Huffmann G
Fortschr Med. 1979 Mar 8;97(9):380-4.
The function of the facial nerve can be examined by four electrodiagnostic methods. In the nerve excitability test and electroneurography with determination of the distal latency the facial nerve is stimulated over the stylomastoid foramen. Chronaximetry and electromyography are performed in the muscles. Whereas chronaximetry renders an impression of the severity of neural lesion, electromyography can also determine the onset of reinnervation activity. Early prognosis within 6 days of onset can be determined only by nerve excitability test and electroneurography, preferred by us, which assesses the muscle potential. If the potential amplitude decreases more than 35% within two days and the muscle potential disappears between the fourth and sixth day, total degeneration of the nerve with poor prognosis is indicated. Such data can be gathered by at least two electrodiagnostic investigations preferably on the third day after onset and one to three days later. The cosmetic disfigurement through peripheral facial nerve palsy poses immediately the question of prognosis and of the therapeutic possibilities. Usually, this question can be answered by clinical examination alone. As soon as paralysis of facial muscles exists, prognostical statements can be made by electrodiagnostical methods alone. Because of the possiblility of operative treatment it is necessary to assess the infavorable courses early.
面神经功能可通过四种电诊断方法进行检查。在神经兴奋性试验和测定远端潜伏期的神经电图检查中，面神经在茎乳孔上方受到刺激。时值测定法和肌电图检查则在肌肉中进行。时值测定法能让人了解神经损伤的严重程度，而肌电图检查还能确定神经再支配活动的开始时间。发病6天内的早期预后只能通过神经兴奋性试验和神经电图检查来确定，我们更倾向于采用评估肌肉电位的方法。如果在两天内电位幅度下降超过35%，且在第四至第六天肌肉电位消失，则表明神经完全变性，预后不良。这些数据至少可通过两次电诊断检查收集，最好在发病后第三天及之后的一至三天进行。周围性面神经麻痹导致的面部容貌损毁立刻引发了预后及治疗可能性的问题。通常，仅通过临床检查就能回答这个问题。一旦面部肌肉出现麻痹，仅靠电诊断方法就能做出预后判断。由于存在手术治疗的可能性，有必要尽早评估不良病程。
