CHRONIC ANTERIOR PALLIDAL STIMULATION FOR PARKINSONS-DISEASE

We present the case of a 51-year-old female who had a four-year histor y of Parkinson's disease with severe ''on-off'' and disabling progress ion of symptoms on chronic levodopa therapy. After obtaining FDA appro val, we implanted a Medtronic deep brain stimulation lead stereotactic ally into the right anterior pallidum contralateral to her most sympto matologic side. Intra-operative stimulation trials at 100 Hz caused re producible reversal of akinetic symptoms and simultaneous microelectro de recording of the posteroventral pallidum revealed decreased neural activity during anterior pallidal stimulation. The patient was evaluat ed pre-operatively and postoperatively using the Hoehn and Yahr Stagin g Scale, the Unified Parkinson's Disease Rating Scale (UPDRS), videota pe, and a computerized data glove. Six months after implantation, the total UPDRS score was decreased from 68 to 8 and Hoehn and Yahr Stagin g improved from 3.0 to 1.5 during periods of chronic high frequency st imulation. Dramatic improvements in tremor, dystonia, bradykinesia, an d akinesia were noted within seconds of stimulator activation and were also objectively measured using a computerized data glove. This case reveals the potential for therapeutic pallidal stimulation for Parkins on's akinetic symptomatology.