Congress of neurological surgeons systematic review and evidence-based guideline on subthalamic nucleus and globus pallidus internus deep brain stimulation for the treatment of patients with Parkinson's disease: Executive summary

QUESTION 1: Is bilateral subthalamic nucleus deep brain stimulation (STN DBS) more, less,or as effective as bilateral globus pallidus internus deep brain stimulation (GPi DBS) intreating motor symptoms of Parkinson's disease, as measured by improvements in UnifedParkinson's Disease Rating Scale, part III (UPDRS-III) scores?RECOMMENDATION: Given that bilateral STN DBS is at least as effective as bilateral GPiDBS in treating motor symptoms of Parkinson's disease (as measured by improvements inUPDRS-III scores), consideration can be given to the selection of either target in patientsundergoing surgery to treat motor symptoms. (Level I)QUESTION 2: Is bilateral STN DBS more, less, or as effective as bilateral GPi DBS in allowingreduction of dopaminergic medication in Parkinson's diseaseffRECOMMENDATION: When the main goal of surgery is reduction of dopaminergicmedications in a patient with Parkinson's disease, then bilateral STN DBS should beperformed instead of GPi DBS. (Level I)QUESTION 3: Is bilateral STN DBS more, less, or as effective as bilateral GPi DBS in treatingdyskinesias associated with Parkinson's diseaseffRECOMMENDATION: There is insufcient evidence to make a generalizable recommendation regarding the target selection for reduction of dyskinesias. However, when thereduction of medication is not anticipated and there is a goal to reduce the severity of"on"medication dyskinesias, the GPi should be targeted. (Level I)QUESTION 4: Is bilateral STN DBS more, less, or as effective as bilateral GPi DBS inimproving quality of life measures in Parkinson's diseaseffRECOMMENDATION: When considering improvements in quality of life in a patient undergoing DBS for Parkinson's disease, there is no basis to recommend bilateral DBS in 1 targetover the other. (Level I)QUESTION 5: Is bilateral STN DBS associated with greater, lesser, or a similar impact onneurocognitive function than bilateral GPi DBS in Parkinson diseaseffRECOMMENDATION: If there is signifcant concern about cognitive decline, particularly inregards to processing speed and working memory in a patient undergoing DBS, then theclinician should consider using GPi DBS rather than STN DBS, while taking into consideration other goals of surgery. (Level I)QUESTION 6: Is bilateral STN DBS associated with a higher, lower, or similar risk of mooddisturbance than GPi DBS in Parkinson's diseaseffRECOMMENDATION: Ifthere is signifcant concern abouttherisk of depression in a patientundergoing DBS, then the clinician should consider using pallidal rather than STN stimulation, while taking into consideration other goals of surgery. (Level I)QUESTION 7: Is bilateral STN DBS associated with a higher, lower, or similar risk of adverseevents compared to GPi DBS in Parkinson's diseaseff RECOMMENDATION: There is insufcient evidence to recommend bilateral DBS in 1 targetover the other in order to minimize the risk of surgical adverse events.The full guideline can be found at: https://www.cns.org/guidelines/deep-brainstimulation-parkinsons-disease.