Rosengren Sally M, Nogajski Joseph H, Cremer Phillip D, Colebatch James G
UNSW Clinical School and Prince of Wales Medical Research Institute, Institute of Neurological Sciences, High Street, Randwick, Sydney, NSW 2031, Australia.
Clin Neurophysiol. 2007 Sep;118(9):2112-6. doi: 10.1016/j.clinph.2007.05.068. Epub 2007 Jun 28.
Two recently described tests of the vestibular system, vestibular evoked myogenic potentials (VEMPs) and ocular vestibular evoked myogenic potentials (OVEMPs), test the descending and ascending vestibular brainstem pathways, respectively. We describe a case of a patient in whom these investigations localised the lesion and suggested its nature.
VEMPs (to clicks and short duration galvanic stimulation) and OVEMPs (to clicks) were recorded.
Click- and galvanic-evoked VEMPs were delayed on the left side (by approximately 5-6 ms), and click-evoked OVEMPs were similarly delayed (by approximately 4 ms) following left-sided stimulation. Repeat testing 21 months later showed partial resolution.
The observed delays in evoked potentials suggested a demyelinating lesion. Furthermore, the similarity in delayed responses to neck and extraocular muscles was suggestive of a lesion at the root entry zone of the vestibulocochlear nerve.
VEMPs and OVEMPS may thus provide information about the location and nature of lesions affecting central vestibular pathways.
最近描述的两种前庭系统测试,即前庭诱发肌源性电位(VEMPs)和眼前庭诱发肌源性电位(OVEMPs),分别测试前庭脑干的下行和上行通路。我们描述了一例患者,这些检查确定了病变的位置并提示了其性质。
记录VEMPs(对短声和短持续时间电刺激)和OVEMPs(对短声)。
左侧短声和电刺激诱发的VEMPs延迟(约5 - 6毫秒),左侧刺激后短声诱发的OVEMPs也有类似延迟(约4毫秒)。21个月后重复测试显示部分恢复。
诱发电位的延迟提示为脱髓鞘病变。此外,颈部和眼外肌反应延迟的相似性提示病变位于前庭蜗神经根进入区。
因此,VEMPs和OVEMPs可能提供有关影响中枢前庭通路病变的位置和性质的信息。