Enlargement of the right lung can be seen in the following cases: 1. The right lung itself is enlarged, which can be seen in the right lung lesions, such as lung tumors, restrictive emphysema, etc., the mediastinum is shifted to the left, and the right lung can appear to be enlarged. 2. The left lung is reduced in size, if the left lung is atrophied, the reduced volume can cause the mediastinum to be shifted to the left, and the right lung appears to have compensated emphysema, so that the right lung is larger. If the right lung is found to be enlarged in the radiographs or chest CT, it should be clear whether the patient has any other lesions, and bronchoscopy and other tests can be done to further clarify.