Bilateral stimulation of the subthalamic nucleus in Parkinson's disease: surgical efficacy and prediction of outcome.
OBJECTIVE
Over the last decade neurosurgery has reemerged as a valid therapy for patients with advanced Parkinson's disease. Previously, we have addressed safety and efficacy of subthalamic nucleus (STN) deep brain stimulation (DBS). In this study, we extended these observations and analyzed factors that affect surgical outcome and its predictive value.


METHODS
Thirty-nine patients were enrolled in an open-label prospective protocol designed to evaluate safety and efficacy of bilateral STN DBS in patients with advanced Parkinson's disease between January 1999 and July 2002. Electrodes were stereotactically implanted with electrophysiological conformation of the target location. All patients were evaluated in the medication 'off' and 'on' state preoperatively and at 3, 6, and 12 months after surgery in medication 'on' and 'off' as well as in the stimulation 'off' and 'on' state. Tests included Unified Parkinson's Disease Rating Scales (UPDRS) as well as timed tests. All data was analyzed by means of Analysis of Variance. For outcome prediction, correlation and linear regression analyses were utilized. Stimulation produced significant improvements in all 'off' mediation conditions, resulting in a 42% improvement in UPDRS III score at 12 months compared to the preoperative status. Stimulation in conjunction with medication did not produce any significant change when compared to the preoperative medication 'on' state. Dyskinesia, motor fluctuations, and duration of 'off' periods were significantly reduced with stimulation. Significant outcome predictor variables were age, preoperative percent change of UPDRS III score from medication 'off' to medication 'on' state, and the duration of disease.


CONCLUSIONS
Bilateral STN DBS produces robust improvements in parkinsonian motor symptoms. Surgical outcome can reliably be predicted.
Parkinson's Disease and Movement Disorders Center at Pennsylvania Hospital, Department of Neurology, University of Pennsylvania, Philadelphia 19107, USA. jaggi@med.upenn.edu
Jurg L
JL
Jaggi
Atsushi
A
Umemura
Howard I
HI
Hurtig
Andrew D
AD
Siderowf
Amy
A
Colcher
Matthew B
MB
Stern
Gordon H
GH
Baltuch
D000328:Adult; D000368:Aged; D000704:Analysis of Variance; D004599:Electric Stimulation Therapy / Q000379:methods / Q000706:statistics & numerical data*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology / Q000601:surgery* / Q000628:therapy; D011237:Predictive Value of Tests; D011446:Prospective Studies; D020531:Subthalamic Nucleus / Q000502:physiology / Q000601:surgery*; D016896:Treatment Outcome