PubMed1979
Roentgenography is the simplest and most reliable means to arrive at the diagnosis of chest injury. General roentgenograms are difficult to interpret as they tend to be technically imperfect. Fractures, emphysema, pneumothorax, accumulation of fluid can usually be ascertained directly; but the traumatic origin of changes in the pulmonary parenchyma or of an enlarged heart shadow cannot be reliably deduced from the X-ray appearance. It may provide some differential-diagnostic information but the correct interpretation of the findings depends on further observation. In 6-7% of severe chest trauma with vascular injuries and rupture of the diaphragm angiography is indicated. The evidence to be obtained from chest radiography should not be overestimated: fractures of ribs are sometimes overlocked, even by the expert; parenchymatous lesions may manifest themselves as shadows but their nature remains obscure until they have been related to the clinical and subsequent radiological findings. The same applies to rupture of the diaphragm, bronchi or vessels, if only the immediate posttraumatic roentgenographs are examined. A tent-shaped heart shadow is considered characteristic of the presence of fluid in the pericardium; this is valid only for chronic hydropericardium, but not for the potentially fatal cardiac tamponade; if the pericardium has lost its elasticity a haemorrhage of not more than 150 ml may prove fatal. Nor does the roentgenogram provide information about pulmonary function. Especially in cases of pulmonary shock minor changes in the chest roentgenogram may give a false sense of security when, in fact, blood gas analyses show that a life-endangering situation has developed. The radiologist who is aware of the limititations of the method will derive maximum diagnostic benefit from a chest angiography. No other method is capable of supplying information of such great importance in such a short time.