What is a cerebral angriogram?
A cerebral angiogram is an x-ray examination of the blood vessels (arteries and veins) of the brain performed by a physician with training in brain imaging. During an angiogram, the patient is generally awake but sedated, having received IV medications to help relax. A nurse trained in conscious sedation monitors the patient during the procedure.
The procedure is accomplished by inserting a thin tube or catheter in the femoral artery (the large artery in the leg) through a small nick in the skin. Under x-ray guidance, the physician then directs the catheter through the arteries leading up to the brain. Once in position, the catheter is used to deliver X-ray dye to the desired location, enabling x-rays of the brain to clearly show the condition of the blood vessels.
In most cases, several injections are needed to provide the desired view of the blood vessels. Once the angiogram is complete, the catheter is removed. To prevent the artery from bleeding, pressure is applied to the catheter insertion site for approximately 15 minutes, or a device may be used to make sure the artery is completely closed. Lasting approximately 1 hour, the procedure may require patients to undergo 2-6 hours of bed rest, dependent upon the methods used to close the vessel.
Why an angiogram?
Cerebral angiography is the most definitive way to view the blood vessels of the brain. In addition to providing high-resolution images, an angiogram also provides information about brain blood flow with each heartbeat.
Brain aneurysms (weak spots in the vessel wall that can burst), vascular malformations (abnormal tangles of blood vessels or vessel constrictions) and vessel blockages (which cause strokes) are among the conditions that can be accurately detected using an angiogram. This procedure, dependent on what it reveals, can also facilitate immediate treatment, which may involve directing medications and/or special devices through the catheter to the problem site to resolve the issue.
What are the benefits and risks of an angiogram?
A cerebral angiogram offers the most detailed depiction of the brain’s blood vessels. Computed Tomography (CT), Magnetic Resonance Imaging (MRI), and ultrasound are often useful for making vascular and other diagnoses. Sometimes, the level of detail available only through catheter cerebral arteriography is necessary for further evaluation, diagnosis, and treatment planning. In certain emergencies, the catheter angiogram combines diagnosis and treatment into a single procedure.
All medical procedures carry some risks. The most serious risk of a cerebral angiogram is stroke. Stroke can result from blood clots that dislodge from blood vessel plaques or from the catheter. Cather-induced tears in the lining of the blood vessels (called “dissections”) can also cause a stroke. In both of these situations, blood flow is restricted depriving brain cells of the vital oxygen they need to survive. Overall, the risk of stroke during diagnostic angiography at high-volume centers is less than 1 percent. Stroke, although uncommon, can result in permanent deficits including inability to move, inability to speak, or vision loss.
More common but less severe complications include bleeding, bruising or infection at the blood vessel puncture site and allergic reactions to x-ray dye or medications used for sedation. There is also some exposure to radiation.
All efforts are made to ensure these risks are minimized during a cerebral angiogram. Some risks may be patient specific and would be discussed prior to performing the procedure.
How do you prepare for an angiogram?
Prior to having an angiogram, your doctor needs to know if you:
• Are pregnant or breast feeding
• Have any allergies, especially to iodine dye
• Have bleeding problems or are on any blood thinners
• Have diabetes, especially if you take metformin
• Have any kidney disease
You will be asked not to ear to drink for several hours prior to the angiogram. You may also be asked to not take specific medications. Blood tests may be performed prior to the procedure.
What is the recovery time after an angiogram?
Since angiograms are usually performed under sedation, you will be asked not to drive or operate machinery until the medicines completely disappear from your system the next day.
It is also important not to perform any heavy lifting for about a week after the procedure to allow the blood vessel puncture site in the leg to heal. Showers are permitted the next day after the procedure; however, you should not submerge the site under water (i.e. no baths or swimming) until the skin nick is completely healed.