Emotional symptoms and cognitive function outcomes of subthalamic stimulation in Parkinson's disease depend on location of active contacts and the volume of tissue activated.

Background: Subthalamic nucleus (STN) deep brain stimulation (DBS) is an effective treatment for Parkinson's disease (PD), that can improve patients' motor and non-motor symptoms. However, there are differences in the improvement of patients' emotional symptoms and cognitive function.

Objective: To investigate the impact of active contact location and the volume of tissue activated (VTA) on patients' emotional symptoms and cognitive function in STN-DBS in PD.

Methods: A total of 185 PD patients were included in this study. We evaluated them using the Movement Disorder Society-Unified Parkinson's Disease Rating Scale, Hamilton Anxiety Scale (HAM-A), Hamilton Depression Scale (HAM-D), Montreal Cognitive Assessment (MoCA), and Mini-Mental State Examination (MMSE) scales at the preoperative, 1- and 12-month postoperative time points. Leads were positioned in standard space using the Lead-DBS toolbox, and VTA was calculated for analysis.

Results: When the lead active contact was closer to the ventral side of the STN, the patients' HAM-A improvement rate was higher, and when the active contact was closer to the anterior and dorsal sides of the STN, the patients' MoCA improvement rate was higher. Stimulation of the sensorimotor zone was more favorable to the improvement of HAM-A and HAM-D in patients. And, the stimulation of the associative zone was more favorable to the improvement of MoCA in patients.

Conclusion: Our results provide evidence that the 12-month outcomes of cognitive function and emotional symptoms in PD patients with STN-DBS were closely related to the specific location of the active contacts in the STN and influenced by the VTA.