Marra T R
Department of Neurology, University of Wisconsin Medical School, Sinai Samaritan Medical Center, Milwaukee 53233.
Clin Electroencephalogr. 1990 Jul;21(3):162-7. doi: 10.1177/155005949002100312.
Although the visual evoked potential (VEP) to an alternating checkerboard stimulus is usually recorded from the occipital midline as an N-P-N complex with a major positive deflection at 100 ms (P100), a wave form exhibiting a P-N-P or "W" morphology is occasionally encountered and its interpretation is the source of some controversy. A retrospective chart review identified 15 patients exhibiting the "W" VEP. This represented 7.6 percent of 197 VEP studies and 5.1 percent of 394 eyes. The response was encountered in 1.7 percent of 57 normal patients and 21.4 percent of 56 patients with definite, probable or possible multiple sclerosis (P less than .001). The "W" response was considered normal in only one patient. Of the remaining 14 cases, 13 had definite, probable or possible MS and one had ischemic optic neuropathy. It is concluded that the "W" VEP is an aberrant response that is rarely seen in normals and may have the same significance as a delayed P100 latency.
尽管对交替棋盘格刺激的视觉诱发电位（VEP）通常是从枕部中线记录为一个N-P-N复合波，在100毫秒处有一个主要的正波峰（P100），但偶尔会遇到呈现P-N-P或“W”形态的波形，对其解读存在一些争议。一项回顾性病历审查确定了15例呈现“W”型VEP的患者。这占197例VEP研究的7.6%，以及394只眼中的5.1%。在57例正常患者中有1.7%出现该反应，在56例明确、可能或疑似多发性硬化症的患者中有21.4%出现该反应（P小于0.001）。只有1例患者的“W”反应被认为是正常的。在其余14例病例中，13例患有明确、可能或疑似多发性硬化症，1例患有缺血性视神经病变。得出的结论是，“W”型VEP是一种异常反应，在正常人中很少见，可能与P100潜伏期延迟具有相同的意义。
