Question: What is the subpleural finding on this CT scan and what diagnosis could this suggest?
Radiology 2013 266:3, 936-944
Answer: The answer is honeycoming! All four of the following features on high-resolution CT are consistent with a usual interstitial pneumonia (UIP pattern) which can be seen in idiopathic pulmonary fibrosis (IPF). The four UIP criteria are:
- Subpleural, basal predominance
- Reticular abnormality
- Honeycoming with or without traction bronchiectasis
- Absence of features listed as inconsistent with UIP pattern which are:
- Upper or mid-lung predominance
- Prebronchovascular predominance
- Extensive GGO abnormality (extent > reticular abnormality)
- Profuse micronodules (bilateral, predominantly upper lobes)
- Discrete cysts (multiple, bilateral, away from areas of honeycombing)
- Diffuse mosaic attenuation/air-trapping (bilateral, in three or more lobes)
- Consolidation in bronchopulmonary segment(s)/lobe(s)
Other references:
Raghu, G. et al. An Official ATS/ERS/JRS/ALAT Statement: Idiopathic Pulmonary Fibrosis: Evidence-based Guidelines for Diagnosis and Management. ATS Society Guidelines. Am J Respir Crit Care Med Vol 183. pp 788–824, 2011