We selected patients implanted with directional lead with at least 2 months of programming. This included 13 ET patients (targets- bilateral Vim) and 12 PD patients (target bilateral –STN) that were implanted with directional leads Abbott SJM 6173 (1.5mm spacing) or Abbott SJM 6172 (0.5 mm spacing) leads. We evaluated their clinical ratings (Fahn Tolosa Marsden Tremor Rating Scale or Unified Parkinson Disease Rating scale) before and after the procedure. We performed retrospective reviews of their active DBS settings and reasons that lead to directional settings.  

In 10/13 ET and 11/13 PD patients had at least one side with active directional stimulation. 5 ET patient and 9 PD patients ended with directional configuration bilaterally. Factors that lead to directional programming in ET patients included – paresthesia in 1 patient, tingling and capsular effects in 1 patient, capsular effects in 6 patients, better tremor control in 2 patients. Factors that lead to directional programming in PD patients included – Capsular side effects in 7 patients, autonomic dysfunction including feeling flushed in 1 patient, and improved motor symptom control including toe curling and dyskinesia in 1 patient.

In our experience, we see high uptake in directional stimulation in PD and ET.  Our approach was based on evaluating directional only when conventional stimulation was limited by side effects and not proactively evaluating directionality. We anticipate higher uptake with a change in approach to that end.