If there are still symptoms of chest tightness after the pneumothorax has recovered, it is possible that the body has not fully recovered, or that the pneumothorax is recurring or that there is another lung disease. Pneumothorax is a disease in which gas accumulates in the chest spontaneously or after trauma, and generally speaking, the symptoms of chest tightness do not appear after complete recovery from pneumothorax. Therefore, if the symptoms of chest tightness occur even after the patient has been treated for pneumothorax, consider the following situations: 1. Pneumothorax is not completely recovered, the body is still in the recovery period, the trauma of the chest is not completely healed or there is still a small amount of gas in the chest that has not been absorbed or discharged. 2. Since pneumothorax has recurrence, there is also a possibility that pneumothorax recurs after healing leading to chest tightness. 3. Chest tightness may be caused by heart or respiratory diseases other than pneumothorax. If there are still symptoms of chest tightness after treatment of pneumothorax, the above three cases are considered more often, and it is recommended that the patient go to the hospital as soon as possible, and the professional doctor will carry out the relevant examination and operation to help clarify the cause, so as to avoid delaying the condition.