Angiography

Angiography is a diagnostic procedure carried out by assistance of an MRI system, CT or a digital subtraction angiography device (DSA) for the depiction of vessels. MR angiography can take place with or without the application of a contrast agents, whereas CT or digital subtraction angiography necessitate the application of a contrast agent.

At the beginning of a digital subtraction angiography, an X-ray image without a contrast agent is taken. During and after the following contrast agent application, several further images are taken. The procedure is called digital subtraction angiography because the digitally taken images without a contrast agent are subtracted from the images depicting the vascular status with a contrast agent. This way elements of the images are removed that are not necessary for the evaluation or that would make it difficult to evaluate the images, for example, bones.

Indication angiography: when is angiography carried out?

Angiography takes place if vascular diseases seem to be the cause of complaints. During angiography, veins, arteries, lymph vessels or vascular prostheses can be examined. Examples for the indication of angiography are:

• vascular stenosis (e.g., throat vessels / carotid stenosis)
• aneurysm
• vascular damage
• vascular malformation

Course digital subtraction angiography

It is crucial to assess if the patients undergoing an angiography examination have a blood coagulation disorder / coagulopathy (blood test), an allergy to contrast agents, an illness making the performance of an angiography difficult or impossible, or if they take drugs manipulating the angiography.

At the day of the examination, patients have to have an empty stomach and are not allowed to smoke for a couple of hours prior to the examination. After a skin disinfection and local anesthesia, if necessary, the contrast agent is injected directly into a vessel or through a catheter guided to the vessel to be examined. In case of a catheter application, also therapeutic procedures are possible, for example, vascular dilatation by a balloon, stent placement or glue usage for the repair of damaged vessels.

At the end of the examination / treatment, the wound is sterilely covered. Subject to the examination / treatment, it can be necessary that patients do not stand up but lay low and stay one day for observation.