[Vestibular potentials evoked by electrical stimulation].
OBJECTIVE
To identify the evoked potentials (VsEPs) by electrical stimulation were from vestibule.


METHODS
The stimulating electrode was set on the round window of guinea pig. Constant current shocks of 0.05 ms (0.25-1.2 mA) were used to evoke VsEPs by means of vertex-pinna skin electrodes.


RESULTS
These potentials were short latencies of (0.973 +/- 0.086) ms, (1.618 +/- 0.176) ms and (2.416 +/- 0.274) ms respectively, which reflected true potentials and were not from electrical stimulus artefacts. It was pure vestibular origin. As being masked with a continuous white noise (120 dB SPL) or removed ipsilateral auditory nerve, and even after facial neurectomy, waves were still existing, but disapeared after selective vestibular neurectomy. The twitching responses in the facial region had never been detected during the whole test. These potentials were bioelectric responses in the vestibular sensory pathway, characterized by threshold saturation, adaptability of excitation, dependent on intact vestibular nerve.


CONCLUSIONS
We have set up animal model of recording VsEPs evoked by electrical stimulation on the round window of guinea pigs.
Jiang
Z
Z
Department of Otorhinolaryngology, PUMC Hospital, CAMS and PUMC, Beijing 100730.
Zhang
L
L
Ni
D
D
Cao
K
K
Wang
Z
Z
D000818:Animals; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000502:physiology; D005260:Female; D006168:Guinea Pigs; D008297:Male; D014722:Vestibule, Labyrinth / Q000502:physiology*