Vestibular-evoked myogenic potentials in cochlear implant children.
CONCLUSIONS
Our results suggest that the sacculi of most children with cochlear implants can easily be damaged, as shown by the absence of vestibular-evoked myogenic potentials (VEMPs) in response to click stimuli. Also, in most of the children, the vestibular nerve was seemingly not stimulated by the cochlear implant. These results suggest that electrical stimulation at the C level can stimulate the cochlear nerve; however, this stimulation did not spread to the vestibular nerve in our children. In some children with Mondini dysplasia or vestibulocochlear nerve abnormality, the vestibular nerve was stimulated when the cochlear implant device was on, because of a VEMP response to electrical stimulation.


OBJECTIVE
To clarify the diagnostic value of VEMPs in cochlear implant patients.


METHODS
The click-evoked myogenic potentials of 12 children who underwent cochlear implantation surgery were investigated. The latency and amplitude of the VEMP responses were measured.


RESULTS
Before surgery, 6 of the 12 children showed normal VEMPs, 1 showed a decrease in the amplitude of VEMPs and five showed no VEMP response. After surgery, with the cochlear implant device off, 1 child showed a decreased VEMP and 11 showed no VEMPs. With the cochlear implant device on, four children showed VEMPs and eight did not.
Jin
Yulian
Y
Department of Otolaryngology, Faculty of Medicine, University of Tokyo, Tokyo, Japan. yljin81@hotmail.com
Nakamura
Masako
M
Shinjo
Yukiko
Y
Kaga
Kimitaka
K
D002150:Caloric Tests; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D003054:Cochlear Implants; D007758:Ear, Inner / Q000002:abnormalities; D004576:Electromyography; D019054:Evoked Potentials, Motor / Q000502:physiology*; D005260:Female; D034381:Hearing Loss / Q000534:rehabilitation*; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging; D008297:Male; D012444:Saccule and Utricle / Q000502:physiology; D014057:Tomography, X-Ray Computed; D014725:Vestibular Nerve / Q000503:physiopathology*; D014722:Vestibule, Labyrinth / Q000502:physiology*