Globus pallidus stimulation in advanced Parkinson's disease

Area of Science:

• Neurosurgery
• Neurology
• Movement Disorders

Background:

• Globus pallidus internus (GPi) deep brain stimulation (DBS) is a therapeutic option for Parkinson's disease (PD) patients with severe levodopa-induced dyskinesias (LID) and motor fluctuations.
• Limited data exists on GPi DBS outcomes compared to subthalamic nucleus DBS.

Purpose of the Study:

• To evaluate the efficacy and safety of unilateral and bilateral GPi DBS in PD patients with severe LID and motor fluctuations.
• To compare the outcomes of unilateral versus bilateral GPi DBS.

Main Methods:

• Retrospective analysis of 20 PD patients (9 unilateral, 11 bilateral) undergoing GPi stimulation.
• Assessment of motor symptoms using Unified Parkinson's Disease Rating Scale (UPDRS) part III.
• Evaluation of dyskinesia using Abnormal Involuntary Movement Scale (AIMS) and UPDRS part IVa.

Main Results:

• Bilateral GPi DBS reduced off-period motor scores by 46% and on-period scores by 18% at 7 months.
• Unilateral GPi DBS reduced off-period motor scores by 18%.
• Dyskinesia severity decreased by 76% and was sustained at 35 months follow-up. Medication dosage remained unchanged.

Conclusions:

• Unilateral and bilateral GPi DBS provide sustained benefits for PD patients with severe LID.
• Bilateral GPi DBS offers greater improvement in motor fluctuations, while unilateral GPi DBS can also provide significant, lasting benefits without altering medication.
• GPi DBS is a safe and effective treatment for selected PD patients.