Figure 5a:

Images show the reticular pattern. (a) CT image of the upper part of lung 8. Linear opacities organized as an interrupted reticular pattern can be seen (white ○). Scale bar = 1 cm. (b) Micro-CT image shows contours of the secondary pulmonary lobule (arrowheads) with a terminal bronchiole and accompanying vessel in the center (white arrow). Linear opacities in a correlate with small islands of increased attenuation (black arrows) adjacent to interlobular septa (arrowheads) in b. Scale bar = 1 mm. (c–e) Close-up images of the outlined area in b. A terminal bronchiole (arrowheads) divides into two first-generation respiratory bronchioles (white arrows). The inferior bronchiole divides into two second-generation respiratory bronchioles (black arrows) that abruptly terminate against an irregular island of increased attenuation.