonstrated that this limitation could be overcome by altering the stimulus parameters.[2][4] Currently, ASSR represents a vital addition to the audiologist's electrophysiological test battery, along with otoacoustic emissions (OAE) and ABR. The ability of the ASSR to test multiple frequencies simultaneously makes it more efficient to perform when infants are asleep. However, it is an emerging technology without widely accepted standardization of testing protocols and equipment, and its results must be interpreted with circumspection.

The complications of ASSR testing are directly due to sedation or general anesthesia and include vomiting, agitation, prolonged sedation, hypoxia, respiratory distress, respiratory obstruction, bradycardia, neurological problems, and apnea. Patient vital signs must be monitored throughout the examination if conducted under anesthesia.[25][19]

The 1-3-6 plan for pediatric hearing loss suggests that hearing loss, if present, should be identified via screening by 1 month of age, a diagnostic evaluation should be completed by 3 months of age, and intervention should be initiated by 6 months of age.[41] This is best achieved by coordination between specialists, particularly pediatricians and otorhinolaryngologists. Children diagnosed with hearing loss should be fitted for hearing amplification immediately, ideally within 1 month after diagnosis. Speech-language pathologists also play a role in rehabilitating patients with hearing-related speech development delays. Further routine follow-up for developmental milestones with pediatricians and audiological evaluation with otorhinolaryngologists are also recommended.