Hysterectomies are one of the most performed surgeries in Canada, but many doctors say the surgery is performed too often, particularly in patients with uterine fibroids.

Now, researchers in Toronto are testing a therapy that "burns away" the fibroids' blood supply, without the need for surgery.

Uterine fibroids affect thousands of Canadian women, causing growths in the uterus that can range in size from microscopic to large masses that swell the uterus.

Most women with fibroids have no symptoms, but those with larger growths can experience excessive, prolonged menstrual bleeding, bloating and pelvic pain. The usual treatment has been a hysterectomy, which completely removes the uterus.

Now, researchers at Sunnybrook Health Sciences Centre are testing an experimental treatment called MRI-guided focused ultrasound therapy. They say the treatment can eliminate certain kinds of fibroids in less than two hours, with no surgery at all.

During the focused ultrasound therapy, the patient lies on a table and is guided into an MRI unit. The MRI locates the fibroids and then ultrasound waves are directed at them to heat them up over 60 degrees Celsius, painlessly burning away the fibroid's blood vessels.

The procedure doesn't eliminate the fibroids but most do shrink by 20 to 50 per cent. Even in fibroids that don't shrink much, many women report less monthly bleeding, with up to 90 per cent of women reporting they are symptom-free soon after.

"They say it's transformed their ability to function," says Sunnybrook radiologist Dr. Elizabeth David. "Their lives really are transformed when they don't have to worry about this issue."

David says she's been "extremely happy" with how well the procedure has worked on the patients she's studied, noting that focused ultrasound would be "just an additional tool" to offer women with fibroids..

Hysterectomy is the most effective treatment for fibroids, but it's a major abdominal surgery that carries the risk of complications, involves a long recovery, and is costly to the health care system.

Doctors can also recommend myomectomy, a less invasive surgery in which parts of the fibroids are removed but the uterus is left in place. But the fibroids can return in as many as half of patients who receive that procedure.

Health Quality Ontario (HQO) is recommending the widespread use of focused ultrasound, saying it will save millions of dollars by keeping many women out of surgery

"Our experts concluded that this is an effective intervention," says Dr. Irfan Dhalla, the vice-president of evidence development and standards at Health Quality Ontario. "It does work the vast majority of the time. The recurrence rate is low and it's a good option for women who do not want to have their uterus removed."

The HQO report has now been submitted to the Ontario government, which is currently reviewing it to decide if it will allow more MRI-guided ultrasound units to be set up, to give more women the choice of a treatment without surgery.

With a report from CTV medical specialist Avis Favaro and producer Elizabeth St. Philip