年龄因素对直流电刺激诱发的前庭诱发肌源性电位的影响

目的评估年龄因素对直流电刺激(GVS)诱发的颈肌前庭诱发肌源性电位(cVEMP)和眼肌前庭诱发肌源性电位(oVEMP)的影响。方法选择健康志愿者61名(122耳)作为研究对象,22~81岁,平均(45.0±13.8)岁。按年龄分为20~40岁组(26例,52耳)、41~60岁组(24例,48耳)以及>60岁组(11例,22耳),分别记录GVS-cVEMP和GVS-oVEMP。计算GVS-c/oVEMP在不同年龄段的引出率、阈值、潜伏期、振幅、振幅不对称比(interaural amplitude asymmetryratio,IAR),采用SPSS18.0软件进行统计学分析。结果GVS-cVEMP在20~40岁、41~60岁、>60岁年龄段的引出率分别为96.15%、89.58%和95.45%,组间比较差异无统计学意义(P>0.05)。GVS-oVEMP在20~40岁、41~60岁、>60岁年龄段的引出率分别为98.07%、91.67%和72.13%,随着年龄增长逐渐降低(P<0.05)。从参数分析来看,cVEMP的引出率、阈值、p1潜伏期、n1潜伏期、振幅和振幅不对称比在不同年龄组间差异无统计学意义(P>0.05);随着年龄增大,oVEMP的引出率下降、阈值增高、振幅减小(P<0.05),其他参数年龄组间差异无统计学意义(P>0.05)。结论随着年龄的增长,周围前庭系统的功能降低,有可能会对直流电刺激诱发的VEMP产生影响。

Effects of aging on galvanic vestibular stimulation elicited vestibular evoked myogenic potential

Objective To observe the effect of age on cervical vestibular-evoked myogenic potential(cVEMP)and ocular vestibular-evoked myogenic potential(oVEMP)elicited by galvanic vestibular stimulation(GVS)in healthy subjects. Methods Sixty-one healthy volunteers(122 ears)aged 22-81 years(45.0±13.8 years)were recruited as study subjects and divided into three groups according to age: 20-40(26 patients, 52 ears), 41-60(24 patients, 48 ears), and >60(11 patients, 22 ears)years. Each subject underwent both GVS-cVEMP and GVS-oVEMP. The elicit rate, threshold, p1 latency, n1 latency, amplitude, and interaural amplitude asymmetry ratio of both VEMPs were calculated and compared among the age groups. SPSS 18.0 software was used for statistical analyses. Results The elicit rates of GVS-cVEMP were 96.15%, 89.58%, and 95.45% in age groups of 20-40, 41-60, and >60 years, respectively, without any statistically significant difference among groups(P>0.05). However, the elicit rates of GVS-oVEMP were 98.07%, 91.67%, and 72.13% in age groups of 20-40, 41-60, and >60 years, respectively, showing a decreased tendency with growing age(P<0.05). In the parametric analysis, the elicit rate, threshold, p1 latency, n1 latency, amplitude, no amplitude asymmetry ratio of cVEMP were not statistically correlated with age(P>0.05). However, growing age showed decreased elicit rate, increased threshold, and decreased amplitude of oVEMP(P<0.05)but no difference in the n1 latency, p1 latency, or amplitude asymmetry ratio. Conclusion With growing age, the function of peripheral vestibular system decreased, which might affect GVS-cVEMP and GVS-oVEMP.