[The significance of x-ray images of the thorax--from description to diagnosis].

The X-ray image remains unchanged as the primary diagnostic tool in clinic and practice. It provides decisive diagnostic information to enable the evaluation of many acute and chronic diseases. It is required in almost all medical disciplines. Due to the increase in the use of other radiological procedures, the knowledge of how to arrive at a diagnosis from an X-ray image is being neglected, especially as no instructions and rules are provided for this purpose. Therefore this article will point out the numerous possible uses of X-rays and, based on a special system, the Double Basis Description System (DDS), it will explain how to read an X-ray image of the thorax correctly and arrive at the right diagnosis.