Testing different patterns of implanted brain stimulation

This is an open-label, non-randomized, proof-of-concept comparison of clinical vs. research stimulation patterns in patients with Parkinson's disease (PD) being treated with Deep Brain Stimulation (DBS) through the Medtronic Percept PC DBS device. The investigators hypothesize that stimulation patterns designed to better target excessive synchrony in a patient-tailored manner may result in more efficient and effective therapy with fewer side effects. Medtronic 3rd-generation sensing implantable neural stimulator, Percept PC, is FDA-approved for treating PD. The Percept PC device features BrainSense, the first and only available sensing technology for deep brain stimulation. BrainSense technology allows the device to capture and record brain signals (local field potentials, or LFP) using the brain-implanted DBS lead, while simultaneously delivering therapeutic stimulation. Investigators plan to enroll and complete investigations in 15 study subjects total, who have been previously implanted with the Medtronic Percept PC for the treatment of PD, and who are optimized for clinical stimulation and anti-Parkinsons medication. Investigations will be performed in UNMC Movement Disorders Clinic, UNMC Neurosurgery Lab, and UNO Biomechanics Research Building, Gait Lab. Subjects will receive research stimulation patterns and the effect on PD motor symptoms will be assessed via Unified Parkinsons Disease Rating Scale (UPDRS)-part III and gait measures. Videotaping of patient UPDRS-III testing and gait will be obtained.

Parkinson's disease (PD) is a neurodegenerative disorder characterized by both motor and non-motor symptoms. Motor symptoms of PD include the clinical triad of tremor, rigidity, and bradykinesia, and typically lead to the initial diagnosis. While there is yet no cure for PD, medical and surgical therapies have been developed that effectively target the motor symptoms of PD. Patients with PD who demonstrate significant motor fluctuations and dyskinesia are considered for subthalamic nucleus (STN) deep brain stimulation (DBS) surgery. Therapeutic DBS leads to a reduction in pathological neuronal synchronization seen in PD. While continuous high-frequency stimulation is effective for ameliorating motor symptoms, the investigators hypothesize that different stimulation patterns which are designed to better target excessive synchrony in a patient-tailored manner, may result in more efficient and effective therapy with fewer side effects. This overarching hypothesis is supported by prior foundational preclinical and clinical research. Medtronic has developed proprietary technology that allows implantable neural stimulators (INS) to deliver both standard clinical electrical stimulation therapy and to record bioelectric data (i.e. local field potentials; LFPs) through DBS leads implanted in the brain. Medtronic's 3rd-generation sensing DBS INS, Percept PC, is FDA-approved for treating PD and can be used to explore unique biomarkers of brain state changes associated with activities of daily living and disease symptomatic states. This research will use Percept PC INS latent capabilities to deliver research stimulation. Importantly, all stimulation in this research project will be delivered using charge-balanced pulses, in compliance with all FDA safety guidelines including frequency (≤ 250 Hz) and charge density (30 µC/cm2/phase). At the conclusion of the research study, standard clinical stimulation will be re-activated.