Part I Radiological Signs -- 1 Beaded Septum Sign -- 2 Comet Tail Sign -- 3 CT Halo Sign -- 4 Galaxy Sign -- 5 Reversed Halo Sign -- 6 Tree-in-Bud Sign -- 7 Gloved Finger Sign or Toothpaste Sign -- 8 Lobar Atelectasis Sign -- 9 Air-Crescent Sign -- 10 Signet Ring Sign -- Part II Focal Lung Diseases -- 11 Nodule -- 12 Mass -- 13 Consolidation -- 14 Decreased Opacity with Cystic Airspace -- 15 Decreased Opacity without Cystic Airspace -- Part III Diffuse Lung Diseases -- 16 Interlobular Septal Thickening -- 17 Honeycombing -- 18 Small Nodules -- 19 Multiple Nodular or Mass(-like) Pattern -- 20 Ground-Glass Opacity with Reticulation -- 21 Ground-Glass Opacity without Reticulation -- 22 Consolidation -- 23 Decreased Opacity with Cystic Walls -- 24 Decreased Opacity without Cystic Walls -- 25 Decreased Opacity without Cystic Airspace: Airway Disease -- Part IV Application of Disease Pattern and Distribution, and Radiologic Signs to the Differentiation of Various Lung Diseases -- 26 Pneumonia Including COVID-19 -- 27Drug-Related Pneumonitis -- 28 Interstitial Lung Disease in Connective Tissue Disease.