NEW YORK, Feb 16 (Reuters Health) -- Patients with Parkinson's disease,
multiple sclerosis, and other conditions that cause severe tremor -- an
uncontrollable and incapacitating shaking of the arm -- can benefit from the
delivery of electrical pulses to the thalamus, a cluster of nerves deep within
the brain, researchers report.
A new study has found that the treatment, known as thalamic stimulation,
reduces tremor just as well as surgery that destroys the same area of the brain
(thalamotomy), but with fewer complications. Thalamotomy helps between 73% and
93% of patients, but also results in permanent complications in 9% to 41% of the
cases, according to Dr. P. Richard Schuurman from Academic Medical Center in
Amsterdam, the Netherlands, and associates. In thalamic stimulation, an
electrode is implanted into the thalamus and electrical impulses are delivered
to the area from a small pacemaker-like device implanted under the skin,
according to Schuurman and colleagues.
Their report, the first to formally compare surgery with the new
procedure, is published in the February 17th issue of The New England Journal of
Medicine. The study included 45 patients with Parkinson's disease, 10 with
multiple sclerosis, and 13 with tremor from an unknown cause (essential tremor)
who were randomly assigned to undergo one treatment or the other.
Both procedures improved the patient's ability to function daily, although
those receiving thalamic stimulation improved to a greater extent. Patients had
a similar reduction in tremor, with a complete suppression of tremor in 30 out
of 33 in the thalamic stimulation group and 27 out of 34 in the thalamotomy
group.
"Treatment reduced or eliminated tremor more successfully in patients with
Parkinson's disease and in patients with essential tremor than in those with
multiple sclerosis," according to the report.
Six of the 34 patients receiving thalamic stimulation, had complications,
such as difficulty speaking, facial paralysis or balance problems. One patient
died due to problems with implantation of the electrode. In contrast, 16 of 34
patients in the thalamotomy group had such complications, the investigators
note.
Given their experience with the two tremor treatments, the authors
conclude that "thalamic stimulation is preferable to thalamotomy as a means of
improving function with few adverse effects."
"They offer a strong argument for the use of deep-brain stimulation as the
treatment of choice for eligible patients," according to an editorial by Dr.
Gunther Deuschl from Christian Albrechts Universitat in Kiel, Germany.
"But patients so treated must be followed closely at specialized centers,
and the costs of therapy are much higher than those of thalamotomy," he adds.
"Studies of the cost effectiveness of thalamic stimulation are needed."
More research is needed to find even better ways to help patients with
disabling tremors, according to Deuschl.
