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Fasano A, Mure H, Oyama G, Murase N, Witt T, Higuchi Y, Singer A, Sannelli C, Morelli N. Subthalamic nucleus local field potential stability in patients with Parkinson's disease. Neurobiol Dis 2024; 199:106589. [PMID: 38969232 DOI: 10.1016/j.nbd.2024.106589] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 06/19/2024] [Accepted: 07/02/2024] [Indexed: 07/07/2024] Open
Abstract
BACKGROUND Despite the large body of work on local field potentials (LFPs), a measure of oscillatory activity in patients with Parkinson's disease (PD), the longitudinal evolution of LFPs is less explored. OBJECTIVE To determine LFP fluctuations collected in clinical settings in patients with PD and STN deep brain stimulation (DBS). METHODS Twenty-two STN-DBS patients (age: 67.6 ± 8.3 years; 9 females; disease duration: 10.3 ± 4.5 years) completed bilateral LFP recordings over three visits in the OFF-stimulation setting. Peak and band power measures were calculated from each recording. RESULTS After bilateral LFP recordings, at least one peak was detected in 18 (81.8%), 20 (90.9%), and 22 (100%) patients at visit 1, 2, and 3, respectively. No significant differences were seen in primary peak amplitude (F = 2.91, p = 0.060) over time. Amplitude of the second largest peak (F = 5.49, p = 0.006) and low-beta (F = 6.89, p = 0.002), high-beta (F = 13.23, p < 0.001), and gamma (F = 12.71, p < 0.001) band power demonstrated a significant effect of time. Post hoc comparisons determined low-beta power (Visit 1-Visit 2: t = 3.59, p = 0.002; Visit 1-Visit 3: t = 2.61, p = 0.031), high-beta (Visit 1-Visit 2: t = 4.64, p < 0.001; Visit 1-Visit 3: t = 4.23, p < 0.001) and gamma band power (Visit 1-Visit 2: t = 4.65, p < 0.001; Visit 1-Visit 3: t = 4.00, p < 0.001) were significantly increased from visit 1 recordings to both follow-up visits. CONCLUSION Our results provide substantial evidence that LFP can reliably be detected across multiple real-world clinical visits in patients with STN-DBS for PD. Moreover, it provides insights on the evolution of these LFPs.
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Affiliation(s)
- Alfonso Fasano
- Edmond J. Safra Program in Parkinson's Disease, Morton and Gloria Shulman Movement Disorders Clinic, Toronto Western Hospital, UHN, Toronto, Canada; Division of Neurology, University of Toronto, Toronto, Canada; Krembil Brain Institute, University Health Network, Toronto, Canada; Center for Advancing Neurotechnological Innovation to Application, Toronto, Canada.
| | - Hideo Mure
- Center for Neuromodulation, Department of Neurosurgery, Kurashiki Heisei Hospital, Kurashiki, Japan
| | - Genko Oyama
- Department of Neurology, Faculty of Medicine, Juntendo University, Tokyo, Japan
| | - Nagako Murase
- Department of Neurology, National Hospital Organization Nara Medical Center, Nara, Japan
| | - Thomas Witt
- Department of Neurosurgery, Indiana University Medical Center, Indianapolis, IN, USA
| | - Yoshinori Higuchi
- Department of Neurological Surgery, Graduate School of Medicine, Chiba University Hospital, Chiba, Japan
| | - Alexa Singer
- Brain Modulation Business, Neuromodulation Operating Unit, Medtronic PLC, Minneapolis, MN, USA
| | - Claudia Sannelli
- Brain Modulation Business, Neuromodulation Operating Unit, Medtronic PLC, Minneapolis, MN, USA
| | - Nathan Morelli
- Brain Modulation Business, Neuromodulation Operating Unit, Medtronic PLC, Minneapolis, MN, USA
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Bocci T, Ferrara R, Albizzati T, Averna A, Guidetti M, Marceglia S, Priori A. Asymmetries of the subthalamic activity in Parkinson's disease: phase-amplitude coupling among local field potentials. Brain Commun 2024; 6:fcae201. [PMID: 38894949 PMCID: PMC11184348 DOI: 10.1093/braincomms/fcae201] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2023] [Revised: 01/22/2024] [Accepted: 06/07/2024] [Indexed: 06/21/2024] Open
Abstract
The role of brain asymmetries of dopaminergic neurons in motor symptoms of Parkinson's disease is still undefined. Local field recordings from the subthalamic nucleus revealed some neurophysiological biomarkers of the disease: increased beta activity, increased low-frequency activity and high-frequency oscillations. Phase-amplitude coupling coordinates the timing of neuronal activity and allows determining the mechanism for communication within distinct regions of the brain. In this study, we discuss the use of phase-amplitude coupling to assess the differences between the two hemispheres in a cohort of 24 patients with Parkinson's disease before and after levodopa administration. Subthalamic low- (12-20 Hz) and high-beta (20-30 Hz) oscillations were compared with low- (30-45 Hz), medium- (70-100 Hz) and high-frequency (260-360 Hz) bands. We found a significant beta-phase-amplitude coupling asymmetry between left and right and an opposite-side-dependent effect of the pharmacological treatment, which is associated with the reduction of motor symptoms. In particular, high coupling between high frequencies and high-beta oscillations was found during the OFF condition (P < 0.01) and a low coupling during the ON state (P < 0.0001) when the right subthalamus was assessed; exactly the opposite happened when the left subthalamus was considered in the analysis, showing a lower coupling between high frequencies and high-beta oscillations during the OFF condition (P < 0.01), followed by a higher one during the ON state (P < 0.01). Interestingly, these asymmetries are independent of the motor onset side, either left or right. These findings have important implications for neural signals that may be used to trigger adaptive deep brain stimulation in Parkinson's and could provide more exhaustive insights into subthalamic dynamics.
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Affiliation(s)
- Tommaso Bocci
- ‘Aldo Ravelli’ Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
- III Neurology Clinic, ASST-Santi Paolo e Carlo University Hospital, 20142 Milan, Italy
| | - Rosanna Ferrara
- ‘Aldo Ravelli’ Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
| | - Tommaso Albizzati
- Department of Engineering and Architecture, University of Trieste, Trieste, 34127 Friuli-Venezia Giulia, Italy
| | - Alberto Averna
- Department of Neurology, Bern University Hospital and University of Bern, 3010 Bern, Switzerland
| | - Matteo Guidetti
- ‘Aldo Ravelli’ Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
| | - Sara Marceglia
- Department of Engineering and Architecture, University of Trieste, Trieste, 34127 Friuli-Venezia Giulia, Italy
- Newronika S.r.l., 20093 Cologno Monzese, Italy
| | - Alberto Priori
- ‘Aldo Ravelli’ Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
- III Neurology Clinic, ASST-Santi Paolo e Carlo University Hospital, 20142 Milan, Italy
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Singh H, Sawal N, Gupta VK, Jha R, Stamm M, Arjun S, Gupta V, Rolston JD. Increased electrode impedance as an indicator for early detection of deep brain stimulation (DBS) hardware Infection: Clinical experience and in vitro study. J Clin Neurosci 2024; 120:76-81. [PMID: 38211444 DOI: 10.1016/j.jocn.2024.01.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2023] [Revised: 12/23/2023] [Accepted: 01/04/2024] [Indexed: 01/13/2024]
Abstract
BACKGROUND When deep brain stimulation (DBS) infections are identified, they are often too advanced to treat without complete hardware removal. New objective markers to promptly identify DBS infections are needed. We present a patient with GPi (globus pallidus interna) DBS for dystonia, where the electrode impedance unexpectedly increased 3-months post-operatively, followed by serologic and hematologic markers of inflammation at 6-months, prompting explantation surgery. We recreated these conditions in a laboratory environment to analyze the pattern of changing of electrical impedance across the contacts of a DBS lead following Staphylococcus biofilm formation. METHODS A stainless-steel culture chamber containing 1 % brain heart infusion agar was used. A DBS electrode was dipped in peptone water containing a strain of S. aureus and subsequently introduced into the chamber. The apparatus was incubated at 37 °C for 6 days. Impedance was measured at 24hr intervals. A control experiment without S. Aureus inoculation was used to determine changes in impedance over a period of 6-days. RESULTS The mean monopolar impedance on day-1 was 751.8 ± 23.8 Ω and on day-3 was 1004.8 ± 68.7 Ω, a 33.7 % rise (p = 0.007). A faint biofilm formation could be seen around the DBS lead by day-2 and florid growth by day-3. After addition of the linezolid solution, a 15.9 % decrease in monopolar impedance was observed from day 3-6 (p = 0.003). CONCLUSION This study gives insight into impedance trends following a hardware infection in DBS. Increased impedance outside expected norms may be valuable for early prediction of infection. Furthermore, timely management using antibiotics might reduce the frequency of infection-related explant surgeries.
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Affiliation(s)
- Hargunbir Singh
- Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, United States; Harvard Medical School, Harvard University, Boston, MA, United States.
| | - Nishit Sawal
- Department of Medicine, Government Medical College and Hospital, Chandigarh, India
| | - Vipin K Gupta
- Department of Neurosurgery, Government Medical College and Hospital, Chandigarh, India
| | - Rohan Jha
- Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, United States; Harvard Medical School, Harvard University, Boston, MA, United States
| | - Michaela Stamm
- Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, United States; Harvard Medical School, Harvard University, Boston, MA, United States
| | - Shivani Arjun
- Department of Medicine, Government Medical College and Hospital, Chandigarh, India
| | - Varsha Gupta
- Department of Microbiology, Government Medical College and Hospital, Chandigarh, India
| | - John D Rolston
- Department of Neurosurgery, Brigham and Women's Hospital, Boston, MA, United States; Harvard Medical School, Harvard University, Boston, MA, United States
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Hill ME, Johnson LA, Wang J, Sanabria DE, Patriat R, Cooper SE, Park MC, Harel N, Vitek JL, Aman JE. Paradoxical Modulation of STN β-Band Activity with Medication Compared to Deep Brain Stimulation. Mov Disord 2024; 39:192-197. [PMID: 37888906 PMCID: PMC10843006 DOI: 10.1002/mds.29634] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 09/20/2023] [Accepted: 10/04/2023] [Indexed: 10/28/2023] Open
Abstract
BACKGROUND Excessive subthalamic nucleus (STN) β-band (13-35 Hz) synchronized oscillations has garnered interest as a biomarker for characterizing disease state and developing adaptive stimulation systems for Parkinson's disease (PD). OBJECTIVES To report on a patient with abnormal treatment-responsive modulation in the β-band. METHODS We examined STN local field potentials from an externalized deep brain stimulation (DBS) lead while assessing PD motor signs in four conditions (OFF, MEDS, DBS, and MEDS+DBS). RESULTS The patient presented here exhibited a paradoxical increase in β power following administration of levodopa and pramipexole (MEDS), but an attenuation in β power during DBS and MEDS+DBS despite clinical improvement of 50% or greater under all three therapeutic conditions. CONCLUSIONS This case highlights the need for further study on the role of β oscillations in the pathophysiology of PD and the importance of personalized approaches to the development of β or other biomarker-based DBS closed loop algorithms. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Meghan E. Hill
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
| | - Luke A. Johnson
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
| | - Jing Wang
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
| | | | - Rémi Patriat
- Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | - Scott E. Cooper
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
| | - Michael C. Park
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
- Department of Neurosurgery, University of Minnesota, Minneapolis, MN, USA
| | - Noam Harel
- Department of Radiology, University of Minnesota, Minneapolis, MN, USA
| | - Jerrold L. Vitek
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
| | - Joshua E. Aman
- Department of Neurology, University of Minnesota, Minneapolis, MN, USA
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Avantaggiato F, Farokhniaee A, Bandini A, Palmisano C, Hanafi I, Pezzoli G, Mazzoni A, Isaias IU. Intelligibility of speech in Parkinson's disease relies on anatomically segregated subthalamic beta oscillations. Neurobiol Dis 2023; 185:106239. [PMID: 37499882 DOI: 10.1016/j.nbd.2023.106239] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Revised: 07/16/2023] [Accepted: 07/24/2023] [Indexed: 07/29/2023] Open
Abstract
BACKGROUND Speech impairment is commonly reported in Parkinson's disease and is not consistently improved by available therapies - including deep brain stimulation of the subthalamic nucleus (STN-DBS), which can worsen communication performance in some patients. Improving the outcome of STN-DBS on speech is difficult due to our incomplete understanding of the contribution of the STN to fluent speaking. OBJECTIVE To assess the relationship between subthalamic neural activity and speech production and intelligibility. METHODS We investigated bilateral STN local field potentials (LFPs) in nine parkinsonian patients chronically implanted with DBS during overt reading. LFP spectral features were correlated with clinical scores and measures of speech intelligibility. RESULTS Overt reading was associated with increased beta-low ([1220) Hz) power in the left STN, whereas speech intelligibility correlated positively with beta-high ([2030) Hz) power in the right STN. CONCLUSION We identified separate contributions from frequency and brain lateralization of the STN in the execution of an overt reading motor task and its intelligibility. This subcortical organization could be exploited for new adaptive stimulation strategies capable of identifying the occurrence of speaking behavior and facilitating its functional execution.
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Affiliation(s)
- Federica Avantaggiato
- Department of Neurology, University Hospital of Würzburg and Julius Maximilian University of Würzburg, Josef-Schneider-Straße 11, 97080 Würzburg, Germany.
| | - AmirAli Farokhniaee
- Fondazione Grigioni per il Morbo di Parkinson, Via Gianfranco Zuretti 35, 20125 Milano, Italy.
| | - Andrea Bandini
- The BioRobotics Institute, Department of Excellence in Robotics and AI, Scuola Superiore Sant'Anna, Viale Rinaldo Piaggo 34, Pontedera, Pisa, Italy; KITE Research Institute, Toronto Rehabilitation Institute, University Health Network, Toronto, ON, Canada; Health Science Interdisciplinary Center, Scuola Superiore Sant'Anna, Viale Rinaldo Piaggo 34, Pontedera, Pisa, Italy.
| | - Chiara Palmisano
- Department of Neurology, University Hospital of Würzburg and Julius Maximilian University of Würzburg, Josef-Schneider-Straße 11, 97080 Würzburg, Germany; Parkinson Institute Milan, ASST G. Pini-CTO, via Bignami 1, 20126 Milano, Italy.
| | - Ibrahem Hanafi
- Department of Neurology, University Hospital of Würzburg and Julius Maximilian University of Würzburg, Josef-Schneider-Straße 11, 97080 Würzburg, Germany.
| | - Gianni Pezzoli
- Fondazione Grigioni per il Morbo di Parkinson, Via Gianfranco Zuretti 35, 20125 Milano, Italy; Parkinson Institute Milan, ASST G. Pini-CTO, via Bignami 1, 20126 Milano, Italy.
| | - Alberto Mazzoni
- Health Science Interdisciplinary Center, Scuola Superiore Sant'Anna, Viale Rinaldo Piaggo 34, Pontedera, Pisa, Italy.
| | - Ioannis U Isaias
- Department of Neurology, University Hospital of Würzburg and Julius Maximilian University of Würzburg, Josef-Schneider-Straße 11, 97080 Würzburg, Germany; Parkinson Institute Milan, ASST G. Pini-CTO, via Bignami 1, 20126 Milano, Italy.
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Muhammad N, Sonkusare S, Ding Q, Wang L, Mandali A, Zhao YJ, Sun B, Li D, Voon V. Time-locked acute alpha-frequency stimulation of subthalamic nuclei during the evaluation of emotional stimuli and its effect on power modulation. Front Hum Neurosci 2023; 17:1181635. [PMID: 37576474 PMCID: PMC10415014 DOI: 10.3389/fnhum.2023.1181635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 05/23/2023] [Indexed: 08/15/2023] Open
Abstract
Introduction Deep brain stimulation (DBS) studies in Parkinson's Disease (PD) targeting the subthalamic nucleus (STN) have characterized its spectral properties across cognitive processes. In emotional evaluation tasks, specific alpha frequency (8-12 Hz) event-related de-synchronization (ERD) (reduced power) has been demonstrated. The time-locked stimulation of STN relative to stimuli onset has shown subjective positive valence shifts with 10 Hz but not with 130 Hz. However, neurophysiological effects of stimulation on power modulation have not been investigated. We aim to investigate effects of acute stimulation of the right STN on concurrent power modulation in the contralateral STN and frontal scalp EEG. From our previous study, we had a strong a priori hypothesis that negative imagery without stimulation would be associated with alpha ERD; negative imagery with 130 Hz stimulation would be also associated with alpha ERD given the lack of its effect on subjective valence ratings; negative imagery with 10 Hz stimulation was to be associated with enhanced alpha power given the shift in behavioral valence ratings. Methods Twenty-four subjects with STN DBS underwent emotional picture-viewing tasks comprising neutral and negative pictures. In a subset of these subjects, the negative images were associated with time-locked acute stimulation at either 10 or 130 Hz. Power of signals was estimated relative to the baseline and subjected to non-parametric statistical testing. Results As hypothesized, in 130 Hz stimulation condition, we show a decrease in alpha power to negative vs. neutral images irrespective of stimulation. In contrast, this alpha power decrease was no longer evident in the negative 10 Hz stimulation condition consistent with a predicted increase in alpha power. Greater beta power in the 10 Hz stimulation condition along with correlations between beta power across the 10 Hz stimulation and unstimulated conditions suggest physiological and cognitive generalization effects. Conclusion Acute alpha-specific frequency stimulation presumably was associated with a loss of this expected decrease or desynchronization in alpha power to negative images suggesting the capacity to facilitate the synchronization of alpha and enhance power. Acute time-locked stimulation has the potential to provide causal insights into the spectral frequencies and temporal dynamics of emotional processing.
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Affiliation(s)
- Naeem Muhammad
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
| | - Saurabh Sonkusare
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Qiong Ding
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Linbin Wang
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
- Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Alekhya Mandali
- Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
| | - Yi Jie Zhao
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
- Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Fudan University, Shanghai, China
| | - Bomin Sun
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Dianyou Li
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
| | - Valerie Voon
- Department of Neurosurgery, Centre for Functional Neurosurgery, Ruijin Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China
- Department of Psychiatry, University of Cambridge, Cambridge, United Kingdom
- Institute of Science and Technology for Brain-Inspired Intelligence, Fudan University, Shanghai, China
- Key Laboratory of Computational Neuroscience and Brain-Inspired Intelligence, Fudan University, Shanghai, China
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Prenassi M, Borellini L, Bocci T, Scola E, Barbieri S, Priori A, Ferrucci R, Cogiamanian F, Locatelli M, Rampini P, Vergari M, Pastore S, Datola B, Marceglia S. Peri-lead edema and local field potential correlation in post-surgery subthalamic nucleus deep brain stimulation patients. Front Hum Neurosci 2022; 16:950434. [PMID: 36158622 PMCID: PMC9495298 DOI: 10.3389/fnhum.2022.950434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Accepted: 07/26/2022] [Indexed: 12/01/2022] Open
Abstract
Implanting deep brain stimulation (DBS) electrodes in patients with Parkinson’s disease often results in the appearance of a non-infectious, delayed-onset edema that disappears over time. However, the time window between the DBS electrode and DBS stimulating device implant is often used to record local field potentials (LFPs) which are used both to better understand basal ganglia pathophysiology and to improve DBS therapy. In this work, we investigated whether the presence of post-surgery edema correlates with the quality of LFP recordings in eight patients with advanced Parkinson’s disease implanted with subthalamic DBS electrodes. The magnetic resonance scans of the brain after 8.5 ± 1.5 days from the implantation surgery were segmented and the peri-electrode edema volume was calculated for both brain hemispheres. We found a correlation (ρ = −0.81, p < 0.0218, Spearman’s correlation coefficient) between left side local field potentials of the low beta band (11–20 Hz) and the edema volume of the same side. No other significant differences between the hemispheres were found. Despite the limited sample size, our results suggest that the effect on LFPs may be related to the edema localization, thus indicating a mechanism involving brain networks instead of a simple change in the electrode-tissue interface.
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Affiliation(s)
- Marco Prenassi
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
- Department of Engineering and Architecture, Università degli Studi di Trieste, Trieste, Italy
- *Correspondence: Marco Prenassi
| | - Linda Borellini
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Tommaso Bocci
- “Aldo Ravelli” Research Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan Medical School, Milan, Italy
| | - Elisa Scola
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
- Neuroradiology Unit, Department of Radiology, Careggi University Hospital, Florence, Italy
| | - Sergio Barbieri
- Department of Engineering and Architecture, Università degli Studi di Trieste, Trieste, Italy
| | - Alberto Priori
- “Aldo Ravelli” Research Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan Medical School, Milan, Italy
| | - Roberta Ferrucci
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
- “Aldo Ravelli” Research Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan Medical School, Milan, Italy
| | | | - Marco Locatelli
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
- “Aldo Ravelli” Research Center for Neurotechnology and Experimental Brain Therapeutics, Department of Health Sciences, University of Milan Medical School, Milan, Italy
- Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Paolo Rampini
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Maurizio Vergari
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
| | - Stefano Pastore
- Department of Engineering and Architecture, Università degli Studi di Trieste, Trieste, Italy
| | - Bianca Datola
- Department of Engineering and Architecture, Università degli Studi di Trieste, Trieste, Italy
| | - Sara Marceglia
- Fondazione IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milano, Italy
- Department of Engineering and Architecture, Università degli Studi di Trieste, Trieste, Italy
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8
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Darcy N, Lofredi R, Al-Fatly B, Neumann WJ, Hübl J, Brücke C, Krause P, Schneider GH, Kühn A. Spectral and spatial distribution of subthalamic beta peak activity in Parkinson's disease patients. Exp Neurol 2022; 356:114150. [PMID: 35732220 DOI: 10.1016/j.expneurol.2022.114150] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2022] [Revised: 05/27/2022] [Accepted: 06/15/2022] [Indexed: 11/17/2022]
Abstract
Current efforts to optimize subthalamic deep brain stimulation in Parkinson's disease patients aim to harness local oscillatory activity in the beta frequency range (13-35 Hz) as a feedback-signal for demand-based adaptive stimulation paradigms. A high prevalence of beta peak activity is prerequisite for this approach to become routine clinical practice. In a large dataset of postoperative rest recordings from 106 patients we quantified occurrence and identified determinants of spectral peaks in the alpha, low and high beta bands. At least one peak in beta band occurred in 92% of patients and 84% of hemispheres off medication, irrespective of demographic parameters, clinical subtype or motor symptom severity. Distance to previously described clinical sweet spot was significantly related both to beta peak occurrence and to spectral power (rho -0.21, p 0.006), particularly in the high beta band. Electrophysiological landscapes of our cohort's dataset in normalised space showed divergent heatmaps for alpha and beta but found similar regions for low and high beta frequency bands. We discuss potential ramifications for clinicians' programming decisions. In summary, this report provides robust evidence that spectral peaks in beta frequency range can be detected in the vast majority of Parkinsonian subthalamic nuclei, increasing confidence in the broad applicability of beta-guided deep brain stimulation.
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Affiliation(s)
- Natasha Darcy
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany; Berlin Institute of Health (BIH), Berlin, Germany.
| | - Roxanne Lofredi
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany; Berlin Institute of Health (BIH), Berlin, Germany
| | - Bassam Al-Fatly
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Wolf-Julian Neumann
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany; Bernstein Center for Computational Neuroscience, Humboldt-Universität, Berlin, Germany
| | - Julius Hübl
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Christof Brücke
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Patricia Krause
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Gerd-Helge Schneider
- Department of Neurosurgery, Charité - Universitätsmedizin Berlin, Berlin, Germany
| | - Andrea Kühn
- Department of Neurology, Charité - Universitätsmedizin Berlin, Berlin, Germany; Bernstein Center for Computational Neuroscience, Humboldt-Universität, Berlin, Germany; NeuroCure, Exzellenzcluster, Charité - Universitätsmedizin Berlin, Berlin, Germany; DZNE, German center for neurodegenerative diseases, Berlin, Germany; Berlin School of Mind and Brain, Humboldt-Universität zu Berlin, Germany
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9
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Averna A, Marceglia S, Arlotti M, Locatelli M, Rampini P, Priori A, Bocci T. Influence of inter-electrode distance on subthalamic nucleus local field potential recordings in Parkinson's disease. Clin Neurophysiol 2021; 133:29-38. [PMID: 34794045 DOI: 10.1016/j.clinph.2021.10.003] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2021] [Revised: 09/24/2021] [Accepted: 10/05/2021] [Indexed: 11/03/2022]
Abstract
OBJECTIVES To evaluate spectra and their correlations with clinical symptoms of local field potentials (LFP) acquired from wide- and close-spaced contacts (i.e. between contacts 0-3 or LFP03, and contacts 1-2 or LFP12 respectively) on the same DBS electrode within the subthalamus (STN) in Parkinson's disease (PD), before and after levodopa administration. METHODS LFP12 and LFP03 were recorded from 20 PD patients. We evaluated oscillatory power, local and switched phase-amplitude coupling (l- and Sw-PAC) and correlation with motor symptoms (UPDRSIII). RESULTS Before levodopa, both LFP03 and LFP12 power in the α band inversely correlated with UPDRSIII. Differences between contacts were found in the low-frequency bands power. After levodopa, differences in UPDRSIII were associated to changes in LFP03 low-β and LFP12 HFO (high frequency oscillations, 250-350 Hz) power, while a modulation of the low-β power and an increased β-LFO (low frequency oscillations, 15-45 Hz) PAC was found only for LFP12. CONCLUSION This study reveals differences in spectral pattern between LFP12 and LFP03 before and after levodopa administration, as well as different correlations with PD motor symptoms. SIGNIFICANCE Differences between LFP12 and LFP03 may offer an opportunity for optimizing adaptive deep brain stimulation (aDBS) protocols for PD. LFP12 can be used to detect β-HFO coupling and β power (i.e. bradykinesia), while LFP03 are optimal for low frequency oscillations (dyskinesias).
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Affiliation(s)
- Alberto Averna
- Aldo Ravelli" Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy
| | - Sara Marceglia
- Department of Engineering and Architecture, University of Trieste, 34127 Trieste, Italy
| | | | - Marco Locatelli
- Aldo Ravelli" Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy; Department of Neurosurgery, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Paolo Rampini
- Department of Neurosurgery, Fondazione IRCCS Cà Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Alberto Priori
- Aldo Ravelli" Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy; Clinical Neurology Unit I, San Paolo University Hospital, ASST Santi Paolo e Carlo and Department of Health Sciences, 20142 Milan, Italy
| | - Tommaso Bocci
- Aldo Ravelli" Research Center for Neurotechnology and Experimental Neurotherapeutics, Department of Health Sciences, University of Milan, 20142 Milan, Italy; Clinical Neurology Unit I, San Paolo University Hospital, ASST Santi Paolo e Carlo and Department of Health Sciences, 20142 Milan, Italy..
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10
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Muthuraman M, Palotai M, Jávor-Duray B, Kelemen A, Koirala N, Halász L, Erőss L, Fekete G, Bognár L, Deuschl G, Tamás G. Frequency-specific network activity predicts bradykinesia severity in Parkinson's disease. Neuroimage Clin 2021; 32:102857. [PMID: 34662779 PMCID: PMC8526781 DOI: 10.1016/j.nicl.2021.102857] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2021] [Revised: 09/15/2021] [Accepted: 10/12/2021] [Indexed: 11/18/2022]
Abstract
OBJECTIVE Bradykinesia has been associated with beta and gamma band interactions in the basal ganglia-thalamo-cortical circuit in Parkinson's disease. In this present cross-sectional study, we aimed to search for neural networks with electroencephalography whose frequency-specific actions may predict bradykinesia. METHODS Twenty Parkinsonian patients treated with bilateral subthalamic stimulation were first prescreened while we selected four levels of contralateral stimulation (0: OFF, 1-3: decreasing symptoms to ON state) individually, based on kinematics. In the screening period, we performed 64-channel electroencephalography measurements simultaneously with electromyography and motion detection during a resting state, finger tapping, hand grasping tasks, and pronation-supination of the arm, with the four levels of contralateral stimulation. We analyzed spectral power at the low (13-20 Hz) and high (21-30 Hz) beta frequency bands and low (31-60 Hz) and high (61-100 Hz) gamma frequency bands using the dynamic imaging of coherent sources. Structural equation modelling estimated causal relationships between the slope of changes in network beta and gamma activities and the slope of changes in bradykinesia measures. RESULTS Activity in different subnetworks, including predominantly the primary motor and premotor cortex, the subthalamic nucleus predicted the slopes in amplitude and speed while switching between stimulation levels. These subnetwork dynamics on their preferred frequencies predicted distinct types and parameters of the movement only on the contralateral side. DISCUSSION Concurrent subnetworks affected in bradykinesia and their activity changes in the different frequency bands are specific to the type and parameters of the movement; and the primary motor and premotor cortex are common nodes.
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Affiliation(s)
- Muthuraman Muthuraman
- Movement Disorders, Imaging and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing, Department of Neurology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany
| | - Marcell Palotai
- Department of Neurology, Semmelweis University, Budapest, Hungary
| | | | - Andrea Kelemen
- Department of Neurology, Semmelweis University, Budapest, Hungary
| | - Nabin Koirala
- Movement Disorders, Imaging and Neurostimulation, Biomedical Statistics and Multimodal Signal Processing, Department of Neurology, University Medical Center of the Johannes Gutenberg University, Mainz, Germany; Haskins Laboratories, New Haven, USA
| | - László Halász
- National Institute of Clinical Neurosciences, Budapest, Hungary
| | - Loránd Erőss
- National Institute of Clinical Neurosciences, Budapest, Hungary
| | - Gábor Fekete
- Department of Neurosurgery, University of Debrecen, Debrecen, Hungary
| | - László Bognár
- Department of Neurosurgery, University of Debrecen, Debrecen, Hungary
| | - Günther Deuschl
- Department of Neurology, Christian-Albrechts University, Kiel, Germany
| | - Gertrúd Tamás
- Department of Neurology, Semmelweis University, Budapest, Hungary.
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11
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Eight-hours conventional versus adaptive deep brain stimulation of the subthalamic nucleus in Parkinson's disease. NPJ PARKINSONS DISEASE 2021; 7:88. [PMID: 34584095 PMCID: PMC8478873 DOI: 10.1038/s41531-021-00229-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 07/23/2021] [Indexed: 12/04/2022]
Abstract
This study compares the effects on motor symptoms between conventional deep brain stimulation (cDBS) and closed-loop adaptive deep brain stimulation (aDBS) in patients with Parkinson’s Disease. The aDBS stimulation is controlled by the power in the beta band (12–35 Hz) of local field potentials recorded directly by subthalamic nucleus electrodes. Eight subjects were assessed in two 8-h stimulation sessions (first day, cDBS; second day, aDBS) with regular levodopa intake and during normal daily activities. The Unified Parkinson’s Disease Rating Scale (UPDRS) part III scores, the Rush scale for dyskinesias, and the total electrical energy delivered to the tissues per second (TEEDs) were significantly lower in the aDBS session (relative UPDRS mean, cDBS: 0.46 ± 0.05, aDBS: 0.33 ± 0.04, p = 0.015; UPDRS part III rigidity subset mean, cDBS: 2.9143 ± 0.6551 and aDBS: 2.1429 ± 0.5010, p = 0.034; UPDRS part III standard deviation cDBS: 2.95, aDBS: 2.68; p = 0.047; Rush scale, cDBS 2.79 ± 0.39 versus aDBS 1.57 ± 0.23, p = 0.037; cDBS TEEDs mean: 28.75 ± 3.36 µj s−1, aDBS TEEDs mean: 16.47 ± 3.33, p = 0.032 Wilcoxon’s sign rank test). This work further supports the safety and effectiveness of aDBS stimulation compared to cDBS in a daily session, both in terms of motor performance and TEED to the patient.
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12
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Ali HAM, Abdullah SS, Faraj MK. High impedance analysis in recordings of deep brain stimulation surgery. INTERDISCIPLINARY NEUROSURGERY 2021. [DOI: 10.1016/j.inat.2021.101115] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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13
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Brinda AK, Doyle AM, Blumenfeld M, Krieg J, Alisch JSR, Spencer C, Lecy E, Wilmerding LK, DeNicola A, Johnson LA, Vitek JL, Johnson MD. Longitudinal analysis of local field potentials recorded from directional deep brain stimulation lead implants in the subthalamic nucleus. J Neural Eng 2021; 18:10.1088/1741-2552/abfc1c. [PMID: 33906174 PMCID: PMC8504120 DOI: 10.1088/1741-2552/abfc1c] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Accepted: 04/27/2021] [Indexed: 11/12/2022]
Abstract
Objective.The electrode-tissue interface surrounding a deep brain stimulation (DBS) lead is known to be highly dynamic following implantation, which may have implications on the interpretation of intraoperatively recorded local field potentials (LFPs). We characterized beta-band LFP dynamics following implantation of a directional DBS lead in the sensorimotor subthalamic nucleus (STN), which is a primary target for treating Parkinson's disease.Approach.Directional STN-DBS leads were implanted in four healthy, non-human primates. LFPs were recorded over two weeks and again 1-4 months after implantation. Impedance was measured for two weeks post-implant without stimulation to compare the reactive tissue response to changes in LFP oscillations. Beta-band (12-30 Hz) peak power was calculated from the LFP power spectra using both common average referencing (CAR) and intra-row bipolar referencing (IRBR).Results.Resting-state LFPs in two of four subjects revealed a steady increase of beta power over the initial two weeks post-implant whereas the other two subjects showed variable changes over time. Beta power variance across days was significantly larger in the first two weeks compared to 1-4 months post-implant in all three long-term subjects. Further, spatial maps of beta power several hours after implantation did not correlate with those measured two weeks or 1-4 months post-implant. CAR and IRBR beta power correlated across short- and long-term time points. However, depending on the time period, subjects showed a significant bias towards larger beta power using one referencing scheme over the other. Lastly, electrode-tissue impedance increased over the two weeks post-implant but showed no significant correlation to beta power.Significance.These results suggest that beta power in the STN may undergo significant changes following DBS lead implantation. DBS lead diameter and electrode recording configurations can affect the post-implant interpretation of oscillatory features. Such insights will be important for extrapolating results from intraoperative and externalized LFP recordings.
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Affiliation(s)
- AnneMarie K Brinda
- Department of Biomedical Engineering, University of Minnesota, 7-105 Nils Hasselmo Hall, 312 Church Street SE, Minneapolis, MN 55455, United States of America
| | - Alex M Doyle
- Department of Neuroscience, University of Minnesota, Minneapolis, MN 55455, United States of America
| | - Madeline Blumenfeld
- Department of Biomedical Engineering, University of Minnesota, 7-105 Nils Hasselmo Hall, 312 Church Street SE, Minneapolis, MN 55455, United States of America
| | - Jordan Krieg
- Department of Biomedical Engineering, University of Minnesota, 7-105 Nils Hasselmo Hall, 312 Church Street SE, Minneapolis, MN 55455, United States of America
| | - Joseph S R Alisch
- Department of Biomedical Engineering, University of Minnesota, 7-105 Nils Hasselmo Hall, 312 Church Street SE, Minneapolis, MN 55455, United States of America
| | - Chelsea Spencer
- Department of Biomedical Engineering, University of Minnesota, 7-105 Nils Hasselmo Hall, 312 Church Street SE, Minneapolis, MN 55455, United States of America
| | - Emily Lecy
- Department of Biomedical Engineering, University of Minnesota, 7-105 Nils Hasselmo Hall, 312 Church Street SE, Minneapolis, MN 55455, United States of America
| | - Lucius K Wilmerding
- Department of Biomedical Engineering, University of Minnesota, 7-105 Nils Hasselmo Hall, 312 Church Street SE, Minneapolis, MN 55455, United States of America
| | - Adele DeNicola
- Department of Neurology, University of Minnesota, Minneapolis, MN 55455, United States of America
| | - Luke A Johnson
- Department of Neurology, University of Minnesota, Minneapolis, MN 55455, United States of America
| | - Jerrold L Vitek
- Department of Neurology, University of Minnesota, Minneapolis, MN 55455, United States of America
| | - Matthew D Johnson
- Department of Biomedical Engineering, University of Minnesota, 7-105 Nils Hasselmo Hall, 312 Church Street SE, Minneapolis, MN 55455, United States of America
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14
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Evers J, Lowery M. The Active Electrode in the Living Brain: The Response of the Brain Parenchyma to Chronically Implanted Deep Brain Stimulation Electrodes. Oper Neurosurg (Hagerstown) 2021; 20:131-140. [PMID: 33074305 DOI: 10.1093/ons/opaa326] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 08/10/2020] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Deep brain stimulation is an established symptomatic surgical therapy for Parkinson disease, essential tremor, and a number of other movement and neuropsychiatric disorders. The well-established foreign body response around implanted electrodes is marked by gliosis, neuroinflammation, and neurodegeneration. However, how this response changes with the application of chronic stimulation is less well-understood. OBJECTIVE To integrate the most recent evidence from basic science, patient, and postmortem studies on the effect of such an "active" electrode on the parenchyma of the living brain. METHODS A thorough and in-part systematic literature review identified 49 papers. RESULTS Increased electrode-tissue impedance is consistently observed in the weeks following electrode implantation, stabilizing at approximately 3 to 6 mo. Lower impedance values are observed around stimulated implanted electrodes when compared with unstimulated electrodes. A temporary reduction in impedance has also been observed in response to stimulation in nonhuman primates. Postmortem studies from patients confirm the presence of a fibrous sheath, astrocytosis, neuronal loss, and neuroinflammation in the immediate vicinity of the electrode. When comparing stimulated and unstimulated electrodes directly, there is some evidence across animal and patient studies of altered neurodegeneration and neuroinflammation around stimulated electrodes. CONCLUSION Establishing how stimulation influences the electrical and histological properties of the surrounding tissue is critical in understanding how these factors contribute to DBS efficacy, and in controlling symptoms and side effects. Understanding these complex issues will aid in the development of future neuromodulation systems that are optimized for the tissue environment and required stimulation protocols.
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Affiliation(s)
- Judith Evers
- School of Electrical and Electronic Engineering, University College Dublin, Dublin, Ireland.,CÚRAM SFI Research Centre for Medical Devices, National University of Ireland Galway, Galway, Ireland
| | - Madeleine Lowery
- School of Electrical and Electronic Engineering, University College Dublin, Dublin, Ireland.,CÚRAM SFI Research Centre for Medical Devices, National University of Ireland Galway, Galway, Ireland
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15
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Mapping of subthalamic nucleus using microelectrode recordings during deep brain stimulation. Sci Rep 2020; 10:19241. [PMID: 33159098 PMCID: PMC7648837 DOI: 10.1038/s41598-020-74196-5] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2020] [Accepted: 09/23/2020] [Indexed: 11/17/2022] Open
Abstract
Alongside stereotactic magnetic resonance imaging, microelectrode recording (MER) is frequently used during the deep brain stimulation (DBS) surgery for optimal target localization. The aim of this study is to optimize subthalamic nucleus (STN) mapping using MER analytical patterns. 16 patients underwent bilateral STN-DBS. MER was performed simultaneously for 5 microelectrodes in a setting of Ben’s-gun pattern in awake patients. Using spikes and background activity several different parameters and their spectral estimates in various frequency bands including low frequency (2–7 Hz), Alpha (8–12 Hz), Beta (sub-divided as Low_Beta (13–20 Hz) and High_Beta (21–30 Hz)) and Gamma (31 to 49 Hz) were computed. The optimal STN lead placement with the most optimal clinical effect/side-effect ratio accorded to the maximum spike rate in 85% of the implantation. Mean amplitude of background activity in the low beta frequency range was corresponding to right depth in 85% and right location in 94% of the implantation respectively. MER can be used for STN mapping and intraoperative decisions for the implantation of DBS electrode leads with a high accuracy. Spiking and background activity in the beta range are the most promising independent parameters for the delimitation of the proper anatomical site.
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16
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Wu YH, Ou-Yang YH, Chen CC, Lee CY, Wu CY, Ker MD. Miniaturized Intracerebral Potential Recorder for Long-Term Local Field Potential of Deep Brain Signals. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2020; 2020:5188-5191. [PMID: 33019154 DOI: 10.1109/embc44109.2020.9175384] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
A miniaturized intracerebral potential recorder for long-term local field potential (LFP) of deep brain signals is proposed. LFP can be recorded by deep brain electrodes. The abnormal beta-band oscillation of LFP in subthalamic nucleus and internal globus pallidus in patients with Parkinson's disease (PD) are associated with the severity of the symptoms. The LFP signal from patients who have been implanted with deep brain electrode can be monitored by our system for at least 24 hours in real time. Graphical user interface has also been developed for use by medical personnel. Imitation experiments and in vivo experiments were performed to successfully verify that our system can measure LFP signals. With 24-hour intracerebral signals, researchers can analyze what is happened in the brain in daily life. In the future, more effective PD treatment can be developed, such as intelligent closed-loop deep brain stimulation.
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17
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Parker T, Huang Y, Gong C, Chen Y, Wang S, Green A, Aziz T, Li L. Pain-Induced Beta Activity in the Subthalamic Nucleus of Parkinson’s Disease. Stereotact Funct Neurosurg 2020; 98:193-199. [DOI: 10.1159/000507032] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2019] [Accepted: 02/27/2020] [Indexed: 11/19/2022]
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18
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Lee CY, Wu T, Chang CW, Lim SN, Cheng MY, Lee ST. Electrical cortical stimulation for treatment of intractable epilepsy originating from eloquent cortex: surgical accuracy and clinical efficacy. Acta Neurochir (Wien) 2020; 162:261-269. [PMID: 31781997 DOI: 10.1007/s00701-019-04137-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 11/04/2019] [Indexed: 11/25/2022]
Abstract
BACKGROUND Electrical cortical stimulation is shown effective in treating patients with drug-resistant epilepsy. We demonstrated how detailed procedures of pre- and intra-operative planning of cortical stimulation implantation may influence the results of seizure reduction rate. METHODS To confirm the precision of subdural grids covering the epileptogenic foci in the eloquent regions, pre- and intra-operative video-electroencephalography (VEEG) were performed in patients with drug-resistant epilepsy during a 4-day 24-h monitoring. The localization of the grid was determined via 3D reconstruction imaging of subdural electrodes co-registered onto the patient's cortex. A final quadripolar lead in cyclic stimulation mode was then placed and secured on the target cortex area. Post-operative 3D CT ensured the accurate location of stimulation lead without any misplacement. Bipolar cyclic stimulation and post-implantation VEEG were performed for 7 days. Patients were discharged and followed up regularly for parameters adjustment and recording of seizure outcomes. RESULTS Eight patients received chronic cortical stimulation implantations between February 2003 and December 2017. The mean age of these patients was 21.1 years old and the average post-operative follow-up was 77.3 months. Comparisons of their seizure frequency at baseline and during the postoperative period revealed a mean reduction in seizures of 60.4% at the first year and 65.6% at the second year. CONCLUSIONS Pre-surgical planning enhanced the accuracy of electrode placement and led to a favorable seizure reduction rate. Our report confirms that electrical cortical stimulation with detailed implantation procedures is safe and effective for patients with drug-resistant epilepsy originating from eloquent cortex.
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Affiliation(s)
- Ching-Yi Lee
- Department of Neurosurgery, Chang Gung Memorial Hospital Linkou Medical Center and Chang Gung University College of Medicine, Taoyuan, Taiwan.
- Department of Neurosurgery, Chang Gung Memorial Hospital, 5, Fu-Shing Street, 333 Kweishan, Taoyuan, Taiwan.
| | - Tony Wu
- Section of Epilepsy, Department of Neurology, Chang Gung Memorial Hospital Linkou Medical Center and Chang Gung University College of Medicine, Taoyuan, Taiwan
| | - Chun-Wei Chang
- Section of Epilepsy, Department of Neurology, Chang Gung Memorial Hospital Linkou Medical Center and Chang Gung University College of Medicine, Taoyuan, Taiwan
| | - Siew-Na Lim
- Section of Epilepsy, Department of Neurology, Chang Gung Memorial Hospital Linkou Medical Center and Chang Gung University College of Medicine, Taoyuan, Taiwan
| | - Mei-Yun Cheng
- Section of Epilepsy, Department of Neurology, Chang Gung Memorial Hospital Linkou Medical Center and Chang Gung University College of Medicine, Taoyuan, Taiwan
| | - Shih-Tseng Lee
- Department of Neurosurgery, Chang Gung Memorial Hospital Linkou Medical Center and Chang Gung University College of Medicine, Taoyuan, Taiwan
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Castano-Candamil S, Piroth T, Reinacher P, Sajonz B, Coenen VA, Tangermann M. An Easy-to-Use and Fast Assessment of Patient-Specific DBS-Induced Changes in Hand Motor Control in Parkinson's Disease. IEEE Trans Neural Syst Rehabil Eng 2019; 27:2155-2163. [PMID: 31536010 DOI: 10.1109/tnsre.2019.2941453] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
For Parkinson's disease (PD), efficient and fast monitoring of fine motor function is fundamental for capturing transient phenomena induced by deep brain stimulation (DBS), thus, enabling a fast and accurate tuning of stimulation parameters. Tuning of DBS parameters is important for obtaining a patient-specific optimal clinical effect and to regularly compensate for disease progress. We propose a fine motor function assessment framework for capturing transient DBS-induced changes. The main goals are to obtain a fast, repeatable, objective, robust, and DBS-sensitive motor-score, in addition to a high-dimensional characterization of motor components by means of an interpretable data-driven model. To achieve this, we combine a hand motor-task, termed the copy-draw test, with a linear model for analyzing features extracted from the proposed task. The approach was tested with four patients totaling eight sessions analyzed. Our approach delivers a motor-score that is sensitive to DBS-induced changes in motor function. It can be applied repeatedly within seconds. The interpretability of the underlying machine learning model provides a direct overview of the feature relevance. This analysis allows to detect and characterize single movement components that are sensitive to DBS. The proposed assessment framework is an useful tool to push forward the data-driven identification of PD-relevant neural markers. Consequent to this end, the source code of the paradigm is made publicly available.
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20
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Ozturk M, Abosch A, Francis D, Wu J, Jimenez‐Shahed J, Ince NF. Distinct Subthalamic Coupling in the ON State Describes Motor Performance in Parkinson's Disease. Mov Disord 2019; 35:91-100. [DOI: 10.1002/mds.27800] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 04/20/2019] [Accepted: 06/27/2019] [Indexed: 11/06/2022] Open
Affiliation(s)
- Musa Ozturk
- Department of Biomedical Engineering University of Houston Houston Texas USA
| | - Aviva Abosch
- Department of Neurosurgery University of Colorado Aurora Colorado USA
| | - David Francis
- Department of Psychology University of Houston Houston Texas USA
| | - Jianping Wu
- Restorative Therapies Group Implantables, Research and Core Technology, Medtronic Minneapolis Minnesota USA
| | | | - Nuri F. Ince
- Department of Biomedical Engineering University of Houston Houston Texas USA
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Ramirez Pasos UE, Steigerwald F, Reich MM, Matthies C, Volkmann J, Reese R. Levodopa Modulates Functional Connectivity in the Upper Beta Band Between Subthalamic Nucleus and Muscle Activity in Tonic and Phasic Motor Activity Patterns in Parkinson's Disease. Front Hum Neurosci 2019; 13:223. [PMID: 31312129 PMCID: PMC6614179 DOI: 10.3389/fnhum.2019.00223] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Accepted: 06/18/2019] [Indexed: 01/10/2023] Open
Abstract
Introduction: Striatal dopamine depletion disrupts basal ganglia function and causes Parkinson's disease (PD). The pathophysiology of the dopamine-dependent relationship between basal ganglia signaling and motor control, however, is not fully understood. We obtained simultaneous recordings of local field potentials (LFPs) from the subthalamic nucleus (STN) and electromyograms (EMGs) in patients with PD to investigate the impact of dopaminergic state and movement on long-range beta functional connectivity between basal ganglia and lower motor neurons. Methods: Eight PD patients were investigated 3 months after implantation of a deep brain stimulation (DBS)-system capable of recording LFPs via chronically-implanted leads (Medtronic, ACTIVA PC+S®). We analyzed STN spectral power and its coherence with EMG in the context of two different movement paradigms (tonic wrist extension vs. alternating wrist extension and flexion) and the effect of levodopa (L-Dopa) intake using an unbiased data-driven approach to determine regions of interest (ROI). Results: Two ROIs capturing prominent coherence within a grand average coherogram were identified. A trend of a dopamine effect was observed for the first ROI (50-150 ms after movement start) with higher STN-EMG coherence in medicated patients. Concerning the second ROI (300-500 ms after movement start), an interaction effect of L-Dopa medication and movement task was observed with higher coherence in the isometric contraction task compared to alternating movements in the medication ON state, a pattern which was reversed in L-Dopa OFF. Discussion: L-Dopa medication may normalize functional connectivity between remote structures of the motor system with increased upper beta coherence reflecting a physiological restriction of the amount of information conveyed between remote structures. This may be necessary to maintain simple movements like isometric contraction. Our study adds dynamic properties to the complex interplay between STN spectral beta power and the nucleus' functional connectivity to remote structures of the motor system as a function of movement and dopaminergic state. This may help to identify markers of neuronal activity relevant for more individualized programming of DBS therapy.
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Affiliation(s)
| | - Frank Steigerwald
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - Martin M Reich
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - Cordula Matthies
- Department of Neurosurgery, University Hospital Würzburg, Würzburg, Germany
| | - Jens Volkmann
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany
| | - René Reese
- Department of Neurology, University Hospital Würzburg, Würzburg, Germany.,Department of Neurology, University of Rostock, Rostock, Germany
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22
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Eleopra R, Rinaldo S, Devigili G, Lettieri C, Mondani M, D'Auria S, Piacentino M, Pilleri M. Brain impedance variation of directional leads implanted in subthalamic nuclei of Parkinsonian patients. Clin Neurophysiol 2019; 130:1562-1569. [PMID: 31301634 DOI: 10.1016/j.clinph.2019.06.001] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2018] [Revised: 06/13/2019] [Accepted: 06/14/2019] [Indexed: 11/29/2022]
Abstract
OBJECTIVE Conventional deep brain stimulation (DBS) systems with ring-shaped leads generate spherical electrical fields. In contrast, novel directional leads use segmented electrodes. Aim of this study was to quantify the impedance variations over time in subjects with the directional Cartesia-Boston® system. METHODS Impedance records, programming settings, and clinical data of 11 consecutive Parkinsonian patients implanted with DBS directional leads in two Italian centers (Udine and Vicenza) were retrospectively evaluated. Data were collected before starting stimulation (in the operating room and at days 5 and 40) and after switching stimulation on at the successive follow-up visits (1, 6 and 12 months). RESULTS Directional leads have significantly higher impedance than ring leads. Stimulated contacts had always lower impedance compared to non-stimulated contacts. Before DBS-on, all contacts had higher impedance in the operating room, with an initial decrease five days post-surgery and a subsequent increase at day 40, more evident for directional contacts. The impedance of directional leads increased post-implantation at 1 and 6 months with a plateau at 12 months. CONCLUSIONS There was a significant difference between the directional and ring leads at baseline (before activation of DBS) and during follow-up (chronic DBS). SIGNIFICANCE Our study reveals new information about the impedance of segmented electrodes that is useful for patient management during the initial test period, as well as during long-term DBS follow-up.
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Affiliation(s)
- Roberto Eleopra
- Neurological Unit I, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy.
| | - Sara Rinaldo
- Neurological Unit I, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Grazia Devigili
- Neurological Unit I, Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy
| | - Christian Lettieri
- Neurological Unit, S. Maria della Misericordia Universital Hospital, Udine, Italy
| | - Massimo Mondani
- Neurosurgical Unit, S. Maria della Misericordia Universital Hospital, Udine, Italy
| | - Stanislao D'Auria
- Neurosurgical Unit, S. Maria della Misericordia Universital Hospital, Udine, Italy
| | | | - Manuela Pilleri
- Neurological Unit, Villa Margherita Hospital, Arcugnano, Vicenza, Italy
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Electrical cortical stimulation for refractory focal epilepsy: A long-term follow-up study. Epilepsy Res 2019; 151:24-30. [DOI: 10.1016/j.eplepsyres.2019.01.003] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Revised: 12/25/2018] [Accepted: 01/06/2019] [Indexed: 11/24/2022]
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24
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Yin Z, Cao Y, Zheng S, Duan J, Zhou D, Xu R, Hong T, Lu G. Persistent adverse effects following different targets and periods after bilateral deep brain stimulation in patients with Parkinson's disease. J Neurol Sci 2018; 393:116-127. [DOI: 10.1016/j.jns.2018.08.016] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Revised: 06/22/2018] [Accepted: 08/14/2018] [Indexed: 02/04/2023]
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Mohammed A, Bayford R, Demosthenous A. Toward adaptive deep brain stimulation in Parkinson's disease: a review. Neurodegener Dis Manag 2018; 8:115-136. [DOI: 10.2217/nmt-2017-0050] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Clinical deep brain stimulation (DBS) is now regarded as the therapeutic intervention of choice at the advanced stages of Parkinson's disease. However, some major challenges of DBS are stimulation induced side effects and limited pacemaker battery life. Side effects and shortening of pacemaker battery life are mainly as a result of continuous stimulation and poor stimulation focus. These drawbacks can be mitigated using adaptive DBS (aDBS) schemes. Side effects resulting from continuous stimulation can be reduced through adaptive control using closed-loop feedback, while those due to poor stimulation focus can be mitigated through spatial adaptation. Other advantages of aDBS include automatic, rather than manual, initial adjustment and programming, and long-term adjustments to maintain stimulation parameters with changes in patient's condition. Both result in improved efficacy. This review focuses on the major areas that are essential in driving technological advances for the various aDBS schemes. Their challenges, prospects and progress so far are analyzed. In addition, important advances and milestones in state-of-the-art aDBS schemes are highlighted – both for closed-loop adaption and spatial adaption. With perspectives and future potentials of DBS provided at the end.
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Affiliation(s)
- Ameer Mohammed
- Department of Electronic & Electrical Engineering, University College London, Torrington Place, London WC1E 7JE, UK
| | - Richard Bayford
- Department of Natural Sciences, Middlesex University, The Burroughs, London NW4 6BT, UK
| | - Andreas Demosthenous
- Department of Electronic & Electrical Engineering, University College London, Torrington Place, London WC1E 7JE, UK
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26
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Sun FT, Arcot Desai S, Tcheng TK, Morrell MJ. Changes in the electrocorticogram after implantation of intracranial electrodes in humans: The implant effect. Clin Neurophysiol 2017; 129:676-686. [PMID: 29233473 DOI: 10.1016/j.clinph.2017.10.036] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Revised: 09/29/2017] [Accepted: 10/22/2017] [Indexed: 11/28/2022]
Abstract
OBJECTIVE Subacute and long-term electrocorticographic (ECoG) changes in ambulatory patients with depth and cortical strip electrodes were evaluated in order to determine the length of the implant effect. METHODS ECoG records were assessed in patients with medically intractable epilepsy who had depth and/or strip leads implanted in order to be treated with brain-responsive stimulation. Changes in total spectral power, band-limited spectral power, and spike rate were assessed. RESULTS 121 patients participating in trials of the RNS® System had a total of 93994 ECoG records analyzed. Significant changes in total spectral power occurred from the first to second months after implantation, involving 55% of all ECoG channels (68% of strip and 47% of depth lead channels). Significant, but less pronounced, changes continued over the 2nd to 5th post-implant months, after which total power became more stable. Similar patterns of changes were observed within frequency bands and spike rate. CONCLUSIONS ECoG spectral power and spike rates are not stable in the first 5 months after implantation, presumably due to neurophysiological and electrode-tissue interface changes. SIGNIFICANCE ECoG data collected in the first 5 months after implantation of intracranial electrodes may not be fully representative of chronic cortical electrophysiology.
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Affiliation(s)
| | | | | | - Martha J Morrell
- NeuroPace, Inc., Mountain View, CA 94043, USA; Department of Neurology and Neurological Sciences, Stanford University, Palo Alto, CA 94305, USA
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27
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Parastarfeizabadi M, Kouzani AZ. Advances in closed-loop deep brain stimulation devices. J Neuroeng Rehabil 2017; 14:79. [PMID: 28800738 PMCID: PMC5553781 DOI: 10.1186/s12984-017-0295-1] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Accepted: 08/04/2017] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Millions of patients around the world are affected by neurological and psychiatric disorders. Deep brain stimulation (DBS) is a device-based therapy that could have fewer side-effects and higher efficiencies in drug-resistant patients compared to other therapeutic options such as pharmacological approaches. Thus far, several efforts have been made to incorporate a feedback loop into DBS devices to make them operate in a closed-loop manner. METHODS This paper presents a comprehensive investigation into the existing research-based and commercial closed-loop DBS devices. It describes a brief history of closed-loop DBS techniques, biomarkers and algorithms used for closing the feedback loop, components of the current research-based and commercial closed-loop DBS devices, and advancements and challenges in this field of research. This review also includes a comparison of the closed-loop DBS devices and provides the future directions of this area of research. RESULTS Although we are in the early stages of the closed-loop DBS approach, there have been fruitful efforts in design and development of closed-loop DBS devices. To date, only one commercial closed-loop DBS device has been manufactured. However, this system does not have an intelligent and patient dependent control algorithm. A closed-loop DBS device requires a control algorithm to learn and optimize the stimulation parameters according to the brain clinical state. CONCLUSIONS The promising clinical effects of open-loop DBS have been demonstrated, indicating DBS as a pioneer technology and treatment option to serve neurological patients. However, like other commercial devices, DBS needs to be automated and modernized.
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Affiliation(s)
| | - Abbas Z. Kouzani
- School of Engineering, Deakin University, Waurn Ponds, VIC 3216 Australia
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28
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Meidahl AC, Tinkhauser G, Herz DM, Cagnan H, Debarros J, Brown P. Adaptive Deep Brain Stimulation for Movement Disorders: The Long Road to Clinical Therapy. Mov Disord 2017; 32:810-819. [PMID: 28597557 PMCID: PMC5482397 DOI: 10.1002/mds.27022] [Citation(s) in RCA: 128] [Impact Index Per Article: 18.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/06/2017] [Accepted: 03/19/2017] [Indexed: 11/07/2022] Open
Abstract
Continuous high-frequency DBS is an established treatment for essential tremor and Parkinson's disease. Current developments focus on trying to widen the therapeutic window of DBS. Adaptive DBS (aDBS), where stimulation is dynamically controlled by feedback from biomarkers of pathological brain circuit activity, is one such development. Relevant biomarkers may be central, such as local field potential activity, or peripheral, such as inertial tremor data. Moreover, stimulation may be directed by the amplitude or the phase (timing) of the biomarker signal. In this review, we evaluate existing aDBS studies as proof-of-principle, discuss their limitations, most of which stem from their acute nature, and propose what is needed to take aDBS into a chronic setting. © 2017 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.
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Affiliation(s)
- Anders Christian Meidahl
- Medical Research Council Brain Network Dynamics Unit at the University of OxfordOxfordUK
- Nuffield Department of Clinical Neurosciences, John Radcliffe HospitalUniversity of OxfordOxfordUK
| | - Gerd Tinkhauser
- Medical Research Council Brain Network Dynamics Unit at the University of OxfordOxfordUK
- Nuffield Department of Clinical Neurosciences, John Radcliffe HospitalUniversity of OxfordOxfordUK
- Department of NeurologyBern University Hospital and University of BernBernSwitzerland
| | - Damian Marc Herz
- Nuffield Department of Clinical Neurosciences, John Radcliffe HospitalUniversity of OxfordOxfordUK
| | - Hayriye Cagnan
- Medical Research Council Brain Network Dynamics Unit at the University of OxfordOxfordUK
- Nuffield Department of Clinical Neurosciences, John Radcliffe HospitalUniversity of OxfordOxfordUK
- Institute of NeurologyUniversity College LondonLondonUK
| | - Jean Debarros
- Medical Research Council Brain Network Dynamics Unit at the University of OxfordOxfordUK
- Nuffield Department of Clinical Neurosciences, John Radcliffe HospitalUniversity of OxfordOxfordUK
| | - Peter Brown
- Medical Research Council Brain Network Dynamics Unit at the University of OxfordOxfordUK
- Nuffield Department of Clinical Neurosciences, John Radcliffe HospitalUniversity of OxfordOxfordUK
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29
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Qian X, Chen Y, Feng Y, Ma B, Hao H, Li L. A platform for long-term monitoring the deep brain rhythms. Biomed Phys Eng Express 2017. [DOI: 10.1088/2057-1976/aa50d6] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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30
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Little S, Beudel M, Zrinzo L, Foltynie T, Limousin P, Hariz M, Neal S, Cheeran B, Cagnan H, Gratwicke J, Aziz TZ, Pogosyan A, Brown P. Bilateral adaptive deep brain stimulation is effective in Parkinson's disease. J Neurol Neurosurg Psychiatry 2016; 87:717-21. [PMID: 26424898 PMCID: PMC4941128 DOI: 10.1136/jnnp-2015-310972] [Citation(s) in RCA: 207] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/02/2015] [Accepted: 08/17/2015] [Indexed: 11/26/2022]
Abstract
INTRODUCTION & OBJECTIVES Adaptive deep brain stimulation (aDBS) uses feedback from brain signals to guide stimulation. A recent acute trial of unilateral aDBS showed that aDBS can lead to substantial improvements in contralateral hemibody Unified Parkinson's Disease Rating Scale (UPDRS) motor scores and may be superior to conventional continuous DBS in Parkinson's disease (PD). We test whether potential benefits are retained with bilateral aDBS and in the face of concurrent medication. METHODS We applied bilateral aDBS in 4 patients with PD undergoing DBS of the subthalamic nucleus. aDBS was delivered bilaterally with independent triggering of stimulation according to the amplitude of β activity at the corresponding electrode. Mean stimulation voltage was 3.0±0.1 volts. Motor assessments consisted of double-blinded video-taped motor UPDRS scores that included both limb and axial features. RESULTS UPDRS scores were 43% (p=0.04; Cohen's d=1.62) better with aDBS than without stimulation. Motor improvement with aDBS occurred despite an average time on stimulation (ToS) of only 45%. Levodopa was well tolerated during aDBS and led to further reductions in ToS. CONCLUSION Bilateral aDBS can improve both axial and limb symptoms and can track the need for stimulation across drug states.
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Affiliation(s)
- Simon Little
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Martijn Beudel
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK Department of Neurology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands
| | - Ludvic Zrinzo
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, London, UK
| | - Thomas Foltynie
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, London, UK
| | - Patricia Limousin
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, London, UK
| | - Marwan Hariz
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, London, UK
| | - Spencer Neal
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, London, UK
| | - Binith Cheeran
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Hayriye Cagnan
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - James Gratwicke
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, London, UK
| | - Tipu Z Aziz
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK Nuffield Department of Surgical Sciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Alex Pogosyan
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK The Medical Research Council Brain Networks Dynamics Unit, University of Oxford, Oxford, UK
| | - Peter Brown
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK The Medical Research Council Brain Networks Dynamics Unit, University of Oxford, Oxford, UK
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Arlotti M, Rosa M, Marceglia S, Barbieri S, Priori A. The adaptive deep brain stimulation challenge. Parkinsonism Relat Disord 2016; 28:12-7. [PMID: 27079257 DOI: 10.1016/j.parkreldis.2016.03.020] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Revised: 03/25/2016] [Accepted: 03/28/2016] [Indexed: 01/17/2023]
Abstract
Sub-optimal clinical outcomes of conventional deep brain stimulation (cDBS) in treating Parkinson's Disease (PD) have boosted the development of new solutions to improve DBS therapy. Adaptive DBS (aDBS), consisting of closed-loop, real-time changing of stimulation parameters according to the patient's clinical state, promises to achieve this goal and is attracting increasing interest in overcoming all of the challenges posed by its development and adoption. In the design, implementation, and application of aDBS, the choice of the control variable and of the control algorithm represents the core challenge. The proposed approaches, in fact, differ in the choice of the control variable and control policy, in the system design and its technological limits, in the patient's target symptom, and in the surgical procedure needed. Here, we review the current proposals for aDBS systems, focusing on the choice of the control variable and its advantages and drawbacks, thus providing a general overview of the possible pathways for the clinical translation of aDBS with its benefits, limitations and unsolved issues.
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Affiliation(s)
- Mattia Arlotti
- Clinical Center for Neurostimulation, Neurotechnology, and Movement Disorders, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Electronics, Computer Science and Systems, University of Bologna, Cesena, Italy
| | - Manuela Rosa
- Clinical Center for Neurostimulation, Neurotechnology, and Movement Disorders, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Sara Marceglia
- Clinical Center for Neurostimulation, Neurotechnology, and Movement Disorders, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Department of Engineering and Architecture, University of Trieste, Trieste, Italy
| | - Sergio Barbieri
- Clinical Center for Neurostimulation, Neurotechnology, and Movement Disorders, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy; Unità di Neurofisiopatologia, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico di Milano, Milan, Italy
| | - Alberto Priori
- Department of Health Sciences, University of Milan, Fondazione IRCCS Ca'Granda, Milan, Italy.
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32
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Subthalamic local field potentials in Parkinson's disease and isolated dystonia: An evaluation of potential biomarkers. Neurobiol Dis 2016; 89:213-22. [PMID: 26884091 DOI: 10.1016/j.nbd.2016.02.015] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Revised: 02/07/2016] [Accepted: 02/10/2016] [Indexed: 12/18/2022] Open
Abstract
Local field potentials (LFP) recorded from the subthalamic nucleus in patients with Parkinson's disease (PD) demonstrate prominent oscillations in the beta (13-30 Hz) frequency range, and reduction of beta band spectral power by levodopa and deep brain stimulation (DBS) is correlated with motor symptom improvement. Several features of beta activity have been theorized to be specific biomarkers of the parkinsonian state, though these have rarely been studied in non-parkinsonian conditions. To compare resting state LFP features in PD and isolated dystonia and evaluate disease-specific biomarkers, we recorded subthalamic LFPs from 28 akinetic-rigid PD and 12 isolated dystonia patients during awake DBS implantation. Spectral power and phase-amplitude coupling characteristics were analyzed. In 26/28 PD and 11/12 isolated dystonia patients, the LFP power spectrum had a peak in the beta frequency range, with similar amplitudes between groups. Resting state power did not differ between groups in the theta (5-8 Hz), alpha (8-12 Hz), beta (13-30 Hz), broadband gamma (50-200 Hz), or high frequency oscillation (HFO, 250-350 Hz) bands. Analysis of phase-amplitude coupling between low frequency phase and HFO amplitude revealed significant interactions in 19/28 PD and 6/12 dystonia recordings without significant differences in maximal coupling or preferred phase. Two features of subthalamic LFPs that have been proposed as specific parkinsonian biomarkers, beta power and coupling of beta phase to HFO amplitude, were also present in isolated dystonia, including focal dystonias. This casts doubt on the utility of these metrics as disease-specific diagnostic biomarkers.
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Beudel M, Brown P. Adaptive deep brain stimulation in Parkinson's disease. Parkinsonism Relat Disord 2015; 22 Suppl 1:S123-6. [PMID: 26411502 PMCID: PMC4671979 DOI: 10.1016/j.parkreldis.2015.09.028] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 09/11/2015] [Indexed: 11/16/2022]
Abstract
Although Deep Brain Stimulation (DBS) is an established treatment for Parkinson's disease (PD), there are still limitations in terms of effectivity, side-effects and battery consumption. One of the reasons for this may be that not only pathological but also physiological neural activity can be suppressed whilst stimulating. For this reason, adaptive DBS (aDBS), where stimulation is applied according to the level of pathological activity, might be advantageous. Initial studies of aDBS demonstrate effectiveness in PD, but there are still many questions to be answered before aDBS can be applied clinically. Here we discuss the feedback signals and stimulation algorithms involved in adaptive stimulation in PD and sketch a potential road-map towards clinical application.
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Affiliation(s)
- M Beudel
- Department of Neurology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands
| | - P Brown
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, OX3 9DU, UK; The Medical Research Council Brain Network Dynamics Unit at the University of Oxford, OX1 3TH, UK.
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34
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Priori A. Technology for deep brain stimulation at a gallop. Mov Disord 2015; 30:1206-12. [PMID: 26011821 PMCID: PMC4736681 DOI: 10.1002/mds.26253] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2014] [Revised: 03/13/2015] [Accepted: 03/30/2015] [Indexed: 11/16/2022] Open
Affiliation(s)
- Alberto Priori
- Clinical Center for Neurostimulation, Neurotechnology and Movement Disorders, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, and University of Milan, Italy
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35
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Beudel M, Little S, Pogosyan A, Ashkan K, Foltynie T, Limousin P, Zrinzo L, Hariz M, Bogdanovic M, Cheeran B, Green AL, Aziz T, Thevathasan W, Brown P. Tremor Reduction by Deep Brain Stimulation Is Associated With Gamma Power Suppression in Parkinson's Disease. Neuromodulation 2015; 18:349-54. [PMID: 25879998 PMCID: PMC4829100 DOI: 10.1111/ner.12297] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Objectives Rest tremor is a cardinal symptom of Parkinson's disease (PD), and is readily suppressed by deep brain stimulation (DBS) of the subthalamic nucleus (STN). The therapeutic effect of the latter on bradykinesia and rigidity has been associated with the suppression of exaggerated beta (13–30 Hz) band synchronization in the vicinity of the stimulating electrode, but there is no correlation between beta suppression and tremor amplitude. In the present study, we investigate whether tremor suppression is related to suppression of activities at other frequencies. Materials and Methods We recorded hand tremor and contralateral local field potential (LFP) activity from DBS electrodes during stimulation of the STN in 15 hemispheres in 11 patients with PD. DBS was applied with increasing voltages starting at 0.5 V until tremor suppression was achieved or until 4.5 V was reached. Results Tremor was reduced to 48.9% ± 10.9% of that without DBS once stimulation reached 2.5–3 V (t14 = −4.667, p < 0.001). There was a parallel suppression of low gamma (31–45 Hz) power to 92.5% ± 3% (t14 = −2.348, p = 0.034). This was not seen over a band containing tremor frequencies and their harmonic (4–12 Hz), or over the beta band. Moreover, low gamma power correlated with tremor severity (mean r = 0.43 ± 0.14, p = 0.008) within subjects. This was not the case for LFP power in the other two bands. Conclusions Our findings support a relationship between low gamma oscillations and PD tremor, and reinforce the principle that the subthalamic LFP is a rich signal that may contain information about the severity of multiple different Parkinsonian features.
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Affiliation(s)
- Martijn Beudel
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK.,Department of Neurology, University Medical Centre Groningen, University of Groningen, Groningen, The Netherlands
| | - Simon Little
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Alek Pogosyan
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Keyoumars Ashkan
- Department of Neurosurgery, Kings College Hospital, Kings College London, London, UK
| | - Thomas Foltynie
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, Queen Square, London, UK
| | - Patricia Limousin
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, Queen Square, London, UK
| | - Ludvic Zrinzo
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, Queen Square, London, UK
| | - Marwan Hariz
- Unit of Functional Neurosurgery, Sobell Department of Motor Neuroscience & Movement Disorders, UCL Institute of Neurology, Queen Square, London, UK
| | - Marko Bogdanovic
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Binith Cheeran
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Alexander L Green
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Tipu Aziz
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
| | - Wesley Thevathasan
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK.,Melbourne Brain Centre, Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Melbourne, Victoria, Australia.,The Bionics Institute, Melbourne, Victoria, Australia
| | - Peter Brown
- Nuffield Department of Clinical Neurosciences, John Radcliffe Hospital, University of Oxford, Oxford, UK
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Hohlefeld FU, Ehlen F, Tiedt HO, Krugel LK, Horn A, Kühn AA, Curio G, Klostermann F, Nikulin VV. Correlation between cortical and subcortical neural dynamics on multiple time scales in Parkinson's disease. Neuroscience 2015; 298:145-60. [PMID: 25881724 DOI: 10.1016/j.neuroscience.2015.04.013] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/01/2015] [Revised: 03/16/2015] [Accepted: 04/07/2015] [Indexed: 10/23/2022]
Abstract
Complex amplitude dynamics of dominant alpha oscillations (8-13 Hz) in the cortex can be captured with long-range temporal correlations (LRTC) in healthy subjects and in various diseases. In patients with Parkinson's disease (PD), intra-nuclear coherence was demonstrated in dominant beta rhythms (10-30 Hz) in the basal ganglia. However, so far the relation between cortical LRTC (across tens of seconds) and subcortical coherence (millisecond scale) is unknown. We addressed these "multiscale interactions" by simultaneous recordings of surface electroencephalography (EEG) and deep local field potentials (LFP) from the bilateral subthalamic nucleus (STN) in eight patients with severe PD eligible for deep brain stimulation, who performed a lexical decision task on medication. In the continuous data set LRTC up to 20s were calculated in the amplitude envelope of 8-13-Hz EEG oscillations (across whole scalp), and subcortical coherence was assessed with measures being insensitive to volume conduction artifacts (imaginary part of coherency; iCOH) in 10-20 and 21-30-Hz oscillations in STN-LFP. We showed a significant positive correlation across patients between cortical LRTC (8-13Hz) and subcortical iCOH selectively in 10-20-Hz oscillations in the left STN. Our results suggest a relation between neural dynamics in the most dominant rhythms in the cortex and basal ganglia in PD, extending across multiple time scales (milliseconds vs. tens of seconds). Furthermore, the investigation of multiscale interactions might contribute to our understanding of cortical-subcortical neural coupling in PD.
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Affiliation(s)
- F U Hohlefeld
- Neurophysics Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany.
| | - F Ehlen
- Motor and Cognition Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - H O Tiedt
- Motor and Cognition Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - L K Krugel
- Motor and Cognition Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - A Horn
- Motor Neuroscience Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Virchow, Berlin, Germany
| | - A A Kühn
- Motor Neuroscience Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Virchow, Berlin, Germany
| | - G Curio
- Neurophysics Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany; Bernstein Center for Computational Neuroscience, Berlin, Germany
| | - F Klostermann
- Motor and Cognition Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany
| | - V V Nikulin
- Neurophysics Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany; Bernstein Center for Computational Neuroscience, Berlin, Germany
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Bour LJ, Lourens MAJ, Verhagen R, de Bie RMA, van den Munckhof P, Schuurman PR, Contarino MF. Directional Recording of Subthalamic Spectral Power Densities in Parkinson's Disease and the Effect of Steering Deep Brain Stimulation. Brain Stimul 2015; 8:730-41. [PMID: 25753176 DOI: 10.1016/j.brs.2015.02.002] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Revised: 02/03/2015] [Accepted: 02/06/2015] [Indexed: 10/24/2022] Open
Abstract
BACKGROUND A new 32-contacts deep brain stimulation (DBS) lead, capable of directionally steering stimulation, was tested intraoperatively. OBJECTIVE The aim of this pilot study was to perform recordings from the multidirectional contacts and to investigate the effect of directional current steering on the local field potentials (LFPs). METHODS In eight patients with Parkinson's disease, after standard microelectrode recording and clinical testing, the new lead was temporarily implanted. The 32-channel LFP recordings were measured simultaneously at different depths and directions before and after directional stimulation. RESULTS The spatial distribution of LFPs power spectral densities across the contact array at baseline marked the borders of the subthalamic nucleus (STN) with a significant increase in beta power and with a mean accuracy of approximately 0.6 mm in four patients.The power in the 18.5-30 Hz frequency band varied across different directions in all patients. In the three cases that showed improvement of rigidity, this was higher when current was steered toward the direction with the highest LFP power in the beta band. Subthalamic LFPs in six patients showed a differential frequency-dependent suppression/enhancement of the oscillatory activity in the 10-45 Hz frequency band after four different 'steering' modes as compared to ring mode, suggesting a higher specificity. CONCLUSIONS Through a new 32-contact DBS lead it is possible to record simultaneous subthalamic LFPs at different depths and directions, providing confirmation of adequate lead placement and multidirectional spatial-temporal information potentially related to pathological subthalamic electrical activity and to the effect of stimulation. Although further research is needed, this may improve the efficiency of steering stimulation.
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Affiliation(s)
- L J Bour
- Department of Neurology and Clinical Neurophysiology, Academic Medical Center, University of Amsterdam, the Netherlands.
| | - M A J Lourens
- Department of Neurology and Clinical Neurophysiology, Academic Medical Center, University of Amsterdam, the Netherlands
| | - R Verhagen
- Department of Neurology and Clinical Neurophysiology, Academic Medical Center, University of Amsterdam, the Netherlands
| | - R M A de Bie
- Department of Neurology and Clinical Neurophysiology, Academic Medical Center, University of Amsterdam, the Netherlands
| | - P van den Munckhof
- Department of Neurosurgery, Academic Medical Center, University of Amsterdam, the Netherlands
| | - P R Schuurman
- Department of Neurosurgery, Academic Medical Center, University of Amsterdam, the Netherlands
| | - M F Contarino
- Department of Neurology and Clinical Neurophysiology, Academic Medical Center, University of Amsterdam, the Netherlands; Department of Neurology, Haga Teaching Hospital, the Hague, the Netherlands.
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Denison T, Litt B. Advancing neuromodulation through control systems: a general framework and case study in posture-responsive stimulation. Neuromodulation 2015; 17 Suppl 1:48-57. [PMID: 24974775 DOI: 10.1111/ner.12170] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2012] [Revised: 02/08/2013] [Accepted: 03/13/2013] [Indexed: 11/26/2022]
Abstract
OBJECTIVES To provide a general control system framework for neuromodulation, its practical challenges, and historical underpinnings in cardiac rhythm devices, and to illustrate the potential of closed-loop techniques in neuromodulation with a case study using an adaptive neural stimulation system that integrates sensing, actuation, and state estimation for the treatment of chronic pain through spinal cord stimulation. MATERIALS AND METHODS The current state of neuromodulation can be viewed in a classical dynamic control framework: the nervous system is the classical "plant," the neural stimulator is the actuator, tools to collect clinical data are the sensors, and the physician's judgment is the state estimator and mechanism for closing the therapy feedback loop. This framework highlights the opportunities available to advance neuromodulation. RESULTS Technology has the capability to address key factors limiting the performance of current systems: observability, the ability of the device to monitor the state of the nervous system from sensor-based measurements in real time; and controllability, the ability of the device to drive the nervous system to a desired physiological state using suitable algorithms and actuation. CONCLUSIONS Technological advances in neuromodulation using such a control framework have the potential to improve neurologic therapies. Future opportunities for extending the role of these systems are briefly discussed.
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Hohlefeld FU, Huchzermeyer C, Huebl J, Schneider GH, Brücke C, Schönecker T, Kühn AA, Curio G, Nikulin VV. Interhemispheric functional interactions between the subthalamic nuclei of patients with Parkinson's disease. Eur J Neurosci 2014; 40:3273-83. [PMID: 25195608 DOI: 10.1111/ejn.12686] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 07/04/2014] [Accepted: 07/09/2014] [Indexed: 02/01/2023]
Abstract
Parkinson's disease (PD) is characterized by widespread neural interactions in cortico-basal-ganglia networks primarily in beta oscillations (approx. 10-30 Hz), as suggested by previous findings of levodopa-modulated interhemispheric coherence between the bilateral subthalamic nuclei (STN) in local field potential recordings (LFPs). However, due to confounding effects of volume conduction the existence of 'genuine' interhemispheric subcortical coherence remains an open question. To address this issue we utilized the imaginary part of coherency (iCOH) which, in contrast to the standard coherence, is not susceptible to volume conduction. LFPs were recorded from eight patients with PD during wakeful rest before and after levodopa administration. We demonstrated genuine coherence between the bilateral STN in both 10-20 and 21-30 Hz oscillations, as revealed by a non-zero iCOH. Crucially, increased iCOH in 10-20 Hz oscillations positively correlated with the worsening of motor symptoms in the OFF medication condition across patients, which was not the case for standard coherence. Furthermore, across patients iCOH was increased after levodopa administration in 21-30 Hz oscillations. These results suggest a functional distinction between low and high beta oscillations in STN-LFP in line with previous studies. Furthermore, the observed functional coupling between the bilateral STN might contribute to the understanding of bilateral effects of unilateral deep brain stimulation. In conclusion, the present results imply a significant contribution of time-delayed neural interactions to interhemispheric coherence, and the clinical relevance of long-distance neural interactions between bilateral STN for motor symptoms in PD.
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Affiliation(s)
- F U Hohlefeld
- Neurophysics Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, Berlin, Germany
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40
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Lungu C, Malone P, Wu T, Ghosh P, McElroy B, Zaghloul K, Patterson T, Hallett M, Levine Z. Temporal macrodynamics and microdynamics of the postoperative impedance at the tissue-electrode interface in deep brain stimulation patients. J Neurol Neurosurg Psychiatry 2014; 85:816-9. [PMID: 24218525 PMCID: PMC7295113 DOI: 10.1136/jnnp-2013-306066] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
OBJECTIVE To study the temporal dynamics of tissue impedance after deep brain stimulation (DBS). BACKGROUND DBS therapy commonly employs a constant voltage approach, and current delivery to the tissue is a function of electrode-tissue impedance. It is presumed that impedance fluctuates early postimplantation, with implications for variations in current delivery and therapeutic efficacy. We hypothesised that the largest variation will be recorded early after surgery, followed by stabilisation. METHODS Review of impedance checks of implanted DBS systems at standard parameters during the first five months postimplantation. All measurement time points were binned into 1-week periods, and we used repeated measures analysis of variance with Tukey pairwise multiple comparisons correction. The analysis was repeated after normalising impedance values for each subject to that patient's baseline value. RESULTS There was an initial (non-significant) drop in impedance at week 1, followed by significant increase at week 3 (p=0.0002). There were no further significant differences in impedance values at subsequent time points. Analysis of normalised data showed a significant difference between the initial measurement in postoperative week 1 (normalised value 1) and week 3 (normalised value 1.73, p<0.0001), with no further difference among the subsequent weekly points during the 5-month follow-up. No significant hourly variations were found at any time points. CONCLUSIONS We found major changes in impedance within the first month postimplantation, with no further variation. This is an important confirmation in patients of this temporal dynamics of the impedance of implanted DBS hardware, with potential therapeutic implications.
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Affiliation(s)
- C Lungu
- NIH Parkinson Clinic, Office of the Clinical Director, NINDS, NIH, Bethesda, Maryland, USA
| | - P Malone
- NIH Parkinson Clinic, Office of the Clinical Director, NINDS, NIH, Bethesda, Maryland, USA
| | - T Wu
- Clinical Neuroscience Program, NINDS, NIH, Bethesda, Maryland, USA
| | - P Ghosh
- NIH Parkinson Clinic, Office of the Clinical Director, NINDS, NIH, Bethesda, Maryland, USA
| | - B McElroy
- NIH Parkinson Clinic, Office of the Clinical Director, NINDS, NIH, Bethesda, Maryland, USA
| | - K Zaghloul
- Surgical Neurology Branch, NINDS, NIH, Bethesda, Maryland, USA
| | - T Patterson
- Neuroscience Department, Marshall University, Huntington, West Virginia, USA
| | - M Hallett
- Medical Neurology Branch, NINDS, NIH, Bethesda, Maryland, USA
| | - Z Levine
- Neurosurgery Department, Holy Cross Hospital, Silver Spring, Maryland, USA
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41
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Kent AR, Grill WM. Analysis of deep brain stimulation electrode characteristics for neural recording. J Neural Eng 2014; 11:046010. [PMID: 24921984 DOI: 10.1088/1741-2560/11/4/046010] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
OBJECTIVE Closed-loop deep brain stimulation (DBS) systems have the potential to optimize treatment of movement disorders by enabling automatic adjustment of stimulation parameters based on a feedback signal. Evoked compound action potentials (ECAPs) and local field potentials (LFPs) recorded from the DBS electrode may serve as suitable closed-loop control signals. The objective of this study was to understand better the factors that influence ECAP and LFP recording, including the physical presence of the electrode, the geometrical dimensions of the electrode, and changes in the composition of the peri-electrode space across recording conditions. APPROACH Coupled volume conductor-neuron models were used to calculate single-unit activity as well as ECAP responses and LFP activity from a population of model thalamic neurons. MAIN RESULTS Comparing ECAPs and LFPs measured with and without the presence of the highly conductive recording contacts, we found that the presence of these contacts had a negligible effect on the magnitude of single-unit recordings, ECAPs (7% RMS difference between waveforms), and LFPs (5% change in signal magnitude). Spatial averaging across the contact surface decreased the ECAP magnitude in a phase-dependent manner (74% RMS difference), resulting from a differential effect of the contact on the contribution from nearby or distant elements, and decreased the LFP magnitude (25% change). Reductions in the electrode diameter or recording contact length increased signal energy and increased spatial sensitivity of single neuron recordings. Moreover, smaller diameter electrodes (500 µm) were more selective for recording from local cells over passing axons, with the opposite true for larger diameters (1500 µm). Changes in electrode dimensions had phase-dependent effects on ECAP characteristics, and generally had small effects on the LFP magnitude. ECAP signal energy and LFP magnitude decreased with tighter contact spacing (100 µm), compared to the original dimensions (1500 µm), with the opposite effect on the ECAP at longer contact-to-contact distances (2000 µm). Finally, acute edema reduced the single neuron and population ECAP signal energy, as well as LFP magnitude, and glial encapsulation had the opposite effect, after accounting for loss of cells in the peri-electrode space. SIGNIFICANCE This study determined recording conditions and electrode designs that influence ECAP and LFP recording fidelity.
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Affiliation(s)
- Alexander R Kent
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
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Satzer D, Lanctin D, Eberly LE, Abosch A. Variation in deep brain stimulation electrode impedance over years following electrode implantation. Stereotact Funct Neurosurg 2014; 92:94-102. [PMID: 24503709 DOI: 10.1159/000358014] [Citation(s) in RCA: 63] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2013] [Accepted: 12/16/2013] [Indexed: 11/19/2022]
Abstract
BACKGROUND Deep brain stimulation (DBS) electrode impedance is a major determinant of current delivery to target tissues, but long-term variation in impedance has received little attention. OBJECTIVES To assess the relationship between electrode impedance and time in a large DBS patient population and characterize the relationship between contact activity and impedance. METHODS We collected retrospective impedance and programming data from 128 electrodes in 84 patients with Parkinson's disease, essential tremor or dystonia. Effects of time, contact activity, stimulation voltage and other parameters on impedance were assessed. We also examined impedance changes following contact activation and deactivation. RESULTS Impedance decreased by 73 Ω/year (p < 0.001), with 72% of contacts following a downward trend. Impedance was on average 163 Ω lower in active contacts (p < 0.001). Contact activation and inactivation were associated with a more (p < 0.001) and less (p = 0.016) rapid decline in impedance, respectively. Higher stimulation voltages were associated with lower impedance values (p < 0.001). Contact number and electrode model were also significant predictors of impedance. CONCLUSIONS Impedance decreases gradually in a stimulation-dependent manner. These trends have implications for long-term programming, the development of a closed-loop DBS device and current understanding of the electrode-tissue interface.
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Affiliation(s)
- David Satzer
- Department of Neurosurgery, University of Minnesota, Minneapolis, Minn., USA
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43
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Marceglia S, Fumagalli M, Priori A. What neurophysiological recordings tell us about cognitive and behavioral functions of the human subthalamic nucleus. Expert Rev Neurother 2014; 11:139-49. [DOI: 10.1586/ern.10.184] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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44
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Pedunculopontine nucleus area oscillations during stance, stepping and freezing in Parkinson's disease. PLoS One 2013; 8:e83919. [PMID: 24386308 PMCID: PMC3875496 DOI: 10.1371/journal.pone.0083919] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2013] [Accepted: 11/10/2013] [Indexed: 12/03/2022] Open
Abstract
The pedunculopontine area (PPNa) including the pedunculopontine and cuneiform nuclei, belongs to the mesencephalic locomotor region. Little is known about the oscillatory mechanisms underlying the function of this region in postural and gait control. We examined the modulations of the oscillatory activity of the PPNa and cortex during stepping, a surrogate of gait, and stance in seven Parkinson’s disease patients who received bilateral PPNa implantation for disabling freezing of gait (FOG). In the days following the surgery, we recorded behavioural data together with the local field potentials of the PPNa during sitting, standing and stepping-in-place, under two dopaminergic medication conditions (OFF and ON levodopa). Our results showed that OFF levodopa, all subjects had FOG during step-in-place trials, while ON levodopa, stepping was effective (mean duration of FOG decreasing from 61.7±36.1% to 7.3±10.1% of trial duration). ON levodopa, there was an increase in PPNa alpha (5–12 Hz) oscillatory activity and a decrease in beta (13–35 Hz) and gamma (65–90 Hz) bands activity. PPNa activity was not modulated during quiet standing and sitting. Our results confirm the role of the PPNa in the regulation of gait and suggest that, in Parkinson disease, gait difficulties could be related to an imbalance between low and higher frequencies.
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45
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Swan BD, Grill WM, Turner DA. Investigation of deep brain stimulation mechanisms during implantable pulse generator replacement surgery. Neuromodulation 2013; 17:419-24; discussion 424. [PMID: 24118257 DOI: 10.1111/ner.12123] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2013] [Revised: 06/11/2013] [Accepted: 08/27/2013] [Indexed: 01/11/2023]
Abstract
BACKGROUND Direct testing of deep brain stimulation (DBS) mechanisms in humans is needed to assess therapy and to understand stimulation effects. OBJECTIVE We developed an innovative paradigm for investigation of DBS on human movement disorders. Temporary connection to the DBS electrode during implantable pulse generator (IPG) replacement permitted analysis of novel patterns of stimulation on motor symptoms, which could enhance efficacy and improve battery life. MATERIALS AND METHODS Patients enrolled in this prospective, Institutional Review Board-approved study underwent IPG replacement using local (monitored) anesthesia. Following device explant, the DBS electrode was connected to an external, isolated electrical stimulator using a sterile adapter cable. Different temporal patterns of stimulation were delivered while quantifying upper-extremity tremor (tri-axial accelerometry) or bradykinesia (finger-tapping). Upon experiment completion, the new IPG was implanted. RESULTS Among 159 IPG replacements from 2005 to 2011, 56 patients agreed to the research study (16 essential tremor [ET], 31 Parkinson's disease [PD], 5 mixed ET/PD tremor, 3 multiple sclerosis, 1 tremor/myoclonus). Surgical procedures were extended by 42 ± 8.2 min in 37 patients completing the study. Motor symptoms varied with stimulation pattern, with some patterns showing improved tremor or bradykinesia control. No postoperative infections or complications were observed in the 159 patients. CONCLUSION IPG replacement occurs when the DBS/brain interface is stable and patients demonstrate symptom reduction with known stimulation parameters. Conducting research at this time point avoids DBS implant issues, including temporary microlesion effects, fluctuating electrode impedances, and technical limitations of contemporary IPGs, providing advantageous conditions to conduct translational DBS research with minimal additional risk to research subjects.
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Affiliation(s)
- Brandon D Swan
- Department of Biomedical Engineering, Duke University, Durham, NC, USA
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Hohlefeld FU, Huchzermeyer C, Huebl J, Schneider GH, Nolte G, Brücke C, Schönecker T, Kühn AA, Curio G, Nikulin VV. Functional and effective connectivity in subthalamic local field potential recordings of patients with Parkinson's disease. Neuroscience 2013; 250:320-32. [PMID: 23876322 DOI: 10.1016/j.neuroscience.2013.07.028] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2013] [Revised: 06/24/2013] [Accepted: 07/11/2013] [Indexed: 01/16/2023]
Abstract
In Parkinson's disease (PD) levodopa-associated changes in the power and long-range temporal correlations of beta oscillations have been demonstrated, yet the presence and modulation of genuine connectivity in local field potentials (LFP) recorded from the subthalamic nucleus (STN) remains an open question. The present study investigated LFP recorded bilaterally from the STN at wakeful rest in ten patients with PD after overnight withdrawal of levodopa (OFF) and after a single dose levodopa administration (ON). We utilized connectivity measures being insensitive to volume conduction (functional connectivity: non-zero imaginary part of coherency; effective connectivity: phase-slope index). We demonstrated the presence of neuronal interactions in the frequency range of 10-30 Hz in STN-LFP without a preferential directionality of interactions between different contacts along the electrode tracks. While the direction of neuronal interactions per se was preserved after levodopa administration, functional connectivity and the ventral-dorsal information flow were modulated by medication. The OFF-ON differences in functional connectivity were correlated with the levodopa-induced improvement in clinical Unified Parkinson's Disease Rating Scale scores. We hypothesize that regional neuronal interactions, as reflected in STN-LFP connectivity, might represent a basis for the intra-nuclear spatial specificity of deep brain stimulation. Moreover, our results suggest the potential use of volume conduction-insensitive measures of connectivity in STN-LFP as a marker of clinical motor symptoms in PD.
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Affiliation(s)
- F U Hohlefeld
- Neurophysics Group, Department of Neurology, Charité - Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany.
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Priori A, Foffani G, Rossi L, Marceglia S. Adaptive deep brain stimulation (aDBS) controlled by local field potential oscillations. Exp Neurol 2013; 245:77-86. [DOI: 10.1016/j.expneurol.2012.09.013] [Citation(s) in RCA: 177] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2012] [Revised: 07/27/2012] [Accepted: 09/20/2012] [Indexed: 10/27/2022]
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Modulation of Beta oscillations in the subthalamic nucleus with prosaccades and antisaccades in Parkinson's disease. J Neurosci 2013; 33:6895-904. [PMID: 23595748 DOI: 10.1523/jneurosci.2564-12.2013] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Increased oscillations in the beta band are thought to be related to motor symptoms of Parkinson's disease (PD). Previous studies have shown that beta-band desynchronization in the subthalamic nucleus (STN) is reduced just before and during limb movements. While the STN is part of the basal ganglia (BG)-thalamocortical circuit controlling limb movements, it is also part of the BG-brainstem projection controlling saccadic eye movements. Late-stage PD patients have deficits in saccades in addition to difficulties with limb movements arising from impaired functions of the BG. We investigated saccade-related changes in beta-band (15-30 Hz) oscillatory activities in the human STN while PD patients performed visually guided prosaccades and antisaccades, the latter requiring suppression of reflexive responses and volitional initiation of saccades. We recorded local field potentials from deep brain stimulation electrodes implanted in the STN in human PD patients 1-5 d after surgery and compared prosaccades and antisaccades with these and with limb movements. Saccade-related beta-band desynchronizations were observed just before and during saccades in all subjects, suggesting that reduction of beta-band oscillatory activity in the STN is related to preparation and execution of saccades. Furthermore, beta-band desynchronizations for antisaccades started earlier, were sustained for longer periods, were of greater magnitude, and were observed more often than prosaccades. Beta-band desynchronization in the STN may reflect the additional processes associated with suppression of reflexive responses and volitional execution of saccades in the opposite direction.
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49
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Rosa M, Fumagalli M, Giannicola G, Marceglia S, Lucchiari C, Servello D, Franzini A, Pacchetti C, Romito L, Albanese A, Porta M, Pravettoni G, Priori A. Pathological gambling in Parkinson's disease: subthalamic oscillations during economics decisions. Mov Disord 2013; 28:1644-52. [PMID: 23554027 DOI: 10.1002/mds.25427] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2012] [Revised: 01/22/2013] [Accepted: 02/01/2013] [Indexed: 01/29/2023] Open
Abstract
Pathological gambling develops in up to 8% of patients with Parkinson's disease. Although the pathophysiology of gambling remains unclear, several findings argue for a dysfunction in the basal ganglia circuits. To clarify the role of the subthalamic nucleus in pathological gambling, we studied its activity during economics decisions. We analyzed local field potentials recorded from deep brain stimulation electrodes in the subthalamic nucleus while parkinsonian patients with (n = 8) and without (n = 9) pathological gambling engaged in an economics decision-making task comprising conflictual trials (involving possible risk-taking) and non conflictual trials. In all parkinsonian patients, subthalamic low frequencies (2-12 Hz) increased during economics decisions. Whereas, in patients without gambling, low-frequency oscillations exhibited a similar pattern during conflictual and non conflictual stimuli, in those with gambling, low-frequency activity increased significantly more during conflictual than during non conflictual stimuli. The specific low-frequency oscillatory pattern recorded in patients with Parkinson's disease who gamble could reflect a subthalamic dysfunction that makes their decisional threshold highly sensitive to risky options. When parkinsonian patients process stimuli related to an economics task, low-frequency subthalamic activity increases. This task-related change suggests that the cognitive-affective system that drives economics decisional processes includes the subthalamic nucleus. The specific subthalamic neuronal activity during conflictual decisions in patients with pathological gambling supports the idea that the subthalamic nucleus is involved in behavioral strategies and in the pathophysiology of gambling.
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Affiliation(s)
- Manuela Rosa
- Centro Clinico per la Neurostimolazione, le Neurotecnologie ed i Disordini del Movimento, Fondazione IRCCS Ca' Granda, Ospedale Maggiore Policlinico, Milan, Italy
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50
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Lempka SF, McIntyre CC. Theoretical analysis of the local field potential in deep brain stimulation applications. PLoS One 2013; 8:e59839. [PMID: 23555799 PMCID: PMC3610913 DOI: 10.1371/journal.pone.0059839] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2012] [Accepted: 02/20/2013] [Indexed: 11/19/2022] Open
Abstract
Deep brain stimulation (DBS) is a common therapy for treating movement disorders, such as Parkinson's disease (PD), and provides a unique opportunity to study the neural activity of various subcortical structures in human patients. Local field potential (LFP) recordings are often performed with either intraoperative microelectrodes or DBS leads and reflect oscillatory activity within nuclei of the basal ganglia. These LFP recordings have numerous clinical implications and might someday be used to optimize DBS outcomes in closed-loop systems. However, the origin of the recorded LFP is poorly understood. Therefore, the goal of this study was to theoretically analyze LFP recordings within the context of clinical DBS applications. This goal was achieved with a detailed recording model of beta oscillations (∼20 Hz) in the subthalamic nucleus. The recording model consisted of finite element models of intraoperative microelectrodes and DBS macroelectrodes implanted in the brain along with multi-compartment cable models of STN projection neurons. Model analysis permitted systematic investigation into a number of variables that can affect the composition of the recorded LFP (e.g. electrode size, electrode impedance, recording configuration, and filtering effects of the brain, electrode-electrolyte interface, and recording electronics). The results of the study suggest that the spatial reach of the LFP can extend several millimeters. Model analysis also showed that variables such as electrode geometry and recording configuration can have a significant effect on LFP amplitude and spatial reach, while the effects of other variables, such as electrode impedance, are often negligible. The results of this study provide insight into the origin of the LFP and identify variables that need to be considered when analyzing LFP recordings in clinical DBS applications.
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Affiliation(s)
- Scott F. Lempka
- Department of Biomedical Engineering, Cleveland Clinic Foundation, Cleveland, Ohio, United States of America
| | - Cameron C. McIntyre
- Department of Biomedical Engineering, Cleveland Clinic Foundation, Cleveland, Ohio, United States of America
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