What to Know About a Cerebral Angiogram

Medically Reviewed by Sabrina Felson, MD on May 05, 2023
3 min read

A cerebral angiogram checks for abnormalities in the blood vessels of your brain. The procedure has a handful of related names. These include:

  • Carotid angiogram or angiography
  • Cerebral angiogram or angiography
  • Cerebral arteriogram

Cerebral angiography is the process of performing an X-ray on your brain. A cerebral angiogram refers to the X-ray itself. You may see the terms used interchangeably.

A cerebral angiogram is the result of a type of X-ray called cerebral angiography. The X-ray checks the blood vessels and blood flow in your head, brain, or neck by using a special contrast dye.

How it’s done. A catheter is inserted into an artery. It is injected with a contrast dye that spreads through your bloodstream. This causes your blood vessels to be visible in an X-ray.

Your doctor may suggest cerebral angiography to diagnose conditions, locate or identify abnormalities, and minimize complications before surgery. This procedure may be suggested if previous tests didn’t provide conclusive information.

Results. Cerebral angiography can reveal a variety of abnormalities in your blood vessels, such as:

  • Bulging or ballooning of blood vessels: aneurysm
  • Narrowing of your blood vessels: stenosis
  • Narrowing of your arteries: atherosclerosis
  • Inflammation that causes narrowing: vasculitis
  • Abnormal connection or tangle of vessels: arteriovenous malformation
  • Blood clot: thrombosis
  • Blood vessel spasms: vasospasm
  • Total blood vessel blockage


There are extra risks that accompany cerebral angiography since it involves radiation, including:

  • Side effects of radiation exposure if you have a history of X-rays and CT scans
  • Exposure to radiation while pregnant can lead to birth defects
  • Allergic reaction to the contrast dye used for the test
  • Complications caused by conditions or medications that affect blood-thinning or clotting

There is a small risk of the following serious complications involving your blood vessels and brain:

  • Fainting and loss of consciousness
  • Transient ischemic attack (TIA): ministroke
  • Paralysis only on one side of the body: hemiplegia
  • Blood clots: embolus
  • Bleeding or bruising at the puncture site: hematoma 
  • Infection
  • Stroke
  • Loss of speech abilities: aphasia

Cerebral angiography isn’t recommended if you have a condition that affects your kidneys, liver, or thyroid.

Your doctor will explain how cerebral angiography works and will give you time to ask questions. You will then need to sign a consent form for the procedure.

‌Risk factors. Tell your doctor if you have any allergies or sensitivities, are pregnant, have a history of bleeding disorders, or if you are taking blood thinners. Some allergies that may cause complications during this procedure include:

  • Contrast dye
  • Iodine
  • Shellfish
  • Any medications
  • Latex
  • Tape
  • Anesthesia

Food and drugs. Your doctor will likely ask you to fast before the procedure. They may also ask you to stop taking anticoagulants (blood thinners) before the procedure to prevent complications.

Your doctor may provide you with medication to promote relaxation. Have someone give you a ride to the appointment since this will likely make you sleepy.

Additional tests. Your doctor may order additional tests to reduce possible risks during the cerebral angiography. For example, they may perform a blood test to determine the time it takes for your blood to clot.

Relief. Depending on the injection site, you may need to stay flat on a bed for several hours after the procedure. Your doctor may recommend ice or pain medications to relieve pain and swelling during that time.

Diet. You can typically return to your normal diet after the procedure unless your doctor says otherwise. You’ll be encouraged to drink fluids to get the contrast dye out of your body.

Activity. You can typically return to your normal activities within 8 to 12 hours. Your doctor may suggest avoiding strenuous activities for some time.

When to call your doctor. A small bruise or occasional light bleeding at the injection site is normal. But monitor the limbs near the injection site for changes in temperature, abnormal colors, pain, numbness, or loss of function. Call your doctor if any of these changes occur.

You should also call your doctor if you notice any of the following symptoms:

  • Chills or fever
  • Worsening pain, redness, swelling, bleeding, or abnormal drainage from the injection site
  • Changes in speech or vision
  • Dizziness
  • Muscle weakness
  • Chest pain
  • Difficulty breathing