DEEP BRAIN STIMULATION SHOWS PROMISING RESULTS FOR SOME PATIENTS WITH CEREBRAL PALSY
Deep brain stimulation improves movement skills and quality of life in some patients with a subtype of cerebral palsy (CP) (dystonia-choreoathetosis CP)*, and could be an effective treatment option for these patients, finds an Article published Online first and in the July edition of The Lancet Neurology.
Cerebral palsy with dystonia-choreoathetosis is a common and progressively disabling disorder in children and adults for which no effective treatment exists. Bilateral pallidal deep brain stimulation (BP-DBS) is a surgical procedure which involves the implantation of electrodes to stimulate parts of the brain in order to reduce involuntary movements and tremors, and has been shown to be an effective treatment for primary generalised dystonia. However, the effect of this treatment on a secondary dystonia such as dystonia-choreoathetosis, which shares most of the features of primary dystonia, is not clear.
To investigate the effectiveness of BP-DBS on movement skills, functional disability, and quality of life, Marie Vidailhet and colleagues implanted leads in the globus pallidus internus (GPi) area of the brain of 13 patients with dystonia-choreoathetosis CP. All patients were evaluated for changes in the severity of dystonia-choreoathetosis using the Burke-Fahn-Marsden dystonia rating scale before surgery and again after 12 months of continuous neurostimulation. Quality of life, cognitive function, and mood were also assessed.
Findings showed that after 1 year, in most cases BP-DBS resulted in sustained improvement in motor symptoms in most areas of the body (neck, trunk and limbs). The average improvement in the Burke-Fahn-Marsden dystonia rating scale movement score was 24.4% after 1 year. However, the response was varied with improvement between 21% and 55% in eight of the patients, two patients showing little benefit, and three having no benefit or deteriorating slightly.
Importantly, functional disability, pain, mental health-related quality of life, and social interaction seemed to improve and there was no worsening of cognition or mood.
The authors report that one factor that might be key to a good outcome in patients is the optimal placement of leads in the GPi area of the brain, with no beneficial affect shown in patients with leads positioned outside the boundaries of the GPi.
They say that despite the promising findings the study only involved a small number of patients and should be interpreted with caution. They call for further studies to evaluate the effect of DBS on more complex and common types of CP, particularly in children.