Embolization procedures stop blood flow to a specific blood vessel. Treatment works by placing a substance in the vessel to prevent blood from flowing through it. You may need this procedure if you have excessive bleeding, a vascular malformation or a tumor.


What is an embolization procedure?

Embolization is a minimally invasive procedure that blocks or closes a specific blood vessel. It’s often a planned (elective) procedure. Some cases are emergencies and must be performed right away.


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How can embolization help me?

Embolization offers temporary or permanent relief for a variety of conditions by:

  • Eliminating atypical connections between blood vessels.
  • Closing off blood vessels that feed tumors and other abnormal growths.
  • Stopping or preventing excessive bleeding.

What conditions does embolization treat?

Embolization may be used for conditions affecting nearly every area of your body. The procedure can help you if you have:


How does an embolization procedure work?

Embolization uses tiny particles or objects called embolic agents to halt blood flow. Your healthcare provider delivers the agents using long, thin tubes (catheters). The catheter is inserted through a puncture in your skin and follows the path of the blood vessel to reach the treatment area. Instruments at the catheter tip make it possible to carry out the procedure.

Who performs embolization procedures?

An interventional radiologist performs this type of procedure. This medical specialist uses real-time imaging and catheters to navigate your body’s blood vessels and deliver tests and treatments.


Procedure Details

What happens before an embolization procedure?

Healthcare providers perform imaging studies to assess blood flow and vessels near the treatment area. You may need an ultrasound, CT scan or MRI. You may also need to stop taking certain medications, such as blood thinners.

What types of embolic agents are used?

The agent used depends on your medical needs and the type of blood vessel being treated.

Embolic agent types include:

  • Balloons: Tiny balloons deployed in a blood vessel to temporarily or permanently block it.
  • Gelatin foam: Sponge-like material made of gelatin that dissolves after a few days.
  • Liquid glue: Adhesive substance that hardens quickly to seal abnormal vessels.
  • Liquid sclerosing agents: Substances, including alcohol, that destroy tissue on contact. This causes abnormal blood vessels to close.
  • Metallic coils: Tiny devices made of stainless steel and platinum that can be placed in a precise location.
  • Particulate agents: Substances, including spheres of various sizes, that permanently block small vessels.

What happens during embolization?

Here’s what happens during an embolization procedure:

  1. You receive mild sedation to help you relax. Your provider will inject additional medications into the puncture site to numb it.
  2. The interventional radiologist makes a small puncture in your skin near your wrist, groin or neck.
  3. They slide a catheter through the puncture and advance it to the treatment area.
  4. Imaging technologies, such as fluoroscopy, enable the interventional radiologist to view the treatment area and instruments.
  5. Your provider injects a special dye through the catheter for enhanced views of your blood vessel and blood flow.
  6. The interventional radiologist delivers the embolic agent and checks to ensure blood flow to the area has stopped.
  7. When the embolization procedure is complete, the interventional radiologist removes the catheter. They cover the incision with a bandage. No stitches or large incisions are necessary.

What are the different embolization techniques?

There are many types of embolization. They include:

  • Chemoembolization or radioembolization, which implants embolic agents and high-dose chemotherapy or radiation therapy into blood vessels feeding a tumor. It’s for cancers that start in or spread to your liver.
  • Sac packing is a method of treating aneurysms by packing multiple coils into a treatment area.
  • Sandwich technique completely removes the affected area from circulation. It involves placing embolic agents before and after the location of the abnormal tissue.
  • Stent-assisted coiling for aneurysms prevents the embolic agent from moving away from its intended location (migrating). It uses a hollow mesh tube to hold the embolic agent in place.
  • Particle embolization decreases or eliminates blood flow to benign tumors.

What does an embolization procedure feel like?

Due to sedation and numbing medications, you won’t feel discomfort during the procedure. There may be a slight pinch from the needle poke that delivers the numbing agent. You may also feel pressure as your provider inserts the catheter and a warm sensation from the contrast dye.

How many procedures will I need?

For many conditions, one embolization procedure is all you’ll need. If you have a large venous malformation, healthcare providers may use a staged approach. This might include one or more treatments every few weeks.

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Risks / Benefits

What are the benefits of embolization?

Embolization offers many benefits.

  • This procedure quickly controls abnormal bleeding and has a high success rate.
  • It’s gentler on your body than open surgery. Instead of an incision, there’s a small puncture that causes minimal blood loss.
  • Most people resume daily activities within a week.

What are the risks of an embolization procedure?

Embolization carries many risks. Your likelihood of experiencing them depends on the location of the procedure and type of embolic agent. Potential risks include:

  • Air embolism, when an air bubble blocks a blood vessel.
  • Allergic reaction to contrast dye.
  • Bruising or bleeding at the puncture site.
  • Embolic agent misplacement or migration.
  • Infections, including sepsis, which can be life-threatening.
  • Nerve damage (neuropathy).
  • Soft tissue necrosis, especially when more than one vessel is embolized.
  • Stroke or blindness if embolic agents in the head migrate.

Recovery and Outlook

What will I feel like after an embolization procedure?

Most people experience pain at the puncture site. This typically lasts a few days. Some people experience post-embolization syndrome, which includes fever, nausea and vomiting. It can happen with any embolization procedure, but is more common with uterine artery embolization.

Additional side effects depend on the location of the procedure:

  • Head or brain: Intracranial malformation embolization for blood vessels in your head may cause a mild headache.
  • Uterus: Uterine artery embolization may cause cramping.

What can I expect during recovery?

Most people need to stay in the hospital for at least one night. During this time, you receive pain medications to help you stay comfortable.

What can I expect once I return home?

You’ll need to rest and limit physical activity for a few days. Depending on the puncture site, you may need to avoid certain everyday activities:

  • Groin puncture: Try to avoid going up or down stairs.
  • Wrist puncture: Avoid repetitive motions, like writing or typing.

You’ll also need to avoid strenuous physical activity like lifting heavy objects. Short daily walks can prevent complications like constipation from sedatives and blood clots. You’ll also need to take care of the puncture wound by icing it to relieve swelling and keeping it clean.

When To Call the Doctor

When should I contact my healthcare provider after having an embolization procedure?

Call your healthcare provider if you experience:

  • Blood clot symptoms, which include redness or swelling in your groin.
  • Difficulty breathing.
  • Excessive bleeding.
  • Nausea and vomiting that make it difficult to keep food or fluids down.
  • Painful or fast-growing lump near the puncture site.
  • Signs of infections, such as fever or warmth near the treatment area.

A note from Cleveland Clinic

Embolization procedures stop blood flow to a specific vessel. It treats conditions such as AVMs, frequent nosebleeds, traumatic injuries and certain cancers. As a minimally invasive procedure, embolization is gentler on your body than surgery. Most people experience less pain during recovery and get back to their daily activities quickly.

Medically Reviewed

Last reviewed on 07/14/2022.

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