Studies for clinical use of olfactory evoked potentials by electrical stimulating olfactory mucosa

外科医生在前颅窝附近手术后，一些患者会失去嗅觉功能。然而，对日常生活同样重要的嗅觉功能的客观评估方法还没有开发出来。通过电刺激狗和人的嗅黏膜获得的嗅觉诱发电位(OEP)被记录下来，以建立一种客观的评估嗅觉功能的方法。在狗身上，记录了嗅束和头皮的OEPS。第一个负峰的潜伏期约为40毫秒。刺激鼻粘膜后无反应，切断嗅神经后消失。随着重复刺激频率的增加，波幅降低，提示该反应是由突触介导的。这些结果表明，电刺激嗅黏膜后，来自嗅束和头皮的诱发电位特异性地起源于嗅觉系统。在人类身上，一个带有软导尿管的刺激电极固定在嗅黏膜上。嗅束的OEP被记录下来，在大约27毫秒处有一个负峰值，这与狗的特征相似。人类嗅束的OEP也特别起源于嗅觉系统。通过电刺激嗅黏膜获得的OEP可能被证明对术中监测嗅觉功能有用。

Following surgeon near the anterior fossa, some patients experience loss of olfactory functions. However, objective methods for evaluating olfactory functions, which are also important for daily living, have not yet been developed.The olfactory evoked potential (OEP) obtained by electrical stimulation of the olfactory mucosa was recorded in dogs and humans to develop an objective method for evaluating olfactory functions. In dogs, OEPs were recorded from the olfactory tract and the scalp. The latency of the first negative peak was approximately 40 msec. A response was not obtained following stimulation of the nasal mucosa and disappeared following sectioning of the olfactory nerve. With increasing frequencies of repetitive stimulation, the amplitude was reduced, suggesting that the response was synaptically mediated. These results demonstrate that evoked potentials from the olfactory tract and the scalp following electrical stimulation of the olfactory mucosa originate specifically from the olfactory system. In humans, a stimulating electrode with a soft catheter was fixed on the olfactory mucosa. The OEP from the olfactory tract was recorded with a negative peak at approximately 27 msec, similar to characteristics found in dogs. The OEP from the olfactory tract in humans also originates specifically from the olfactory system. The OEP obtained by electrical stimulation of the olfactory mucosa may prove useful for intraoperative monitoring of olfactory functions.