[The vestibulocollic reflex: assessment and characteristics of vestibular-evoked myogenic potentials analysed by age groups].
BACKGROUND
Obtaining vestibular-evoked myogenic potentials (VEMP) by means of the vestibulocollic reflex is a readily available technique that provides an image of vestibular functioning and is useful for evaluating the pathologies that involve compromise of the anatomical pathway of the reflex. Although normal patterns do exist, responses vary at different ages.


OBJECTIVE
To obtain reference values of the vestibulocollic reflex according to different age groups.


METHODS
We studied 40 volunteers with no symptoms of auditory or vestibular compromise. Each ear was stimulated separately by a series of clicks (sounds lasting 0.1 s; 3 pps; intensities of 100 dB nHL and 85 dB nHL) and recordings were made in the sternocleidomastoid muscles by means of surface electrodes as patients who were lying on their backs contracted these muscles as they lifted their heads. We studied the latency of the initial p13-n23 positive-negative potential and the peak-to-peak amplitude. The existence of later n34-p44 potentials was evaluated.


RESULTS
No statistically significant differences were found between genders or between the two ears. We did not find any differences between the latencies of the waves according to the intensity of the stimulus, but there is a relationship between the amplitude of the p13-n23 potential and the intensity of the stimulus. The latencies of the responses in children under 10 years of age differ from those of the other groups, but no differences were found among those over the age of 11.


CONCLUSIONS
The VEMP display steady and easily identifiable latencies. We obtained different reference values for latency in children under the age of 10 and those over 11 years old. The amplitude decreases with the intensity of the stimulus.
Gonzalez-Garcia
E
E
Servicio de Neurofisiología Clínica, Valencia, Spain. gonzalez_emi@gva.es
Piqueras-Del Rey
A
A
Martin-Alba
V
V
Parra-Escorihuela
S
S
Soler-Algarra
S
S
Chumillas
M J
MJ
Perez-Guillen
V
V
Perez-Garrigues
H
H
Morera-Perez
C
C
D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D004576:Electromyography; D005072:Evoked Potentials, Auditory; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D008875:Middle Aged; D009334:Neck Muscles / Q000378:metabolism; D012022:Reflex, Acoustic; D014722:Vestibule, Labyrinth / Q000502:physiology*