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Background Audiologists often lack confidence in results produced by current protocols for diagnostic electrophysiologic testing of infants. This leads to repeat testing appointments and slow protocols which extend the time needed to complete the testing and consequently delay fitting ofamplification.Arecent publication (Sininger et al50) has shown how new technologies can be applied to electrophysiologic testing systems to improve confidence in results and allow faster test protocols. Average test times for complete audiogram predictions when using new technologies and protocols were found to be just over 32 minutes using auditory brainstem response (ABR) and just under 20 minutes using auditory steady-state response (ASSR) technology. Purpose The purpose of this manuscript is to provide details of expedited test protocols for infant and toddler diagnostic electrophysiologic testing. Summary Several new technologies and their role in test speed and confidence are described including CE-Chirp stimuli, automated detection of ABRs using a technique called FMP, Bayesian weighting which is an alternative to standard artifact rejection and Next-Generation ASSR with improved response detection and chirp stimuli. The test protocol has the following features: (1) preliminary testing includes impedance measures and otoacoustic emissions, (2) starting test levels are based on Broad- Band CE-Chirp thresholds in each ear, (3) ABRs or ASSRs are considered present based on automated detection rather than on replication of responses, (4) number of test levels is minimized, (5) ASSR generally evaluates four frequencies in each ear simultaneously with flexibility to change all test levels independently. Conclusions Combining new technologies with common-sense strategies has been shown to substantially reduce test times for predicting audiometric thresholds in infants and toddlers (Sininger et al50). Details and rationales for changing test strategies and protocols are given and case examples are used to illustrate. [ABSTRACT FROM AUTHOR]

Background: The video head impulse test (vHIT) is a new tool being used in vestibular clinics to assess the function of all six semicircular canals (SCCs) by measuring the gain of the vestibulo-ocular reflex (VOR) in response to rapid head turns. Whereas vHIT has been validated in adults for all SCCs, there are few studies describing the normal response in children, particularly for stimulation of the vertical canals. Purpose: The purpose of this study was to characterize the normal vHIT response for all six SCCs in children aged 4-12 years. Research Design: A cross-sectional prospective descriptive study. Study Sample: Forty-one participants were categorized into one of four groups based on their age (4-6 years, 7-9 years, 10-12 years, and adults) with at least ten participants in each age group. Data Collection and Analysis: The ICS Impulse system (GN Otometrics, Schaumburg, IL) was used to perform vHIT on each participant. Lateral, anterior, and posterior SCCs were stimulated by thrusting the head in the plane of the canal being evaluated and resulting VOR gain measures were calculated as eye velocity divided by head velocity. VOR gain of the pediatric age groups was compared with adults for all SCCs. Results: There were no significant differences in mean VOR gain between the three pediatric age groups for any SCC measured; thus, the pediatric data were combined into one group of 30 children for comparison with the adult group. Results showed that the pediatric group had significantly higher mean VOR gain than the adult group during left lateral SCC testing. A significantly lower mean VOR gain, however, was observed for the children compared with the adult participants for left anterior and right posterior (LARP) impulses. There was a large amount of variability in the data during right anterior and left posterior (RALP) impulse testing for both the pediatric and the adult groups, which was at least partially attributed to large pupil diameter in the younger participants. Test time decreased with an increase in age for all impulse conditions (lateral, RALP, and LARP). Several modifications were necessary to obtain adequate data on the pediatric participants. Conclusions: vHIT can be used to successfully measure the function of the lateral SCC in children as young as 4 years of age. Our results provide normative gain values that can be used when testing children with lateral vHIT. Care must be taken to obtain the most accurate measures and reduce variability when testing children, particularly with LARP and RALP. Our data would suggest that lower gain cutoffs should be used for LARP and RALP testing in children than the cutoffs used for lateral vHIT. Further research is warranted to study LARP and RALP response reliability and validity in children because of the highly variable VOR gains found in this population. Pediatric modifications for successfully administering vHIT and obtaining reliable results are discussed. [ABSTRACT FROM AUTHOR]