Weerakkody Y, Silverstone L, Bell D, Interstitial lung abnormality. Reference article, Radiopaedia.org (Accessed on 29 Mar 2024) https://doi.org/10.53347/rID-68888
Interstitial lung abnormality (ILA) refers to incidental bilateral non-dependent CT patterns including reticulation, traction bronchiectasis and honeycombing that may be symptomatic, may progress to fibrosis and portend a higher all cause mortality risk 7.
Although may vary from population to population its general prevalence in a routine cohort of CT older adults (subjects older than 60 years of age) as 4–9% of smokers and 2–7% of non-smokers 6,10.
Terminology
Definition: incidental bilateral non-dependent ground-glass opacity, reticulation, distortion, traction bronchiectasis, honeycombing or non-emphysematous cystic change affecting more than 5% of any lung zone without a demonstrable cause.
50% may progress over 5 years, particularly subpleural and fibrotic changes.
Imaging subclassification
Recent publications (2020-2021) have suggested sub-classification into following types 7,9
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2. Putman R, Hatabu H, Araki T et al. Association Between Interstitial Lung Abnormalities and All-Cause Mortality. JAMA. 2016;315(7):672-81. doi:10.1001/jama.2016.0518 - Pubmed
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6. Hatabu H, Hunninghake G, Lynch D. Interstitial Lung Abnormality: Recognition and Perspectives. Radiology. 2019;291(1):1-3. doi:10.1148/radiol.2018181684 - Pubmed
7. Hata A, Schiebler M, Lynch D, Hatabu H. Interstitial Lung Abnormalities: State of the Art. Radiology. 2021;301(1):19-34. doi:10.1148/radiol.2021204367 - Pubmed
8. Hatabu H, Hunninghake G, Richeldi L et al. Interstitial Lung Abnormalities Detected Incidentally on CT: A Position Paper from the Fleischner Society. The Lancet Respiratory Medicine. 2020;8(7):726-37. doi:10.1016/s2213-2600(20)30168-5
9. Chae K, Jin G, Goo J, Chung M. Interstitial Lung Abnormalities: What Radiologists Should Know. Korean J Radiol. 2021;22(3):454-63. doi:10.3348/kjr.2020.0191 - Pubmed
10. Ledda R, Milanese G, Milone F et al. Interstitial Lung Abnormalities: New Insights Between Theory and Clinical Practice. Insights Imaging. 2022;13(1):6. doi:10.1186/s13244-021-01141-z - Pubmed