You may have general anesthesia (asleep and pain-free) and a breathing tube. Or, you may be given medicine to relax you, but you will not be asleep.

A small surgical cut will be made in the groin area or wrist. The doctor will use a needle to create a hole in the femoral artery, a large blood vessel in the groin. It may also be done through the radial artery in the wrist

• A thin, flexible tube called a catheter is passed through the open skin and into the artery.
• Dye is injected through this tube so that the blood vessel can be seen on x-ray images.
• The doctor gently moves the catheter through the blood vessel up to the area being treated.
• Once the catheter is in place, the doctor places small plastic particles, glue, metal coils, foam, or a balloon through it to seal off the faulty blood vessel. (If coils are used, it is called coil embolization.)

This procedure can take several hours.

The procedure is most often used to treat aneurysms in the brain. It can also be used for other medical conditions when open surgery might be risky. The goal of the treatment is to prevent bleeding in the problem area and to reduce the risk that the blood vessel feeding it will break open (rupture).

Your doctor will help you decide whether it is safer to have surgery to block off the aneurysm before it can rupture.

This procedure may be used to treat:

• Arteriovenous malformation (AVM)
• Brain aneurysm
• Carotid artery cavernous fistula (a problem with the large artery in the neck)
• Certain tumors

Risks from the procedure may include:

• Bleeding at the site of the needle puncture
• Bleeding in the brain
• Damage to the artery where the needle is inserted
• Dislodged coil or balloon
• Failure to completely treat the abnormal blood vessel
• Infection
• Stroke
• Symptoms that keep returning
• Death

This procedure is often done on an emergency basis. If it is not an emergency:

• Tell your health care provider what drugs or herbs you are taking, and if you have been drinking a lot of alcohol.
• Ask your provider which medicines you should still take on the day of the surgery.
• Try to stop smoking.
• You will most often be asked not to eat or drink anything for 8 hours before the surgery.
• Take the medicines you have been told to take with a small sip of water.
• Arrive at the hospital on time.

If there was no bleeding before the procedure, you may need to stay in the hospital for 1 to 2 days.

If bleeding occurred, your hospital stay will be longer.

How fast you recover depends on your overall health, the severity of your medical condition, and other factors.

In most cases, endovascular embolization is a successful procedure with good outcomes.

The outlook also depends on any brain damage that occurred from bleeding before, during, or after the surgery.

Treatment - endovascular embolism; Coil embolization; Cerebral aneurysm - endovascular; Coiling - endovascular; Saccular aneurysm - endovascular; Berry aneurysm - endovascular repair; Fusiform aneurysm repair - endovascular; Aneurysm repair - endovascular

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Kellner CP, Erdman JH, Meyers PM. Endovascular management of arteriovenous malformations for cure. In: Winn HR, ed. Youmans and Winn Neurological Surgery. 8th ed. Philadelphia, PA: Elsevier; 2023:chap 454.

Rangel-Castilla L, Shakir HJ, Siddiqui AH. Endovascular therapy for the treatment of cerebrovascular disease. In: Caplan LR, Biller J, Leary MC, et al, eds. Primer on Cerebrovascular Diseases. 2nd ed. Cambridge, MA: Elsevier Academic Press; 2017:chap 149.

Thanh N, Tudor J, Noguerira RG, Zaidat OO. Principles of neuroendovascular therapy. In: Jankovic J, Mazziotta JC, Pomeroy SL, Newman NJ, eds. Bradley and Daroff's Neurology in Clinical Practice. 8th ed. Philadelphia, PA: Elsevier; 2022:chap 54.

Updated by: Deepak Sudheendra, MD, MHCI, RPVI, FSIR, Founder and CEO, 360 Vascular Institute, with an expertise in Vascular Interventional Radiology & Surgical Critical Care, Columbus, OH. Review provided by VeriMed Healthcare Network. Also reviewed by David C. Dugdale, MD, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.