Focused Ultrasound Shows Safety and Feasibility in Epilepsy Pilot Trial

A pilot clinical trial has shown that focused ultrasound neuromodulation — a noninvasive technique that uses sound waves to stimulate targeted brain regions — is safe and feasible for people with drug-resistant epilepsy, which does not respond to medication. The results, published in the journal Epilepsia, were led by Hsiang-Yu Yu, MD, a neurologist at Taipei Veterans General Hospital in Taiwan, and build on the group's earlier study with six participants.

The trial enrolled 12 adults between January 2022 and March 2024. Each received low-intensity focused ultrasound (LIFU) delivered through the NaviFUS device, which uses neuronavigation to guide the ultrasound beam. The brain target was personalized to each participant's seizure onset zone — the area where seizures begin — identified through clinical examination, MRI, positron emission tomography (PET) and electroencephalographic (EEG) testing, among other methods.

The study used a randomized, sham-controlled crossover design: some participants initially received a sham treatment that matched the real procedure in setup and duration but delivered no ultrasound energy, while prerecorded background sounds simulated the treatment noise. Participants in the sham group could later cross over to receive the actual LIFU treatment, after which the follow-up period was extended to further monitor seizure outcomes.

During each LIFU session, participants underwent three consecutive 5-minute sonications separated by two 5-minute rest periods, using an intensity of 0.3 watts per square centimeter (mechanical index of 0.25), corresponding to a peak pressure of 0.18 megapascals.

The researchers concluded that the procedure accurately targeted each participant's seizure onset zone and that LIFU neuromodulation with the NaviFUS device was safe and well tolerated, with no serious adverse events or tissue damage. The primary crossover analysis did not find a statistically significant antiseizure effect, and the authors said further studies are needed to confirm efficacy and optimize treatment parameters. “This study represents an important step in the clinical translation of focused ultrasound for epilepsy,” said Arthur Lung, PhD, chairman of NaviFUS.