Another study offers more evidence of the potential for deep brain stimulation to relive symptoms of neurological conditions. The study found that the treatment appears to help patients with a difficult-to-treat form of cerebral palsy, researchers writing in The Lancet Neurology report.
The study involved patients with dystonia-choreoathetosis cerebral palsy, a progressively disabling movement disorder that has no effective treatment.
The 13 patients in the study were implanted with deep-brain stimulators to provide a mild electrical current to their brains, in hopes of reducing involuntary movements and tremors.
A team led by Marie Vidailhet of Salpetriere University Hospital in Paris attached electrical leads to the globus pallidus internus (GPi) area of the brain. After a year of continuous neurostimulation, eight out of the 13 people had improvements in motor symptoms.
The results were analyzed using the Burke-Fahn-Marsden dystonia rating scale. The average improvement on the scale was 24.4 per cent, but responses ranged from 21 per cent to 55 per cent in eight patients.
They found no benefit in the patients who had leads positioned outside the boundaries of the GPi.
Two patients had little benefit and three had no benefit or symptoms worsened slightly.
The treatment also reduced disability and pain, and generally, patients felt better. Most patients had fewer symptoms of depression and other mental health problem, but five patients needed treatment with anti-anxiety drugs.
While the results may offer promise for some patients, the team said the study was small and the findings should be interpreted with caution.
Still, they were pleased with their findings and called for further studies to evaluate the effect of deep brain stimulation on other types of cerebral palsy, particularly in children.
The study was partly funded by Medtronic Inc, which manufactures the deep brain stimulators. They are already approved to treat Parkinson's disease, tremors, dystonia and for certain patients with severe obsessive-compulsive disorder.
The company is also studying the devices in patients disabled by stroke.
