Mediastinal diseases include mediastinal tumor, mediastinitis, mediastinal cyst, mediastinal hernia and so on. 1. Mediastinal tumors: â‘ Tumors located in the anterior mediastinum include thymoma, lymphoma, teratoma and retrosternal goiter. Tumors located in the middle mediastinum include enlarged lymph nodes and cystic masses. Neurogenic tumors located in the posterior mediastinum. 2. Mediastinitis: including chronic fibrous mediastinitis and acute purulent mediastinitis. 3. Mediastinal cysts: common diseases include bronchial cysts, esophageal cysts, pericardial cysts and so on. 4. Mediastinal hernia: it can be divided into congenital mediastinal hernia and pathologic mediastinal hernia, and pathologic mediastinal hernia is mostly caused by one side of the pulmonary alveolus, pulmonary atelectasis, tension pneumothorax. The appearance of mediastinal disease, need to go to the hospital in a timely manner for relevant examination, identify the cause of the disease, and actively cooperate with the doctor for targeted treatment.