Three new papers, published in the November issue of Ultrasound in Obstetrics and Gynecology support the use of InSightec's (Haifa, Israel) ExAblate Magnetic Resonance-guided Focused Ultrasound (MRgFUS) system for the treatment of Uterine Fibroids.

According to the company, one study demonstrated that non-invasive treatment with the device offers women a significantly less risky treatment for symptomatic uterine fibroids with much faster recovery time than hysterectomy. Another study reveals improvement in outcomes of ExAblate treatments as physicians improved their skills with the system. Finally a third study shows the positive correlation in the volume reduction of the fibroid to symptom improvement after two years.

The device, which received initial FDA clearance in 2004, gives the ability for the physician to use the Magnetic Resonance Imaging to visualize a patient's anatomy and then aims the focused ultrasound waves at the targeted tissue to destroy it. The MRI component of the application allows the physician to monitor and continuously adjust the treatment in real time. The patient is consciously sedated to reduce pain and minimize motion.

The MRgFUS system keeps track of all regions that have reached the thermal dose threshold during ablation. Once the entire tumor has been ablated, the patient is given contrast agent and post-contrast MR images are used to evaluate the non-perfused volume, the company said.

"We now know that MRgFUS works quickly with very few side effects and that patients can return to normal function almost immediately after treatment," Arthur Chan, PhD director of clinical marketing & professional education for InSightec told Medical Device Daily.

"We also know that the larger the area of ablation that can be produced in the targeted fibroids, the better the symptomatic response and the less the need for other fibroid interventions, and that when the early symptomatic response is highly effective, long-term improvement of symptoms is almost invariably seen."

The first published paper details prospective study of 192 patients at 14 different medical centers across the U.S., Israel, the UK and Germany, showed that MRgFUS was associated with significantly fewer adverse events in comparison with hysterectomy patients.

"The first paper describes the safety results of our side by side study vs hysterectomy and the quick return to normal activities and work, with an average of only 1 day away from work as opposed to 6 weeks for hysterectomy," Chan said.

The second paper which details results from a retrospective multi-center study of patients who had undergone MRgFUS in Japan, researchers found that as practitioners gained more experience using MRgFUS, their treatments were increasingly effective and that the percentage of patients that who required a second treatment at one year decreased significantly, from 12% in the first group to 5% in the patients treated later. These numbers are similar to the retreatment rates of other uterine-conserving solutions.

Finally, the last paper which is based on research done at Shinsuma Hospital, demonstrated that different types of fibroids respond differently to MRgFUS. Low-intensity T2 signal fibroids respond extremely well, with large areas of destruction being easily produced which lead to large Non-Perfused Volumes (NPVs).

Chan said that in comparison, fibroids of high intensity T2 signal do not respond as well to MRgFUS. As a result, at 12 months only 2.9% of the patients treated with low intensity fibroids required retreatment and 14% at 24 months, compared to 22% at 24 months for high intensity group.

"Anytime we have new published data, it creates awareness and provides education to both the physicians and patients," Chan said. "We believe that patient advocacy efforts and physician training and outreach are two key components in ensuring that this procedure is provided as a viable option for women suffering from fibroids."

The published papers could also give the company more ammunition with future plans for expanding the use of the ExAblate.

Chan said that the company was working on a more advanced version of the device, the ExAblate 4000 and that it would be a platform focusing on a variety of transcranial indications, such as "brain tumors, functional neurosurgery, stroke and targeted drug delivery."

"InSightec is constantly designing and developing new technology based on feedback obtained from its clinical users," Chan told MDD. "We believe that our technology holds the key to the future of surgery and cancer treatment: a non-invasive, incisionless, one-time outpatient procedure using non-ionizing ultrasound."

Omar Ford, 404-262-5546;
omar.ford@ahcmedia.com