The fundamental components of traditional and nontraditional interpretation of lung patterns are very similar. Differences mainly relate to what imaging signs are emphasized as important and choice of terminology. In the nontraditional approach, in lungs with abnormal opacity, the two key signs for prioritizing the differential diagnoses are the degree of lung expansion and the macroscopic distribution of the lung lesion. Additional signs are used, such as the appearance of the opacity, but they are described using terms such as bronchocentric, ground-glass opacity, and consolidation, because they do not indicate a precise histologic classification.