Subthalamic nucleus (STN) lesions or high-frequency stimulations could
improve parkinsonian symptoms in monkeys treated by MPTP. We have app
lied the procedure of chronic stimulation to the STN in severely disab
led parkinsonian patients. This article presents the case of the first
patient operated on bilaterally. Bilateral STN stimulation has greatl
y improved akinesia and rigidity. The benefit was maintained less than
or equal to 15 months after surgery. Unilateral stimulation induced m
otor effects mainly in contralateral limbs. Further studies are needed
to evaluate the value of this procedure in the treatment of Parkinson
's disease.