Johns Hopkins Study Finds MR-guided Focused Ultrasound Offers Long-term Benefit to Uterine Fibroid Patients


Researcher interview: Hyun S. (Kevin) Kim, MD, Emory University, USA

However, two new challenges quickly arose: gaining widespread physician adoption and insurance reimbursement. Both are needed to build traction against established surgical procedures – such as hysterectomy – and newer less-invasive approaches. Both require the availability of evidence demonstrating long-term patient benefits.

While physician adoption and insurance coverage remain challenges, clinical researchers have begun generating favorable long-term evidence, the most recent of which appears in the August 2011 issue of Academic Radiology.Hyun S. (Kevin) Kim, MD and his former colleagues at Johns Hopkins University (Baltimore, MD, USA) enrolled 40 uterine fibroid patients in their study of ExAblate outcomes and succeeded in tracking 29 of them for three-years, the longest follow-up period published to date.

“Results of this study provide information that people have been waiting for,” explains Kim, who is now an associate professor of Radiology and Surgery at Emory University (Atlanta, GA, USA). “We have shown substantively and effectively that patient outcomes remain positive over the long-term.”

Kim says that results are similar to those reported by long-term studies of uterine artery embolization (UAE), a gold standard of interventional radiology treatments for uterine fibroids.

The team’s findings show that patients experienced sustained symptom relief and quality of life improvements. Data also indicates that 69 percent of patients did not seek alternate treatments during the study period, nor did study participants experience long-term adverse effects or complications.

Kim said that it’s likely that fewer patients would have required alternative treatments if the study was conducted under current FDA guidelines for MR-guided focused ultrasound procedures. Those guidelines allow 100 percent of fibroid tissue to be treated. Instead, the study was launched under the FDA’s initial guidelines, which limited clinicians to treating no more than 33 percent of submucosal fibroids and 50 percent of other types of fibroids.

“Treatments performed in accordance with the FDA’s current, less restrictive guidelines could yield better long-term results than demonstrated by our study,” Kim says. 

Study details

The study’s primary goal was to assess long-term clinical effectiveness, as defined by changes in patient symptoms and scores from quality-of-life questionnaires. Patient follow-up occurred at three, six, 12, 24 and 36 months after treatment. At 36 months, mean scores improved by 47.8 percent for symptom relief and by 39.8 percent for quality of life. Kim said mean symptomology scores indicated significant improvements in every follow-up period.

The study also assessed changes in uterine and fibroid volumes. Measurements were taken before treatment and during follow-up visits. Findings indicate that the most significant volume reductions occurred within six months of treatment. Researchers observed a gradual decline thereafter, yet each follow-up indicated that volume reduction was statistically significant compared to baseline measurements.

The Hopkins team opted not to use the conventional mathematical method of calculating uterine and fibroid volume measurements. Instead, they turned to the leading-edge technology of Bracco’s Dextroscope. The device enabled investigators to create three-dimensional stereoscopic images of the uterus and fibroids. Volume calculations involved adding up the voxels within those images. Kim explains, “We wanted our measurements to be as accurate as possible and had access to the equipment, so it made a lot of sense to use the Dextroscope.”

Kim’s co-investigators were Jun-Hyun Baik, MD, Luu D. Pham, MA and M.A Jacobs, PhD, all of whom are affiliated with Johns Hopkins University School of Medicine.

Written by Ellen C., McKenna