Deep Brain Stimulation Programming in Parkinson's Disease Using Functional Motor Symptom Response Tuning Maps (P04.180)

OBJECTIVE: To capture Parkinson9s disease (PD) motor symptom severities across a range of deep brain stimulation (DBS) settings during outpatient programming and determine how these functional motor responses change across programming sessions. BACKGROUND: Once pharmaceutical interventions are no longer effective in the management of PD motor symptoms, DBS surgery may be considered. While guidelines exist for DBS parameter optimization, efficacy is greatly dependent on programming experience and tools available to track response to stimulation over time. DESIGN/METHODS: Subjects underwent routine outpatient programming sessions at approximately one, two, and four months following DBS surgery. During the programming, subjects were equipped with a finger-worn motion sensor which recorded kinematic data while subjects performed standardized tasks to evaluate rest and postural tremor and hand movement speed and amplitude deficits at various stimulation settings. Tuning maps displaying 0-4 color-coded symptom severity scores versus stimulation amplitude and contact were generated using clinician and clinically-validated motion-sensor ratings. In order to better compare tuning maps across programming sessions, stimulation voltage was converted to therapeutic current based on electrode impedance. RESULTS: Electrode impedance increased and therefore higher stimulation amplitudes were necessary over subsequent programming sessions. High agreement between clinician and algorithm scoring was achieved for rest and postural tremor; however, clinician scores were more correlated with hand movement amplitude than speed deficits. Lastly, because electrode impedance did not remain constant across programming sessions, the stimulation amplitude threshold where the therapeutic effect occurred differed when comparing the voltage- versus current-based tuning maps. CONCLUSIONS: Functional motor response to stimulation and electrode impedance can vary over time, and as a result optimizing programming outcomes can be complex and challenging. Motion sensor tuning maps provide a standardized and objective approach to quickly visualize the therapeutic response to stimulation within and across programming sessions. Supported by: NIH NIA 7R44AG033520-04. Disclosure: Dr. Mera has received personal compensation for activities with Great Lakes NeuroTechnologies Inc. as an employee. Dr. Vitek has received personal compensation for activites with St. Jude Medical, Boston Scientific Corporation, Medtronic, Inc., NeuoNexus, and Great Lakes NeuroTechnologies, Inc. Dr. Vitek has received research support from Boston Scientific Corporation. Dr. Giuffrida has received personal compensation for activities with Great Lakes NeuroTechnologies Inc., as an employee. Dr. Giuffrida holds stock and/or stock options in Great Lakes NeuroTechnologies.