Acinar Pattern

The acinar pattern is representative of airspace disease. Seen are ill-defined, round or elliptical nodules measuring 4–8 mm. They have a characteristic “fluffy” appearance and may take on a patchy distribution, with a later tendency to coalesce into a lobar or...

Rotation

To assess rotation of the film, compare the distance between a spinous process to each of the clavicles. If the supinous process is closer to one clavicle, that side is rotated posteriorly.