Honeycombing results from the deposition of dense collagen fibers that destroy the characteristic alveolar structure,5 and is typically representative of end-stage lung disease.7 On HRCT, honeycomb cysts appear as enlarged airspaces that are often irregular in size, share thick walls, and are stacked upon one another. The cysts are typically 3-10 mm in diameter but can be as large as 2.5 cm.5,7 When associated with a pattern of usual interstitial pneumonia typical of idiopathic pulmonary fibrosis, honeycombing typically has a peripheral, basal, and subpleural distribution.45 The percentage of patients with IPF with honeycombing on HRCT varies in the literature, but it is estimated to be observed in one-third to two-thirds of patients.8,9
Idiopathic Pulmonary Fibrosis (an Update) and Progressive Pulmonary Fibrosis in Adults: An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline
Reference
5. Raghu G, Collard HR, Egan JJ, et al. An official ATS/ERS/JRS/ALAT statement: idiopathic pulmonary fibrosis: evidence-based guidelines for diagnosis and management. Am J Respir Crit Care Med. 2011;183:788-824.
7. Hansell DM, Bankier AA, MacMahon H, et al. Fleischner Society: glossary of terms for thoracic imaging. Radiology. 2008;246:697-722.
8. Lynch DA, Godwin JD, Safrin S, et al. High-resolution computed tomography in idiopathic pulmonary fibrosis: diagnosis and prognosis. Am J Respir Crit Care Med. 2005;172:488-493.
9. Silva CI, Muller NL, Lynch DA, et al. Chronic hypersensitivity pneumonitis: differentiation from idiopathic pulmonary fibrosis and nonspecific interstitial pneumonia by using thin-section CT. Radiology. 2008;246:288-297.
45. Raghu G, Remy-Jardin M, Myers JL, et al. Diagnosis of Idiopathic Pulmonary Fibrosis. An Official ATS/ERS/JRS/ALAT Clinical Practice Guideline. Am J Respir Crit Care Med. 2018;198(5):e44-e68.
