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Figure 6. Honeycombing
Axial, sagittal, and coronal CT images show subpleural predominant, lower lung predominant reticular
abnormality with honeycombing (arrowheads). Honeycombing is defined by clustered, thick-walled, cystic
spaces of similar diameters, measuring between 3–10 mm but up to 2.5 cm in size. e size and number of
cysts oen increases as the disease progresses. Oen cited as being layered in the literature, a single layer of
subpleural cysts is also a manifestation of honeycombing. Honeycombing is an essential CT criterion for
typical ("definite") UIP-IPF pattern when seen with a basal and peripheral predominance. In this pattern,
honeycombing is usually associated with traction bronchiolectasis and a varying degree of ground glass
attenuation.
