Focused ultrasound surgery (FUS) is a noninvasive treatment option for uterine fibroids — noncancerous growths of the uterus.

Also called magnetic resonance-guided focused ultrasound surgery or focused ultrasound ablation, this treatment happens while you're inside an MRI scanner equipped with a high-energy ultrasound transducer.

The MRI scans give your doctor the precise location of a uterine fibroid and the locations of nearby structures to be avoided, such as the bowel and bladder. While the MRI monitors the targeted fibroid and surrounding structures, the ultrasound transducer delivers focused sound waves into the fibroid. The sound waves heat and destroy small areas of fibroid tissue until most or all of the fibroid is destroyed.

Focused ultrasound surgery isn't widely available, but is done at specialized clinics.

Focused ultrasound surgery:

• Eases bothersome symptoms associated with uterine fibroids, including heavy menstrual bleeding and pelvic pain and pressure
• Provides a noninvasive alternative to surgical treatment of fibroids
• Typically allows a rapid return to normal activities after the procedure

Although focused ultrasound surgery offers many advantages over other fibroid treatment options, it's not the best option for everyone. It may not be a good choice for you if:

• You have multiple abdominal scars that make it difficult to find a safe path between the transducer and the fibroid
• You have many fibroids or very large fibroids
• Your doctor suspects your fibroid-like growth might be a cancerous growth instead

Focused ultrasound may be an option for women who still want to have children. A number of women have had successful pregnancies after treatment, and the treatment appears to be safe. However, more study is needed on the possible long-term effects on a woman's ability to have a successful pregnancy.

Rarely, focused ultrasound surgery results in:

• Burns to the skin on your abdomen
• Damage to tissues and structures near the fibroid targeted for treatment
• Nerve damage causing temporary back or leg pain after the procedure
• Blood clots in your legs (deep vein thrombosis)

Other drawbacks specific to focused ultrasound surgery include:

• Less long-term data on safety and effectiveness than most other fibroid treatments
• Less data on fertility and pregnancy than with other fibroid treatments

It's possible that focused ultrasound won't be able to treat all of your fibroids. In addition, you may need further treatment if your symptoms return.

To determine whether you're a good candidate for focused ultrasound surgery, your doctor may perform a pelvic MRI scan before treatment. Your doctor will also need to administer a pregnancy test prior to the procedure.

Clothing and personal items

An MRI uses a magnetic field to create detailed pictures of the inside of your body. Metal objects on — or in — your body may interfere with the magnetic field. This can affect the quality of the MRI, may damage electronic items and can possibly cause a safety problem.

If possible, leave jewelry or metal or electronic accessories at home, as you'll be asked to leave these items in the dressing room before the procedure.

Tell the technologist if you have any metal or electronic devices inside your body, such as metallic joint prostheses, artificial heart valves, implanted electronic devices, cochlear implants or body piercings.

Other precautions

The day of treatment you'll need to shave your lower abdomen between your pubic bone and bellybutton.

Before the procedure

Focused ultrasound surgery is performed as an outpatient procedure in an MRI scanning room. You may be asked to fast for hours before the procedure.

Shortly before the procedure begins, you'll have:

• An intravenous line placed in one of your veins to inject contrast material for MRI and to give you medication for relaxation and pain
• Special stockings to prevent blood clots put on your legs
• A urinary catheter inserted into your bladder to keep the bladder stable during your treatment and improve visibility of the uterus

During your treatment, MRI allows doctors to evaluate the effects and define areas that need additional treatment.

During the procedure

Treatment time varies, depending on the size and number of fibroids you have, though you can expect it to take around three hours. Here's what happens during the procedure:

• You'll lie on your stomach on a movable table that slides into the opening of the MRI scanner. A doctor will monitor you from an adjoining room and can talk to you and hear you by microphone.
• Using focused ultrasound waves (sonications), each portion of the fibroid is heated. MRI is used to monitor tissue temperature and determine if the fibroid has been heated enough to achieve the desired results. The process is repeated until most of the fibroid has reached a temperature that should destroy the tissue.
• Each sonication lasts approximately 12 to 30 seconds, and then there is a 45- to 90-second rest period to let the tissue cool down. It usually takes 50 or more sonications during a treatment session to destroy a fibroid. However, depending on the size and number of fibroids you have, more sonications or a second treatment may be necessary.
• Throughout the treatment, you'll be asked about your level of discomfort so that your medication can be adjusted or other necessary changes can be made.

After the procedure

You'll need a friend or family member to drive you to and from your treatment, and to stay with you at least five hours after the procedure due to the medications you receive during treatment.

You can usually resume your normal daily activities within a day of the procedure. Over-the-counter pain-relieving drugs, such as ibuprofen or acetaminophen, can be used to treat any discomfort.

It takes months, and sometimes even years, for your body to gradually absorb the treated tissue. But most women notice significant improvement in their fibroid-related symptoms within the first few months after focused ultrasound surgery.

If fibroids return, you may need a second procedure to treat them. The need for repeated treatment may be more common in women who've had focused ultrasound compared with other fibroid treatments, such as uterine artery embolization.