Abstract:

To explore characteristics of auditory steadystate response (ASSR) and auditory brainstem response (ABR) in patients with large vestibular aqueduct syndrome (LVAS). MethodsCharacteristics of ASSR and ABR of 63 patients (121ears) with LVAS and 20 patients (40ears) of SHL without LVAS were recorded and analyzed. ResultsIn the LVAS group, ASSR raised in a nearly straightline from 0.5 to 4?kHz thresholds until the threshold of response 4?kHz, with an increase of lowfrequency hearing threshold, the value of the slope was reduced. When the biggest boost in frequency was given, response threshold at 1kHz finally disappeared. When stimulated by the maximal sound of ABR, 84 ears could not draw forth the V wave, whose corresponding ASSR could draw forth the response threshold in all or part frequencies. In the other group, ASSR from 0.5 to 4?kHz thresholds rose mostly in a flat type. The average value of ASSR from 2 to 4?kHz thresholds was similar to that of wave Ⅴ of ABR. ConclusionsASSR of LVAS from 0.5 to 4?kHz thresholds rose in a nearly straightline relationship until the thresholdof response disappeared. The correlation was obvious with an increase of frequency. ASSR and ABR thresholds were significantly correlated and the ASSR thresholds had a stage change with the change interval between 80 and 100?dBHL.

Key words:  Large vestibular aqueduct syndrome; Multiple auditory steadystate evoked response (ASSR); Auditory brainstem response (ABR); Infants