First of all, it should be clear that there are four kinds of emphysema in the clinic, as follows: 1, obstructive emphysema: that is, it is often said that the old chronic obstructive pulmonary; 2, compensatory emphysema: for example, the left lung is cut, leaving a right lung, the right lung is compensated; 3, scar emphysema: for example, the left upper lobe just happened to have a small operation, causing scar emphysema; 4, obstructive emphysema: chronic obstructive pulmonary disease is not called emphysema, the cause of the disease, for example, smoking, Physical and chemical factors, occupational diseases, and of course genes, including genetic factors, pulmonary hypoplasia, which is its etiology. Some people smoke all their lives and do not have COPD, while others have COPD in their 40s because of a genetic problem in their body, which may be a lack of an enzyme called α1-antitrypsin. After the lack of this enzyme, the alveoli will be easily dissolved, two small alveoli can become one small alveoli, four become one, gradually leading to the emergence of chronic obstructive pulmonary disease.