ABSTRACT
Radiography The standard projections for radiographic evaluation of the chest are the posteroanterior (PA) and lateral projections with the patient standing. For patients who are unable to stand, an anteroposterior (AP) upright or supine projection can be obtained. While these are useful alternatives, they are typically less satisfactory because of inferior quality related to shorter focal film distance and greater magnification of the heart. This is important since the diagnostic accuracy of chest radiography is partially influenced by the quality of the images themselves.
