Embolization Therapy Overview
What is catheter embolization?
Embolization therapy is a minimally invasive (non-surgical) treatment that occludes or blocks one or more blood vessels or vascular channels of malformations (abnormalities) such as:
- Hypervascularized tumors – abnormal growths of benign(non-cancerous) or malignant (cancerous) tissue which increase in size due to the over-development of blood vessels supplying the area
- Arteriovenous malformations – an abnormal connection between artery and vein that can cause complications
During a catheter embolization procedure, an embolic material (often composed of tiny particles or beads made from a biomedical polymer) is injected into selected vessels to block the blood flow feeding the tumor or malformation, causing it to shrink over time. Embolization is commonly used to treat a number of conditions, including:
- Hepatocellular carcinoma (HCC), liver cancer tumors
- Renal cell carcinoma (RCC), kidney cancer tumors
- Varicose veins
What are the benefits of embolization therapy?
Embolization therapy is carried out by an interventional radiologist and can offer many benefits over traditional surgical treatments, including:
- Minimally invasive
- Highly effective in controlling bleeding
- Reduced trauma
- Faster recover time
- Minimal risk of infection
- No scarring
- No or rare use of general anesthetic
How should I prepare for the procedure?
Before your embolization procedure, you will probably have a sample of blood taken either at the hospital or at a local clinic. Your blood will be tested to check that it clots normally and that there are no problems with your kidneys. At this stage, you should also make sure you tell your doctor about:
- Any medical conditions you have that he/she may not be aware of
- Recent illnesses you have experienced or infections you have been exposed to
- If you are female, any chance you might be pregnant
- Any regular medication you take
Your doctor will also answer any queries you have regarding the procedure and tell you about any special preparations you need to make, such as changes to your medications. You will probably also be asked not to eat or drink anything for several hours before the procedure. When you arrive at the hospital, you will be examined by your interventional radiologist before the procedure begins.
How does embolization work?
The interventional radiologist uses specialist X-ray equipment that allows him/her to see very clear images of your blood vessels on a monitor. The vessels are made more visible by injecting a special liquid, called contrast, which shows up very clearly on the X-ray images. The interventional radiologist inserts a catheter (a long, thin, hollow flexible plastic tube) inside the vessel that leads to the area to be treated. Once the catheter is in the correct location, the embolic material is injected through it until the vessels feeding or making up the malformation are blocked.
How is embolization procedure performed?
The procedure usually takes place in a special room in the hospital called an interventional radiology suite. Sometimes, it is performed in an operating room. In either case, the specialist imaging equipment and monitors will be in the room. Before the procedure, you are placed on the examining table and may be connected to equipment that will monitor your vital signs (pulse, heart rate, blood pressure) during the embolization. Your interventional radiologist may also want to obtain some X-ray images before the procedure starts. A flexible tube called an intravenous (IV) line is inserted into a vein in your arm or your hand. This is used to deliver the drugs which will sedate you during the procedure so that you don’t feel any pain, or you may have a general anesthetic.
The catheter is usually inserted in the groin area and fed through the vessels to the area to be treated. The insertion site will be shaved and sterilized and covered with a drape before a very small cut is made to allow the catheter to be passed into your body. Using the special imaging equipment to view the route through your vessels to the area to be treated, the interventional radiologist advances the catheter to the correct location. One end of the catheter always remains outside the body. The contrast medium is then injected through the catheter and detailed images are taken to give the interventional radiologist a very clear picture of the area to be treated and the position and shape of the vessels feeding the malformation.
The embolic material is then injected through the catheter to the target area. When the interventional radiologist believes the embolization is complete, more contrast medium will be injected and images taken to check the blood flow to the malformation has been effectively blocked. The catheter is removed and pressure is applied to the catheter entry site to stop it bleeding before a small dressing is applied. It is such a small cut that it does not require any stitches. Your intravenous line will be removed, but the site where it was connected in your hand or arm may be left accessible with a short tube in case it is required for medication during your recovery.
You will be moved from the suite or operating room to a recovery area, where your vital signs will continue to be monitored.
What will I experience after the procedure?
The most common side-effect of embolization is a condition called ‘post-embolization syndrome’ or PES. Patients may feel nauseous and most feel some degree of pain in the area that has been embolized. These symptoms are very normal and can be managed by medication which will be given to you orally (by mouth) or intravenously (through an IV line into your hand or arm). Your doctor will want to make sure you are comfortable before you leave the hospital. Most patients feel well enough to go home within 24 hours of the procedure and are able to resume their normal day-to-day activities within 7-10 days.