Chen Yu-ping, Wang Wei, Wei Dong-ning
Department of Neurology, Center for Myasthenia Gravis, No. 309 Hospital of PLA, Beijing 100091, China.
Zhonghua Yi Xue Za Zhi. 2011 May 10;91(17):1178-80.
To explore the value of low-frequency repetitive nerve stimulation (RNS) in the diagnosis of myasthenia gravis (MG).
A total of 436 MG patients admitted during the period of July 2008 and August 2010 and undergoing the repetitive nerve stimulation test were reviewed retrospectively. We analyzed the positive rates of RNS in MG patients and compared the abnormalities in different nerves including facial, accessory, axillary and ulnar nerves.
Among them, 73.85% had abnormal recordings on low-frequency RNS test. The highest abnormality was in facial nerves (82.30%), then axillary nerves (52.17%) and the lowest in ulnar nerves (27.64%). The positive rates of RNS in ocular MG were significant lower than those in general MG patients. And there were no significant statistical differences of RNS abnormal rates in types IIa, IIb, III and IV MG patients with 89.66%, 82.56%, 91.67% and 83.33%, respectively. In ocular MG, 16.34% patients were positive in RNS test under the stimulation of accessory, axillary and ulnar nerves. And 79.50% patients with general MG had two or more nerves with abnormal results.
The low-frequency RNS test is of great value in the diagnosis of MG. And it shows a higher sensitivity in general MG patients than that in ocular ones. The stimulation of facial and axillary nerves increases the positive rates of RNS in MG patients.
探讨低频重复神经电刺激（RNS）在重症肌无力（MG）诊断中的价值。
回顾性分析2008年7月至2010年8月期间收治的436例接受重复神经电刺激试验的MG患者。分析MG患者RNS的阳性率，并比较不同神经（包括面神经、副神经、腋神经和尺神经）的异常情况。
其中，73.85%的患者低频RNS试验记录异常。异常率最高的是面神经（82.30%），其次是腋神经（52.17%），最低的是尺神经（27.64%）。眼肌型MG患者RNS的阳性率显著低于全身型MG患者。IIa型、IIb型、III型和IV型MG患者的RNS异常率分别为89.66%、82.56%、91.67%和83.33%，差异无统计学意义。在眼肌型MG中，16.34%的患者在副神经、腋神经和尺神经刺激下RNS试验呈阳性。全身型MG患者中有79.50%的患者两条或更多神经结果异常。
低频RNS试验对MG的诊断具有重要价值。其在全身型MG患者中的敏感性高于眼肌型MG患者。刺激面神经和腋神经可提高MG患者RNS的阳性率。
