Neuropsychological effects of bilateral deep brain stimulation of the subthalamic nucleus in Parkinson's disease.

Although a relatively new technique, bilateral deep brain stimulation (DBS) of the subthalamic nucleus (STN) for the treatment of advanced cases of Parkinson's disease (PD) shows considerable promise. While the benefits of the STN stimulation for the treatment of motor symptoms of PD are well established, some studies have reported negative neuropsychological outcomes, especially in elderly patients. The objective of the present study was to investigate the neuropsychological effects of bilateral STN-DBS in a small sample of elderly patients with PD. Six patients with PD (mean age 73.0 +/- 10.45 years) were assessed both before and approximately 6 months after DBS surgery in six neuropsychological domains. These domains included orientation, estimated IQ, attention/working memory, language, memory, and visual-spatial functioning. Additionally, depressive symptoms were assessed using the Geriatric Depression Scale. Daily doses of antiparkinsonian medications, in levodopa equivalents, were also compared pre- and postoperatively. Antiparkinsonian medications were reduced postoperatively by a mean of 65%, from a mean levodopa equivalent dosage of 987 mg/day to 346 mg/day. Category fluency, a word generation task within the language domain, was the only test in which participants demonstrated a statistically significant decline in performance. Participants demonstrated a mean score decrease of 41% (p < 0.05) in category fluency. The pathophysiology of the observed deficit remains ill defined. However, despite a small sample size, the study provides further evidence that bilateral STN-DBS in PD patients can be associated with negative neuropsychological outcome in word fluency, especially in elderly patients. Implications regarding patient selection for bilateral STN-DBS and recommendations for future research are further discussed.

Bordini BJ ，Garg A ，Gallagher CL ，Bell B ，Garell PC ... -  《STEREOTACTIC AND FUNCTIONAL NEUROSURGERY》

The effects of bilateral subthalamic nucleus deep brain stimulation (STN DBS) on cognition in Parkinson disease.

Heo JH ，Lee KM ，Paek SH ，Kim MJ ，Lee JY ，Kim JY ，Cho SY ，Lim YH ，Kim MR ，Jeong SY ，Jeon BS ... -  《JOURNAL OF THE NEUROLOGICAL SCIENCES》

Cognition following bilateral deep brain stimulation surgery of the subthalamic nucleus for Parkinson's disease.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by significant motor dysfunction and various non-motor disturbances, including cognitive alterations. Deep brain stimulation (DBS) is an increasingly utilized therapeutic option for patients with PD that yields remarkable success in alleviating disabling motor symptoms. DBS has additionally been associated with changes in cognition, yet the evidence is not consistent across studies. The following review sought to provide a clearer understanding of the various cognitive sequelae of bilateral subthalamic nucleus (STN) DBS while taking into account corresponding neuroanatomy and potential confounding variables. A literature search was performed using the following inclusion criteria: (1) at least five subjects followed for a mean of at least 3 months after surgery; (2) pre- and postoperative cognitive data using at least one standardized measure; (3) adequate report of study results using means and standard deviations. Two recent meta-analyses found mild post-operative impairments in verbal learning and executive function in patients who underwent DBS surgery. However, studies have revealed improved working memory and psychomotor speed in the 'on' vs 'off' stimulation state. A deficit in language may be a consequence of the surgical procedure. While cognitive decline has been observed in some domains, our review of the data suggests that STN DBS is a worthwhile and safe method to treat PD.

Halpern CH ，Rick JH ，Danish SF ，Grossman M ，Baltuch GH ... -  《-》

Neuropsychological performance following staged bilateral pallidal or subthalamic nucleus deep brain stimulation for Parkinson's disease.

Rothlind JC ，Cockshott RW ，Starr PA ，Marks WJ Jr ... -  《JOURNAL OF THE INTERNATIONAL NEUROPSYCHOLOGICAL SOCIETY》

Pallidal vs subthalamic nucleus deep brain stimulation in Parkinson disease.

Anderson VC ，Burchiel KJ ，Hogarth P ，Favre J ，Hammerstad JP ... -  《archives of neurology》