 Centrelobular emphysema, CLE, and Paraceptal emphysema, PSE, are both commonly found in smokers with preserved ratio-impaired spirometry, prism, but they have distinctly different effects on lung function. CLE is more likely to be associated with air trapping, while PSE is less likely to be associated with air trapping. This article was authored by Yusuka Shirashi, Tokafumi Shimoda, Naoya Tonabe, and others.