ICM-II: CHEST, case 1

TECHNICAL-no rotation, PA

The best way to tell if an image is PA or AP is to read the label, but again you were not given a label on this image. What else can give you a clue about this?

The clavicular heads (very far anterior in the body) and the spinous processes (very far posterior in the body) are a very sensitive pair of structures that can be used to detect minimal amounts of rotation in the axial plane. If the spinous processes are centered between the clavicular heads (as in this case, shown in yellow) the patient is straight. The blue indicates how much lung is visible above the clavicle, an indication of kyphotic or lordotic positioning. About one interspace of lung should be visible, as in this case. An interspace is the distance from one rib to the next.