Set 3: air bronchograms on CT

The many branching air-filled bronchi are outlined here in blue.  Again, it is not the bronchi themselves that are abnormal, but the surrounding lung parenchya, which is filled with fluid in the case of CHF.  In this particular example, the alveolar opacities in the lungs were NOT due to CHF, but represented involvement of the lungs with lymphoma.  Just like Kerley B lines, air bronchograms are not specific for any particular diagnosis, but just indicate that the process is filling the alveoli.