Cerebral Angiography: Characteristics, Preparation and Risks of the Test

Find out all about the test called a cerebral angiography in this article.

Written and verified by the doctor Mariel Mendoza.

Last update: 25 January, 2023

Cerebral angiography is a minimally invasive medical imaging study that uses a catheter, X-ray guidance and the injection of contrast material to evaluate the blood vessels in the brain. This study, due to the presence of the catheter, makes it possible to combine diagnosis and treatment in the same procedure.

The evaluation of the blood vessels in the brain makes it possible to identify abnormalities such as aneurysms, narrowing, and the presence of clots. This study is subsequently evaluated by the radiologist.

What does cerebral angiography consist of?

Cerebral angiography is also known as “angiogram”. In this procedure, an intravenous contrast material is introduced through the catheter, which reaches the blood vessels in the neck and brain. This, through the images obtained by ionizing radiation (X-rays), allows visualization of cerebral blood flow.

Cerebral angiography procedure

Cerebral angiography uses a contrast material, usually iodine, X-rays, and a catheter. The procedure begins with the person lying on the X-ray table and the head immobilized. Cardiac activity must always be monitored throughout the examination, so it will be connected to an electrocardiogram with the use of different electrodes.

For cerebral angiography, a sedative may be administered before starting the procedure to relax the person. Once sedated, the catheter is inserted. It’s usually placed in the groin, but may also be placed in the arm.

The catheter allows contrast dye to be introduced into the blood vessels in the neck and head. In this way, it provides images of how blood flows through the brain.

In the groin, a local anesthetic is used so that a hole can be opened to fit the catheter. The catheter used in cerebral angiography is a thin, hollow tube that’s introduced through the artery, crossing the vessels in the abdominal and thoracic area, until it reaches the artery in the neck. Subsequently, its position is corroborated by X-rays.

When the catheter is properly positioned, a contrast medium is injected through the artery into the blood vessels of the brain, and then X-rays are taken.

At the completion of the imaging procedure, the needle and catheter are removed and pressure is immediately applied to the catheter insertion area for 10 to 15 minutes.

After the bleeding has stopped, a compression dressing should be applied to the insertion site. To avoid complications, all medical instructions should be followed at the end of the procedure.

Preparation and considerations before the procedure

For 4 to 8 hours prior to cerebral angiography, you mustn’t eat or drink. In addition, you must notify the physician in case of:

• Allergy to shellfish, iodine-containing substances, or any component of contrast media.
• Suspicion of pregnancy.
• History of bleeding or consumption of anticoagulant or antiplatelet medications.
• Any degree of renal function impairment.
• A patient with diabetes (due to possible impairment of renal function).
• Allergy to local anesthetics or general anesthesia.
• Use of steroid drugs.
• Breastfeeding (women who are breastfeeding cannot breastfeed until they have completely excreted the contrast at about 24 hours).

After notifying the doctor of all the medications you are taking, they will tell you which ones you can take on the same day of the procedure and which ones you should stop taking. You should always follow the doctor’s instructions.

After the procedure

Right after the cerebral angiography procedure, you may eat, but rest is recommended for 12 hours before you resume all your normal activities. Because of the likelihood of sedation, you shouldn’t drive to the hospital. Ideally, you should be accompanied by someone.

The leg where the cerebral angiography catheter insertion was performed should be kept extended for 4 to 6 hours after the end of the procedure, as well as monitored for bleeding during the following 12 hours.

Characteristics of cerebral angiography

Currently, the intra-arterial digital subtraction cerebral angiography method is used to acquire the images electronically instead of by X-ray film. This allows the images to be manipulated to remove the bones and tissues that normally obscure the vessels allowing an image to be obtained where the flow within the vessels is clearly seen.

Risks associated with the cerebral angiography procedure

Although complications during and after cerebral angiography are rare, some may occur such as:

• An allergic reaction to the contrast medium.
• Blood clots or bleeding at the catheter insertion site (affecting circulation to the leg or hand).
• Arterial damage from the catheter (may cause blood flow obstruction and cerebrovascular disease).
• Kidney injury from the use of intravenous contrast material.

In case of symptoms such as sudden pain, increase in volume and change of color in the limb where the catheter was inserted or numbness of the same, difficulty in speaking, visual disturbances, facial weakness, or any other symptom of neurological deficit, you should go immediately to the doctor’s office.

When is cerebral angiography recommended?

Cerebral angiography allows you to produce images of the blood vessels in the neck and brain. It is requested when there are signs and symptoms of changes in them:

• Abnormal blood vessels (vascular malformation causing altered blood flow).
• Bulging or protrusion in an artery secondary or weakness of the arterial wall (aneurysm).
• Narrowing of the arteries of the brain (atherosclerosis affecting blood flow to the brain).
• Inflammation of blood vessels in the brain (vasculitis).
• Identifying the location of blood clots in cases of symptoms of cerebrovascular disease.
• Endovascular management of intracranial stenosis, aneurysms and atherosclerotic disease.

It’s also useful for:

• Assessing blood flow to a brain tumor.
• Preparation of medical treatment (interventional radiological procedure) via certain blood vessels.
• Evaluation of head and neck arteries prior to surgery.
• To provide additional information on abnormalities that have been visualized on MRI or brain tomography.

It’s a useful imaging study, although there are other options

Cerebral angiography is requested in cases of suspected alterations in the blood vessels of the brain, and isn’t only beneficial in diagnosis, but also for endovascular treatment. However, there are currently less invasive methods, such as magnetic resonance angiography and computed tomography angiography, which provide clearer images.