"The typical histological correlate of honeycombing is advanced traction bronchiolectasis surrounded by alveolar collapse 9. Pathologists regard honeycomb cysts as collapsed cystic secondary lobules lined by respiratory epithelium 12. Cysts are typically connected to airways by a slit-like orifice and flap which suggests the role of a check- valve mechanism in cyst growth. Rapid pre-terminal cyst growth has been reported with autopsy correlation 14."
"Honeycombing and traction bronchiolectasis can be difficult to distinguish, but this is not surprising since traction bronchiolectasis is thought to progress to honeycombing. Honeycomb cysts are usually similar in size,"
"differentiation of honeycombing from emphysematous spaces with peripheral fibrosis can be difficult and the two conditions may coexist; the distribution is helpful, honeycombing is posterior lower zone predominant whereas emphysema with fibrosis is upper zone predominant 12"
"pathologists may find the diagnosis of honeycombing difficult as it can be difficult to distinguish from traction bronchiectasis; a clear histological definition would facilitate imaging evaluation 12"