Mumenthaler M, Lütschg J
Schweiz Arch Neurol Neurochir Psychiatr. 1976;118(1):23-56.
Based on 60 of our own cases and on the medical literature the authors discuss the diagnostic, pathophysiological and therapeutic aspects of myasthenia gravis. Myasthenia is suspected in cases of motor weakness of changing intensity, diminishing by rest. The weak muscles are innervated by different peripheral nerves. At the beginning a weakness of upperlid-muscles, external eye muscles and bulbar muscles is particularly frequent. There is no sensory loss or other neurological symptoms. A transitory disappearance of motor weakness after an intravenous dose of Edrophonium (Tensilon) is a typical diagnostic sign. The effect is less evident with eye-muscle weakness. A typical appearance of potentials after repetitive stimulation of peripheral nerves as well as other characteristics in electrophysiological testing of muscles are of high diagnostic value. This allows differentiation from other types of muscle weakness. In the pathogenesis of myasthenia an autoimmune process related to a persistent thymus gland plays an important part. This leads to an ultrastructural change in the postsynaptic membrane of the muscle fibre. The postsynaptic membrane no longer reacts in a normal way to acetylcholine as a transmitter substance at the level of the motor endplate. Therefore the first step in the treatment of myasthenia consists of cholinesterase-inhibitors, specially Neostigmin (Prostigmin) and Pyridostigmin (Mestinon). Thymectomy is advised in all cases of myasthenia with the exception of the pure ocular form and of myasthenia in patients older than 60 years. The thymus gland is practically always persistent or hypertrophic in myasthenia. The suprasternal access is recommended. A thymoma should always be operated upon because of the danger of malignancy. In cases where thymectomy is not performed or not successful and if cholinesterase-inhibitors are not sufficiently efficient, treatment with corticosteroids or ACTH is recommended.
基于作者自身的60个病例以及医学文献，探讨了重症肌无力的诊断、病理生理及治疗方面的问题。重症肌无力疑似于运动性肌无力强度变化且休息后减轻的病例。受累肌肉由不同的周围神经支配。起初，上睑肌、眼外肌和延髓肌的无力尤为常见。无感觉丧失或其他神经症状。静脉注射依酚氯铵（腾喜龙）后运动性肌无力短暂消失是典型的诊断体征。眼肌无力时该效应不太明显。周围神经重复刺激后电位的典型表现以及肌肉电生理测试中的其他特征具有很高的诊断价值。这有助于与其他类型的肌无力相鉴别。在重症肌无力的发病机制中，与持续存在的胸腺相关的自身免疫过程起重要作用。这导致肌肉纤维突触后膜的超微结构改变。突触后膜在运动终板水平不再以正常方式对作为递质的乙酰胆碱起反应。因此，重症肌无力治疗的第一步包括使用胆碱酯酶抑制剂，特别是新斯的明（普洛斯的明）和吡啶斯的明（美斯的明）。除单纯眼肌型和60岁以上患者的重症肌无力外，建议对所有重症肌无力患者行胸腺切除术。在重症肌无力中，胸腺几乎总是持续存在或肥大。推荐采用胸骨上入路。由于有恶变风险，胸腺瘤应始终进行手术。在未进行胸腺切除术或手术不成功且胆碱酯酶抑制剂疗效不佳的情况下，建议使用皮质类固醇或促肾上腺皮质激素进行治疗。
