*'''C'''ardiac: Check both cardiothoracic ratio and any dilation of blood vessels.
*'''D'''iaphragm: Check for any pleural fluid
*'''E'''dges: Check for pneumothorax and , if not already evaluated under C, also Kerley B lines.
<gallery>
File:X-ray subtle pneumothorax in inspiration - annotated.jpg|Subtle pneumothorax, only determined by absence of vascularity in upper left lung region.