Research Snapshot: Drs. Joshua Wong & Leonardo Almeida

By Todd Taylor

graph of conventional pulse vs. active biphasic pulse
This figure highlights the waveform differences between conventional clinical DBS and active recharge biphasic DBS that were both evaluated in this study.

New research conducted at the University of Florida showed that a form of deep brain stimulation called biphasic DBS was safe, well tolerated and may provide faster improvement of symptoms in patients with primary dystonia.

The 10-participant pilot study, led by Joshua Wong, M.D., an assistant professor of neurology, and Leonardo Almeida, M.D., an associate professor of neurology at the University of Minnesota and a former assistant professor of neurology at UF, was recently published in the journal Parkinsonism and Related Disorders.

Unlike conventional DBS settings, active recharge biphasic DBS delivers two symmetric square wave pulses sequentially without delay between pulses.

“Dystonia can be very difficult to treat, and it can sometimes take months for patients to see the benefit from DBS. Our preliminary findings show that biphasic DBS may be able to provide benefit faster than traditional DBS,” Wong said.

In the double-blind, nonrandomized, single-center study, 10 participants with primary dystonia spent one day on traditional DBS settings and one day on biphasic DBS settings. The research team found that biphasic DBS was safe and well tolerated, and used special research software to compare the severity of dystonia symptoms, such as involuntary muscle contractions and twisting movements, between the two days. Using the Unified Dystonia Rating Scale and video recording, the researchers concluded that biphasic DBS shortened the time to improvement of symptoms in the participants.

We hope to conduct a larger and longer study of biphasic DBS, hopefully including a scenario where we can let people stay on biphasic DBS for days to weeks at a time to see the long-term benefits of this technology,” Wong said.

Researchers will also examine whether the immediate improvement revealed by the study persists over time and whether similar levels of improvement are achieved with conventional DBS.

Read the paper in Parkinsonism and Related Disorders.