Angiography of the eye
Angiography on the eye allows the fine blood vessels of the retina and choroid that run from the inside of the skull to the eyeball to be depicted. Ophthalmologists use the angiographies on the eye in cases of urgent suspicion of damage to the vessels. There are two procedures available for an angiography of the eye vessels.
They differ in the choice of contrast medium. These are fluorescence angiography and indocyanine green angiography. Both contrast media are considered harmless and harmless.
Before the examination, the pupil is first dilated with special eye drops. The pupil is the only opening in the eyeball through which the vascular drawings of the retina can be seen. Then the respective contrast medium is quickly applied via the arm vein.
It only takes a few seconds for the contrast medium to reach the eye. The entire exposure usually takes less than 10 minutes. The most important causes that can lead to damage to the blood vessels in the eye are diabetes, macular degeneration, arteriosclerosis, tumours or inflammation.
In the case of advanced diabetes mellitus, “diabetic retinopathy” can occur. In macular degeneration, especially in old age, there is a loss of vision in the sharpest point of vision. Arteriosclerosis, tumours and inflammations can attack the vascular structures in the eye and reduce or even stop the normal blood flow.
If the adjacent cells are not sufficiently supplied with blood, they die and vision loss would be the result. Angiography of the eye offers a very precise diagnostic possibility to examine the blood supply of the retina. Unfortunately, it does not offer the possibility of direct intervention, for example the removal of a blood clot. It should be noted that the dilation of the pupil for a certain period of time after the operation means that there is a high sensitivity to light.
Angiography of the heart
One of the most frequently used angiographic examinations is performed on the heart. Here, the structures containing blood, i.e. the coronary arteries and the heart‘s interior spaces themselves, with right and left atria and right and left ventricle, are made visible. The examination of the coronary arteries is also called “coronary angiography”.
Since the examination is performed using a long catheter, it is also called “cardiac catheterization”. The catheter is a soft, flexible tube that is slightly pre-bent at the tip to adapt to the shape of the coronary arteries. The catheter is inserted into a more distant artery from the outside.
An artery in the groin or elbow is used for this. The catheter is advanced through the vessel to the heart against the direction of blood flow. It is made of a soft material to avoid damaging the vessel walls.
A catheter can be used to inject contrast medium into the vessels in addition to pressure measurement techniques. In this way, individual coronary vessels can be made visible and their function can be assessed independently of each other. The left ventricle, which pumps the oxygen-rich blood into the large body circulation, can also be enriched with contrast medium.
With simultaneous imaging, the pumping performance of the left atrium and left ventricle can be assessed. Cardiac catheterization via a vein is also possible. It is no longer used too often today.
In this case, it is mainly the right atrium and right ventricle that can be assessed, but also the pulmonary arteries. Angiography of the heart is used to assess the size, shape and pumping capacity of both atria and both chambers. Other changes in the heart, such as tumours, heart defects or calcifications can also be detected.
Coronary angiography in particular is crucial in the diagnosis of reduced blood flow to the heart, which is associated with health complaints. Especially coronary heart disease, angina pectoris and heart attacks are consequences of arteriosclerotic changes. The advantage of angiography on the heart is the direct intervention after diagnosis.
If the coronary vessels are narrowed, it is possible to dilate the vessel with the help of a catheter, for example by inserting a stent. During the procedure one is usually fully conscious. After pulling the catheter out of the arterial vessel, it is especially important to stop the bleeding with a tight pressure bandage. Complications during this procedure are rather rare.
