Thalamic Local Field Potentials and Closed‐Loop Deep Brain Stimulation in Orthostatic Tremor

BackgroundOrthostatic tremor (OT) is a rare movement disorder characterized by a feeling of unsteadiness and a high‐frequency tremor in the legs (13–18 Hz) relieved by sitting or walking.ObjectivesThe aims were to study the brain electrophysiology captured chronically in a person with medication‐refractory OT while standing and walking and in the semi‐recumbent position using bilateral ventral intermedius nucleus deep brain stimulation (DBS) (Medtronic Percept PC) and to describe the clinical use of closed‐loop DBS.MethodsA sensing survey was used to capture baseline local field potentials (LFPs) while standing. Livestreamed LFPs were synchronized with data collected from two accelerometers (legs) and gait analysis during OFF stimulation and continuous and closed‐loop DBS.ResultsStrong oscillatory coupling between thalamic LFP and leg tremor with significant coherence at 14.65 Hz was found during weight‐bearing. Single‐threshold adaptive DBS (sensing at this frequency) was superior to continuous stimulation in reducing tremor and stimulation‐related gait ataxia.ConclusionsThis study provides new insights into both the pathophysiology and management of OT. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.