ASSESSMENT OF MOTOR FUNCTION AFTER STEREOTAXIC PALLIDOTOMY

Despite a paucity of controlled data, stereotactic pallidotomy is incr easingly used for the treatment of advanced Parkinson's disease (PD). To study the efficacy of the procedure on the cardinal PD features of rigidity, tremor, bradykinesia, and postural instability, we blindly r ated randomized videos of 34 patients recorded in the ''off'' state im mediately before and 3 months after unilateral stereotactic lesioning of the globus pallidus internus. Total ''off' time Unified Parkinson's Disease Rating Scale motor scores improved 13.6% from 28.9 +/- 7.5 to 25.0 +/- 7.0 (p < 0.001). Particularly robust improvement was seen in contralateral tremor, gait, and arising from a chair (p < 0.001). Sig nificant improvement was also seen in ipsilateral tremor, contralatera l and some ipsilateral dexterity measures, and body bradykinesia. Most other features tended toward improvement but did not reach statistica l significance. We conclude that pallidotomy is a safe and effective t reatment of parkinsonian symptoms, many of which improve bilaterally.