Respiratory bronchiolitis,
present histologically in all active smokers, is characterised by the accumulation of pigmented ?smoker’s macrophages? in respiratory bronchioles and neighbouring alveoli, containing granular, yellow-brown cytoplasmic pigments

https://pubs.rsna.org/doi/full/10.1148/radiol.13120908

https://pubs.rsna.org/doi/full/10.1148/radiol.13120908
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