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4. A Metric for Evaluating and Comparing Closed-Loop Deep Brain Stimulation Algorithms

Author

Herron, Jeffrey, Velisar, Anca, Malekmohammadi, Mahsa, Bronte-Stewart, Helen, and Chizeck, Howard Jay

Subjects
Quantitative Biology - Neurons and Cognition
Abstract

Objective: Closed-loop deep brain stimulation (DBS) may improve current clinical DBS treatment for neurological movement disorders, but control algorithms may perform differently across patients. New metrics are needed for comparing and evaluating closed-loop algorithm performance that address the specific needs of closed-loop neuromodulation controllers. Approach: A metric is proposed for system performance that includes normalized terms that can be used to compare algorithm performance for a patient. This metric was evaluated using two closed-loop control algorithms that were tested in patients with Parkinson's Disease (PD) who experience rest tremor. Main Results: The metric's resulting balance between tremor treatment and power savings varied on a per patient and algorithm basis. This was expected given how each trial resulted in a variable reduction in stimulation power at the cost of additional tremor for the patient when compared to open-loop stimulation. Significance: The proposed metric will aid in clinical evaluation of new algorithms and provide a benchmark for future system designers. This will be important given the growing potential applications of dynamically adjusted neural stimulation. ClinicalTrials.gov Identifier: NCT02384421., Comment: 9 pages, 3 figures

Published
2016

7. Bradykinesia and Its Progression Are Related to Interhemispheric Beta Coherence

Author

Wilkins, Kevin B., primary, Kehnemouyi, Yasmine M., additional, Petrucci, Matthew N., additional, Anderson, Ross W., additional, Parker, Jordan E., additional, Trager, Megan H., additional, Neuville, Raumin S., additional, Koop, Mandy M., additional, Velisar, Anca, additional, Blumenfeld, Zack, additional, Quinn, Emma J., additional, and Bronte‐Stewart, Helen M., additional

Published
2023
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8. Long-Term Subcortical Electrophysiological Recordings Link Heightened Interhemispheric Subthalamic Beta Synchrony to Progression of Bradykinesia in Parkinson’s Disease

Author

Wilkins, Kevin B., primary, Kehnemouyi, Yasmine M., additional, Petrucci, Matthew N., additional, Anderson, Ross W., additional, Parker, Jordan E., additional, Trager, Megan H., additional, Neuville, Raumin S., additional, Koop, Mandy M., additional, Velisar, Anca, additional, Blumenfeld, Zack, additional, Quinn, Emma J., additional, and Bronte-Stewart, Helen M., additional

Published
2022
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13. Lack of progression of beta dynamics after long‐term subthalamic neurostimulation

Author

Anderson, Ross W., primary, Wilkins, Kevin B., additional, Parker, Jordan E., additional, Petrucci, Matthew N., additional, Kehnemouyi, Yasmine, additional, Neuville, Raumin S., additional, Cassini, Declan, additional, Trager, Megan H., additional, Koop, Mandy M., additional, Velisar, Anca, additional, Blumenfeld, Zack, additional, Quinn, Emma J., additional, Henderson, Jaimie, additional, and Bronte‐Stewart, Helen M., additional

Published
2021
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18. Pathological Beta Burst Dynamics are Conserved Across Different Movements in Parkinsons Disease

Author

Neuville, Raumin S, Anderson, Ross W, Petrucci, Matthew N, Parker, Jordan E, Wilkins, Kevin B, Velisar, Anca, and Bronte-Stewart, Helen M

Abstract

Background: Resting state beta band (13-30 Hz) oscillations represent pathological neural activity in Parkinsons disease (PD). It is unknown whether the peak frequency or dynamics of beta oscillations change among rest, fine, limb and axial movements. This will be critical for the development and feasibility of closed loop deep brain stimulation (DBS) algorithms during resting and movement states. Methods: Subthalamic (STN) local field potentials (LFPs) were recorded from a sensing neurostimulator (Activa PC+S, Medtronic Inc.,) and synchronized to kinematic recordings in twelve PD participants off medication/off STN DBS during thirty seconds of repetitive alternating finger tapping, wrist-flexion extension, stepping in place, and free walking. Beta power peaks and beta burst dynamics were identified by custom algorithms; beta burst dynamics were compared among rest and movement tasks. Results: Resting state burst durations were longer in a PD beta band, which was elevated above the 1/f physiological spectrum compared to an overlapping band (p < 0.001). Beta power peaks were evident during fine, limb, and axial movements in 98% of movement trials; the peak frequencies were similar during movements and at rest. Burst duration, average and peak power were also similar among the four movement tasks across the group but varied within individuals. Conclusions: Prolonged burst durations were a feature of PD bands elevated above and not of PD bands overlapping the 1/f spectrum. The conservation of rest/movement band peak frequency and burst dynamics during different activity states supports the feasibility of successful closed loop DBS algorithms driven by beta burst dynamics during different activities and at rest.

Published
2020
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19. Closed Loop Deep Brain Stimulation for Freezing of Gait

Author

Petrucci, Matthew N., Neuville, Raumin S., Afzal, Muhammad Furqan, Velisar, Anca, Anidi, Chioma M., Anderson, Ross W., Parker, Jordan E., ODay, Johanna J., and Bronte-Stewart, Helen M.

Subjects
genetic structures
Abstract

Freezing of gait (FOG), a devastating symptom of Parkinsons disease (PD), can be refractory to current treatments such as medication and open-loop deep brain stimulation (olDBS). Recent evidence suggests that closed-loop DBS (clDBS), using beta local field potential power from the subthalamic nucleus (STN) as the control variable, can improve tremor and bradykinesia; however, no study has investigated the use of clDBS for the treatment of FOG. In this study, we provide preliminary evidence that clDBS was superior to olDBS in reducing percent time freezing and in reducing freezing behavior (gait arrhythmicity) in two people with PD and FOG, with less total energy delivered. These findings warrant further investigation into the use of clDBS to treat FOG while also minimizing the total energy delivered to maintain a therapeutic effect.

Published
2019
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20. Neural closed-loop deep brain stimulation for freezing of gait

Author

Petrucci, Matthew N., primary, Neuville, Raumin S., additional, Afzal, M. Furqan, additional, Velisar, Anca, additional, Anidi, Chioma M., additional, Anderson, Ross W., additional, Parker, Jordan E., additional, O’Day, Johanna J., additional, Wilkins, Kevin B., additional, and Bronte-Stewart, Helen M., additional

Published
2020
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23. Neural Closed Loop Deep Brain Stimulation for Freezing of Gait

Author

Petrucci, Matthew N., primary, Neuville, Raumin S., additional, Afzal, M. Furqan, additional, Velisar, Anca, additional, Anidi, Chioma M., additional, Anderson, Ross W., additional, Parker, Jordan E., additional, O’Day, Johanna J., additional, Wilkins, Kevin B., additional, and Bronte-Stewart, Helen M., additional

Published
2019
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38. Sixty-hertz stimulation improves bradykinesia and amplifies subthalamic low-frequency oscillations.

Author

Blumenfeld, Zack, Koop, Mandy Miller, Prieto, Thomas E., Shreve, Lauren A., Velisar, Anca, Quinn, Emma J., Trager, Megan H., Brontë‐Stewart, Helen, and Brontë-Stewart, Helen

Subjects
PARKINSON'S disease treatment, DIENCEPHALON, ELECTROENCEPHALOGRAPHY, EVALUATION of medical care, HYPOKINESIA, PARKINSON'S disease, DEEP brain stimulation, DISEASE complications, THERAPEUTICS
Abstract

Background: The objective of this study was to investigate the hypothesis that attenuation of subthalamic nucleus (STN) alpha-/beta-band oscillations is causal to improvement in bradykinesia.Methods: STN local field potentials from a sensing neurostimulator (Activa® PC+S; Medtronic, Inc.) and kinematics from wearable sensors were recorded simultaneously during 60- and 140-Hz deep brain stimulation (DBS) in 9 freely moving PD subjects (15 STNs) performing repetitive wrist flexion-extension. Kinematics were recorded during 20-Hz DBS in a subgroup.Results: Both 60- and 140-Hz DBS improved the angular velocity and frequency of movement (P = 0.002 and P = 0.029, respectively, for 60 Hz; P < 0.001 and P < 0.001, respectively, for 140 Hz), but 60-Hz DBS did not attenuate beta-band power (13-30 Hz). In fact, 60-Hz DBS amplified alpha/low-beta (11-15 Hz, P = 0.007) and attenuated high-beta power (19-27 Hz, P < 0.001), whereas 140-Hz DBS broadly attenuated beta power (15-30 Hz, P < 0.001). Only 60-Hz DBS improved the regularity of angular range (P = 0.046) and 20-Hz DBS did not worsen bradykinesia. There was no correlation between beta-power modulation and bradykinesia.Conclusions: These novel results obtained from freely moving PD subjects demonstrated that both 140- and 60-Hz DBS improved bradykinesia and attenuated high beta oscillations; however, 60-Hz DBS amplified a subband of alpha/low-beta oscillations, and DBS at a beta-band frequency did not worsen bradykinesia. Based on recent literature, we suggest that both 140- and 60-Hz DBS decouple the cortico-STN hyperdirect pathway, whereas 60-Hz DBS increases coupling within striato-STN circuitry. These results inform future algorithms for closed-loop DBS in PD. © 2016 International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Published
2017
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40. Benchmarking of dynamic simulation predictions in two software platforms using an upper limb musculoskeletal model.

Author

Saul, Katherine R., Hu, Xiao, Goehler, Craig M., Murray, Wendy M., Vidt, Meghan E., Daly, Melissa, and Velisar, Anca

Subjects
MUSCULOSKELETAL system, ARM, SIMULATION software, ANTHROPOMETRY, BIOMECHANICS, MATHEMATICAL models
Abstract

Several opensource or commercially available software platforms are widely used to develop dynamic simulations of movement. While computational approaches are conceptually similar across platforms, technical differences in implementation may influence output. We present a new upper limb dynamic model as a tool to evaluate potential differences in predictive behavior between platforms. We evaluated to what extent differences in technical implementations in popular simulation software environments result in differences in kinematic predictions for single and multijoint movements using EMG- and optimization-based approaches for deriving control signals. We illustrate the benchmarking comparison using SIMM–Dynamics Pipeline–SD/Fast and OpenSim platforms. The most substantial divergence results from differences in muscle model and actuator paths. This model is a valuable resource and is available for download by other researchers. The model, data, and simulation results presented here can be used by future researchers to benchmark other software platforms and software upgrades for these two platforms. [ABSTRACT FROM PUBLISHER]

Published
2015
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45. The digital signature of emergent tremor in Parkinson's disease.

Author

Bronte-Stewart H, Gala A, Wilkins K, Pettruci M, Kehnemouyi Y, Velisar A, and Trager M

Abstract

Background: Emergent tremor in Parkinson's disease (PD) can occur during sustained postures or movement that is different from action tremor. Tremor can contaminate the clinical rating of bradykinesia during finger tapping. Currently, there is no reliable way of isolating emergent tremor and measuring the cardinal motor symptoms based on voluntary movements only., Objective: Investigate whether emergent tremor during repetitive alternating finger tapping (RAFT) on a quantitative digitography (QDG) device can be reliably identified and distinguished from voluntary tapping., Methods: Ninety-six individuals with PD and forty-two healthy controls performed a thirty-second QDG-RAFT task and the Movement Disorders Society - Unified Parkinson's Disease Rating Scale Part III (MDS-UPDRS III). Visual identification of tremor during QDG-RAFT was labelled by an experienced movement disorders specialist. Two methods of identifying tremor were investigated: 1) physiologically-informed temporal thresholds 2) XGBoost model using temporal and amplitude features of tapping., Results: The XGBoost model showed high accuracy for identifying tremor (area under the precision-recall curve of 0.981) and outperformed temporal-based thresholds. Percent time duration of classifier-identified tremor showed significant correlations with MDS-UPDRS III tremor subscores (r = 0.50, P < 0.0001). There was a significant change in QDG metrics for bradykinesia, rigidity and arrhythmicity after tremor strikes were excluded (p < 0.01)., Conclusions: Emergent tremor during QDG-RAFT has a unique digital signature and the duration of tremor correlated with the MDS-UPDRS III tremor items. When involuntary tremor strikes were excluded, the QDG metrics of bradykinesia and rigidity were significantly worse, demonstrating the importance of distinguishing tremor from voluntary movement when rating bradykinesia., Competing Interests: Competing Interest Dr. Bronte-Stewart has a provisional patent application (PCT/US2021/043787) for objective measurement of PD symptoms.

Published
2023
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