Brain Stimulation May Reduce Tremors
Deep Brain Stimulation Offers Lasting Relief From Essential Tremor
Oct. 30, 2003 -- People who suffer from involuntary
trembling caused by a condition called essential tremor may find lasting relief
from deep brain stimulation.
A new study confirms that the procedure safely and effectively
reduces tremors in people who suffer from potentially disabling tremors not
caused by other conditions, such as Parkinson's disease, for more than six
Researchers say it's only the second study to look at the
long-term effectiveness of deep brain stimulation in treating essential tremor
and suggests that the procedure can be safely recommended for people with the
condition that don't respond well to drug therapy.
The procedure involves surgically implanting a device in one or
two areas of the brain that stimulates the brain with electronic pulses. Deep
brain stimulation has also been studied in treating Parkinson's disease and
multiple sclerosis conditions also known to affect movement, but initial
results from a major European study showed the results were slightly better in
people with essential tremor.
Deep Brain Stimulation Provides Long-Term Relief
In this study, European researchers followed 19 people with
disabling essential tremor who did not respond to drug therapy and had a brain
stimulator implanted. The patients were evaluated (both with their device
turned on and off) one year after the procedure and again six years later.
Researchers found that the good results achieved with deep
brain stimulation after one year persisted for more than six years. The
reduction in tremor frequency and severity and improvement in daily living
activities was significant compared with before they had the implant and when
the device was turned off.
Few complications were reported and most were easily
The results of the study appear in the October issue of the
Journal of Neurology, Neurosurgery and Psychiatry.
Essential tremor usually develops during middle age, and
symptoms can remain mild or can increase in severity. Severe tremors can cause
difficulties in performing activities of daily living, particularly activities
that require fine motor skills, like writing. The symptoms do not occur while
the muscle is not active.
Researchers found that a slight increase in brain stimulator
output was necessary to control tremors during the course of follow-up, and
they attribute this increase to the progression of the disease. But they also
acknowledge that it also reflects some tolerance of the therapy.