Rise or fall and plateau time optimization for cervical vestibular-evoked myogenic potential elicited by short tone bursts of 500 Hz

Abstract

Objective: Literature on clinical utility of cervical vestibular-evoked myogenic potential (cVEMP) has been increasing rapidly, though not without inconsistencies in spite of involving similar populations. Close examination of methods across studies exposed the use of variable stimulus parameters, especially rise/fall time (R/FT) and plateau time (PT) as the possible reason. However the effect of variation in R/FT and PT on cVEMP response parameters has been largely uncharted. Design: The study aimed at evaluating the impact of R/FT and PT on cVEMPs elicited by 500-Hz short tone-bursts (STBs) at 95 dB nHL using R/FT from 1 to 4 ms and PT from 0 to 3 ms. Study sample: 30 healthy individuals with normal audio-vestibular system. Results: Significant prolongation of latencies with increasing R/FT and PT (p < 0.05) was noticed. The amplitude however varied significantly only for some R/FTs and PTs. R/FT of 2 ms, in combination with 1-ms PT, produced large amplitudes with lowest variability in amplitude and latency parameters. Conclusions: R/FT of 2 ms along with PT of 1 ms formed a good amalgamation and could be considered optimum for clinical recording of cVEMPs elicited by 500-Hz STBs, although slight deviances in these parameters might not impact the outcome significantly.