A New Method for Vestibulo-Collic Reflex

ABSTRACT

OBJECTIVE: Vestibulo-collic reflex (VCR) has been thought to be a simple and reliable test in evaluating the vestibular function. But it can only be examined by actively contracting the sternocleidomastoid muscle (SCM) and it would be impossible to conduct the examination without the cooperation of the subject. The aim of this study was to demonstrate a new method for VCR in the absence of the subject's cooperation. METHOD: Records were collected from 20 volunteers. Each subject was properly positioned on the bed with the head flexed, ipsilaterally bent and contralaterally rotated. An active electrode was placed over the belly of the SCM. 100 dB clicks were delivered through headphones. We compared the active contraction and passive positioning of the SCM in terms of the P1 latency and amplitude. RESULTS: Vestibular-evoked myogenic potentials (VEMPs) were recorded without actively contracting the SCMs for all the subjects by using our new method. There was no difference in P1 latency and amplitude between the active contraction and passive positioning of the SCM. CONCLUSION: With our new method, VEMPs can be recorded without actively contracting the SCM. It may be useful for evaluating the vestibular function of children and patients who cannot cooperate.