Follow-up of bilateral subthalamic deep brain stimulation for Parkinson's disease

To demonstrate the effects of bilateral subthalamic deep brain stimulation (STN-DBS) in the treatment of Parkinson's disease (PD) after 4-45 months' follow-up.

Between 04/01 and 12/04, 46 PD patients were operated on with bilateral STN-DBS. All of them were evaluated with Unified Parkinson's Disease Rating Scale (UPDRS) parts II-V before surgery and 4-45 months after surgery. The amelioration of miscellaneous symptoms and decrease of medication dose, respectively, were compared. Main side effects were observed.

After surgery, both the score of activities of daily living (ADL) and the UPDRS motor score decreased significantly (p < 0.001). Among the PD symptoms, tremor was improved best. Rigidity, bradykinesia, axial symptoms, facial expression and dyskinesia were all improved, although to a lesser extent, while speech was not improved. Medication dose was decreased significantly (p < 0.001). According to the time of follow-up, 4 groups were classified (4-12 months, 13-24 months. 25-36 months and 37-45 months group). ADL, UPDRS motor score and dyskinesia subscore improvement were compared among these groups. No significant difference existed. No life threatening complications occurred. Main side effects included hypophonia, dyskinesia, confusion, depression.

Bilateral STN-DBS is a satisfying surgical method for the treatment of advanced PD. It can improve the cardinal PD symptoms up to 45 months. Complications and side effects were rare and usually temporary or reversible.