STEREOTAXIC VENTRAL PALLIDOTOMY FOR PARKINSONS-DISEASE

Eighteen patients with medically intractable Parkinson's disease that was characterized by bradykinesia, rigidity, and marked ''on-off' fluc tuations underwent stereotactic ventral pallidotomy under local anesth esia. Targeting was aided by anatomic coordinates derived from the MRI , intraoperative cell recordings, and electrical stimulation prior to lesioning. A nonsurgically treated group of seven similarly affected i ndividuals was also followed. Assessment of motor function was made at baseline and at S-month intervals for 1 year. Following the lesioning , patients improved in bradykinesia, rigidity, resting tremor, and bal ance with resolution of medication-induced contralateral dyskinesia. W hen compared with preoperative baseline, all quantifiable test scores after surgery improved significantly with the patients off medications for 12 hours: UPDRS by 65%, and CAPIT subtest scores on the contralat eral limb by 38.2% and the ipsilateral limb by 24.2%. Walk scores impr oved by 45%. Medication requirements were unchanged, but the patients who had had surgery were able to tolerate larger doses because of redu ced dyskinesia. Ventral pallidotomy produces statistically significant reduction in parkinsonism and contralateral ''on'' dyskinesia without morbidity or mortality and with a short hospitalization in Parkinson' s disease patients for whom medical therapy has failed.