Iwasaki S, Chihara Y, Smulders Y E, Burgess A M, Halmagyi G M, Curthoys I S, Murofushi T
Department of Otolaryngology, Faculty of Medicine, University of Tokyo, Tokyo, Japan.
Clin Neurophysiol. 2009 Mar;120(3):588-93. doi: 10.1016/j.clinph.2008.12.036. Epub 2009 Feb 10.
The n10 component (n10) of the ocular vestibular evoked myogenic potential (oVEMP) to brief bone conducted vibration (BCV) of the forehead at Fz is probably caused by the vibration selectively activating vestibular otolithic receptors. If the n10 is due primarily to utricular activation then diseases which affect only the superior division of the vestibular nerve (SVN) should reduce or eliminate n10.
The n10 component of the oVEMP was measured in 13 patients with unilateral SVN but with inferior vestibular nerve function preserved.
We compared the n10 to BCV of these 13 SVN patients to previously published data for healthy subjects and patients after complete unilateral vestibular loss. We found that in 12 out of the 13 patients with SVN, n10 was markedly reduced or absent under the contralesional eye.
Since all utricular afferents course in the superior vestibular nerve and in 12/13 of these patients the n10 was reduced we conclude that the n10 component of the oVEMP to BCV is probably mediated by the superior vestibular nerve and probably due to activation of mainly utricular receptors.
The n10 appears to be a simple new test of superior vestibular nerve and probably mainly utricular function.
眼部前庭诱发肌源性电位（oVEMP）的n10成分是在Fz处对前额进行短暂骨传导振动（BCV）时产生的，它可能是由该振动选择性激活前庭耳石感受器所致。如果n10主要是由于椭圆囊激活引起的，那么仅影响前庭神经上部分（SVN）的疾病应该会减少或消除n10。
对13例单侧SVN但保留了前庭神经下部分功能的患者测量oVEMP的n10成分。
我们将这13例SVN患者的n10与BCV数据与之前发表的健康受试者和单侧前庭完全丧失患者的数据进行了比较。我们发现，在13例SVN患者中的12例中，患侧眼下方的n10明显降低或消失。
由于所有椭圆囊传入神经都走行于前庭神经上部分，且在这些患者中有12/13的患者n10降低，我们得出结论，oVEMP对BCV的n10成分可能由前庭神经上部分介导，可能主要是由于椭圆囊感受器的激活。
n10似乎是一种简单的前庭神经上部分以及可能主要是椭圆囊功能的新测试方法。
