Angiography is an imaging technique that can be used to diagnose pathological changes in blood vessels. For this purpose, a contrast medium is introduced into the blood vessels, so that they are visible on an X-ray image. In this way, for example, vessel narrowings, calcifications or aneurysms are recognized. With the help of a DSA system (digital subtraction angiography), we can perform a so-called CO2 gasangiography. The DSA system is a special, large x-ray machine that allows digital recordings of veins, arteries, the vertebral canal or other organs.