Until 3 years ago, women with symptomatic uterine fibroids-benign tumors within the muscle tissue of the uterus-had limited options for noninvasive treatment. But in 2004, the FDA approved a procedure called MR-guided focused ultrasound (MRgFUS), an outpatient procedure that allows radiologists to target fibroids without damaging the surrounding tissue.

The National Institutes of Health estimates that uterine fibroids occur in nearly 80% of women between the ages of 25 and 50 in the United States. While those who have asymptomatic fibroids do not need to be treated, one in every four women will present with symptoms that include pelvic pain, frequent urination, excessive menstrual bleeding, and infertility. Since MRgFUS received FDA approval, the procedure has offered symptom relief for patients without requiring a hospital stay.

The procedure also allows women to return to their normal quality of life much more quickly than with invasive options, such as hysterectomies, which usually require 2 to 6 weeks of recuperation time.”When I tell patients that they literally can get off my table and go salsa dancing that night, they can’t believe it,” said Suzanne D. LeBlang, MD, radiologist at the University Image Guided Therapy Center, Boca Raton, Fla. “It’s true. I’ve had women play tennis; they can go to work the next day. They are more groggy from the minimal medication we give them to just keep them still during the procedure than from the procedure itself.”

How It Works

MRgFUS combines MR imaging with targeted ultrasound therapy. After carefully studying patient MR images taken in three planes, radiologists plan the ultrasound pathways through the tissue using the ExAblate 2000 MRgFUS system from InSightec, Tirat Carmel, Israel. Currently, the ExAblate 2000 is used exclusively with the GE 1.5T MRI system, although 3T is under investigation.

Patients, who are given a mild sedative to discourage movement, lie awake on their stomachs in the MR imaging machine. Radiologists then use MR thermal imaging to guide ultrasound energy to target the fibroid. Each sonication lasts between 20 and 30 seconds, and the procedure usually takes 3 to 4 hours. Through a process called thermo necrosis, the sonications kill the fibroid tissue, which is then resorbed by the bloodstream.

Focused ultrasound (FUS)

A recent study published in the June issue of Radiology found that women who underwent MRgFUS therapy for uterine fibroids showed significant symptom relief at 3 months and sustained relief at 1 year with no serious side effects. “The side effect that we do encounter during the treatment is mainly menstrual-type cramping, so nothing too severe,” said the study’s lead author, Fiona M. Fennessy, MD, PhD, assistant professor of radiology at Harvard Medical School and staff radiologist at Brigham and Women’s Hospital in Boston. “Because the patients are awake, they just let us know they’re having some cramping, and we give them a little bit more medication.”

The majority of patients respond favorably to the surgery and agree that they would recommend the surgery to a friend. “Most of the patients coming into the trial had very severe symptoms in the 60 or so score range, equivalent to women who are having hysterectomies today,” said the study’s coauthor, Clare M. Tempany, MD, professor of radiology at Harvard Medical School and director of clinical focused ultrasound at Brigham and Women’s Hospital. “Upward of 90% of patients are getting very significant improvement in their symptoms. In general, most of our patients report being back to normal baseline quality of life within 1 to 2 days.”

This return to normalcy is crucial for today’s women, who often balance a career with parenting and cannot afford to be out of commission for long. “For women to take off 2 to 6 weeks affects their jobs and potential income during that time,” LeBlang said. “Stay-at-home moms can’t not lift their children for 2 to 6 weeks or not drive for 2 to 6 weeks. It’s just a tremendous impact on their lifestyle.”

Successful MRgFUS therapy means managing patient expectations throughout the treatment planning and the procedure itself. After each sonication during the procedure, Fennessy asks patients how they feel and to alert her to any discomfort, no matter how mild. “I want to know if they feel any warmth in their skin, which may herald actual heat deposition in the skin where there shouldn’t be; or if they’re having severe cramping; or if they’re having back pain, which may be because too much energy is being deposited on the exiting beam,” she said. “They will let you know what’s going on, and this will prevent any unwanted problems.”

When setting up the ultrasound pathways prior to treatment, radiologists must review the MR images carefully to ensure that no normal tissue will be damaged. “If there’s bowel in the way, that’s a huge problem,” Fennessy said. “Bowel is very sensitive and will actually perforate if it’s in the way.” During treatment, radiologists must be especially vigilant about patient movement, which could alter the pathways. They must also constantly compare the images taken before the treatment to those taken during the procedure to ensure that no changes have occurred. For example, if a catheter malfunctions and the bladder fills, the uterus will likely be impacted. If changes like these occur, the chances of damaging normal tissue are much higher.

117 Sonications, accumulated dose 83.9 cc.

Fibroid volume 107.6 cc, estimated NPV ~85%.

Fibroid volume 39.3 cc, estimated NPV ~90%.   Click on any row of images above for larger version.

Of course, MRgFUS is not for everybody. The FDA has not approved the procedure for women who plan to become pregnant, as the impact on fertility has not yet been determined. It is also contraindicated for patients who are not candidates for an MRI, such as those who wear pacemakers, as well as those who have severe claustrophobia. Patients with extensive scarring on their abdomens may not have the procedure because scar tissue retains heat and can burn.

“If someone has a C-section or some fairly straightforward scar, we can go above or below the scar from one side or the other,” Fennessy said. “So, you can work around a simple scar, but if there is extensive scarring, it makes the pathway too difficult.”

Women who do not qualify for the MRgFUS procedure may be candidates for other treatment options, including hysterectomy or uterine artery embolization, which is a minimally invasive procedure that blocks the blood supply to the fibroids. Patients also may opt for medication to treat symptoms, but this offers only temporary relief.

However, MRgFUS does open up another option for qualified patients who would never entertain invasive surgical options. “There are many women out there with very symptomatic fibroids who are avoiding treatment because they’re afraid of surgery or they don’t want to have a hysterectomy or they don’t want to have a surgical incision,” Tempany said. “That population will definitely want to seek this treatment or alternative minimally invasive treatments.”

What to Consider

In the United States, approximately 20 sites have implemented this procedure, and there are 16 sites in other countries, such as Israel, Germany, and Japan. Both outpatient and hospital facilities considering the integration of this treatment have several factors to weigh before taking the leap. This includes issues such as training the staff to be intimately familiar with the procedure and the equipment, being able to dedicate 3 to 4 hours of their MR imaging resources to each procedure, and having access to a patient and physician population that is willing to consider the treatment option.

LeBlang, who specializes in neuroradiology, found that the procedure was a natural fit for her interests, and she helped launch an outpatient facility called University Image Guided Therapy Center shortly after MRgFUS received FDA approval. “We had a therapy center geared just for using this new technology,” she said.

Second treatment—superior fundal subserosal fibroid targeted—posterior portion difficult to reach due to proximity to spine. 103 Sonications, accumulated dose 88.1 cc, fibroid volume 201.2 cc, estimated NPV ~70%.   Click on either row of images above for larger version.

As with any new procedure, staying current with the literature and getting the required education are crucial. InSightec representatives helped train the radiologists and staff to use the new technology before the first patient came in for treatment, and the representatives sat with the radiologists during the first 10 treatments to provide guidance with the software and hardware. “After the first 10 cases, I was very comfortable on my own,” LeBlang said. “Each case has its subtle differences based on how you approach the fibroid and what kind of parameters you use to treat the fibroid. The more cases you do, the more comfortable you are.”

Introducing a new procedure to the community usually means extensive marketing efforts, and the University Image Guided Therapy Center’s efforts included television and newspaper advertising. But LeBlang found that the most effective method was meeting with local OB/GYNs and other referring physicians. “Sometimes there’s a lag time between new technology and the date of publication,” she said. “It could be a year or two before articles are published in peer-reviewed journals. So, it was important for me to get out there and talk to physicians about the new procedure.”

Referring physicians were a little wary of the new treatment at first, but once LeBlang assured them that her center would work with them to treat each patient and that not every patient qualifies for the procedure, they were much more enthusiastic. “Once they understood that [MRgFUS] wasn’t just replacing all hysterectomies, they were much more comfortable with it,” she said.

Regardless of whether a facility is outpatient or hospital-based, the initial patient screening and assessment are critical, and Tempany said that the assessment should take place in a clinical environment where patients also can have the option to choose other treatment techniques. Once the patient has decided on MRgFUS, radiologists should clearly outline the details and answer any questions.

“On the day before and the day of treatment, it’s important to communicate with your patient very carefully so that she understands what’s going to happen and her expectations of what’s going to happen during the procedure are the same as yours,” Tempany said.

Radiologists must remember to maintain that communication throughout the treatment. “It’s a very interactive procedure; it’s not push a button and then stand back,” Tempany said. “You really need to be talking to the patient all the way through and make sure that she and you have a good rapport that’s established at the beginning.”

What to Expect

As studies continue to explore the effectiveness of MRgFUS treatment for uterine fibroids, clinical trials are already under way to document the benefits of the procedure for other types of tumors. “The experience that we get in helping these women with uterine fibroids is going to catapult the technology into treating other diseases in the body,” LeBlang said.

Already, early trials have been successful in targeting certain types of breast cancers. In the trials, women who plan to undergo surgery for breast cancer also are treated with MRgFUS to test the efficacy of the procedure. “You can prove at pathology that the tumor was treated with focused ultrasound,” Fennessy said. “That’s the first stage.”

There also has been progress in targeting painful bone metastases in patients. “With this technology, there is no radiation, there is no limitation, and it works rapidly,” LeBlang said. “The need for pain control in patients with metastatic bone tumors is dramatically reduced. So the implications for the technology are tremendous.”

Tempany adds that there also has been success with certain types of brain tumors, and future trials will focus on prostate cancer, liver metastases, and renal masses. “It’s going to be really exciting,” she said.

As these trials move forward, advocates for the procedure continue to work with insurance companies to promote coverage for MRgFUS treatment. Although the FDA signed off on the procedure 3 years ago, insurance companies are slower to follow suit. Some of the smaller plans have issued national coverage guidelines, but most of the major players have yet to make a national coverage decision. “What we’re seeing across the country is all plans have been paying on a case-by-case basis,” said Suzanne Ranta, manager of marketing and reimbursement for the Insightec-Americas division based in Dallas.

Currently, sites offering MRgFUS treatment bill for each procedure, and the insurance companies either pay in full or negotiate a rate with the local site.

Communicating the benefits of this procedure is key to influencing insurance companies to cover the treatment. Ranta said that patients themselves have been lobbying their insurance carriers to provide more comprehensive coverage. Physicians also reach out to insurance representatives to promote awareness. “Throughout Texas, [sites are] very aggressively having meetings with insurance companies and medical directors, inviting them to look at procedures so that they can see the value to it,” Ranta said. Through efforts like these, she hopes to see more major coverage for the procedure within the next year.

In the meantime, clinical trials continue to build the case for improved reimbursement. “Evidence-based medicine is essential to prove that this technology is efficacious and that patients really do improve and their symptoms get better,” Tempany said.

Ann H. Carlson is a contributing writer for Medical Imaging. For more information, contact .