The U.S. Food and Drug Administration (FDA) has approved the first MR-guided focused ultrasound device to treat essential tremor in patients who do do not respond to treatment with medication. The ExAblate Neuro from InSightec (Haifa, Israel) is the first system in the United States to receive FDA clearance for use in a brain indication. It uses focused ultrasound waves to precisely target and ablate tissue within the brain.
Essential tremor is the most common movement disorder in the world. In the United States alone, an estimated five million people experience uncontrollable tremors of the hand, head, arms, voice, legs or torso.
The FDA approval was based on data from a multicenter double-blind control clinical trial supported by the Focused Ultrasound Foundation, the BIRD (Israel-US Binational Industrial R&D) Foundation, and Insightec. Principal investigator W. Jeffrey Elias, MD, professor of neurological surgery at the University of Virginia Health Sciences Center in Charlottesville, and peers at seven other academic medical centers treated 76 patients unresponsive to treatment with essential tremor. The patients treated with the ExAblate Neuro achieved a nearly 50% improvement in their tremors and motor function 90 days following treatment compared to their baseline scores. The patients retained a 40% improvement after one year.
In the randomized clinical trial, 56 patients received the ExAblate Neuro treatment and 20 received a placebo treatment. Patients in the placebo control group were able to cross over into the treatment group three months later.
The FDA reported that adverse events were consistent with those reported for thalamotomy surgery, including numbness and tingling of the fingers, headache, imbalance and/or unsteadiness, ataxia, or gait disturbance. The treatment is inappropriate for pregnant women, patients with advanced kidney disease or on dialysis, with unstable heart conditions, or with a history of abnormal bleeding.
The Focused Ultrasound Foundation is engaged in additional brain research, including Parkinson’s disease, epilepsy, brain tumors, dystonia and Alzeheimer’s disease. Chairman Neal F. Kassell, MD, stated in a press release that the foundation is supporting research that uses focused ultrasound not only to destroy tissue, but to stimulate the immune system and open the blood brain barrier to delivery drugs. The foundation is also supporting a variety of technical projects to make brain treatment safer, faster, and more effective.
FDA approves use of MR-guided focused ultrasound device to treat essential tremor. Appl Radiol.