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Warren AEL, Butson CR, Hook MP, Dalic LJ, Archer JS, Macdonald-Laurs E, Schaper FLWVJ, Hart LA, Singh H, Johnson L, Bullinger KL, Gross RE, Morrell MJ, Rolston JD. Targeting thalamocortical circuits for closed-loop stimulation in Lennox-Gastaut syndrome. Brain Commun 2024; 6:fcae161. [PMID: 38764777 PMCID: PMC11099664 DOI: 10.1093/braincomms/fcae161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2023] [Revised: 03/26/2024] [Accepted: 05/06/2024] [Indexed: 05/21/2024] Open
Abstract
This paper outlines the therapeutic rationale and neurosurgical targeting technique for bilateral, closed-loop, thalamocortical stimulation in Lennox-Gastaut syndrome, a severe form of childhood-onset epilepsy. Thalamic stimulation can be an effective treatment for Lennox-Gastaut syndrome, but complete seizure control is rarely achieved. Outcomes may be improved by stimulating areas beyond the thalamus, including cortex, but the optimal targets are unknown. We aimed to identify a cortical target by synthesizing prior neuroimaging studies, and to use this knowledge to advance a dual thalamic (centromedian) and cortical (frontal) approach for closed-loop stimulation. Multi-modal brain network maps from three group-level studies of Lennox-Gastaut syndrome were averaged to define the area of peak overlap: simultaneous EEG-functional MRI of generalized paroxysmal fast activity, [18F]fluorodeoxyglucose PET of cortical hypometabolism and diffusion MRI structural connectivity associated with clinical efficacy in a previous trial of thalamic deep brain stimulation. The resulting 'hotspot' was used as a seed in a normative functional MRI connectivity analysis to identify connected networks. Intracranial electrophysiology was reviewed in the first two trial patients undergoing bilateral implantations guided by this hotspot. Simultaneous recordings from cortex and thalamus were analysed for presence and synchrony of epileptiform activity. The peak overlap was in bilateral premotor cortex/caudal middle frontal gyrus. Functional connectivity of this hotspot revealed a distributed network of frontoparietal cortex resembling the diffuse abnormalities seen on EEG-functional MRI and PET. Intracranial electrophysiology showed characteristic epileptiform activity of Lennox-Gastaut syndrome in both the cortical hotspot and thalamus; most detected events occurred first in the cortex before appearing in the thalamus. Premotor frontal cortex shows peak involvement in Lennox-Gastaut syndrome and functional connectivity of this region resembles the wider epileptic brain network. Thus, it may be an optimal target for a range of neuromodulation therapies, including thalamocortical stimulation and emerging non-invasive treatments like focused ultrasound or transcranial magnetic stimulation. Compared to thalamus-only approaches, the addition of this cortical target may allow more rapid detections of seizures, more diverse stimulation paradigms and broader modulation of the epileptic network. A prospective, multi-centre trial of closed-loop thalamocortical stimulation for Lennox-Gastaut syndrome is currently underway.
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Affiliation(s)
- Aaron E L Warren
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Christopher R Butson
- Normal Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32608, USA
| | - Matthew P Hook
- Normal Fixel Institute for Neurological Diseases, University of Florida, Gainesville, FL 32608, USA
| | - Linda J Dalic
- University of Melbourne, Parkville, VIC 3052, Australia
- Department of Neurology, Austin Health, Heidelberg, VIC 3084, Australia
| | - John S Archer
- University of Melbourne, Parkville, VIC 3052, Australia
- Department of Neurology, Austin Health, Heidelberg, VIC 3084, Australia
| | - Emma Macdonald-Laurs
- University of Melbourne, Parkville, VIC 3052, Australia
- Department of Neurology, Royal Children’s Hospital, Parkville, VIC 3052, Australia
- Murdoch Children’s Research Institute, Parkville, VIC 3052, Australia
| | - Frederic L W V J Schaper
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Lauren A Hart
- Department of Neurology, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | - Hargunbir Singh
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
| | | | - Katie L Bullinger
- Department of Neurology, Emory University Hospital, Atlanta, GA 30322, USA
| | - Robert E Gross
- Department of Neurosurgery, Emory University Hospital, Atlanta, GA 30322, USA
| | - Martha J Morrell
- NeuroPace, Mountain View, CA 94043, USA
- Department of Neurology and Neurological Science, Stanford University, Palo Alto, CA 94304, USA
| | - John D Rolston
- Department of Neurosurgery, Brigham and Women’s Hospital, Harvard Medical School, Boston, MA 02115, USA
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Macdonald-Laurs E, Warren AEL, Francis P, Mandelstam SA, Lee WS, Coleman M, Stephenson SEM, Barton S, D'Arcy C, Lockhart PJ, Leventer RJ, Harvey AS. The clinical, imaging, pathological and genetic landscape of bottom-of-sulcus dysplasia. Brain 2024; 147:1264-1277. [PMID: 37939785 DOI: 10.1093/brain/awad379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 09/20/2023] [Accepted: 10/22/2023] [Indexed: 11/10/2023] Open
Abstract
Bottom-of-sulcus dysplasia (BOSD) is increasingly recognized as a cause of drug-resistant, surgically-remediable, focal epilepsy, often in seemingly MRI-negative patients. We describe the clinical manifestations, morphological features, localization patterns and genetics of BOSD, with the aims of improving management and understanding pathogenesis. We studied 85 patients with BOSD diagnosed between 2005-2022. Presenting seizure and EEG characteristics, clinical course, genetic findings and treatment response were obtained from medical records. MRI (3 T) and 18F-FDG-PET scans were reviewed systematically for BOSD morphology and metabolism. Histopathological analysis and tissue genetic testing were performed in 64 operated patients. BOSD locations were transposed to common imaging space to study anatomical location, functional network localization and relationship to normal MTOR gene expression. All patients presented with stereotyped focal seizures with rapidly escalating frequency, prompting hospitalization in 48%. Despite 42% patients having seizure remissions, usually with sodium channel blocking medications, most eventually became drug-resistant and underwent surgery (86% seizure-free). Prior developmental delay was uncommon but intellectual, language and executive dysfunction were present in 24%, 48% and 29% when assessed preoperatively, low intellect being associated with greater epilepsy duration. BOSDs were missed on initial MRI in 68%, being ultimately recognized following repeat MRI, 18F-FDG-PET or image postprocessing. MRI features were grey-white junction blurring (100%), cortical thickening (91%), transmantle band (62%), increased cortical T1 signal (46%) and increased subcortical FLAIR signal (26%). BOSD hypometabolism was present on 18F-FDG-PET in 99%. Additional areas of cortical malformation or grey matter heterotopia were present in eight patients. BOSDs predominated in frontal and pericentral cortex and related functional networks, mostly sparing temporal and occipital cortex, and limbic and visual networks. Genetic testing yielded pathogenic mTOR pathway variants in 63% patients, including somatic MTOR variants in 47% operated patients and germline DEPDC5 or NPRL3 variants in 73% patients with familial focal epilepsy. BOSDs tended to occur in regions where the healthy brain normally shows lower MTOR expression, suggesting these regions may be more vulnerable to upregulation of MTOR activity. Consistent with the existing literature, these results highlight (i) clinical features raising suspicion of BOSD; (ii) the role of somatic and germline mTOR pathway variants in patients with sporadic and familial focal epilepsy associated with BOSD; and (iii) the role of 18F-FDG-PET alongside high-field MRI in detecting subtle BOSD. The anatomical and functional distribution of BOSDs likely explain their seizure, EEG and cognitive manifestations and may relate to relative MTOR expression.
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Affiliation(s)
- Emma Macdonald-Laurs
- Department of Neurology, The Royal Children's Hospital, Parkville, Victoria 3052Australia
- Department of Neuroscience, Murdoch Children's Research Institute, Parkville 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
| | - Aaron E L Warren
- Department of Neuroscience, Murdoch Children's Research Institute, Parkville 3052, Australia
- Department of Medicine (Austin Health), The University of Melbourne, Heidelberg 3084, Australia
| | - Peter Francis
- Department of Medical Imaging, The Royal Children's Hospital, Parkville 3052, Australia
| | - Simone A Mandelstam
- Department of Neuroscience, Murdoch Children's Research Institute, Parkville 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
- Department of Medical Imaging, The Royal Children's Hospital, Parkville 3052, Australia
| | - Wei Shern Lee
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
- Department of Genomic Medicine, Bruce Lefroy Centre, Murdoch Children's Research Institute, Parkville 3052, Australia
| | - Matthew Coleman
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
- Department of Genomic Medicine, Bruce Lefroy Centre, Murdoch Children's Research Institute, Parkville 3052, Australia
| | - Sarah E M Stephenson
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
- Department of Genomic Medicine, Bruce Lefroy Centre, Murdoch Children's Research Institute, Parkville 3052, Australia
| | - Sarah Barton
- Department of Neurology, The Royal Children's Hospital, Parkville, Victoria 3052Australia
- Department of Neuroscience, Murdoch Children's Research Institute, Parkville 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
| | - Colleen D'Arcy
- Department of Pathology, The Royal Children's Hospital, Parkville 3052, Australia
| | - Paul J Lockhart
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
- Department of Genomic Medicine, Bruce Lefroy Centre, Murdoch Children's Research Institute, Parkville 3052, Australia
| | - Richard J Leventer
- Department of Neurology, The Royal Children's Hospital, Parkville, Victoria 3052Australia
- Department of Neuroscience, Murdoch Children's Research Institute, Parkville 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
| | - A Simon Harvey
- Department of Neurology, The Royal Children's Hospital, Parkville, Victoria 3052Australia
- Department of Neuroscience, Murdoch Children's Research Institute, Parkville 3052, Australia
- Department of Paediatrics, The University of Melbourne, Parkville 3052, Australia
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Jha R, Blitz SE, Chua MMJ, Warren AEL, Lee JW, Rolston JD. Surgical management of status epilepticus: A systematic review. Epilepsia Open 2024. [PMID: 38456595 DOI: 10.1002/epi4.12924] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2023] [Revised: 11/07/2023] [Accepted: 02/09/2024] [Indexed: 03/09/2024] Open
Abstract
Status Epilepticus (SE), unresponsive to medical management, is associated with high morbidity and mortality. Surgical management is typically considered in these refractory cases. The best surgical approach for affected patients remains unclear; however, given the lack of controlled trials exploring the role of surgery. We performed a systematic review according to PRIMSA guidelines, including case reports and series describing surgical interventions for patients in SE. Cases (157 patients, median age 12.9 years) were followed for a median of 12 months. Patients were in SE for a median of 21 days before undergoing procedures including: focal resection (36.9%), functional hemispherectomy (21%), lobar resection (12.7%), vagus nerve stimulation (VNS) (12.7%), deep brain stimulation (DBS) (6.4%), multiple subpial transection (MST) (3.8%), responsive neurostimulation (RNS) (1.9%), and cortical stimulator placement (1.27%), with 24 patients undergoing multiple procedures. Multiple SE semiologies were identified. 47.8% of patients had focal seizures, and 65% of patients had focal structural abnormalities on MRI. SE persisted for 36.8 ± 47.7 days prior to surgical intervention. SE terminated following surgery in 81.5%, terminated with additional adjuncts in 10.2%, continued in 1.9%, and was not specified in 6.4% of patients. Long-term seizure outcomes were favorable, with the majority improved and 51% seizure-free. Eight patients passed away in follow-up, of which three were in SE. Seizures emerging from one hemisphere were both more likely to immediately terminate (OR 4.7) and lead to long-term seizure-free status (OR 3.9) compared to nonunilateral seizures. No other predictors, including seizure focality, SE duration, or choice of surgical procedure, were predictors of SE termination. Surgical treatment of SE can be effective in terminating SE and leading to sustained seizure freedom, with many different procedures showing efficacy if matched appropriately with SE semiology and etiology. PLAIN LANGUAGE SUMMARY: Patients with persistent seizures (Status Epilepticus) that do not stop following medications can be treated effectively with surgery. Here, we systematically review the entirety of existing literature on surgery for treating status epilepticus to better identify how and when surgery is used and what patients do after surgery.
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Affiliation(s)
- Rohan Jha
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurosurgery, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Sarah E Blitz
- Harvard Medical School, Boston, Massachusetts, USA
- Department of Neurosurgery, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Melissa M J Chua
- Department of Neurosurgery, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Aaron E L Warren
- Department of Neurosurgery, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - Jong Woo Lee
- Department of Neurology, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
| | - John D Rolston
- Department of Neurosurgery, Harvard Medical School, Brigham and Women's Hospital, Boston, Massachusetts, USA
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Warren AEL, Tobochnik S, Chua MMJ, Singh H, Stamm MA, Rolston JD. Neurostimulation for Generalized Epilepsy: Should Therapy be Syndrome-specific? Neurosurg Clin N Am 2024; 35:27-48. [PMID: 38000840 PMCID: PMC10676463 DOI: 10.1016/j.nec.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2023]
Abstract
Current applications of neurostimulation for generalized epilepsy use a one-target-fits-all approach that is agnostic to the specific epilepsy syndrome and seizure type being treated. The authors describe similarities and differences between the 2 "archetypes" of generalized epilepsy-Lennox-Gastaut syndrome and Idiopathic Generalized Epilepsy-and review recent neuroimaging evidence for syndrome-specific brain networks underlying seizures. Implications for stimulation targeting and programming are discussed using 5 clinical questions: What epilepsy syndrome does the patient have? What brain networks are involved? What is the optimal stimulation target? What is the optimal stimulation paradigm? What is the plan for adjusting stimulation over time?
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Affiliation(s)
- Aaron E L Warren
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA.
| | - Steven Tobochnik
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Melissa M J Chua
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Hargunbir Singh
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Michaela A Stamm
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - John D Rolston
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
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Yu T, Cai LY, Torrisi S, Vu AT, Morgan VL, Goodale SE, Ramadass K, Meisler SL, Lv J, Warren AEL, Englot DJ, Cutting L, Chang C, Gore JC, Landman BA, Schilling KG. Distortion correction of functional MRI without reverse phase encoding scans or field maps. Magn Reson Imaging 2023; 103:18-27. [PMID: 37400042 PMCID: PMC10528451 DOI: 10.1016/j.mri.2023.06.016] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 06/27/2023] [Accepted: 06/28/2023] [Indexed: 07/05/2023]
Abstract
Functional magnetic resonance images (fMRI) acquired using echo planar sequences typically suffer from spatial distortions due to susceptibility induced off-resonance fields, which may cause geometric mismatch with structural images and affect subsequent quantification and localization of brain function. State-of-the art distortion correction methods (for example, using FSL's topup or AFNI's 3dQwarp algorithms) require the collection of additional scans - either field maps or images with reverse phase encoding directions (i.e., blip-up/blip-down acquisitions) - to estimate and correct distortions. However, not all imaging protocols acquire these additional data and thus cannot take advantage of these post-acquisition corrections. In this study, we aim to enable state-of-the art processing of historical or limited datasets that do not include specific sequences for distortion correction by using only the acquired functional data and a single commonly acquired structural image. To achieve this, we synthesize an undistorted image with contrast similar to the fMRI data and use the non-distorted synthetic image as an anatomical target for distortion correction. We evaluate the efficacy of this approach, named SynBOLD-DisCo (Synthetic BOLD contrast for Distortion Correction), and show that this distortion correction process yields fMRI data that are geometrically similar to non-distorted structural images, with distortion correction virtually equivalent to acquisitions that do contain both blip-up/blip-down images. Our method is available as a Singularity container, source code, and an executable trained model to facilitate evaluation and integration into existing fMRI preprocessing pipelines.
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Affiliation(s)
- Tian Yu
- Department of Computer Science, Vanderbilt University, Nashville, TN, USA
| | - Leon Y Cai
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Salvatore Torrisi
- San Francisco VA Health Care System, San Francisco, CA, USA; Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - An Thanh Vu
- San Francisco VA Health Care System, San Francisco, CA, USA; Department of Radiology and Biomedical Imaging, University of California, San Francisco, San Francisco, CA, USA
| | - Victoria L Morgan
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Sarah E Goodale
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA
| | - Karthik Ramadass
- Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA
| | - Steven L Meisler
- Program in Speech and Hearing Bioscience and Technology, Harvard University, Cambridge, MA, USA
| | - Jinglei Lv
- School of Biomedical Engineering, Faculty of Engineering, The University of Sydney, Sydney, NSW, Australia; Brain and Mind Centre, The University of Sydney, Sydney, NSW, Australia
| | - Aaron E L Warren
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
| | - Dario J Englot
- Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA; Department of Neurosurgery, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Laurie Cutting
- Department of Computer Science, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt Kennedy Center, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Special Education, Vanderbilt University, Nashville, TN, USA; Department of Psychology, Vanderbilt University, Nashville, TN, USA
| | - Catie Chang
- Department of Computer Science, Vanderbilt University, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA
| | - John C Gore
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA
| | - Bennett A Landman
- Department of Computer Science, Vanderbilt University, Nashville, TN, USA; Department of Biomedical Engineering, Vanderbilt University, Nashville, TN, USA; Department of Radiology and Radiological Sciences, Vanderbilt University Medical Center, Nashville, TN, USA; Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA
| | - Kurt G Schilling
- Vanderbilt University Institute of Imaging Science, Vanderbilt University Medical Center, Nashville, TN, USA; Department of Electrical and Computer Engineering, Vanderbilt University, Nashville, TN, USA.
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Chua MMJ, Vissani M, Liu DD, Schaper FLWVJ, Warren AEL, Caston R, Dworetzky BA, Bubrick EJ, Sarkis RA, Cosgrove GR, Rolston JD. Initial case series of a novel sensing deep brain stimulation device in drug-resistant epilepsy and consistent identification of alpha/beta oscillatory activity: A feasibility study. Epilepsia 2023; 64:2586-2603. [PMID: 37483140 DOI: 10.1111/epi.17722] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Revised: 07/18/2023] [Accepted: 07/18/2023] [Indexed: 07/25/2023]
Abstract
OBJECTIVE Here, we report a retrospective, single-center experience with a novel deep brain stimulation (DBS) device capable of chronic local field potential (LFP) recording in drug-resistant epilepsy (DRE) and explore potential electrophysiological biomarkers that may aid DBS programming and outcome tracking. METHODS Five patients with DRE underwent thalamic DBS, targeting either the bilateral anterior (n = 3) or centromedian (n = 2) nuclei. Postoperative electrode lead localizations were visualized in Lead-DBS software. Local field potentials recorded over 12-18 months were tracked, and changes in power were associated with patient events, medication changes, and stimulation. We utilized a combination of lead localization, in-clinic broadband LFP recordings, real-time LFP response to stimulation, and chronic recordings to guide DBS programming. RESULTS Four patients (80%) experienced a >50% reduction in seizure frequency, whereas one patient had no significant reduction. Peaks in the alpha and/or beta frequency range were observed in the thalamic LFPs of each patient. Stimulation suppressed these LFP peaks in a dose-dependent manner. Chronic timeline data identified changes in LFP amplitude associated with stimulation, seizure occurrences, and medication changes. We also noticed a circadian pattern of LFP amplitudes in all patients. Button-presses during seizure events via a mobile application served as a digital seizure diary and were associated with elevations in LFP power. SIGNIFICANCE We describe an initial cohort of patients with DRE utilizing a novel sensing DBS device to characterize potential LFP biomarkers of epilepsy that may be associated with seizure control after DBS in DRE. We also present a new workflow utilizing the Percept device that may optimize DBS programming using real-time and chronic LFP recording.
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Affiliation(s)
- Melissa M J Chua
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Matteo Vissani
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - David D Liu
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Frederic L W V J Schaper
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Aaron E L Warren
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Rose Caston
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah, USA
- Department of Neurosurgery, University of Utah, Salt Lake City, Utah, USA
| | - Barbara A Dworetzky
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Ellen J Bubrick
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Rani A Sarkis
- Department of Neurology, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - G Rees Cosgrove
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - John D Rolston
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
- Department of Biomedical Engineering, University of Utah, Salt Lake City, Utah, USA
- Department of Neurosurgery, University of Utah, Salt Lake City, Utah, USA
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Chua MMJ, Warren AEL, Cosgrove GR, Rolston JD. Publication Rates and Characteristics of Clinical Trials in Deep Brain and Responsive Neurostimulation. Stereotact Funct Neurosurg 2023; 101:287-300. [PMID: 37552969 DOI: 10.1159/000531161] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2023] [Accepted: 05/15/2023] [Indexed: 08/10/2023]
Abstract
INTRODUCTION Prompt dissemination of clinical trial results is essential for ensuring the safety and efficacy of intracranial neurostimulation treatments, including deep brain stimulation (DBS) and responsive neurostimulation (RNS). However, the frequency and completeness of results publication, and reasons for reporting delays, are unknown. Moreover, the patient populations, targeted anatomical locations, and stimulation parameters should be clearly reported for both reproducibility and to identify lacunae in trial design. Here, we examine DBS and RNS trials from 1997 to 2022, chart their characteristics, and examine rates and predictors of results reporting. METHODS Trials were identified using ClinicalTrials.gov. Associated publications were identified using ClinicalTrials.gov and PubMed.gov. Pearson's χ2 tests were used to assess differences in trial characteristics between published and unpublished trials. RESULTS Across 449 trials, representing a cumulative cohort of 42,769 patient interventions, there were 37 therapeutic indications and 44 stimulation targets. The most common indication and target were Parkinson's disease (40.55%) and the subthalamic nucleus (35.88%), respectively. Only 0.89% of trials were in pediatric patients (11.58% were mixed pediatric and adult). Explored targets represented 75% of potential basal ganglia targets but only 29% of potential thalamic targets. Allowing a 1-year grace period after trial completion, 34/169 (20.12%) had results reported on ClinicalTrials.gov, and 107/169 (63.31%) were published. ∼80% of published trials included details about stimulation parameters used. Published and unpublished trials did not significantly differ by trial characteristics. CONCLUSION We highlight key knowledge and performance gaps in DBS and RNS trial research. Over one-third of trials remain unpublished >1 year after completion; pediatric trials are scarce; most of the thalamus remains unexplored; about one-in-five trials fail to report stimulation parameters; and movement disorders comprise the most studied indications.
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Affiliation(s)
- Melissa M J Chua
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - Aaron E L Warren
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - G Rees Cosgrove
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
| | - John D Rolston
- Department of Neurosurgery, Brigham and Women's Hospital, Harvard Medical School, Boston, Massachusetts, USA
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Macdonald‐Laurs E, Warren AEL, Lee WS, Yang JY, MacGregor D, Lockhart PJ, Leventer RJ, Neal A, Harvey AS. Intrinsic and secondary epileptogenicity in focal cortical dysplasia type II. Epilepsia 2023; 64:348-363. [PMID: 36527426 PMCID: PMC10952144 DOI: 10.1111/epi.17495] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2022] [Revised: 12/15/2022] [Accepted: 12/15/2022] [Indexed: 12/23/2022]
Abstract
OBJECTIVE Favorable seizure outcome is reported following resection of bottom-of-sulcus dysplasia (BOSD). We assessed the distribution of epileptogenicity and dysplasia in and around BOSD to better understand this clinical outcome and the optimal surgical approach. METHODS We studied 27 children and adolescents with magnetic resonance imaging (MRI)-positive BOSD who underwent epilepsy surgery; 85% became seizure-free postresection (median = 5.0 years follow-up). All patients had resection of the dysplastic sulcus, and 11 had additional resection of the gyral crown (GC) or adjacent gyri (AG). Markers of epileptogenicity were relative cortical hypometabolism on preoperative 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET), and spiking, ripples, fast ripples, spike-high-frequency oscillation cross-rate, and phase amplitude coupling (PAC) on preresection and postresection electrocorticography (ECoG), all analyzed at the bottom-of-sulcus (BOS), top-of-sulcus (TOS), GC, and AG. Markers of dysplasia were increased cortical thickness on preoperative MRI, and dysmorphic neuron density and variant allele frequency of somatic MTOR mutations in resected tissue, analyzed at similar locations. RESULTS Relative cortical metabolism was significantly reduced and ECoG markers were significantly increased at the BOS compared to other regions. Apart from spiking and PAC, which were greater at the TOS compared to the GC, there were no significant differences in PET and other ECoG markers between the TOS, GC, and AG, suggesting a cutoff of epileptogenicity at the TOS rather than a tapering gradient on the cortical surface. MRI and tissue markers of dysplasia were all maximal in the BOS, reduced in the TOS, and mostly absent in the GC. Spiking and PAC reduced significantly over the GC after resection of the dysplastic sulcus. SIGNIFICANCE These findings support the concept that dysplasia and intrinsic epileptogenicity are mostly limited to the dysplastic sulcus in BOSD and support resection or ablation confined to the MRI-visible lesion as a first-line surgical approach. 18 F-FDG PET and ECoG abnormalities in surrounding cortex seem to be secondary phenomena.
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Affiliation(s)
- Emma Macdonald‐Laurs
- Department of NeurologyRoyal Children's HospitalParkvilleVictoriaAustralia
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
- Department of PaediatricsUniversity of MelbourneParkvilleVictoriaAustralia
| | - Aaron E. L. Warren
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
- Department of MedicineUniversity of MelbourneParkvilleVictoriaAustralia
| | - Wei Shern Lee
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
- Department of PaediatricsUniversity of MelbourneParkvilleVictoriaAustralia
| | - Joseph Yuan‐Mou Yang
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
- Department of PaediatricsUniversity of MelbourneParkvilleVictoriaAustralia
- Department of NeurosurgeryRoyal Children's HospitalParkvilleVictoriaAustralia
| | - Duncan MacGregor
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
- Department of PathologyRoyal Children's HospitalParkvilleVictoriaAustralia
| | - Paul J. Lockhart
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
- Department of PaediatricsUniversity of MelbourneParkvilleVictoriaAustralia
| | - Richard J. Leventer
- Department of NeurologyRoyal Children's HospitalParkvilleVictoriaAustralia
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
- Department of PaediatricsUniversity of MelbourneParkvilleVictoriaAustralia
| | - Andrew Neal
- Department of Neuroscience, Faculty of Medicine, Nursing, and Health Sciences, Central Clinical SchoolMonash UniversityMelbourneVictoriaAustralia
| | - A. Simon Harvey
- Department of NeurologyRoyal Children's HospitalParkvilleVictoriaAustralia
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
- Department of PaediatricsUniversity of MelbourneParkvilleVictoriaAustralia
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Dalic LJ, Warren AEL, Spiegel C, Thevathasan W, Roten A, Bulluss KJ, Archer JS. Paroxysmal fast activity is a biomarker of treatment response in deep brain stimulation for Lennox-Gastaut syndrome. Epilepsia 2022; 63:3134-3147. [PMID: 36114808 PMCID: PMC10946931 DOI: 10.1111/epi.17414] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2022] [Revised: 09/15/2022] [Accepted: 09/16/2022] [Indexed: 01/11/2023]
Abstract
OBJECTIVE Epilepsy treatment trials typically rely on seizure diaries to determine seizure frequency, but these are time-consuming and difficult to maintain accurately. Fast, reliable, and objective biomarkers of treatment response are needed, particularly in Lennox-Gastaut syndrome (LGS), where high seizure frequency and comorbid cognitive and behavioral issues are additional obstacles to accurate diary-keeping. Here, we measured generalized paroxysmal fast activity (GPFA), a key interictal electrographic feature of LGS, and correlated GPFA burden with seizure diaries during a thalamic deep brain stimulation (DBS) treatment trial (Electrical Stimulation of the Thalamus in Epilepsy of Lennox-Gastaut Phenotype [ESTEL]). METHODS GPFA and electrographic seizure counts from intermittent, 24-h electroencephalograms (EEGs) were compared to 3-month diary-recorded seizure counts in 17 young adults with LGS (mean age ± SD = 24.9 ± 6.6) in the ESTEL study, a randomized clinical trial of DBS lasting 12 months (comprising a 3-month baseline and 9 months of postimplantation follow-up). RESULTS Baseline median seizures measured by diaries numbered 2.6 (interquartile range [IQR] = 1.4-5) per day, compared to 284 (IQR = 120.5-360) electrographic seizures per day, confirming that diaries capture only a small fraction of seizure burden. Across all patient EEGs, the average number of GPFA discharges per hour of sleep was 138 (IQR =72-258). GPFA duration and frequency, quantified over 2-h windows of sleep EEG, were significantly associated with diary-recorded seizure counts over 3-month intervals (p < .001, η2 p = .30-.48). For every GPFA discharge, there were 20-25 diary seizures witnessed over 3 months. There was high between-patient variability in the ratio between diary seizure burden and GPFA burden; however, within individual patients, the ratio was similar over time, such that the percentage change from pre-DBS baseline in seizure diaries strongly correlated with the percentage change in GPFA. SIGNIFICANCE When seeking to optimize treatment in patients with LGS, monitoring changes in GPFA may allow rapid titration of treatment parameters, rather than waiting for feedback from seizure diaries.
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Affiliation(s)
- Linda J. Dalic
- Department of Medicine, Austin HealthUniversity of MelbourneHeidelbergVictoriaAustralia
- Department of Neurology, Austin HealthHeidelbergVictoriaAustralia
| | - Aaron E. L. Warren
- Department of Medicine, Austin HealthUniversity of MelbourneHeidelbergVictoriaAustralia
- The Florey Institute of Neuroscience and Mental HealthHeidelbergVictoriaAustralia
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
| | - Chloe Spiegel
- Department of Neurology, Austin HealthHeidelbergVictoriaAustralia
| | - Wesley Thevathasan
- Department of Medicine, Austin HealthUniversity of MelbourneHeidelbergVictoriaAustralia
- Bionics InstituteEast MelbourneVictoriaAustralia
- Department of MedicineUniversity of Melbourne, and Department of Neurology, Royal Melbourne HospitalParkvilleVictoriaAustralia
| | - Annie Roten
- Department of Neurology, Austin HealthHeidelbergVictoriaAustralia
| | - Kristian J. Bulluss
- Bionics InstituteEast MelbourneVictoriaAustralia
- Department of Neurosurgery, Austin HealthHeidelbergVictoriaAustralia
- Department of SurgeryUniversity of MelbourneParkvilleVictoriaAustralia
| | - John S. Archer
- Department of Medicine, Austin HealthUniversity of MelbourneHeidelbergVictoriaAustralia
- Department of Neurology, Austin HealthHeidelbergVictoriaAustralia
- The Florey Institute of Neuroscience and Mental HealthHeidelbergVictoriaAustralia
- Murdoch Children's Research InstituteParkvilleVictoriaAustralia
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10
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Dalic LJ, Warren AEL, Bulluss KJ, Thevathasan W, Roten A, Churilov L, Archer JS. DBS of Thalamic Centromedian Nucleus for Lennox-Gastaut Syndrome (ESTEL Trial). Ann Neurol 2021; 91:253-267. [PMID: 34877694 DOI: 10.1002/ana.26280] [Citation(s) in RCA: 49] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2021] [Revised: 11/22/2021] [Accepted: 12/05/2021] [Indexed: 02/06/2023]
Abstract
OBJECTIVE Prior uncontrolled studies have reported seizure reductions following deep brain stimulation (DBS) in patients with Lennox-Gastaut syndrome (LGS), but evidence from randomized controlled studies is lacking. We aimed to formally assess the efficacy and safety of DBS to the centromedian thalamic nucleus (CM) for the treatment of LGS. METHODS We conducted a prospective, double-blind, randomized study of continuous, cycling stimulation of CM-DBS, in patients with LGS. Following pre- and post-implantation periods, half received 3 months of stimulation (blinded phase), then all received 3 months of stimulation (unblinded phase). The primary outcome was the proportion of participants with ≥50% reduction in diary-recorded seizures in stimulated versus control participants, measured at the end of the blinded phase. A secondary outcome was the proportion of participants with a ≥50% reduction in electrographic seizures on 24-hour ambulatory electroencephalography (EEG) at the end of the blinded phase. RESULTS Between November 2017 and December 2019, 20 young adults with LGS (17-37 years;13 women) underwent bilateral CM-DBS at a single center in Australia, with 19 randomized (treatment, n = 10 and control, n = 9). Fifty percent of the stimulation group achieved ≥50% seizure reduction, compared with 22% of controls (odds ratio [OR] = 3.1, 95% confidence interval [CI] = 0.44-21.45, p = 0.25). For electrographic seizures, 59% of the stimulation group had ≥50% reduction at the end of the blinded phase, compared with none of the controls (OR= 23.25, 95% CI = 1.0-538.4, p = 0.05). Across all patients, median seizure reduction (baseline vs study exit) was 46.7% (interquartile range [IQR] = 28-67%) for diary-recorded seizures and 53.8% (IQR = 27-73%) for electrographic seizures. INTERPRETATION CM-DBS in patients with LGS reduced electrographic rather than diary-recorded seizures, after 3 months of stimulation. Fifty percent of all participants had diary-recorded seizures reduced by half at the study exit, providing supporting evidence of the treatment effect. ANN NEUROL 2021.
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Affiliation(s)
- Linda J Dalic
- Department of Medicine (Austin Health), University of Melbourne, Heidelberg, VIC, Australia.,Department of Neurology, Austin Health, Heidelberg, VIC, Australia
| | - Aaron E L Warren
- Department of Medicine (Austin Health), University of Melbourne, Heidelberg, VIC, Australia.,The Florey Institute of Neuroscience and Mental Health, Heidelberg, VIC, Australia.,Murdoch Children's Research Institute, Parkville, VIC, Australia
| | - Kristian J Bulluss
- Bionics Institute, East Melbourne, VIC, Australia.,Department of Neurosurgery, Austin Health, Heidelberg, VIC, Australia.,Department of Surgery, University of Melbourne, Parkville, VIC, Australia
| | - Wesley Thevathasan
- Department of Medicine (Austin Health), University of Melbourne, Heidelberg, VIC, Australia.,Bionics Institute, East Melbourne, VIC, Australia.,Department of Medicine, University of Melbourne, and Department of Neurology, The Royal Melbourne Hospital, Parkville, VIC, Australia
| | - Annie Roten
- Department of Neurology, Austin Health, Heidelberg, VIC, Australia
| | - Leonid Churilov
- Department of Medicine (Austin Health), University of Melbourne, Heidelberg, VIC, Australia
| | - John S Archer
- Department of Medicine (Austin Health), University of Melbourne, Heidelberg, VIC, Australia.,Department of Neurology, Austin Health, Heidelberg, VIC, Australia.,The Florey Institute of Neuroscience and Mental Health, Heidelberg, VIC, Australia.,Murdoch Children's Research Institute, Parkville, VIC, Australia
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11
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Macdonald-Laurs E, Maixner WJ, Bailey CA, Barton SM, Mandelstam SA, Yuan-Mou Yang J, Warren AEL, Kean MJ, Francis P, MacGregor D, D'Arcy C, Wrennall JA, Davidson A, Pope K, Leventer RJ, Freeman JL, Wray A, Jackson GD, Harvey AS. One-Stage, Limited-Resection Epilepsy Surgery for Bottom-of-Sulcus Dysplasia. Neurology 2021; 97:e178-e190. [PMID: 33947776 DOI: 10.1212/wnl.0000000000012147] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2020] [Accepted: 03/31/2021] [Indexed: 11/15/2022] Open
Abstract
OBJECTIVE To determine whether 1-stage, limited corticectomy controls seizures in patients with MRI-positive, bottom-of-sulcus dysplasia (BOSD). METHODS We reviewed clinical, neuroimaging, electrocorticography (ECoG), operative, and histopathology findings in consecutively operated patients with drug-resistant focal epilepsy and MRI-positive BOSD, all of whom underwent corticectomy guided by MRI and ECoG. RESULTS Thirty-eight patients with a median age at surgery of 10.2 (interquartile range [IQR] 6.0-14.1) years were included. BOSDs involved eloquent cortex in 15 patients. Eighty-seven percent of patients had rhythmic spiking on preresection ECoG. Rhythmic spiking was present in 22 of 24 patients studied with combined depth and surface electrodes, being limited to the dysplastic sulcus in 7 and involving the dysplastic sulcus and gyral crown in 15. Sixty-eight percent of resections were limited to the dysplastic sulcus, leaving the gyral crown. Histopathology was focal cortical dysplasia (FCD) type IIb in 29 patients and FCDIIa in 9. Dysmorphic neurons were present in the bottom of the sulcus but not the top or the gyral crown in 17 of 22 patients. Six (16%) patients required reoperation for postoperative seizures and residual dysplasia; reoperation was not correlated with ECoG, neuroimaging, or histologic abnormalities in the gyral crown. At a median 6.3 (IQR 4.8-9.9) years of follow-up, 33 (87%) patients are seizure-free, 31 off antiseizure medication. CONCLUSION BOSD can be safely and effectively resected with MRI and ECoG guidance, corticectomy potentially being limited to the dysplastic sulcus, without need for intracranial EEG monitoring and functional mapping. CLASSIFICATION OF EVIDENCE This study provides Class IV evidence that 1-stage, limited corticectomy for BOSD is safe and effective for control of seizures.
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Affiliation(s)
- Emma Macdonald-Laurs
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Wirginia J Maixner
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Catherine A Bailey
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Sarah M Barton
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Simone A Mandelstam
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Joseph Yuan-Mou Yang
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Aaron E L Warren
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Michael J Kean
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Peter Francis
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Duncan MacGregor
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Colleen D'Arcy
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Jacquie A Wrennall
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Andrew Davidson
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Kate Pope
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Richard J Leventer
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Jeremy L Freeman
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Alison Wray
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - Graeme D Jackson
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia
| | - A Simon Harvey
- From the Departments of Neurology (E.M.-L., C.A.B., S.M.B., R.J.L., J.L.F., A.S.H.), Neurosurgery (W.J.M., J.Y.-M.Y., A.E.L.W., A.W.), Medical Imaging (S.A.M., M.J.K., P.F.), Anatomical Pathology (D.M., C.D.), Psychology (J.A.W.), and Anaesthesia (A.D.), The Royal Children's Hospital; Murdoch Children's Research Institute (E.M.-L., W.J.M., S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., C.D., A.D., K.P., R.J.L., A.W., A.S.H.); University of Melbourne (E.M.-L., W.J.M, S.M.B., S.A.M., J.Y.-M.Y., A.E.L.W., M.J.K., C.D., A.D., R.J.L., A.S.H.); and Florey Institute of Neuroscience and Mental Health (A.E.L.W., G.D.J., A.S.H.), Parkville, Victoria, Australia.
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Dalic LJ, Warren AEL, Young JC, Thevathasan W, Roten A, Bulluss KJ, Archer JS. Cortex leads the thalamic centromedian nucleus in generalized epileptic discharges in Lennox‐Gastaut syndrome. Epilepsia 2020; 61:2214-2223. [DOI: 10.1111/epi.16657] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2020] [Revised: 07/23/2020] [Accepted: 07/24/2020] [Indexed: 01/01/2023]
Affiliation(s)
- Linda J. Dalic
- Department of Medicine (Austin Health) University of Melbourne Heidelberg Victoria Australia
- Department of Neurology Austin Health Heidelberg Victoria Australia
| | - Aaron E. L. Warren
- Department of Medicine (Austin Health) University of Melbourne Heidelberg Victoria Australia
- Florey Institute of Neuroscience and Mental Health Heidelberg Victoria Australia
- Murdoch Children’s Research Institute Parkville Victoria Australia
| | - James C. Young
- Florey Institute of Neuroscience and Mental Health Heidelberg Victoria Australia
| | - Wesley Thevathasan
- Department of Medicine (Austin Health) University of Melbourne Heidelberg Victoria Australia
- Bionics Institute East Melbourne Victoria Australia
- Department of Medicine Royal Melbourne Hospital and Department of Neurology University of Melbourne Parkville Victoria Australia
| | - Annie Roten
- Department of Neurology Austin Health Heidelberg Victoria Australia
| | - Kristian J. Bulluss
- Bionics Institute East Melbourne Victoria Australia
- Department of Neurosurgery Austin Health Heidelberg Victoria Australia
- Department of Surgery University of Melbourne Parkville Victoria Australia
| | - John S. Archer
- Department of Medicine (Austin Health) University of Melbourne Heidelberg Victoria Australia
- Department of Neurology Austin Health Heidelberg Victoria Australia
- Florey Institute of Neuroscience and Mental Health Heidelberg Victoria Australia
- Murdoch Children’s Research Institute Parkville Victoria Australia
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13
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Warren AEL, Dalic LJ, Thevathasan W, Roten A, Bulluss KJ, Archer J. Targeting the centromedian thalamic nucleus for deep brain stimulation. J Neurol Neurosurg Psychiatry 2020; 91:339-349. [PMID: 31980515 DOI: 10.1136/jnnp-2019-322030] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Revised: 12/13/2019] [Accepted: 12/23/2019] [Indexed: 12/25/2022]
Abstract
OBJECTIVES Deep brain stimulation (DBS) of the centromedian thalamic nucleus (CM) is an emerging treatment for multiple brain diseases, including the drug-resistant epilepsy Lennox-Gastaut syndrome (LGS). We aimed to improve neurosurgical targeting of the CM by: (1) developing a structural MRI approach for CM visualisation, (2) identifying the CM's neurophysiological characteristics using microelectrode recordings (MERs) and (3) mapping connectivity from CM-DBS sites using functional MRI (fMRI). METHODS 19 patients with LGS (mean age=28 years) underwent presurgical 3T MRI using magnetisation-prepared 2 rapid acquisition gradient-echoes (MP2RAGE) and fMRI sequences; 16 patients proceeded to bilateral CM-DBS implantation and intraoperative thalamic MERs. CM visualisation was achieved by highlighting intrathalamic borders on MP2RAGE using Sobel edge detection. Mixed-effects analysis compared two MER features (spike firing rate and background noise) between ventrolateral, CM and parafasicular nuclei. Resting-state fMRI connectivity was assessed using implanted CM-DBS electrode positions as regions of interest. RESULTS The CM appeared as a hyperintense region bordering the comparatively hypointense pulvinar, mediodorsal and parafasicular nuclei. At the group level, reduced spike firing and background noise distinguished CM from the ventrolateral nucleus; however, these trends were not found in 20%-25% of individual MER trajectories. Areas of fMRI connectivity included basal ganglia, brainstem, cerebellum, sensorimotor/premotor and limbic cortex. CONCLUSIONS In the largest clinical trial of DBS undertaken in patients with LGS to date, we show that accurate targeting of the CM is achievable using 3T MP2RAGE MRI. Intraoperative MERs may provide additional localising features in some cases; however, their utility is limited by interpatient variability. Therapeutic effects of CM-DBS may be mediated via connectivity with brain networks that support diverse arousal, cognitive and sensorimotor processes.
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Affiliation(s)
- Aaron E L Warren
- Department of Medicine (Austin Health), The University of Melbourne, Melbourne, Victoria, Australia .,The Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia.,Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - Linda J Dalic
- Department of Medicine (Austin Health), The University of Melbourne, Melbourne, Victoria, Australia.,The Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia.,Department of Neurology, Austin Health, Heidelberg, Victoria, Australia
| | - Wesley Thevathasan
- Department of Neurology, Austin Health, Heidelberg, Victoria, Australia.,Bionics Institute, East Melbourne, Victoria, Australia.,Department of Medicine (Royal Melbourne Hospital), The University of Melbourne, Parkville, Victoria, Australia.,Department of Neurology, Royal Melbourne Hospital, Parkville, Victoria, Australia
| | - Annie Roten
- Department of Medicine (Austin Health), The University of Melbourne, Melbourne, Victoria, Australia.,Department of Neurology, Austin Health, Heidelberg, Victoria, Australia
| | - Kristian J Bulluss
- Bionics Institute, East Melbourne, Victoria, Australia.,Department of Neurosurgery, Austin Health, Heidelberg, Victoria, Australia.,Department of Surgery, The University of Melbourne, Parkville, Victoria, Australia
| | - John Archer
- Department of Medicine (Austin Health), The University of Melbourne, Melbourne, Victoria, Australia.,The Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia.,Murdoch Children's Research Institute, Parkville, Victoria, Australia.,Department of Neurology, Austin Health, Heidelberg, Victoria, Australia
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Warren AEL, Abbott DF, Jackson GD, Archer JS. Thalamocortical functional connectivity in Lennox-Gastaut syndrome is abnormally enhanced in executive-control and default-mode networks. Epilepsia 2017; 58:2085-2097. [PMID: 29098688 DOI: 10.1111/epi.13932] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/01/2017] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To identify abnormal thalamocortical circuits in the severe epilepsy of Lennox-Gastaut syndrome (LGS) that may explain the shared electroclinical phenotype and provide potential treatment targets. METHODS Twenty patients with a diagnosis of LGS (mean age = 28.5 years) and 26 healthy controls (mean age = 27.6 years) were compared using task-free functional magnetic resonance imaging (MRI). The thalamus was parcellated according to functional connectivity with 10 cortical networks derived using group-level independent component analysis. For each cortical network, we assessed between-group differences in thalamic functional connectivity strength using nonparametric permutation-based tests. Anatomical locations were identified by quantifying spatial overlap with a histologically informed thalamic MRI atlas. RESULTS In both groups, posterior thalamic regions showed functional connectivity with visual, auditory, and sensorimotor networks, whereas anterior, medial, and dorsal thalamic regions were connected with networks of distributed association cortex (including the default-mode, anterior-salience, and executive-control networks). Four cortical networks (left and right executive-control network; ventral and dorsal default-mode network) showed significantly enhanced thalamic functional connectivity strength in patients relative to controls. Abnormal connectivity was maximal in mediodorsal and ventrolateral thalamic nuclei. SIGNIFICANCE Specific thalamocortical circuits are affected in LGS. Functional connectivity is abnormally enhanced between the mediodorsal and ventrolateral thalamus and the default-mode and executive-control networks, thalamocortical circuits that normally support diverse cognitive processes. In contrast, thalamic regions connecting with primary and sensory cortical networks appear to be less affected. Our previous neuroimaging studies show that epileptic activity in LGS is expressed via the default-mode and executive-control networks. Results of the present study suggest that the mediodorsal and ventrolateral thalamus may be candidate targets for modulating abnormal network behavior underlying LGS, potentially via emerging thalamic neurostimulation therapies.
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Affiliation(s)
- Aaron E L Warren
- Department of Medicine, University of Melbourne, Heidelberg, Victoria, Australia.,Murdoch Children's Research Institute, Parkville, Victoria, Australia
| | - David F Abbott
- Department of Medicine, University of Melbourne, Heidelberg, Victoria, Australia.,Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia
| | - Graeme D Jackson
- Department of Medicine, University of Melbourne, Heidelberg, Victoria, Australia.,Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia.,Department of Neurology, Austin Health, Heidelberg, Victoria, Australia
| | - John S Archer
- Department of Medicine, University of Melbourne, Heidelberg, Victoria, Australia.,Murdoch Children's Research Institute, Parkville, Victoria, Australia.,Florey Institute of Neuroscience and Mental Health, Heidelberg, Victoria, Australia.,Department of Neurology, Austin Health, Heidelberg, Victoria, Australia
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15
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Warren AEL, Harvey AS, Abbott DF, Vogrin SJ, Bailey C, Davidson A, Jackson GD, Archer JS. Cognitive network reorganization following surgical control of seizures in Lennox-Gastaut syndrome. Epilepsia 2017; 58:e75-e81. [PMID: 28295228 DOI: 10.1111/epi.13720] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 02/12/2017] [Indexed: 01/03/2023]
Abstract
We previously observed that adults with Lennox-Gastaut syndrome (LGS) show abnormal functional connectivity among cognitive networks, suggesting that this may contribute to impaired cognition. Herein we report network reorganization following seizure remission in a child with LGS who underwent functional magnetic resonance imaging (fMRI) before and after resection of a cortical dysplasia. Concurrent electroencephalography (EEG) was acquired during presurgical fMRI. Presurgical and postsurgical functional connectivity were compared using (1) graph theoretical analyses of small-world network organization and node-wise strength; and (2) seed-based analyses of connectivity within and between five functional networks. To explore the specificity of these postsurgical network changes, connectivity was further compared to nine children with LGS who did not undergo surgery. The presurgical EEG-fMRI revealed diffuse activation of association cortex during interictal discharges. Following surgery and seizure control, functional connectivity showed increased small-world organization, stronger connectivity in subcortical structures, and greater within-network integration/between-network segregation. These changes suggest network improvement, and diverged sharply from the comparison group of nonoperated children. Following surgery, this child with LGS achieved seizure control and showed extensive reorganization of networks that underpin cognition. This case illustrates that the epileptic process of LGS can directly contribute to abnormal network organization, and that this network disruption may be reversible.
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Affiliation(s)
- Aaron E L Warren
- Department of Medicine, The University of Melbourne, Heidelberg, Victoria, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
| | - A Simon Harvey
- Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Heidelberg, Victoria, Australia.,Department of Neurology, The Royal Children's Hospital, Parkville, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Heidelberg, Victoria, Australia
| | - David F Abbott
- Department of Medicine, The University of Melbourne, Heidelberg, Victoria, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Heidelberg, Victoria, Australia
| | - Simon J Vogrin
- Murdoch Childrens Research Institute, Melbourne, Victoria, Australia
| | - Catherine Bailey
- Department of Neurology, The Royal Children's Hospital, Parkville, Victoria, Australia
| | - Andrew Davidson
- Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.,Department of Paediatrics, The University of Melbourne, Heidelberg, Victoria, Australia.,Department of Anaesthesia and Pain Management, The Royal Children's Hospital, Parkville, Victoria, Australia
| | - Graeme D Jackson
- Department of Medicine, The University of Melbourne, Heidelberg, Victoria, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Heidelberg, Victoria, Australia.,Department of Neurology, Austin Health, Melbourne, Victoria, Australia
| | - John S Archer
- Department of Medicine, The University of Melbourne, Heidelberg, Victoria, Australia.,Murdoch Childrens Research Institute, Melbourne, Victoria, Australia.,The Florey Institute of Neuroscience and Mental Health, The University of Melbourne, Heidelberg, Victoria, Australia.,Department of Neurology, Austin Health, Melbourne, Victoria, Australia
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Warren AEL, Abbott DF, Vaughan DN, Jackson GD, Archer JS. Abnormal cognitive network interactions in Lennox-Gastaut syndrome: A potential mechanism of epileptic encephalopathy. Epilepsia 2016; 57:812-22. [DOI: 10.1111/epi.13342] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/28/2016] [Indexed: 12/12/2022]
Affiliation(s)
- Aaron E. L. Warren
- Department of Medicine; The University of Melbourne; Heidelberg Victoria Australia
| | - David F. Abbott
- Department of Medicine; The University of Melbourne; Heidelberg Victoria Australia
- The Florey Institute of Neuroscience and Mental Health; Heidelberg Victoria Australia
| | - David N. Vaughan
- The Florey Institute of Neuroscience and Mental Health; Heidelberg Victoria Australia
- Department of Neurology; Austin Health; Heidelberg Victoria Australia
| | - Graeme D. Jackson
- Department of Medicine; The University of Melbourne; Heidelberg Victoria Australia
- The Florey Institute of Neuroscience and Mental Health; Heidelberg Victoria Australia
- Department of Neurology; Austin Health; Heidelberg Victoria Australia
| | - John S. Archer
- Department of Medicine; The University of Melbourne; Heidelberg Victoria Australia
- The Florey Institute of Neuroscience and Mental Health; Heidelberg Victoria Australia
- Department of Neurology; Austin Health; Heidelberg Victoria Australia
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Abbott DF, Masterton RAJ, Archer JS, Fleming SW, Warren AEL, Jackson GD. Constructing Carbon Fiber Motion-Detection Loops for Simultaneous EEG-fMRI. Front Neurol 2015; 5:260. [PMID: 25601852 PMCID: PMC4283719 DOI: 10.3389/fneur.2014.00260] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2014] [Accepted: 11/22/2014] [Indexed: 11/13/2022] Open
Abstract
One of the most significant impediments to high-quality EEG recorded in an MRI scanner is subject motion. Availability of motion artifact sensors can substantially improve the quality of the recorded EEG. In the study of epilepsy, it can also dramatically increase the confidence that one has in discriminating true epileptiform activity from artifact. This is due both to the reduction in artifact and the ability to visually inspect the motion sensor signals when reading the EEG, revealing whether or not head motion is present. We have previously described the use of carbon fiber loops for detecting and correcting artifact in EEG acquired simultaneously with MRI. The loops, attached to the subject's head, are electrically insulated from the scalp. They provide a simple and direct measure of specific artifact that is contaminating the EEG, including both subject motion and residual artifact arising from magnetic field gradients applied during MRI. Our previous implementation was used together with a custom-built EEG-fMRI system that differs substantially from current commercially available EEG-fMRI systems. The present technical note extends this work, describing in more detail how to construct the carbon fiber motion-detection loops, and how to interface them with a commercially available simultaneous EEG-fMRI system. We hope that the information provided may help those wishing to utilize a motion-detection/correction solution to improve the quality of EEG recorded within an MRI scanner.
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Affiliation(s)
- David F Abbott
- The Florey Institute of Neuroscience and Mental Health, Austin Hospital , Melbourne, VIC , Australia ; The University of Melbourne , Melbourne, VIC , Australia
| | - Richard A J Masterton
- The Florey Institute of Neuroscience and Mental Health, Austin Hospital , Melbourne, VIC , Australia ; The University of Melbourne , Melbourne, VIC , Australia
| | - John S Archer
- The Florey Institute of Neuroscience and Mental Health, Austin Hospital , Melbourne, VIC , Australia ; The University of Melbourne , Melbourne, VIC , Australia ; Austin Hospital , Melbourne, VIC , Australia
| | - Steven W Fleming
- The Florey Institute of Neuroscience and Mental Health, Austin Hospital , Melbourne, VIC , Australia
| | - Aaron E L Warren
- The Florey Institute of Neuroscience and Mental Health, Austin Hospital , Melbourne, VIC , Australia ; The University of Melbourne , Melbourne, VIC , Australia
| | - Graeme D Jackson
- The Florey Institute of Neuroscience and Mental Health, Austin Hospital , Melbourne, VIC , Australia ; The University of Melbourne , Melbourne, VIC , Australia ; Austin Hospital , Melbourne, VIC , Australia
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Archer JS, Warren AEL, Jackson GD, Abbott DF. Conceptualizing lennox-gastaut syndrome as a secondary network epilepsy. Front Neurol 2014; 5:225. [PMID: 25400619 PMCID: PMC4214194 DOI: 10.3389/fneur.2014.00225] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 10/15/2014] [Indexed: 12/22/2022] Open
Abstract
Lennox–Gastaut Syndrome (LGS) is a category of severe, disabling epilepsy, characterized by frequent, treatment-resistant seizures, and cognitive impairment. Electroencephalography (EEG) shows characteristic generalized epileptic activity that is similar in those with lesional, genetic, or unknown causes, suggesting a common underlying mechanism. The condition typically begins in young children, leaving many severely disabled with recurring seizures throughout their adult life. Scalp EEG of the tonic seizures of LGS is characterized by a diffuse high-voltage slow transient evolving into generalized low-voltage fast activity, likely reflecting sustained fast neuronal firing over a wide cortical area. The typical interictal discharges (runs of slow spike-and-wave and bursts of generalized paroxysmal fast activity) also have a “generalized” electrical field, suggesting widespread cortical involvement. Recent brain mapping studies have begun to reveal which cortical and subcortical regions are active during these “generalized” discharges. In this critical review, we examine findings from neuroimaging studies of LGS and place these in the context of the electrical and clinical features of the syndrome. We suggest that LGS can be conceptualized as “secondary network epilepsy,” where the epileptic activity is expressed through large-scale brain networks, particularly the attention and default-mode networks. Cortical lesions, when present, appear to chronically interact with these networks to produce network instability rather than triggering each individual epileptic discharge. LGS can be considered as “secondary” network epilepsy because the epileptic manifestations of the disorder reflect the networks being driven, rather than the specific initiating process. In this review, we begin with a summation of the clinical manifestations of LGS and what this has revealed about the underlying etiology of the condition. We then undertake a systematic review of the functional neuroimaging literature in LGS, which leads us to conclude that LGS can best be conceptualized as “secondary network epilepsy.”
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Affiliation(s)
- John S Archer
- Department of Medicine, Austin Health, The University of Melbourne , Heidelberg, VIC , Australia ; Florey Institute of Neuroscience and Mental Health , Heidelberg, VIC , Australia ; Department Neurology, Austin Health , Heidelberg, VIC , Australia
| | - Aaron E L Warren
- Department of Medicine, Austin Health, The University of Melbourne , Heidelberg, VIC , Australia
| | - Graeme D Jackson
- Department of Medicine, Austin Health, The University of Melbourne , Heidelberg, VIC , Australia ; Florey Institute of Neuroscience and Mental Health , Heidelberg, VIC , Australia ; Department Neurology, Austin Health , Heidelberg, VIC , Australia
| | - David F Abbott
- Department of Medicine, Austin Health, The University of Melbourne , Heidelberg, VIC , Australia ; Florey Institute of Neuroscience and Mental Health , Heidelberg, VIC , Australia
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Archer JS, Warren AEL, Stagnitti MR, Masterton RAJ, Abbott DF, Jackson GD. Lennox-Gastaut syndrome and phenotype: secondary network epilepsies. Epilepsia 2014; 55:1245-54. [PMID: 24902608 DOI: 10.1111/epi.12682] [Citation(s) in RCA: 50] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/02/2014] [Indexed: 11/30/2022]
Abstract
OBJECTIVE Lennox-Gastaut syndrome (LGS) is a severe epilepsy phenotype with characteristic electroclinical features despite diverse etiologies. We previously found common cerebral networks involved during slow spike-and-wave (SSW) and generalized paroxysmal fast activity (PFA), characteristic interictal discharges. Some patients have a Lennox-Gastaut-like phenotype and cortical lesions. We wished to explore the interaction between cerebral networks and lesions in this group. METHODS 3 Tesla electroencephalography-functional magnetic resonance imaging (EEG-fMRI) on six subjects with Lennox-Gastaut phenotype and a structural lesion. Timings of SSW and PFA events were used in an event-related fMRI analysis, and to estimate the time course of the hemodynamic response from key regions. RESULTS (1) PFA-robust fMRI signal increases were observed in frontal and parietal association cortical areas, thalamus, and pons, with simultaneous increases in both "attention" and resting-state (default mode) networks, a highly unusual pattern. (2) SSW showed mixed increased and decreased fMRI activity, with preevent increases in association cortex and thalamus, and then prominent postevent reduction. There was decreased fMRI activity in primary cortical areas. (3) Lesion-variable fMRI increases were observed during PFA and SSW discharges. Three subjects who proceeded to lesionectomy are >1 year seizure-free. SIGNIFICANCE We conceptualize Lennox-Gastaut phenotype as a being a network epilepsy, where key cerebral networks become autonomously unstable. Epileptiform activity in Lennox-Gastaut phenotype, and by implication in LGS, appears to be amplified and expressed through association cortical areas, possibly because the attention and default-mode networks are widely interconnected, fundamental brain networks. Seizure freedom in the subjects who proceeded to lesionectomy suggests that cortical lesions are able to establish and maintain this abnormal unstable network behavior. LGS may be considered a secondary network epilepsy because the unifying epileptic manifestations of the disorder, including PFA and SSW, reflect network dysfunction, rather than the specific initiating process.
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Affiliation(s)
- John S Archer
- Department of Medicine, The University of Melbourne, Melbourne, Victoria, Australia; The Florey Institute of Neuroscience and Mental Health, Melbourne, Victoria, Australia; Austin Health, Melbourne, Victoria, Australia
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