LONG-TERM EFFECT OF ELECTROSTIMULATION OF THE SUBTHALAMIC - NUCLEUS IN BRADYKINETIC-RIGID PARKINSONS-DISEASE

The motor effects of unilateral stimulation of the subthalamic nucleus on hypokinesia were studied in two patients 58 and 52 years old, both modified Hoehn and Yahr 2.5, at 16 and 15 months after the implantati on of a quadripolar electrode (Medtronic). Motor UPDRS, time in the pe gboard test, wanting time, tapping, and serial reaction times were rec orded. Chronic unilateral stimulation was associated with reversible i mprovement of measures of reaction time and hypokinesia > 1 year after the stereotactic electrode implantation. The beneficial effect was ma inly contralateral to the stimulation. However, improvement of axial f unctions was also observed (phonation, walking).