Objective: Subthalamic nucleus (STN)-deep brain stimulation (DBS) in Parkinson's disease (PD) patients affects not just focused target areas but also diffuse brain networks. The effect of this network modulation on nonmotor DBS effects is not fully understood. By concentrating on the sleep domain, the authors comprehensively determined the influence of electrode location and related structural/functional connections on changes in probable rapid eye movement (REM) sleep behavior disorder (pRBD) symptoms after STN-DBS, which has been reported to ameliorate, deteriorate, or remain constant.
Methods: Preoperative and postoperative pRBD symptoms were documented in 60 PD patients. The volumes of tissue activated (VTAs) were assessed on the basis of individual electrode reconstructions and merged with normative connectome data to identify structural/functional connections associated with VTAs. The entire cohort was used to construct connection models that explained changes in pRBD symptoms, as well as to perform cross-validations.
Results: Structural/functional connectivity was associated with pRBD symptom changes during STN-DBS. Changes in pRBD symptoms were predicted using an ideal structural connection map. Prefrontal connection was related with improved pRBD symptoms, whereas sensorimotor connectivity was associated with deterioration.
Conclusions: Recovery of pRBD symptoms was predicted on the basis of the fibers connecting the STN electrode to prefrontal regions. These findings implied that the placement of STN-DBS leads influences the fibers to prefrontal regions and may be used to enhance treatment of pRBD symptoms; however, further prospective studies are needed to validate these findings.
Keywords: Parkinson’s disease; REM sleep behavior disorder; connectomes; deep brain stimulation; functional neurosurgery.