Session Information
Date: Wednesday, September 25, 2019
Session Title: Physiology and Pathophysiology
Session Time: 1:15pm-2:45pm
Location: Les Muses, Level 3
Objective: To examine the relationship between local field potential (LFP) activity recorded from directional deep brain stimulation (DBS) leads in the internal segment of the globus pallidus (GPi) to the development of parkinsonian motor signs in Parkinson’s disease (PD) patients.
Background: Beta LFP activity in the subthalamic nucleus (STN) has been hypothesized to underlie the development of bradykinesia in patients with PD. There are only a few studies, however, that have examined whether such activity is present in GPi in PD, or what the relationship of such LFP activity is to movement or severity of PD motor signs. Fewer still have addressed these questions using segmented leads that have greater spatial resolution compared to standard non-segmented leads.
Method: Pallidal LFPs were recorded from GPi with externalized, segmented DBS leads in three PD patients, in the off state, during rest, active and passive movement tasks. Lead location and orientation were determined using pre-operative high resolution 7T MR images registered to post-operative CT scans.
Results: Both high (>20) and low (<20) beta band LFP activity were modulated during an active reach-to-target task, but specific to each subject. One subject showed high and low beta bands modulating coherently in-phase, while in a second subject the phase between bands varied. A third subject showed only low beta modulation. The passive motor task of the upper extremity also showed subject-specific modulation of LFP activity with rigidity and, as with the active movement task, the frequency bands were subject specific.
Conclusion: LFP activity in the 5-35 Hz range is present in the GPi, is modulated with movement, corresponded with the severity of motor signs and is remarkably patient-specific. These data would suggest that in order to optimize closed-loop DBS algorithms it will be important to account for subject specific differences in symptom specific LFP related activity that occurs at rest, to that which occurs during movement. These algorithms will also need to be target specific and based on each patient’s unique physiological profile.
To cite this abstract in AMA style:
J. Aman, L. Johnson, D. Sanabria, J. Wang, M. Hill, S. Cooper, L. Schrock, M. Petrucci, G. Molnar, C. Mackinnon, R. Patriat, N. Harel, M. Park, J. Vitek. Movement and symptom-modulated local field potentials in globus pallidus internus of Parkinson’s disease [abstract]. Mov Disord. 2019; 34 (suppl 2). https://www.mdsabstracts.org/abstract/movement-and-symptom-modulated-local-field-potentials-in-globus-pallidus-internus-of-parkinsons-disease/. Accessed November 24, 2024.« Back to 2019 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/movement-and-symptom-modulated-local-field-potentials-in-globus-pallidus-internus-of-parkinsons-disease/