Fig. 1.

CT sample images of patients with pneumonia.

(a): A 28-year-old male with confirmed COVID-19 pneumonia. The red arrows indicate ground-glass opacity in the right and left lower lobes.

(b): A 33-year-old female patient with confirmed COVID-19 pneumonia. The red and yellow arrows indicate typical mixed ground-glass opacity-consolidation patterns in both lobes, and a ground-glass opacity pattern in the peripheral right upper lobe, respectively.

(c): An 81-year-old female patient with H1N1 influenza. The red arrows indicate infection with mixed ground-glass opacity and consolidation pattern in both lobes

(d): A 72-year-old male patient with atypical pneumonia. The red arrows indicate ground-glass opacity in the right middle lobe.