[Imaging phenotypes of chronic obstructive pulmonary disease based on biphasic quantitative CT features].

=6). Patients with the same Global Initiative for Chronic Obstructive Lung Disease (GOLD) grade had similar degree of airflow limitation, but the lesion components were not identical. Being different from the traditional imaging classification, even in the cases of mild emphysema, they can be further divided into small airway disease-dominant type and bronchial wall thickening-dominant type according to the difference of airway disease.