Lateral chest radiograph a systematic approach.

The lateral chest radiograph is a valuable source of information that has become increasingly undervalued in the era of chest computed tomography. Optimal use of the lateral radiograph requires systematic analysis. First is an overview, followed by analysis of the airway and major hilar structures. Next is attention to the three areas where the image darkens in the absence of visible structure edges. Last is attention to the periphery and the upper abdomen. This communication outlines the systematic analysis and then explains in more detail the value of the critical features of that analysis.