Boongird P, Vejjajiva A
Muscle Nerve. 1978 Nov-Dec;1(6):461-6. doi: 10.1002/mus.880010604.
Electrophysiologic investigations were carried out on 45 patients with Bell's palsy at periodic intervals after the onset of paralysis. It was found that there was a good correlation between prognosis in Bell's palsy and the amplitude of evoked motor response obtained after six or more days of clinical paresis. When the average amplitude of evoked motor response was within normal limits (i.e., 504 mu V or greater), complete recovery with no residual deficits took place two to six weeks after the onset of facial palsy. When the evoked motor response was absent in all three major branches of the facial nerve, indicating complete nerve degeneration, electromyographic signs of recovery were apparent by the third of fourth month after the onset of paralysis. In these cases, recovery was relatively slow and incomplete, with some degree of residual deficit and synkinesis. Maximal return of voluntary facial movement was established 8 to 12 months after the initial symptom. When the mean amplitude of evoked motor response was below the lower limit of normal (i.e., less than 504 mu V), electromyographic signs of recovery were noted within 1 to 3 months, depending on the amplitude values. The final outcome of this intermediate group was similar, but not identical, to that of the previous group. The prognosis of facial paralysis in Bell's palsy was thus found to be directly related to the mean amplitude of evoked motor response, regardless of the extent of clinical paralysis.
对45例贝尔面瘫患者在面瘫发作后的不同时期进行了电生理检查。结果发现，贝尔面瘫的预后与临床麻痹6天或更长时间后获得的诱发运动反应幅度之间存在良好的相关性。当诱发运动反应的平均幅度在正常范围内（即504微伏或更高）时，面瘫发作后两到六周可完全恢复且无残留缺陷。当面神经所有三个主要分支均未引出诱发运动反应，表明神经完全变性时，麻痹发作后第三个月或第四个月会出现肌电图恢复迹象。在这些病例中，恢复相对缓慢且不完全，存在一定程度的残留缺陷和联带运动。初次出现症状后8至12个月可实现面部随意运动的最大程度恢复。当诱发运动反应的平均幅度低于正常下限（即小于504微伏）时，根据幅度值，在1至3个月内会出现肌电图恢复迹象。这一中间组的最终结果与前一组相似，但不完全相同。因此发现，贝尔面瘫的预后与诱发运动反应的平均幅度直接相关，而与临床麻痹的程度无关。
