Training in ABR
ASSR vs ABR in children with normal hearing and hearing loss
Description
Summary of: Sininger, Yvonne S.; Hunter, Lisa L.; Hayes, Deborah; Roush, Patricia A.; Uhler, Kristin M. Evaluation of Speed and Accuracy of Next-Generation Auditory Steady State Response and Auditory Brainstem Response Audiometry in Children With Normal Hearing and Hearing Loss. Ear and Hearing 39(6):p 1207-1223, November/December 2018. | DOI: 10.1097/AUD.0000000000000580
This detailed research article describes the study of electrophysiological hearing thresholds using the Interacoustics Eclipse EP system in 102 infants and toddlers (58F 44M), where 59% were 5 months or younger at the time of assessment. Sininger states the objectives of the study was to compare the predicted audiometric thresholds obtained by ASSR and ABR in this sample when both techniques use optimal stimuli and detection algorithms. The stated aim was to address the past discrepancies studies found between ABR and first generation ASSR measures. The second objective of Sininger’s team was to determine and compare test times required by the 2 techniques to predict thresholds for both ears at the 4 audiometric frequencies of 0.5, 1.0, 2.0, and 4.0 KHz. The data for determined thresholds within the study was evaluated by Sininger and correction factors applied. The findings of the study demonstrated thresholds were significantly lower for ASSR than ABR, and showed greatest difference at 0.5 and1.0KHz, with up to 14 dBnHL lower thresholds being detected using ‘next generation’ detection when compared to ABR using an automated response detection (FMP). The improvement in ASSR threshold detection was attributed to the advances implemented in the Eclipse EP system for response detection utilising information at multiple harmonics of the modulation frequency. The stimulation paradigm which utilised NB CE-Chirp also contributed to the lower absolute levels in nHL. The research clinicians in this study obtained all 8 thresholds in one appointment in 83% of ABR, and 87% ASSR assessments. Within the study participants 49% had thresholds determined as normal by ASSR and ABR. The time to obtain 8 frequency specific thresholds for these infants was 24.02 mins for ABR, and 15.31 mins for ASSR. The features of the Eclipse EP system that the authors call ‘next generation’ detection when compared to the first generation ASSR measures, are summarised as the assessment of 12 harmonics, rather than 1, and the use of both phase and amplitude information, rather than one or the other, as well as careful calculation of appropriate test criterion. This study demonstrates that ASSR using the Eclipse is now a suitable alternative as well as a quicker test to perform than ABR in measuring hearing threshold in infants.
