A cerebral angiogram (also known as an arteriogram) for the brain is a diagnostic procedure just like the coronary angiogram done for the heart vessels, that provides images of the blood vessels in the brain and/or head. The test is performed to find blocked or leaking blood vessels. This test can help to diagnose such conditions as the presence of a blood clot, fatty plaque that increases the patient’s risk of stroke, cerebral aneurysm or other vascular malformations.
A cerebral angiogram requires that a special dye be injected into the arteries of the head or brain. Under the direction of an expert physician, this procedure is done by inserting a thin tube (a catheter) through a blood vessel, (most often starting in the patients thigh) all the way up to the head and/or brain. When the catheter is in the correct position the dye is them injected. At this point the cerebral angiogram can generate the images of the blood vessels.
Cerebral angiography is most frequently used to identify or confirm problems with the blood vessels in the brain.
Your doctor may order this test if you have symptoms or signs of:
- Abnormal blood vessels (vascular malformation)
- Narrowing of the arteries in the brain
It is sometimes used to:
- Confirm a brain tumor
- Evaluate the arteries of the head and neck before surgery
- Find a clot that may have caused a stroke
In some cases, this procedure may be used to get more detailed information after something abnormal has been detected by an MRI or CT scan of the head.
This test may also be done in preparation for medical treatment (interventional radiology procedures) by way of certain blood vessels.
As with any diagnostic procedure, patients preparing for a cerebral angiogram must observe simple pre-test instructions. These include:
- Make arrangements for transportation home following the procedure. Patients are not permitted to drive after a cerebral angiogram.
- Do not eat or drink after midnight the night before the test.
- Patients who take medications routinely should check with their physician. If routine medication is allowed the day of the test, it should only be taken with a small sip of water.
- Leave all valuables at home.
- Inform the angiogram technician if pregnant or breast-feeding. Also inform the technician of any of the following conditions: asthma, diabetes, and allergies to iodine, shellfish, drugs, or latex.
Prior to the angiogram, patients are asked to change into a hospital gown. It is not unusual for blood and urine samples to be collected or an electrocardiogram (EKG) or chest x-ray to be performed. In the nursing unit, a mild sedative and fluids are administered through an IV. Medication is available for pain and anxiety.
In the procedure room, the patient is positioned on an x-ray table. A blood pressure cuff, heart monitor, and pulse oximeter are placed on the patient to monitor their vital signs. A sterile drape is placed over most of the patient’s body. The patient’s head is secured to the table with straps to keep it still.
The area where the catheter (small tube) will be inserted is washed and a local anesthetic is given to prevent pain. The catheter is usually inserted into an artery in the groin, but an artery in the thigh, neck, or arm may be used instead. A tiny incision is made into the artery and a guide wire is inserted and carefully fed through the artery. The catheter tube is slid over the guide wire into the artery. Using fluoroscopy (an advanced imaging tool), the physician is able to watch the catheter as it is maneuvered into the blood vessels of the brain. When the catheter is correctly positioned, the contrast dye is injected. More than one injection of dye may be necessary to complete the evaluation.
During the injection of the contrast dye, some patients report a flushed warm feeling, nausea, or get a salt or metallic taste in their mouth. This is normal and should be reported to the physician. When the x-rays are taken, the patient is given special instructions for breathing and swallowing. The patient may be asked to do simple movements or speak during the test.
When the test is finished, the catheter is removed and pressure is applied to the incision for 15-20 minutes to stop bleeding. When the bleeding stops, a thick dressing is placed on the incision. The patient is then moved to an observation area.
While the patient is in the observation area, nurses check vital signs, the incision site, and attend to all of the patient’s needs. It is necessary for the patient to lie still with his or her head flat for six to eight hours. Gradually the patient is allowed to get out of bed with assistance; lightheadedness and dizziness may occur if the patient gets out of bed too quickly.
When the patient is released home, he or she is given discharge instructions. These ‘at home’ instructions include:
- No heavy lifting, exercise, and driving for 48 hours. Do not operate machinery for at least 24 hours. It is important not to stress the incision/puncture site.
- During the next 24 hours, drink plenty of fluids to flush the contrast dye from the kidneys. Avoid beverages that dehydrate the body, such as alcohol or coffee.
- Resume a regular diet.
- There is bleeding, bruising, redness, warmth, or loss of feeling at the incision site.
- Numbness, tingling or weakness occurs in the extremities (arms, legs) or face.
- Urination is difficult.
- A change or loss of vision occurs.
- Swallowing or talking is difficult.
- Mental confusion or comprehension difficulties occur.
- An allergic reaction develops, such as hives, itching, rapid heart beats, dizziness, chest pain, or shortness of breath.
The chance of any complication with a cerebral angiogram is small. However, it is important to be aware of the possible risks, which include internal bleeding, damage to a blood vessel, infection, allergic reaction to the contrast dye, and stroke. Of course your physician will be carefully monitoring for any complications and is fully trained to respond if one arises.