Set 2: interstitial edema

Kerley B lines

Kerley B lines are VERY subtle on chest radiographs, so you have to know what they look like and where they are most likely to be. These two images show closeup views of the lower peripheral lung in this same patient. Look in the OUTER lung zone for any parallel horizontal lines. They are NOT supposed to be there! But you have to look closely and carefully to see them!