Chronic electrical stimulation of the globus pallidus for treatment of Parkinson's disease

Abstract We report the effect of pallidal stimulation for the patients with Parkinson's disease (PD) and the changes of neurotransmitters in the cerebrospinal fluid (CSF) during stimulation. Chronic pallidal stimulation was performed on 23 patients. Fourteen patients (60%) had an improvement in the H&Y scale and 16 patients (70%) showed more than 10% of improvement rate in the Unified Parkinson's Disease Rating Scale (UPDRS) score. Both showed statistic significance. The treatment was effective for tremor and rigidity, on the other hand, less effective for gait disturbance and bradykinesia. There were no serious complications or adverse effects. The concentration of Gamma-aminobutyric acid (GABA) in the CSF significantly increased during stimulation. In a few cases, an increase in the level of dopamine (DA), homovanillic acid (HVA) and noradrenaline (NA) was also seen. We conclude that pallidal stimulation has great effects in patients with PD, especially those who have tremor and/or rigidity as a chief symptom. The mechanism of the treatment would involve an activation of the GABAergic system in the globus pallidus.