Deep brain stimulation with a PINS device in Parkinson's disease: long-term follow-up

Abstract

Objective To evaluate the long-term safety and efficacy of subthalamic nucleus deep brain stimulation (STN-DBS) with a PINS stimulator in Parkinson's disease (PD). Methods Fifty patients received PINS device implantation in the subthalamic nucleus from November 2009 to August 2012 at Neurosurgery Department of Beijing Tiantan Hospital, Capital Medical University and were retrospectively enrolled into this study. The effects of stimulation on motor score, activities of daily living, the levodopa-equivalent dose, and the side effects were analyzed for all 50 patients with PD undergoing bilateral STN-DBS based on the Unified Parkinson's Disease Rating Scale (UPDRS). The scores were collected at baseline in two conditions (off medication) and at 6 months, 1, 2, and 5 years of follow-up with stimulation in the absence or presence of medication. Results The 50 patients were followed up for 5.0-7.5 years. At 6 months, 1, 2, and 5 years of follow-up, our results showed a significant decrease from baseline in both activities of daily living and motor scores (P<0.01); the daily levodopa-equivalent dose decreased compared with baseline (P<0.01). In the condition of medication off, the UPDRS Ⅲ scores decreased by 71%, 69%, 69%, 62% at 6 months, 1 year, 2 years, 5 years, respectively; and the improvement rates of UPDRS Ⅱ scores were 71%, 71%, 71%, 62%, at 6 months, 1 year, 2 years, 5 years, respectively. The daily levodopa-equivalent dose decreased by 31%, 37%, 35%, 27% at 6 months, 1 year, 2 years, 5 years, respectively. There was no death or intracranial hemorrhage in the study. Five patients suffered from transient mental and psychiatric disturbances. Two cases of infection, 1 case of cerebrospinal fluid leakage, 1 case of ptosis, and 1 case of dysphonia were observed during the follow-up. The 2 cases with preoperative dyskinesia had no significant improvement including 1 reported disappearance of dyskinesia and 1 with remaining dyskinesia following adjustment of programming parameters. Conclusion STN-DBS with the PINS device could significantly improve the motor symptoms and life quality of PD patients, which demonstrated safety and efficacy in long-term study. Key words: Parkinson disease; Deep brain stimulation; Subthalamic nucleus