Centrilobular opacities in the lung on high-resolution CT: diagnostic considerations and pathologic correlation.

Accurate assessment of high-resolution CT scans of the lung requires a knowledge of secondary lobular anatomy. Opacity that localizes to the centrilobular region implies the presence of a disease process that primarily involves centrilobular bronchioles, lymphatics, or pulmonary arterial branches. We illustrate the high-resolution CT findings of many of these processes and provide pathologic correlation for cases in which it was available.