重症肌无力是发病隐袭的神经肌肉疾患,以随意肌软弱和疲乏为特点。病因不明,可能的因素有:在神经肌肉接点的乙酰胆硷合成和释放有缺陷,受体蛋白的阻滞,肌膜极化的紊乱,循环中有神经肌肉阻滞物,自家免疫过程或病毒感染。多数病人表现的早期症状牵涉头颈部,因而可能先被耳鼻喉科医师所发现。作者报告175例始发为头颈部症状的重症肌无力,分析了头颈部的初期表现,并讨论其诊断方法。175例的平均年龄54岁,范围6～87岁;男105人,女70人。原发眼症状者99例,包括复视45例,上脸下垂36例,复视加上脸下垂18例。原发口、咽、喉症状者53例,包括吞咽困难(咽下困难、梗噎、反胃)27例,构言困难(鼻音言语、言语不清)22例,发音困难(嘶哑嗓音、气息音,声带软弱和疲乏)4例。还有嚼肌软弱11例,面肌软弱8例,颈肌软弱2例,呼吸困难2例。全部病人的症状轻重起伏,表现互异。在有感染、精神紧张、体力活动时,肌软弱症状加重。自发病到就诊时间为1～90个月,多数病人 Myasthenia gravis is an insidious neuromuscular disorder characterized by weakness and fatigue in voluntary muscles. The etiology is unclear. Possible factors are: deficiencies in acetylcholine synthesis and release at neuromuscular junctions, blockade of receptor proteins, disruption of the myofascial polarization, circulation of neuromuscular blockers, autoimmune processes or viruses infection. Earlier symptoms of most patients’ manifestations involve the head and neck and may therefore be first seen by otolaryngologists. The authors report 175 cases of myasthenia gravis originating for head and neck symptoms, analyzing the initial presentation of head and neck, and discussing the diagnostic methods. The average age of 175 cases was 54 years old, ranging from 6 to 87 years old; there were 105 males and 70 females. 99 cases of primary ocular symptoms, including 45 cases of diplopia, 36 cases of sagging face, diplopia and face sagging in 18 cases. There were 53 cases of primary oral, pharyngeal and throat symptoms, including 27 cases of dysphagia (swallowing difficulties, stapes, nausea), 22 dysarthria (nasal speech, unclear speech), dysarthria (hoarse voice, breathlessness , Vocal cord weakness and fatigue) in 4 cases. There were 11 cases of weak muscles, 8 cases of facial weakness, 2 cases of weak neck, and 2 cases of dyspnea. The symptoms of all patients fluctuated, showing different. In infection, mental stress, physical activity, muscle weakness worsened. Since onset to treatment for 1 to 90 months, most patients