A cerebral angiogram (or arteriogram) is a diagnostic test that produces images of the arteries in the brain and/or head and the blood flowing through them. It can help physicians diagnose a number of problems with the blood vessels in the head and neck, including ruptured vessels or blockage of an artery, usually by fatty plaque. If a vessel is blocked, the patient may be at increased risk of stroke. Other conditions (such as a cerebral aneurysm) may also be revealed through a cerebral angiogram.

To perform an angiogram, the physician injects a special dye (contrast medium) into the arteries of the head or brain through a long, thin tube called a catheter. The catheter is threaded through a blood vessel, usually in the upper thigh and into the head. Once the catheter is in place, the physician injects the dye through the catheter and into the targeted arteries. After the dye has reached the arteries, the x-ray images can be taken.

Although the physician typically numbs the area where the catheter is inserted, the patient is awake for the entire procedure. The patient receives a mild sedative before the procedure and usually does not feel the movement of the catheter within the blood vessels. However, there may be some sensation, such as heat or flushing, as the dye is released.

Preparations for the test may vary and patients are encouraged to discuss the matter with their physicians. The test is usually performed on an outpatient basis and patients generally return home the day of the test. They may be  placed on bed rest for 24 hours following the procedure. In some cases, patients will remain in the hospital for observation or further tests.

The most common risk associated with cerebral angiograms is an allergic reaction to the contrast medium. Patients should inform their physicians of any known allergies, especially to iodine, shellfish or strawberries. There is also a risk that the catheter will rupture an artery or dislodge a piece of plaque that can block blood flow and cause a stroke. Women who are pregnant or trying to become pregnant or who are nursing need to discuss the use of this test with their physicians. Angiograms are usually not done on pregnant women due to the risk of damage to the fetus by radiation.

A cerebral angiogram (or arteriogram) is a diagnostic test that produces x-ray images of the arteries in the brain and/or head. The contrast medium (dye) that is used in the test can produce images of arteries and blood vessels as well as blood flow. It is very similar to a coronary angiogram, except that it is of the blood vessels of the head and neck rather than of the heart. Cerebral angiograms are used to diagnose conditions in the blood vessels of the brain, head, neck and back. They can aid in the detection of the following conditions within the brain:

While CAT scans and MRIs are more commonly used to diagnose and monitor the treatment of brain tumors and strokes, angiograms can also be used for this purpose. Cerebral angiograms are often ordered after an abnormality has been detected on a CAT scan or MRI.

Before the day of the angiogram, physicians will gather information about the patient's medical history and any medications currently being taken. Individuals should inform their physicians if they are pregnant, trying to become pregnant or nursing prior to the test. In addition, patients should indicate if they have been diagnosed with any of the following:

Preparations for a cerebral angiogram may vary, depending on the status of the patient and the condition being diagnosed or monitored. Patients will be provided with the necessary preparation instructions, which may include:

• Refrain from eating for six to 12 hours prior to testing.
  
  
• Drink eight to 10 glasses of water (not juice or soda) in the 24 hours prior to testing.
  
  
• Make certain medication changes. Physicians may want patients to stop taking certain medications (e.g., aspirin) for a few hours/days prior to testing, or to simply change the dose or timing of the medication. Patients should bring their medications with them to the hospital, whether or not they have suspended that medication temporarily for the test.
  
  
• Undergo blood tests. Certain blood tests may be ordered prior to the procedure, including blood urea nitrogen (BUN), creatine and blood coagulation studies.
  
  
• Arrange for a ride to and from the testing site if it is being done as an outpatient.

On the day of the procedure, the patient will be admitted to the hospital, usually as an outpatient. The patient’s physician (usually a specialized radiologist) and other healthcare professionals will explain the procedure and answer any questions.

The procedure will begin with the physician inserting an intravenous (IV) line into the patient’s arm. The IV allows the physician to give the patient a sedative and other necessary fluids or medications during the procedure.

Most patients will receive a local anesthetic and remain awake for the procedure. However, some patients, especially young children, may be given a general anesthetic and sleep through the procedure. Small devices (electrodes) will be taped to the patient’s body, which allow the physician to monitor heart rate. A small device (pulse oximeter) may be clipped to the patient’s finger to monitor the blood oxygen level during the procedure. The patient’s head will be placed into a positioning device to keep it still during the test.

The catheter can be inserted in the femoral artery of the groin (most common), the carotid artery in the neck (rarely), or the brachial artery of the arm. If the carotid artery is used, sandbags or a towel will be placed under the patient's shoulder to hyperextend the head and neck. If the brachial artery is used, a blood pressure cuff will be placed on the patient’s arm below the insertion site so the dye released from the catheter will not go down into the arm and hand.

The insertion site is cleaned, shaved and numbed (with a local anesthetic). The physician then inserts a thin catheter (using a special needle and wire) into a blood vessel and feeds it through the artery and up into the head. There may be some minor discomfort during this period, but most patients do not feel the catheter moving through the body.

When the catheter reaches the target area, a dye (contrast medium) is injected through the catheter. This dye allows the physician to clearly see the cerebral arteries on the angiogram. The patient may feel hot and flushed for about 10 seconds as the dye is administered. Allergic reactions to contrast dyes are rare. However, patients should inform the physician or testing technician immediately if they experience any of the following sensations during the procedure:

The dye is easily visible to the physician monitoring the angiogram images, which may be viewed on a television monitor or as a series of still images. A series of x-rays will be taken as the physician views the images. A “shadow” cast by the dye will show blockages or irregularities of the arteries. In the case of diseased arteries, for example, arterial walls may appear to be abnormally narrow or irregularly shaped.

Once the angiograms have been taken, the catheter is removed from the body and pressure is placed on the point of catheter entry. In some cases, a small “plug” will be placed in the puncture site to stop the bleeding. This plug will be normally absorbed by the body over time.

The length of the angiogram procedure will depend on which blood vessels are being targeted. The angiogram procedure may take 15 minutes to an hour, or a total of one to two hours from pre-procedural preparation to the removal of the catheter.

Patients are usually monitored in the hospital for a few hours to ensure there is no bleeding at the puncture site or allergic reaction to the dye (contrast medium) used during the angiogram. Some results of the angiogram may be discussed with the patient immediately after the test. Full results may take several days and may be discussed in a follow-up appointment.

Patients are usually released home and put on bed rest for 12 to 24 hours. Patients should gradually return to their normal activity levels. Specific instructions on diet and activity levels will be given to patients prior to release from the hospital.

Patients should continue to drink eight to 10 glasses of water per day for a few days following the angiogram to help flush the remaining dye from their systems. Patients may be advised to keep the area of the puncture or incision (e.g., a leg or arm) straight for six to 12 hours or apply ice to the site after the test. Specific instructions will be provided for care of the puncture site and follow-up appointments.

Although complications from an angiogram are rare, a physician should be notified immediately if patients experience any of the following:

Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctor the following questions related to cerebral angiogram:

1. Why do I need a cerebral angiogram?
   
   
2. What information do you hope to gain from the test?
   
   
3. What are my risks with this test?
   
   
4. How should I prepare for the angiogram?
   
   
5. Do I need to alter my medication usage or diet before the test?
   
   
6. Will the test be an outpatient procedure?
   
   
7. What type of sedation will be used during the angiogram?
   
   
8. When and from whom will I learn the results of the test?
   
   
9. What are my restrictions following the test?
   
   
10. What complications following the test indicate the need for medical attention?
    
    
11. What follow-up tests might be necessary?
    
    
12. What are my options if I am pregnant?