All of the abnormalities have air density within at least a portion of them. In describing cystic lung disease, consider:

SIZE

SHAPE

WALL THICKNESS

B

C

SIZE - small, 1-2 cm

SHAPE - round, tubular and branching

WALL THICKNESS - thin and uniform

SIZE - large, over 10 cm

SHAPE - rounded

WALL THICKNESS - very thin, almost invisible

SIZE - large, over 5 cm

SHAPE - slightly irregular

WALL THICKNESS - thick and irregular, contains air-fluid level

A