Fig. 2

A typical case of occult pneumothorax diagnosed by OXR. This 58-year-old woman was involved in a head-on car accident and arrived with dyspnea, right chest pain. a Anteroposterior supine radiograph shows no abnormality. b OXR on the right clearly reveals a distinct visceral pleural line (arrowheads). c CT scan proves the existence of an occult pneumothorax on the right side. d Supine oblique chest radiographs could be easily performed in a trauma resuscitation area