Objective: We investigated the factors affecting the indications and effectiveness of aDBS based on the correlation between self-recorded on/off-state and beta oscillations in Parkinson’s disease (PD).

Background: aDBS enables a closed-loop stimulation based on real-time sensing of the local field potentials (LFPs) in patients with PD. Theoretically, the effectiveness of aDBS depends on a high correlation between the symptomatic on/off-state and the height of the beta-band peak. However, several factors can affect the correlation such as external noise (including EKG), antiparkinsonian medication, and a slight dislocation of DBS leads. Identification of some indicators for aDBS is a key imperative to achieve a high effectiveness compared to conventional continuous DBS (cDBS).

Method: We included 4 patients with PD with wearing-off. All patients underwent bilateral subthalamic nucleus DBS surgery and were implanted Percept PC (Medtronic). After starting stimulation, the patients recorded on-state and off-state when they perceived a change in the condition. Subsequently, the correlation between the patient’s self-recorded on/off-state and the height of the beta-band peak was evaluated by calculating the sensitivity and specificity of beta-band peak. For sensitivity, we denoted the patients’ off-state with the beta-band peak over the upper threshold. For specificity, we denoted the patients’ on-state with the beta-band peak below the lower threshold.

Results: On reviewing the LFPs of Case 1, we found that pramipexole 1.5 mg per day strongly suppressed the beta-band peak even when the patient had recorded off-state, suggesting that restriction of some medications may be necessary for achieving high sensitivity. Case 1 was excluded from the study for not performing self-recording of ON. The beta-band peak tended to show a low sensitivity in the other 3 patients (34.4%, 18.2%, and 44.6%, respectively), indicating an undesirable tendency for not increasing the stimulation when the patient was off-state. However, the specificity was relatively high (42.1%, 87.5%, and 100%), indicating a favorable tendency for minimal unnecessary increase in the stimulus intensity when the patient was on-state.

Conclusion: Some medications may affect the performance of aDBS. The sensitivity and specificity of the beta band peak can be a crucial indicator of the effectiveness of aDBS. Further study to verify this hypothesis is currently underway.

« Back to 2023 International Congress

MDS Abstracts - https://www.mdsabstracts.org/abstract/factors-affecting-adaptive-deep-brain-stimulation-adbs-indications-in-parkinsons-disease/