The treatment of neurologic disease took a major step forward this past week with the publication of a clinical trial that used ultrasound waves to treat Essential Tremor. Essential tremor affects about 10 million people in the USA and can be extremely disabling. For patients that fail medical therapy invasive surgical options are considered, including deep brain stimulation (DBS). DBS surgeries involve drilling a hole in the skull and implanting an electrode into structures deep in the brain to turn off the unwanted signals that cause the tremor.
A study of 15 patients lead by Dr. Jeff Elias (University of Virginia) was published in the New England Journal of Medicine this week and describes how researchers used ultrasound waves to effectively treat Essential Tremor non-invasively – no cutting or drilling. Briefly, a helmet like device sends over one thousand ultrasound waves through the skull and focuses the ultrasound energy onto a tiny point deep in the brain. The principle is similar to using a magnifying glass to focus the sun’s rays to burn a hole in a leaf. Each beam has no effect on healthy tissue but there is a dramatic effect at the point of beam convergence. Using an MRI machine, researchers were able to visualize a small target area and create a lesion in the brain at a precise target with extreme accuracy. Patients are awake and interactive throughout the procedure, and feedback from the patient helps guide treatment.
At one year follow-up all patients had significant improvements in their quality of life and tremors. Four patients had tremor so severe they were unable to feed themselves, however they can now feed themselves independently after the procedure.
MR guided Focused Ultrasound technology offers the potential to non-invasively treat many other neurological conditions including Parkinson’s Disease, brain tumors, epilepsy, stroke, OCD, trigeminal neuralgia, and difficult to treat chronic pain from cancer and other causes. Clinical trials for Essential tremor, Parkinson’s disease, and brain tumors have already begun.
Swedish Neuroscience Institute continues to be a leader in the adoption of minimally invasive therapies to treat neurological disease. The Institute has partnered with InSightec, the manufacturer of the ExAblate Transcranial Neuro device, and with the Focused Ultrasound Foundation, which provides support for clinical trials as well as facilitating collaborative research. Clinical trials using focused ultrasound for essential tremor at Swedish have recently opened for patient enrollment. I was part of the essential tremor treatment team at the University of Virginia and recently joined the Swedish Neuroscience Institute to partner with Dr. Ryder Gwinn (Principal Investigator) for the essential tremor trial.