对１１例重症肌无力（ＭＧ）患儿行胸腺切除术，术后１～１．５个月９例眼睑下垂消失，肌力增强，其中４例术后未应用任何药物，有效率为８２％。病理检查显示患儿均有胸腺增生，无合并良、恶性胸腺瘤者。认为手术切除增生之胸腺是治疗小儿ＭＧ的首选方法 Thymectomy was performed in 11 cases of myasthenia gravis (MG). Nine cases of eyelid ptosis disappeared and muscle strength increased from 1 to 1.5 months after operation. Among them, 4 cases did not receive any medication after operation, and the effective rate was 82% . Pathological examination showed thymus hyperplasia in children, no merger of benign and malignant thymoma. Surgical removal of the thymus is considered the preferred method of treatment of pediatric MG