Category: Surgical Therapy: Parkinson's Disease
Objective: Use local field potentials (LFP) to inform longitudinal clinical decision making.
Background: Genetic status, clinical and stimulation parameters affect outcomes in PD STN DBS. Suppression of STN beta oscillatory activity improves motor symptoms. A sensing-enabled implantable pulse generator (IPG) allows detection and longitudinal monitoring of STN beta oscillatory activity and can assist in optimizing stimulation.
Method: A PD-DBS patient with bilateral STN DBS using a segmented lead and a sensing-enabled IPG was followed for 15 months. Motor responses were assessed with UPDRS-III at each clinic visit prior to DBS adjustment. Genetic status was obtained as part of the ROPAD study (NCT03866603). Bipolar local field potentials (LFP) differential recording sensing maps between contact levels, contact level segment pairs and direction, longitudinal LFP magnitude tracking, individually scaled 24-hour blocks and patient triggered LFP recordings were analyzed using MATLAB. Stimulation was initiated with a single active contact bilaterally in the monopolar configuration. Based on neurophysiological monitoring and clinical response, contact configuration was eventually changed to two active negative contacts and directional segment mode. The frequency of interest (FOI) ranged from 10.74 to 25.39 Hz, with the adjustment dependent on clinical response to stimulation parameters and medication.
Results: No pathogenic variants were identified in LRRK2, GBA, SNCA, PRKN, PINK1, GCH1, PLA2G6, ATP13A2, FBXO7, POLG, SYNJ1, VPS13C, SLC6A3, and DNAJC6. Daily levodopa requirements were <100 mg due to good symptom control postoperatively. Brain and segment survey LFP peaks were suppressed by levodopa. The timeline identified the duration of the microlesion effect and showed a clear effect of contralateral stimulation on the ipsilateral hemisphere. Serial UPDRS III scores remained low, fluctuating with interval increases that prompted DBS adjustments informed by monitoring the FOI.
Conclusion: The analysis of this sporadic PD-DBS case supports the utility of longitudinal LFP magnitude tracking in determining the microlesion effect duration to inform the timing of initial programming, the impact of contralateral stimulation on the ipsilateral hemisphere, and the utility of adjusting the FOI in the context of clinical response.
To cite this abstract in AMA style:
K. Markopoulou, P. Warnke. Utility of neurophysiological markers in clinical management of subthalamic nucleus (STN) deep brain stimulation (DBS) in Parkinson’s disease (PD)-a case report. [abstract]. Mov Disord. 2023; 38 (suppl 1). https://www.mdsabstracts.org/abstract/utility-of-neurophysiological-markers-in-clinical-management-of-subthalamic-nucleus-stn-deep-brain-stimulation-dbs-in-parkinsons-disease-pd-a-case-report/. Accessed November 21, 2024.« Back to 2023 International Congress
MDS Abstracts - https://www.mdsabstracts.org/abstract/utility-of-neurophysiological-markers-in-clinical-management-of-subthalamic-nucleus-stn-deep-brain-stimulation-dbs-in-parkinsons-disease-pd-a-case-report/