Directional Deep Brain Stimulation Programming in Parkinson's Disease and Essential Tremor Patients: An Institution-Based Study

Deep brain stimulation (DBS) and the use of directional subsegmental stimulation have significantly advanced symptom management in patients with Parkinson's disease (PD) and essential tremor (ET). This study examines the use of directional programming in a tertiary care center. We retrospectively reviewed medical records of 12 PD patients (all with bilateral subthalamic nucleus (STN) implants) and 13 ET patients (12 with bilateral and 1 with unilateral ventral intermediate nucleus (VIM) implants) who received directional leads. Clinical parameters such as the Fahn-Tolosa-Marin (FTM) Tremor Rating Scale for ET and the Unified Parkinson's Disease Rating Scale (UPDRS) for PD were assessed before and after the procedure. Programming parameters and the reasons for switching to directional stimulation were also evaluated. Directional programming was used in 11 of 12 (92%) PD patients and 12 of 13 (92%) ET patients on at least one side. Among PD patients, 58% (7/12) used directional programming to avoid side effects, while 25% (3/12) used it to improve therapeutic benefit. Similarly, among ET patients, 64% (7/11) used directional programming to avoid side effects, and 33% (4/12) experienced improved tremor control with directional configurations. Our study demonstrates high utilization of directional programming. The findings suggest directional stimulation improves efficacy by reducing side effects and enhancing therapeutic outcomes. These results may support the early adoption of directional programming in managing PD and ET patients.