Images from 16-slice spiral computed tomography (CT). The standard algorithm generated transverse images: width of the lung window, 1000 Hounsfield units (HU); window level, − 700 HU. The 12-mm-thick axial maximum intensity projection-rendered image of the upper segment of the left major fissure shows decreased density of multiple shadow lines and the surrounding structures overlapping with multiple shadow lines, with most of the shadow lines being no longer visible (white arrow). Segmented small blood vessels are visible (white arrowhead)