SUMMARY 1-Lobes, Fissures, Alveolar disease

-Minor fissure divides upper from middle lobe on right

-Major fissures mark anterior boundary of lower lobes on both sides

-Use both frontal and lateral views to determine lobar disease location

-Hallmarks of alveolar disease (such as pneumonia)-hazy margins (unless bounded by a fissure), air-bronchograms

Normal distal bronchi are not visible on CT, since normal bronchi are filled with black air and surrounded by black air in lung. Peripheral bronchi may be seen on CT if they are NORMAL but if the lung around them is ABNORMAL (air bronchograms)

With AIRSPACE DISEASE, the density of the abnormality obscures normal lung structures, leaving only dark, air-filled bronchi visible

NORMAL

AIRSPACE DISEASE