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Traub-Weidinger T, Arbizu J, Barthel H, Boellaard R, Borgwardt L, Brendel M, Cecchin D, Chassoux F, Fraioli F, Garibotto V, Guedj E, Hammers A, Law I, Morbelli S, Tolboom N, Van Weehaeghe D, Verger A, Van Paesschen W, von Oertzen TJ, Zucchetta P, Semah F. EANM practice guidelines for an appropriate use of PET and SPECT for patients with epilepsy. Eur J Nucl Med Mol Imaging 2024; 51:1891-1908. [PMID: 38393374 PMCID: PMC11139752 DOI: 10.1007/s00259-024-06656-3] [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: 11/01/2023] [Accepted: 02/13/2024] [Indexed: 02/25/2024]
Abstract
Epilepsy is one of the most frequent neurological conditions with an estimated prevalence of more than 50 million people worldwide and an annual incidence of two million. Although pharmacotherapy with anti-seizure medication (ASM) is the treatment of choice, ~30% of patients with epilepsy do not respond to ASM and become drug resistant. Focal epilepsy is the most frequent form of epilepsy. In patients with drug-resistant focal epilepsy, epilepsy surgery is a treatment option depending on the localisation of the seizure focus for seizure relief or seizure freedom with consecutive improvement in quality of life. Beside examinations such as scalp video/electroencephalography (EEG) telemetry, structural, and functional magnetic resonance imaging (MRI), which are primary standard tools for the diagnostic work-up and therapy management of epilepsy patients, molecular neuroimaging using different radiopharmaceuticals with single-photon emission computed tomography (SPECT) and positron emission tomography (PET) influences and impacts on therapy decisions. To date, there are no literature-based praxis recommendations for the use of Nuclear Medicine (NM) imaging procedures in epilepsy. The aims of these guidelines are to assist in understanding the role and challenges of radiotracer imaging for epilepsy; to provide practical information for performing different molecular imaging procedures for epilepsy; and to provide an algorithm for selecting the most appropriate imaging procedures in specific clinical situations based on current literature. These guidelines are written and authorized by the European Association of Nuclear Medicine (EANM) to promote optimal epilepsy imaging, especially in the presurgical setting in children, adolescents, and adults with focal epilepsy. They will assist NM healthcare professionals and also specialists such as Neurologists, Neurophysiologists, Neurosurgeons, Psychiatrists, Psychologists, and others involved in epilepsy management in the detection and interpretation of epileptic seizure onset zone (SOZ) for further treatment decision. The information provided should be applied according to local laws and regulations as well as the availability of various radiopharmaceuticals and imaging modalities.
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Affiliation(s)
- Tatjana Traub-Weidinger
- Division of Nuclear Medicine, Department of Biomedical Imaging and Image-guided Therapy, Medical University of Vienna, Vienna, Austria
| | - Javier Arbizu
- Department of Nuclear Medicine, University of Navarra Clinic, Pamplona, Spain
| | - Henryk Barthel
- Department of Nuclear Medicine, Leipzig University Medical Centre, Leipzig, Germany
| | - Ronald Boellaard
- Department of Radiology and Nuclear Medicine, Amsterdam UMC, Location VUmc, Amsterdam, The Netherlands
| | - Lise Borgwardt
- Department of Clinical Physiology and Nuclear Medicine, University of Copenhagen, Blegdamsvej 9, DK-2100, RigshospitaletCopenhagen, Denmark
| | - Matthias Brendel
- Department of Nuclear Medicine, Ludwig Maximilian-University of Munich, Munich, Germany
- DZNE-German Center for Neurodegenerative Diseases, Munich, Germany
- Munich Cluster for Systems Neurology (SyNergy), Munich, Germany
| | - Diego Cecchin
- Nuclear Medicine Unit, Department of Medicine-DIMED, University-Hospital of Padova, Padova, Italy
| | - Francine Chassoux
- Université Paris-Saclay, CEA, CNRS, Inserm, BioMaps, 91401, Orsay, France
| | - Francesco Fraioli
- Institute of Nuclear Medicine, University College London (UCL), London, UK
| | - Valentina Garibotto
- Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospitals, Geneva, Switzerland
- NIMTLab, Faculty of Medicine, University of Geneva, Geneva, Switzerland
- Center for Biomedical Imaging (CIBM), Geneva, Switzerland
| | - Eric Guedj
- APHM, CNRS, Centrale Marseille, Institut Fresnel, Timone Hospital, CERIMED, Nuclear Medicine Department, Aix Marseille Univ, Marseille, France
| | - Alexander Hammers
- School of Biomedical Engineering and Imaging Sciences, Faculty of Life Sciences and Medicine, King's College London & Guy's and St Thomas' PET Centre, King's College London, London, UK
| | - Ian Law
- Department of Clinical Physiology and Nuclear Medicine, Rigshospitalet, University of Copenhagen, Blegdamsvej 9, DK-2100, Copenhagen, Denmark
| | - Silvia Morbelli
- Nuclear Medicine Unit, IRCCS Ospedale Policlinico San Martino, Department of Health Sciences (DISSAL), University of Genoa, Genoa, Italy
| | - Nelleke Tolboom
- Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht University, Utrecht, The Netherlands
| | | | - Antoine Verger
- Department of Nuclear Medicine and Nancyclotep Imaging Platform, CHRU Nancy, Université de Lorraine, IADI, INSERM U1254, Nancy, France
| | - Wim Van Paesschen
- Laboratory for Epilepsy Research, KU Leuven and Department of Neurology, University Hospitals, Leuven, Belgium
| | - Tim J von Oertzen
- Depts of Neurology 1&2, Kepler University Hospital, Johannes Kepler University, Linz, Austria
| | - Pietro Zucchetta
- Nuclear Medicine Unit, Department of Medicine-DIMED, University-Hospital of Padova, Padova, Italy
| | - Franck Semah
- Nuclear Medicine Department, University Hospital, Inserm, CHU Lille, U1172-LilNCog-Lille, F-59000, Lille, France.
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Tojima M, Shimotake A, Neshige S, Okada T, Kobayashi K, Usami K, Matsuhashi M, Honda M, Takeyama H, Hitomi T, Yoshida T, Yokoyama A, Fushimi Y, Ueno T, Yamao Y, Kikuchi T, Namiki T, Arakawa Y, Takahashi R, Ikeda A. Specific consistency score for rational selection of epilepsy resection surgery candidates. Epilepsia 2024; 65:1322-1332. [PMID: 38470337 DOI: 10.1111/epi.17945] [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: 12/08/2023] [Revised: 02/24/2024] [Accepted: 02/26/2024] [Indexed: 03/13/2024]
Abstract
OBJECTIVE Degree of indication for epilepsy surgery is determined by taking multiple factors into account. This study aimed to investigate the usefulness of the Specific Consistency Score (SCS), a proposed score for focal epilepsy to rate the indication for epilepsy focal resection. METHODS This retrospective cohort study included patients considered for resective epilepsy surgery in Kyoto University Hospital from 2011 to 2022. Plausible epileptic focus was tentatively defined. Cardinal findings were scored based on specificity and consistency with the estimated laterality and lobe. The total points represented SCS. The association between SCS and the following clinical parameters was assessed by univariate and multivariate analysis: (1) probability of undergoing resective epilepsy surgery, (2) good postoperative seizure outcome (Engel I and II or Engel I only), and (3) lobar concordance between the noninvasively estimated focus and intracranial electroencephalographic (EEG) recordings. RESULTS A total of 131 patients were evaluated. Univariate analysis revealed higher SCS in the (1) epilepsy surgery group (8.4 [95% confidence interval (CI) = 7.8-8.9] vs. 4.9 [95% CI = 4.3-5.5] points; p < .001), (2) good postoperative seizure outcome group (Engel I and II; 8.7 [95% CI = 8.2-9.3] vs. 6.4 [95% CI = 4.5-8.3] points; p = .008), and (3) patients whose focus defined by intracranial EEG matched the noninvasively estimated focus (8.3 [95% CI = 7.3-9.2] vs. 5.4 [95% CI = 3.5-7.3] points; p = .004). Multivariate analysis revealed areas under the curve of .843, .825, and .881 for Parameters 1, 2, and 3, respectively. SIGNIFICANCE SCS provides a reliable index of good indication for resective epilepsy surgery and can be easily available in many institutions not necessarily specializing in epilepsy.
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Affiliation(s)
- Maya Tojima
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Akihiro Shimotake
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Shuichiro Neshige
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
- Department of Clinical Neuroscience and Therapeutics, Hiroshima University Graduate School of Biomedical and Health Sciences, Hiroshima, Japan
| | - Tadashi Okada
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Katsuya Kobayashi
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Kiyohide Usami
- Department of Epilepsy, Movement Disorders, and Physiology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masao Matsuhashi
- Department of Epilepsy, Movement Disorders, and Physiology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Masayuki Honda
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Hirofumi Takeyama
- Department of Respiratory Care and Sleep Control Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takefumi Hitomi
- Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takeshi Yoshida
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Atsushi Yokoyama
- Department of Pediatrics, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yasutaka Fushimi
- Department of Diagnostic Imaging and Nuclear Medicine, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Tsukasa Ueno
- Department of Psychiatry, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Yukihiro Yamao
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takayuki Kikuchi
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Takao Namiki
- Department of Mathematics, Faculty of Science, Hokkaido University, Sapporo, Japan
| | - Yoshiki Arakawa
- Department of Neurosurgery, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Ryosuke Takahashi
- Department of Neurology, Kyoto University Graduate School of Medicine, Kyoto, Japan
| | - Akio Ikeda
- Department of Epilepsy, Movement Disorders, and Physiology, Kyoto University Graduate School of Medicine, Kyoto, Japan
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Geller AS, Teale P, Kronberg E, Ebersole JS. Magnetoencephalography for Epilepsy Presurgical Evaluation. Curr Neurol Neurosci Rep 2024; 24:35-46. [PMID: 38148387 DOI: 10.1007/s11910-023-01328-5] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/13/2023] [Indexed: 12/28/2023]
Abstract
PURPOSE OF THE REVIEW Magnetoencephalography (MEG) is a functional neuroimaging technique that records neurophysiology data with millisecond temporal resolution and localizes it with subcentimeter accuracy. Its capability to provide high resolution in both of these domains makes it a powerful tool both in basic neuroscience as well as clinical applications. In neurology, it has proven useful in its ability to record and localize epileptiform activity. Epilepsy workup typically begins with scalp electroencephalography (EEG), but in many situations, EEG-based localization of the epileptogenic zone is inadequate. The complementary sensitivity of MEG can be crucial in such cases, and MEG has been adopted at many centers as an important resource in building a surgical hypothesis. In this paper, we review recent work evaluating the extent of MEG influence of presurgical evaluations, novel analyses of MEG data employed in surgical workup, and new MEG instrumentation that will likely affect the field of clinical MEG. RECENT FINDINGS MEG consistently contributes to presurgical evaluation and these contributions often change the plan for epilepsy surgery. Extensive work has been done to develop new analytic methods for localizing the source of epileptiform activity with MEG. Systems using optically pumped magnetometry (OPM) have been successfully deployed to record and localize epileptiform activity. MEG remains an important noninvasive tool for epilepsy presurgical evaluation. Continued improvements in analytic methodology will likely increase the diagnostic yield of the test. Novel instrumentation with OPM may contribute to this as well, and may increase accessibility of MEG by decreasing cost.
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Affiliation(s)
- Aaron S Geller
- Department of Neurology, CU Anschutz Medical School, Aurora, CO, USA.
| | - Peter Teale
- Department of Neurology, CU Anschutz Medical School, Aurora, CO, USA
| | - Eugene Kronberg
- Department of Neurology, CU Anschutz Medical School, Aurora, CO, USA
| | - John S Ebersole
- Department of Neurology, Atlantic Neuroscience Institute, Summit, NJ, USA
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Prener M, Drejer V, Ziebell M, Jensen P, Madsen CG, Olsen S, Thomsen G, Pinborg LH, Paulson OB. Ictal and interictal SPECT with 99m Tc-HMPAO in presurgical epilepsy. II: Methodological considerations on hyper- and hypoperfusion. Epilepsia Open 2023; 8:1503-1511. [PMID: 37750050 PMCID: PMC10690685 DOI: 10.1002/epi4.12833] [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: 09/06/2023] [Accepted: 09/12/2023] [Indexed: 09/27/2023] Open
Abstract
OBJECTIVE Single-photon emission computed tomography (SPECT) with the tracer 99m Tc-HMPAO is a method to visualize the cerebral hyperperfusion during an epileptic seizure and thus localize the epileptogenic zone and seizure propagation. Subtraction of interictal from Ictal SPECT Co-registered to MRI (SISCOM) visualizes areas with relative increases in cerebral blood flow. The purpose of this retrospective study is to explore the added value of visualizing areas of hypoperfusion as well as hyperperfusion, so-called reversed SISCOM. METHODS Fifty-six patients operated for epilepsy who had been investigated with SISCOM were included in the analysis. The patients were divided into two groups based on seizure duration after tracer injection, above or below 30 s. The preoperative SISCOM description was compared to the area of resection and given a concordance score. The 56 SISCOM were recalculated visualizing also areas of hypoperfusion and again compared to the site of resection using the same scale of concordance. The reversed SISCOM were categorized into three subgroups: "Altered Conclusion," "Confirmed Conclusion," and "Adds Nothing." If an area of hyperperfusion had an area of hypoperfusion in close proximity, it was re-interpreted as noise, thus possibly altering the conclusion. If the areas of hypoperfusion were in the opposite hemisphere it was interpreted as confirming factor. Further the concordance scores from conventional SISCOM and reversed SISCOM was compared to surgical outcome to explore the difference in sensitivity, positive predictive value (PPV), and odds ratio. RESULTS In approximately half of the cases reversed SISCOM added additional value, meaning either altered the conclusion or confirmed the conclusion. The sensitivity, PPV, and odds ratio was also better in the subgroup of long, >30 s seizure duration after injection, and got worse in the group with short, <30 s seizure duration after injection. SIGNIFICANCE Adding reversed SISCOM performed better than conventional SISCOM at predicting good surgical outcome.
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Affiliation(s)
- Martin Prener
- Neurobiology Research Unit, Department of NeurologyRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Veronica Drejer
- Neurobiology Research Unit, Department of NeurologyRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Morten Ziebell
- Department of NeurosurgeryRigshospitaletCopenhagenDenmark
| | - Per Jensen
- Neurobiology Research Unit, Department of NeurologyRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Camilla Gøbel Madsen
- Department of Radiology, Centre for Functional and Diagnostic imaging and ResearchCopenhagen University Hospital Amager and HvidovreHvidovreDenmark
| | - Svitlana Olsen
- Neurobiology Research Unit, Department of NeurologyRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Gerda Thomsen
- Neurobiology Research Unit, Department of NeurologyRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Lars H. Pinborg
- Neurobiology Research Unit, Department of NeurologyRigshospitalet BlegdamsvejCopenhagenDenmark
- Epilepsy Clinic, Department of Neurology, Rigshospitalet, Copenhagen, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- Department of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
| | - Olaf B. Paulson
- Neurobiology Research Unit, Department of NeurologyRigshospitalet BlegdamsvejCopenhagenDenmark
- Department of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
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5
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Prener M, Drejer V, Ziebell M, Jensen P, Madsen CG, Olsen S, Thomsen G, Pinborg LH, Paulson OB. Ictal and interictal SPECT with 99m Tc-HMPAO in presurgical epilepsy. I: Predictive value and methodological considerations. Epilepsia Open 2023; 8:1064-1074. [PMID: 37464953 PMCID: PMC10472396 DOI: 10.1002/epi4.12786] [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: 10/07/2022] [Accepted: 06/30/2023] [Indexed: 07/20/2023] Open
Abstract
OBJECTIVE This retrospective study investigates the predictive value of ictal subtraction single-photon emission computed tomography (SPECT) co-registered to magnetic resonance imaging (MRI) (SISCOM) for successful epilepsy surgery. METHODS 57 patients examined with SISCOM as a part of epilepsy surgery evaluation were divided into two groups based on seizure duration after tracer injection (group 1: Seizure duration above or equal to 30 s, group 2: Seizure duration under 30 s). SISCOM was compared to the surgical site and categorized as good or poor concordance. Subsequently, Odds ratios (ORs) and positive predictive values (PPVs) were calculated for each group for good surgical outcome, freedom from disabling seizures. RESULTS The PPVs and ORs for good surgical outcome was 74.1% and 5.71 for group 1 and 40% and 0.22 for group 2. SISCOM had a similar positive predictive value regardless of whether the focus was in the same or neighboring lobe, but same hemisphere as the resection. CONCLUSION In conclusion, the implementation of a precise definition for a well-executed ictal SPECT scan with respect to seizure duration after injection enhances the positive predictive value (PPV) and odds ratio (OR) for successful surgical outcome, surpassing previous findings, whether the focus in resected lobe or the neighboring.
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Affiliation(s)
- Martin Prener
- Department of Neurology, Neurobiology Research UnitRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Veronica Drejer
- Department of Neurology, Neurobiology Research UnitRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Morten Ziebell
- Department of NeurosurgeryRigshospitaletCopenhagenDenmark
| | - Per Jensen
- Department of Neurology, Neurobiology Research UnitRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Camilla Gøbel Madsen
- Department of Radiology, Centre for Functional and Diagnostic imaging and ResearchCopenhagen University Hospital Amager and HvidovreHvidovreDenmark
| | - Svitlana Olsen
- Department of Neurology, Neurobiology Research UnitRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Gerda Thomsen
- Department of Neurology, Neurobiology Research UnitRigshospitalet BlegdamsvejCopenhagenDenmark
| | - Lars H. Pinborg
- Department of Neurology, Neurobiology Research UnitRigshospitalet BlegdamsvejCopenhagenDenmark
- Department of Neurology, Epilepsy ClinicRigshospitaletCopenhagenDenmark
- Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- Department of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
| | - Olaf B. Paulson
- Department of Neurology, Neurobiology Research UnitRigshospitalet BlegdamsvejCopenhagenDenmark
- Department of Clinical MedicineUniversity of CopenhagenCopenhagenDenmark
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Krishnan B, Tousseyn S, Wang ZI, Murakami H, Wu G, Burgess R, Iasemidis L, Najm I, Alexopoulos AV. Novel noninvasive identification of patient-specific epileptic networks in focal epilepsies: Linking single-photon emission computed tomography perfusion during seizures with resting-state magnetoencephalography dynamics. Hum Brain Mapp 2023; 44:1695-1710. [PMID: 36480260 PMCID: PMC9921232 DOI: 10.1002/hbm.26168] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Revised: 08/31/2022] [Accepted: 11/18/2022] [Indexed: 12/13/2022] Open
Abstract
Single-photon emission computed tomography (SPECT) during seizures and magnetoencephalography (MEG) during the interictal state are noninvasive modalities employed in the localization of the epileptogenic zone in patients with drug-resistant focal epilepsy (DRFE). The present study aims to investigate whether there exists a preferentially high MEG functional connectivity (FC) among those regions of the brain that exhibit hyperperfusion or hypoperfusion during seizures. We studied MEG and SPECT data in 30 consecutive DRFE patients who had resective epilepsy surgery. We parcellated each ictal perfusion map into 200 regions of interest (ROIs) and generated ROI time series using source modeling of MEG data. FC between ROIs was quantified using coherence and phase-locking value. We defined a generalized linear model to relate the connectivity of each ROI, ictal perfusion z score, and distance between ROIs. We compared the coefficients relating perfusion z score to FC of each ROI and estimated the connectivity within and between resected and unresected ROIs. We found that perfusion z scores were strongly correlated with the FC of hyper-, and separately, hypoperfused ROIs across patients. High interictal connectivity was observed between hyperperfused brain regions inside and outside the resected area. High connectivity was also observed between regions of ictal hypoperfusion. Importantly, the ictally hypoperfused regions had a low interictal connectivity to regions that became hyperperfused during seizures. We conclude that brain regions exhibiting hyperperfusion during seizures highlight a preferentially connected interictal network, whereas regions of ictal hypoperfusion highlight a separate, discrete and interconnected, interictal network.
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Affiliation(s)
- Balu Krishnan
- Neurological InstituteEpilepsy Center, Cleveland ClinicClevelandOhioUSA
| | - Simon Tousseyn
- Academic Center for EpileptologyKempenhaeghe and Maastricht UMC+HeezeThe Netherlands
| | - Zhong Irene Wang
- Neurological InstituteEpilepsy Center, Cleveland ClinicClevelandOhioUSA
| | - Hiroatsu Murakami
- Neurological InstituteEpilepsy Center, Cleveland ClinicClevelandOhioUSA
| | - Guiyun Wu
- Neurological InstituteEpilepsy Center, Cleveland ClinicClevelandOhioUSA
| | - Richard Burgess
- Neurological InstituteEpilepsy Center, Cleveland ClinicClevelandOhioUSA
| | - Leonidas Iasemidis
- Department of Translational NeuroscienceBarrow Neurological InstituteScottsdaleArizonaUSA
- Department of NeurologyBarrow Neurological InstituteScottsdaleArizonaUSA
| | - Imad Najm
- Neurological InstituteEpilepsy Center, Cleveland ClinicClevelandOhioUSA
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Shi LJ, Li CC, Lin YC, Ding CT, Wang YP, Zhang JC. The association of magnetoencephalography high-frequency oscillations with epilepsy types and a ripple-based method with source-level connectivity for mapping epilepsy sources. CNS Neurosci Ther 2023; 29:1423-1433. [PMID: 36815318 PMCID: PMC10068465 DOI: 10.1111/cns.14115] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2022] [Revised: 01/09/2023] [Accepted: 01/25/2023] [Indexed: 02/24/2023] Open
Abstract
OBJECTIVE To explore the association between high-frequency oscillations (HFOs) and epilepsy types and to improve the accuracy of source localization. METHODS Magnetoencephalography (MEG) ripples of 63 drug-resistant epilepsy patients were detected. Ripple rates, distribution, spatial complexity, and the clustering coefficient of ripple channels were used for the preliminary classification of lateral temporal lobe epilepsy (LTLE), mesial temporal lobe epilepsy (MTLE), and nontemporal lobe epilepsy (NTLE), mainly frontal lobe epilepsy (FLE). Furthermore, the seizure site identification was improved using the Tucker LCMV method and source-level betweenness centrality. RESULTS Ripple rates were significantly higher in MTLE than in LTLE and NTLE (p < 0.05). The LTLE and MTLE were mainly distributed in the temporal lobe, followed by the parietal lobe, occipital lobe, and frontal lobe, whereas MTLE ripples were mainly distributed in the frontal lobe, then parietal lobe and occipital lobe. Nevertheless, the NTLE ripples were primarily in the frontal lobe and partially in the occipital lobe (p < 0.05). Meanwhile, the spatial complexity of NTLE was significantly higher than that of LTLE and MTLE and was lowest in MTLE (p < 0.01). However, an opposite trend was observed for the standardized clustering coefficient compared with spatial complexity (p < 0.01). Finally, the tucker algorithm showed a higher percentage of ripples at the surgical site when the betweenness centrality was added (p < 0.01). CONCLUSION This study demonstrated that HFO rates, distribution, spatial complexity, and clustering coefficient of ripple channels varied considerably among the three epilepsy types. Additionally, tucker MEG estimation combined with ripple rates based on the source-level functional connectivity is a promising approach for presurgical epilepsy evaluation.
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Affiliation(s)
- Li-Juan Shi
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China.,Beijing Advanced Innovation Centre for Big Data-Based Precision Medicine, Beihang University, Beijing, China.,Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, China
| | - Can-Cheng Li
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China.,Beijing Advanced Innovation Centre for Big Data-Based Precision Medicine, Beihang University, Beijing, China.,Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, China
| | - Yi-Cong Lin
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China.,Brain Functional Disease and Neuromodulation of Beijing Key Laboratory, Beijing, China
| | - Cheng-Tao Ding
- Hefei Innovation Research Institute, Beihang University, Hefei, Anhui, China
| | - Yu-Ping Wang
- Department of Neurology, Xuanwu Hospital, Capital Medical University, Beijing, China.,Brain Functional Disease and Neuromodulation of Beijing Key Laboratory, Beijing, China
| | - Ji-Cong Zhang
- School of Biological Science and Medical Engineering, Beihang University, Beijing, China.,Beijing Advanced Innovation Centre for Big Data-Based Precision Medicine, Beihang University, Beijing, China.,Beijing Advanced Innovation Centre for Biomedical Engineering, Beihang University, Beijing, China.,Hefei Innovation Research Institute, Beihang University, Hefei, Anhui, China
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8
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Rampp S, Kaltenhäuser M, Müller-Voggel N, Doerfler A, Kasper BS, Hamer HM, Brandner S, Buchfelder M. MEG Node Degree for Focus Localization: Comparison with Invasive EEG. Biomedicines 2023; 11:biomedicines11020438. [PMID: 36830974 PMCID: PMC9953213 DOI: 10.3390/biomedicines11020438] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 01/23/2023] [Accepted: 01/30/2023] [Indexed: 02/05/2023] Open
Abstract
Epilepsy surgery is a viable therapy option for patients with pharmacoresistant focal epilepsies. A prerequisite for postoperative seizure freedom is the localization of the epileptogenic zone, e.g., using electro- and magnetoencephalography (EEG/MEG). Evidence shows that resting state MEG contains subtle alterations, which may add information to the workup of epilepsy surgery. Here, we investigate node degree (ND), a graph-theoretical parameter of functional connectivity, in relation to the seizure onset zone (SOZ) determined by invasive EEG (iEEG) in a consecutive series of 50 adult patients. Resting state data were subjected to whole brain, all-to-all connectivity analysis using the imaginary part of coherence. Graphs were described using parcellated ND. SOZ localization was investigated on a lobar and sublobar level. On a lobar level, all frequency bands except alpha showed significantly higher maximal ND (mND) values inside the SOZ compared to outside (ratios 1.11-1.20, alpha 1.02). Area-under-the-curve (AUC) was 0.67-0.78 for all expected alpha (0.44, ns). On a sublobar level, mND inside the SOZ was higher for all frequency bands (1.13-1.38, AUC 0.58-0.78) except gamma (1.02). MEG ND is significantly related to SOZ in delta, theta and beta bands. ND may provide new localization tools for presurgical evaluation of epilepsy surgery.
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Affiliation(s)
- Stefan Rampp
- Department of Neurosurgery, University Hospital Erlangen, 91054 Erlangen, Germany
- Department of Neurosurgery, University Hospital Halle (Saale), 06120 Halle (Saale), Germany
- Correspondence: ; Tel.: +49-9131-85-46921; Fax: +49-9131-85-34476
| | - Martin Kaltenhäuser
- Department of Neurosurgery, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Nadia Müller-Voggel
- Department of Neurosurgery, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Arnd Doerfler
- Department of Neuroradiology, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Burkhard S. Kasper
- Epilepsy Center, Department of Neurology, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Hajo M. Hamer
- Epilepsy Center, Department of Neurology, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Sebastian Brandner
- Department of Neurosurgery, University Hospital Erlangen, 91054 Erlangen, Germany
| | - Michael Buchfelder
- Department of Neurosurgery, University Hospital Erlangen, 91054 Erlangen, Germany
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Cox BC, Danoun OA, Lundstrom BN, Lagerlund TD, Wong-Kisiel LC, Brinkmann BH. EEG source imaging concordance with intracranial EEG and epileptologist review in focal epilepsy. Brain Commun 2021; 3:fcab278. [PMID: 34877536 PMCID: PMC8643498 DOI: 10.1093/braincomms/fcab278] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2020] [Revised: 09/22/2021] [Accepted: 09/23/2021] [Indexed: 12/14/2022] Open
Abstract
EEG source imaging is becoming widely used for the evaluation of medically refractory focal epilepsy. The validity of EEG source imaging has been established in several studies comparing source imaging to the surgical resection cavity and subsequent seizure freedom. We present a cohort of 87 patients and compare EEG source imaging of both ictal and interictal scalp EEG to the seizure onset zone on intracranial EEG. Concordance of EEG source imaging with intracranial EEG was determined on a sublobar level and was quantified by measuring the distance between the source imaging result and the centroid of the active seizure onset zone electrodes. The EEG source imaging results of a subgroup of 26 patients with high density 76-channel EEG were compared with the localization of three experienced epileptologists. Of 87 patients, 95% had at least one analysis concordant with intracranial EEG and 74% had complete concordance. There was a higher rate of complete concordance in temporal lobe epilepsy compared to extratemporal (89.3 and 62.8%, respectively, P = 0.015). Of the total 282 analyses performed on this cohort, higher concordance was also seen in temporal discharges (95%) compared to extratemporal (77%) (P = 0.0012), but no difference was seen comparing high-density EEG with standard (32-channel) EEG. Subgroup analysis of ictal waveforms showed greater concordance for ictal spiking, compared with rhythmic activity, paroxysmal fast activity, or obscured onset. Median distances from the dipole and maximum distributed source to a centroid of seizure onset zone electrodes were 30.0 and 32.5 mm, respectively, and the median distances from dipole and maximum distributed source to nearest seizure onset zone electrode were 22.8 and 21.7, respectively. There were significantly shorter distances in ictal spiking. There were shorter distances in patients with Engel Class 1 outcome from surgical resection compared to patients with worse outcomes. For the subgroup of 26 high-density EEG patients, EEG source localization had a significantly higher concordance (92% versus 65%), sensitivity (57% versus 35%) and positive predictive value (60% versus 36%) compared with epileptologist localization. Our study demonstrates good concordance between ictal and interictal source imaging and intracranial EEG. Temporal lobe discharges have higher concordance rates than extratemporal discharges. Importantly, this study shows that source imaging has greater agreement with intracranial EEG than visual review alone, supporting its role in surgical planning.
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Affiliation(s)
- Benjamin C Cox
- Department of Neurology, Mayo Clinic, Rochester, MN 55905, USA
| | - Omar A Danoun
- Department of Neurology, Henry Ford Hospital, Detroit, MI 48202, USA
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Kaur K, Garg A, Tripathi M, Chandra SP, Singh G, Viswanathan V, Bharti K, Singh V, Ramanujam B, Bal CS, Sharma MC, Pandey R, Vibha D, Singh RK, Mandal PK, Tripathi M. Comparative contribution of magnetoencephalography (MEG) and single-photon emission computed tomography (SPECT) in pre-operative localization for epilepsy surgery: A prospective blinded study. Seizure 2021; 86:181-188. [PMID: 33647809 DOI: 10.1016/j.seizure.2021.02.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2020] [Revised: 02/01/2021] [Accepted: 02/03/2021] [Indexed: 01/20/2023] Open
Abstract
PURPOSE The aim of this study was to compare the diagnostic value and accuracy of ictal SPECT and inter-ictal magnetoencephalography (MEG) in localizing the site for surgery in persons with drug resistant epilepsy. METHOD This was a prospective observational study. Patients expected to undergo epilepsy surgery were enrolled consecutively and the localization results from different imaging modalities were discussed in an epilepsy surgery meet. Odds ratio of good outcome (Engel I) were calculated in patients who underwent surgery in concordance with MEG and SPECT findings. Post-surgical seizure freedom lasting at least 36 months or more was considered the gold standard for determining the diagnostic output of SPECT and MEG. RESULTS MEG and SPECT were performed in 101 and 57 patients respectively. In 45 patients SPECT could not be done due to delay in injection or technical factors. The accuracy of MEG and SPECT in localizing the epileptogenic zone was found to be 74.26 % and 78.57 % respectively. The diagnostic odds ratio for Engel I surgical outcome was reported as 2.43 and 5.0 for MEG and SPECT respectively. The diagnostic odds ratio for MEG in whom SPECT was non-informative was found to be 6.57 [95 % CI 1.1, 39.24], although it was not significantly associated with good surgical outcome. MEG was useful in indicating sites for SEEG implantation. CONCLUSION SPECT was found to be non-informative for most patients, but reported better diagnostic output than MEG. MEG may be a useful alternative for patients in whom SPECT cannot be done or was non-localizing.
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Affiliation(s)
- Kirandeep Kaur
- Dept of Neurology, All India Institute of Medical Sciences, New Delhi, India; MEG Facility, National Brain Research Institute, Manesar, India
| | - Ajay Garg
- Dept of Neuroradiology, All India Institute of Medical Sciences, New Delhi, India
| | - Madhavi Tripathi
- Dept of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India
| | - Sarat P Chandra
- Dept of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India
| | - Gaurav Singh
- MEG Facility, National Brain Research Institute, Manesar, India
| | | | - Kamal Bharti
- MEG Facility, National Brain Research Institute, Manesar, India
| | - Vivek Singh
- MEG Facility, National Brain Research Institute, Manesar, India
| | - Bhargavi Ramanujam
- Dept of Neurology, All India Institute of Medical Sciences, New Delhi, India
| | - Chandra Sekhar Bal
- Dept of Neurosurgery, All India Institute of Medical Sciences, New Delhi, India
| | - Mehar Chand Sharma
- Dept of Pathology, All India Institute of Medical Sciences, New Delhi, India
| | - Ravindra Pandey
- Dept of Biostatistics, All India Institute of Medical Sciences, New Delhi, India
| | - Deepti Vibha
- Dept of Neurology, All India Institute of Medical Sciences, New Delhi, India
| | - Rajesh Kumar Singh
- Dept of Neurology, All India Institute of Medical Sciences, New Delhi, India
| | | | - Manjari Tripathi
- Dept of Neurology, All India Institute of Medical Sciences, New Delhi, India.
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Krishnan B, Tousseyn S, Nayak CS, Aung T, Kheder A, Wang ZI, Wu G, Gonzalez-Martinez J, Nair D, Burgess R, Iasemidis L, Najm I, Bulacio J, Alexopoulos AV. Neurovascular networks in epilepsy: Correlating ictal blood perfusion with intracranial electrophysiology. Neuroimage 2021; 231:117838. [PMID: 33577938 DOI: 10.1016/j.neuroimage.2021.117838] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 12/21/2020] [Accepted: 02/01/2021] [Indexed: 11/25/2022] Open
Abstract
Perfusion patterns observed in Subtraction Ictal SPECT Co-registered to MRI (SISCOM) assist in focus localization and surgical planning for patients with medically intractable focal epilepsy. While the localizing value of SISCOM has been widely investigated, its relationship to the underlying electrophysiology has not been extensively studied and is therefore not well understood. In the present study, we set to investigate this relationship in a cohort of 70 consecutive patients who underwent ictal and interictal SPECT studies and subsequent stereo-electroencephalography (SEEG) monitoring for localization of the epileptogenic focus and surgical intervention. Seizures recorded during SEEG evaluation (SEEG seizures) were matched to semiologically-similar seizures during the preoperative ictal SPECT evaluation (SPECT seizures) by comparing the semiological changes in the course of each seizure. The spectral changes of the ictal SEEG with respect to interictal ones over 7 traditional frequency bands (0.1 to 150Hz) were analyzed at each SEEG site. Neurovascular (SEEG/SPECT) relations were assessed by comparing the estimated spectral power density changes of the SEEG at each site with the perfusion changes (SISCOM z-scores) estimated from the acquired SISCOM map at that site. Across patients, a significant correlation (p<0.05) was observed between spectral changes during the SEEG seizure and SISCOM perfusion z-scores. Brain sites with high perfusion z-score exhibited higher increased SEEG power in theta to ripple frequency bands with concurrent suppression in delta and theta frequency bands compared to regions with lower perfusion z-score. The dynamics of the correlation of SISCOM perfusion and SEEG spectral power from ictal onset to seizure end and immediate postictal period were also derived. Forty-six (46) of the 70 patients underwent resective epilepsy surgery. SISCOM z-score and power increase in beta to ripple frequency bands were significantly higher in resected than non-resected sites in the patients who were seizure-free following surgery. This study provides for the first time concrete evidence that both hyper-perfusion and hypo-perfusion patterns observed in SISCOM maps have strong electrophysiological underpinnings, and that integration of the information from SISCOM and SEEG can shed light on the location and dynamics of the underlying epileptic brain networks, and thus advance our anatomo-electro-clinical understanding and approaches to targeted diagnostic and therapeutic interventions.
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Affiliation(s)
- Balu Krishnan
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA.
| | - Simon Tousseyn
- Academic Center for Epileptology, Kempenhaeghe and Maastricht UMC+, Heeze, The Netherlands
| | - Chetan Sateesh Nayak
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Thandar Aung
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Ammar Kheder
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Z Irene Wang
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Guiyun Wu
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Jorge Gonzalez-Martinez
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Dileep Nair
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Richard Burgess
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Leonidas Iasemidis
- Center for Biomedical Engineering and Rehabilitation Science, Louisiana Tech University, Ruston, LA, USA
| | - Imad Najm
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Juan Bulacio
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
| | - Andreas V Alexopoulos
- Neurological Institute, Cleveland Clinic Foundation, 9500 Euclid Ave, S51, Cleveland, OH 44195, USA
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12
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Bagić AI, Funke ME, Kirsch HE, Tenney JR, Zillgitt AJ, Burgess RC. The 10 Common Evidence-Supported Indications for MEG in Epilepsy Surgery: An Illustrated Compendium. J Clin Neurophysiol 2021; 37:483-497. [PMID: 33165222 DOI: 10.1097/wnp.0000000000000726] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Unfamiliarity with the indications for and benefits of magnetoencephalography (MEG) persists, even in the epilepsy community, and hinders its acceptance to clinical practice, despite the evidence. The wide treatment gap for patients with drug-resistant epilepsy and immense underutilization of epilepsy surgery had similar effects. Thus, educating referring physicians (epileptologists, neurologists, and neurosurgeons) both about the value of epilepsy surgery and about the potential benefits of MEG can achieve synergy and greatly improve the process of selecting surgical candidates. As a practical step toward a comprehensive educational process to benefit potential MEG users, current MEG referrers, and newcomers to MEG, the authors have elected to provide an illustrated guide to 10 everyday situations where MEG can help in the evaluation of people with drug-resistant epilepsy. They are as follows: (1) lacking or imprecise hypothesis regarding a seizure onset; (2) negative MRI with a mesial temporal onset suspected; (3) multiple lesions on MRI; (4) large lesion on MRI; (5) diagnostic or therapeutic reoperation; (6) ambiguous EEG findings suggestive of "bilateral" or "generalized" pattern; (7) intrasylvian onset suspected; (8) interhemispheric onset suspected; (9) insular onset suspected; and (10) negative (i.e., spikeless) EEG. Only their practical implementation and furtherance of personal and collective education will lead to the potentially impactful synergy of the two-MEG and epilepsy surgery. Thus, while fulfilling our mission as physicians, we must not forget that ignoring the wealth of evidence about the vast underutilization of epilepsy surgery - and about the usefulness and value of MEG in selecting surgical candidates - is far from benign neglect.
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Affiliation(s)
- Anto I Bagić
- University of Pittsburgh Comprehensive Epilepsy Center (UPCEC), Department of Neurology, University of Pittsburgh Medical Center (UPMC), Pittsburgh, Pennsylvania, U.S.A
| | - Michael E Funke
- MEG Center, McGovern Medical School, UT Houston, Houston, Texas, U.S.A
| | - Heidi E Kirsch
- UCSF Biomagnetic Imaging Laboratory, UCSF, San Francisco, California, U.S.A
| | - Jeffrey R Tenney
- MEG Center, Cincinnati Children's Hospital Medical Center , Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio, U.S.A
| | - Andrew J Zillgitt
- Department of Neurology, Beaumont Health Adult Comprehensive Epilepsy Center, Neurosicence Center, Royal Oak, Michigan, U.S.A.; and
| | - Richard C Burgess
- Magnetoencephalography Laboratory, Cleveland Clinic Epilepsy Center, Cleveland, Ohio, U.S.A
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Tierney TM, Mellor S, O'Neill GC, Holmes N, Boto E, Roberts G, Hill RM, Leggett J, Bowtell R, Brookes MJ, Barnes GR. Pragmatic spatial sampling for wearable MEG arrays. Sci Rep 2020; 10:21609. [PMID: 33303793 PMCID: PMC7729945 DOI: 10.1038/s41598-020-77589-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 11/09/2020] [Indexed: 12/16/2022] Open
Abstract
Several new technologies have emerged promising new Magnetoencephalography (MEG) systems in which the sensors can be placed close to the scalp. One such technology, Optically Pumped MEG (OP-MEG) allows for a scalp mounted system that provides measurements within millimetres of the scalp surface. A question that arises in developing on-scalp systems is: how many sensors are necessary to achieve adequate performance/spatial discrimination? There are many factors to consider in answering this question such as the signal to noise ratio (SNR), the locations and depths of the sources, density of spatial sampling, sensor gain errors (due to interference, subject movement, cross-talk, etc.) and, of course, the desired spatial discrimination. In this paper, we provide simulations which show the impact these factors have on designing sensor arrays for wearable MEG. While OP-MEG has the potential to provide high information content at dense spatial samplings, we find that adequate spatial discrimination of sources (< 1 cm) can be achieved with relatively few sensors (< 100) at coarse spatial samplings (~ 30 mm) at high SNR. After this point approximately 50 more sensors are required for every 1 mm improvement in spatial discrimination. Comparable discrimination for traditional cryogenic systems require more channels by these same metrics. We also show that sensor gain errors have the greatest impact on discrimination between deep sources at high SNR. Finally, we also examine the limitation that aliasing due to undersampling has on the effective SNR of on-scalp sensors.
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Affiliation(s)
- Tim M Tierney
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, London, WC1N 3AR, UK.
| | - Stephanie Mellor
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, London, WC1N 3AR, UK
| | - George C O'Neill
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, London, WC1N 3AR, UK
| | - Niall Holmes
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Elena Boto
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Gillian Roberts
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Ryan M Hill
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - James Leggett
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Richard Bowtell
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Matthew J Brookes
- Sir Peter Mansfield Imaging Centre, School of Physics and Astronomy, University of Nottingham, University Park, Nottingham, NG7 2RD, UK
| | - Gareth R Barnes
- Wellcome Centre for Human Neuroimaging, UCL Institute of Neurology, London, WC1N 3AR, UK
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Mir A, Baradie RA, Alnaim A, Moinuddin A, Khan MI, Jallul T, Otaibi FA, Joseph M, Dossary SA, Bashir S. Utility of single-photon emission computed tomography (SPECT) in presurgical evaluation of children: A single-center experience. Epilepsy Res 2020; 167:106445. [DOI: 10.1016/j.eplepsyres.2020.106445] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 08/10/2020] [Accepted: 08/13/2020] [Indexed: 10/23/2022]
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15
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Wang S, Tang Y, Aung T, Chen C, Katagiri M, Jones SE, Prayson RA, Krishnan B, Gonzalez-Martinez JA, Burgess RC, Najm IM, Alexopoulos AV, Wang S, Ding M, Wang ZI. Multimodal noninvasive evaluation in MRI-negative operculoinsular epilepsy. J Neurosurg 2020; 132:1334-1344. [PMID: 30978689 DOI: 10.3171/2018.12.jns182746] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 12/26/2018] [Indexed: 02/05/2023]
Abstract
OBJECTIVE Presurgical evaluation of patients with operculoinsular epilepsy and negative MRI presents major challenges. Here the authors examined the yield of noninvasive modalities such as voxel-based morphometric MRI postprocessing, FDG-PET, subtraction ictal SPECT coregistered to MRI (SISCOM), and magnetoencephalography (MEG) in a cohort of patients with operculoinsular epilepsy and negative MRI. METHODS Twenty-two MRI-negative patients were included who had focal ictal onset from the operculoinsular cortex on intracranial EEG, and underwent focal resection limited to the operculoinsular cortex. MRI postprocessing was applied to presurgical T1-weighted volumetric MRI using a morphometric analysis program (MAP). Individual and combined localization yields of MAP, FDG-PET, MEG, and SISCOM were compared with the ictal onset location on intracranial EEG. Seizure outcomes were reported at 1 year and 2 years (when available) using the Engel classification. RESULTS Ten patients (45.5%, 10/22) had operculoinsular abnormalities on MAP; 5 (23.8%, 5/21) had operculoinsular hypometabolism on FDG-PET; 4 (26.7%, 4/15) had operculoinsular hyperperfusion on SISCOM; and 6 (30.0%, 6/20) had an MEG cluster (3 tight, 3 loose) within the operculoinsular cortex. The highest yield of a 2-test combination was 59.1%, seen with MAP and SISCOM, followed by 54.5% with MAP and FDG-PET, and also 54.5% with MAP and MEG. The highest yield of a 3-test combination was 68.2%, seen with MAP, MEG, and SISCOM. The yield of the 4-test combination remained at 68.2%. When all other tests were negative or nonlocalizing, unique information was provided by MAP in 5, MEG in 1, SISCOM in 2, and FDG-PET in none of the patients. One-year follow-up was available in all patients, and showed 11 Engel class IA, 4 class IB, 4 class II, and 3 class III/IV. Two-year follow-up was available in 19 patients, and showed 9 class IA, 3 class IB, 1 class ID, 3 class II, and 3 class III/IV. CONCLUSIONS This study highlights the individual and combined values of multiple noninvasive modalities for the evaluation of nonlesional operculoinsular epilepsy. The 3-test combination of MAP, MEG, and SISCOM represented structural, interictal, and ictal localization information, and constituted the highest yield. MAP showed the highest yield of unique information when other tests were negative or nonlocalizing.
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Affiliation(s)
- Shan Wang
- 1Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
- 2Department of Neurology, West China Hospital of Sichuan University, Chengdu, China; and
| | - Yingying Tang
- 2Department of Neurology, West China Hospital of Sichuan University, Chengdu, China; and
- 3Epilepsy Center
| | | | - Cong Chen
- 1Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | | | | | | | | | | | | | | | | | - Shuang Wang
- 1Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
| | - Meiping Ding
- 1Epilepsy Center, Department of Neurology, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, China
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16
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Mouthaan BE, Rados M, Boon P, Carrette E, Diehl B, Jung J, Kimiskidis V, Kobulashvili T, Kuchukhidze G, Larsson PG, Leitinger M, Ryvlin P, Rugg-Gunn F, Seeck M, Vulliémoz S, Huiskamp G, Leijten FSS, Van Eijsden P, Trinka E, Braun KPJ. Diagnostic accuracy of interictal source imaging in presurgical epilepsy evaluation: A systematic review from the E-PILEPSY consortium. Clin Neurophysiol 2019; 130:845-855. [PMID: 30824202 DOI: 10.1016/j.clinph.2018.12.016] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2018] [Revised: 11/16/2018] [Accepted: 12/20/2018] [Indexed: 10/27/2022]
Abstract
OBJECTIVE Interictal high resolution (HR-) electric source imaging (ESI) and magnetic source imaging (MSI) are non-invasive tools to aid epileptogenic zone localization in epilepsy surgery candidates. We carried out a systematic review on the diagnostic accuracy and quality of evidence of these modalities. METHODS Embase, Pubmed and the Cochrane database were searched on 13 February 2017. Diagnostic accuracy studies taking post-surgical seizure outcome as reference standard were selected. Quality appraisal was based on the QUADAS-2 framework. RESULTS Eleven studies were included: eight MSI (n = 267), three HR-ESI (n = 127) studies. None was free from bias. This mostly involved: selection of operated patients only, interference of source imaging with surgical decision, and exclusion of indeterminate results. Summary sensitivity and specificity estimates were 82% (95% CI: 75-88%) and 53% (95% CI: 37-68%) for overall source imaging, with no statistical difference between MSI and HR-ESI. Specificity is higher when partially concordant results were included as non-concordant (p < 0.05). Inclusion of indeterminate test results as non-concordant lowered sensitivity (p < 0.05). CONCLUSIONS Source imaging has a relatively high sensitivity but low specificity for identification of the epileptogenic zone. SIGNIFICANCE We need higher quality studies allowing unbiased test evaluation to determine the added value and diagnostic accuracy of source imaging in the presurgical workup of refractory focal epilepsy.
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Affiliation(s)
- Brian E Mouthaan
- Department of (Child) Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, PO Box 85090, 3508 AB Utrecht, The Netherlands
| | - Matea Rados
- Department of (Child) Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, PO Box 85090, 3508 AB Utrecht, The Netherlands
| | - Paul Boon
- Reference Center for Refractory Epilepsy, Department of Neurology, Ghent University Hospital, Belgium
| | - Evelien Carrette
- Reference Center for Refractory Epilepsy, Department of Neurology, Ghent University Hospital, Belgium
| | - Beate Diehl
- National Hospital for Neurology and Neurosurgery, University College London Hospitals, London, United Kingdom; Department of Clinical and Experimental Epilepsy, University College, London, UK
| | - Julien Jung
- Department of Functional Neurology and Epileptology, Institute of Epilepsies (IDEE), Hospices Civils de Lyon, Lyon, France
| | - Vasilios Kimiskidis
- Laboratory of Clinical Neurophysiology, Medical School, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece
| | - Teia Kobulashvili
- Department of Neurology, Christian-Doppler University Hospital, Paracelsus Medical University, and Centre for Cognitive Neuroscience, Salzburg, Austria
| | - Giorgi Kuchukhidze
- Department of Neurology, Christian-Doppler University Hospital, Paracelsus Medical University, and Centre for Cognitive Neuroscience, Salzburg, Austria
| | - Pål G Larsson
- Department of Neurosurgery, Clinic of Surgery and Neuroscience, Oslo University Hospital, Norway
| | - Markus Leitinger
- Department of Neurology, Christian-Doppler University Hospital, Paracelsus Medical University, and Centre for Cognitive Neuroscience, Salzburg, Austria
| | - Philippe Ryvlin
- Department of Clinical Neurosciences, Lausanne University Hospital, Lausanne, Switzerland
| | - Fergus Rugg-Gunn
- National Hospital for Neurology and Neurosurgery, University College London Hospitals, London, United Kingdom; Department of Clinical and Experimental Epilepsy, University College, London, UK
| | - Margitta Seeck
- EEG and Epilepsy Unit, Department of Clinical Neurosciences, University Hospital of Geneva, Switzerland
| | - Serge Vulliémoz
- EEG and Epilepsy Unit, Department of Clinical Neurosciences, University Hospital of Geneva, Switzerland
| | - Geertjan Huiskamp
- Department of (Child) Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, PO Box 85090, 3508 AB Utrecht, The Netherlands
| | - Frans S S Leijten
- Department of (Child) Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, PO Box 85090, 3508 AB Utrecht, The Netherlands
| | - Pieter Van Eijsden
- Department of (Child) Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, PO Box 85090, 3508 AB Utrecht, The Netherlands
| | - Eugen Trinka
- Department of Neurology, Christian-Doppler University Hospital, Paracelsus Medical University, and Centre for Cognitive Neuroscience, Salzburg, Austria; Institute of Public Health, Medical Decision Making and HTA, UMIT, Private University for Health Sciences, Medical Informatics and Technology, Hall in Tyrol, Austria
| | - Kees P J Braun
- Department of (Child) Neurology and Neurosurgery, Brain Center Rudolf Magnus, University Medical Center Utrecht, PO Box 85090, 3508 AB Utrecht, The Netherlands.
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Magnetoencephalographic Mapping of Epileptic Spike Population Using Distributed Source Analysis: Comparison With Intracranial Electroencephalographic Spikes. J Clin Neurophysiol 2018; 35:339-345. [PMID: 29746391 DOI: 10.1097/wnp.0000000000000476] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
INTRODUCTION This study evaluates magnetoencephalographic (MEG) spike population as compared with intracranial electroencephalographic (IEEG) spikes using a quantitative method based on distributed source analysis. METHODS We retrospectively studied eight patients with medically intractable epilepsy who had an MEG and subsequent IEEG monitoring. Fifty MEG spikes were analyzed in each patient using minimum norm estimate. For individual spikes, each vertex in the source space was considered activated when its source amplitude at the peak latency was higher than a threshold, which was set at 50% of the maximum amplitude over all vertices. We mapped the total count of activation at each vertex. We also analyzed 50 IEEG spikes in the same manner over the intracranial electrodes and created the activation count map. The location of the electrodes was obtained in the MEG source space by coregistering postimplantation computed tomography to MRI. We estimated the MEG- and IEEG-active regions associated with the spike populations using the vertices/electrodes with a count over 25. RESULTS The activation count maps of MEG spikes demonstrated the localization associated with the spike population by variable count values at each vertex. The MEG-active region overlapped with 65 to 85% of the IEEG-active region in our patient group. CONCLUSIONS Mapping the MEG spike population is valid for demonstrating the trend of spikes clustering in patients with epilepsy. In addition, comparison of MEG and IEEG spikes quantitatively may be informative for understanding their relationship.
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Colon A, Osch MV, Buijs M, Grond J, Hillebrand A, Schijns O, Wagner G, Ossenblok P, Hofman P, Buchem M, Boon P. MEG-guided analysis of 7T-MRI in patients with epilepsy. Seizure 2018; 60:29-38. [DOI: 10.1016/j.seizure.2018.05.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2018] [Revised: 05/22/2018] [Accepted: 05/24/2018] [Indexed: 11/26/2022] Open
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Magnetoencephalography and ictal SPECT in patients with failed epilepsy surgery. Clin Neurophysiol 2018; 129:1651-1657. [DOI: 10.1016/j.clinph.2018.05.010] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2017] [Revised: 04/30/2018] [Accepted: 05/03/2018] [Indexed: 11/17/2022]
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Magnetoencephalographic Spike Analysis in Patients With Focal Cortical Dysplasia: What Defines a "Dipole Cluster"? Pediatr Neurol 2018; 83:25-31. [PMID: 29685607 PMCID: PMC5988951 DOI: 10.1016/j.pediatrneurol.2018.03.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 03/09/2018] [Indexed: 11/22/2022]
Abstract
BACKGROUND The purpose of this study is to clarify the source distribution patterns of magnetoencephalographic spikes correlated with postsurgical seizure-free outcome in pediatric patients with focal cortical dysplasia. PATIENTS AND METHODS Thirty-two patients with pathologically confirmed focal cortical dysplasia were divided into seizure-free and seizure-persistent groups according to their surgical outcomes based on Engel classification. In each patient, presurgical magnetoencephalography was reviewed. Dipole sources of magnetoencephalographic spikes were calculated according to a single dipole model. We obtained the following quantitative indices for evaluating dipole distribution: maximum distance over all pairs of dipoles, standard deviation of the distances between each dipole and the mean coordinate of all dipoles, average nearest neighbor distance, the rate of dipoles located within 10, 20, and 30 mm from the mean coordinate, and the rate of dipoles included in the resection. These indices were compared between the two patient groups. RESULTS Average nearest neighbor distance was significantly smaller in the seizure-free group than in the seizure-persistent group (P = 0.008). The rates of dipoles located within 10, 20, and 30 mm from the mean coordinate were significantly higher in the seizure-free group (P = 0.001, 0.001, 0.005, respectively). The maximum distance, standard deviation, and resection rate of dipoles did not show a significant difference between the two groups. CONCLUSIONS A spatially restricted dipole distribution of magnetoencephalographic spikes is correlated with postsurgical seizure-free outcomes in patients with focal cortical dysplasia. The distribution can be assessed by quantitative indices that are clinically useful in the presurgical evaluation of these patients.
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Stefan H, Schmitt FC. Epileptogenicity and pathology - Under consideration of ablative approaches. Epilepsy Res 2018; 142:109-112. [PMID: 29609992 DOI: 10.1016/j.eplepsyres.2018.03.019] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Revised: 03/12/2018] [Accepted: 03/25/2018] [Indexed: 11/27/2022]
Abstract
Besides resective epilepsy surgery, minimally invasive ablation using new diagnostic and therapeutic techniques recently became available. Optimal diagnostic approaches for these treatment options are discussed. The pathophysiology of epileptogenic networks differs depending on the lesion-types and location, requiring a differential use of non-invasive or invasive functional studies. In addition to the definition of epileptogenic zones, a challenge for pre-surgical investigation is the determination of three-dimensional epileptic networks to be removed.
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Affiliation(s)
- H Stefan
- Department of Neurology - Biomagnetism, University Hospital Erlangen, 10, Schwabachanlage, 91054 Erlangen, Germany.
| | - F C Schmitt
- Department of Neurology, University Hospital Magdeburg, Germany
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Feyissa AM, Britton JW, Van Gompel J, Lagerlund TL, So E, Wong-Kisiel LC, Cascino GC, Brinkman BH, Nelson CL, Watson R, Worrell GA. High density scalp EEG in frontal lobe epilepsy. Epilepsy Res 2017; 129:157-161. [PMID: 28073096 DOI: 10.1016/j.eplepsyres.2016.12.016] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2016] [Revised: 12/27/2016] [Accepted: 12/31/2016] [Indexed: 10/20/2022]
Abstract
PURPOSE Localization of seizures in frontal lobe epilepsy using the 10-20 system scalp EEG is often challenging because neocortical seizure can spread rapidly, significant muscle artifact, and the suboptimal spatial resolution for seizure generators involving mesial frontal lobe cortex. Our aim in this study was to determine the value of visual interpretation of 76 channel high density EEG (hdEEG) monitoring (10-10 system) in patients with suspected frontal lobe epilepsy, and to evaluate concordance with MRI, subtraction ictal SPECT co-registered to MRI (SISCOM), conventional EEG, and intracranial EEG (iEEG). METHODS We performed a retrospective cohort study of 14 consecutive patients who underwent hdEEG monitoring for suspected frontal lobe seizures. The gold standard for localization was considered to be iEEG. Concordance of hdEEG findings with MRI, subtraction ictal SPECT co-registered to MRI (SISCOM), conventional 10-20 EEG, and iEEG as well as correlation of hdEEG localization with surgical outcome were examined. RESULTS hdEEG localization was concordant with iEEG in 12/14 and was superior to conventional EEG 3/14 (p<0.01) and SISCOM 3/12 (p<0.01). hdEEG correctly lateralized seizure onset in 14/14 cases, compared to 9/14 (p=0.04) cases with conventional EEG. Seven patients underwent surgical resection, of whom five were seizure free. CONCLUSIONS hdEEG monitoring should be considered in patients with suspected frontal epilepsy requiring localization of epileptogenic brain. hdEEG may assist in developing a hypothesis for iEEG monitoring and could potentially augment EEG source localization.
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Affiliation(s)
- Anteneh M Feyissa
- Department of Neurology, Mayo Clinic, 4500 San Pablo Road, Jacksonville, FL, 32224, United States.
| | - Jeffrey W Britton
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Jamie Van Gompel
- Departments of Neurological Surgery, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Terrance L Lagerlund
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Elson So
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Lilly C Wong-Kisiel
- Division of Child and Adolescent Neurology, Mayo Clinic Children's Center, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Gregory C Cascino
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Benjamin H Brinkman
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Cindy L Nelson
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Robert Watson
- Department of Radiology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
| | - Gregory A Worrell
- Department of Neurology, Mayo Clinic, 200 First Street SW, Rochester, MN, 55905, United States.
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Song PP, Xiang J, Jiang L, Chen HS, Liu BK, Hu Y. Dynamic Changes in Spectral and Spatial Signatures of High Frequency Oscillations in Rat Hippocampi during Epileptogenesis in Acute and Chronic Stages. Front Neurol 2016; 7:204. [PMID: 27965619 PMCID: PMC5124575 DOI: 10.3389/fneur.2016.00204] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2016] [Accepted: 11/02/2016] [Indexed: 11/28/2022] Open
Abstract
Objective To analyze spectral and spatial signatures of high frequency oscillations (HFOs), which include ripples and fast ripples (FRs, >200 Hz) by quantitatively assessing average and peak spectral power in a rat model of different stages of epileptogenesis. Methods The lithium–pilocarpine model of temporal lobe epilepsy was used. The acute phase of epilepsy was assessed by recording intracranial electroencephalography (EEG) activity for 1 day after status epilepticus (SE). The chronic phase of epilepsy, including spontaneous recurrent seizures (SRSs), was assessed by recording EEG activity for 28 days after SE. Average and peak spectral power of five frequency bands of EEG signals in CA1, CA3, and DG regions of the hippocampus were analyzed with wavelet and digital filter. Results FRs occurred in the hippocampus in the animal model. Significant dynamic changes in the spectral power of FRS were identified in CA1 and CA3. The average spectral power of ripples increased at 20 min before SE (p < 0.05), peaked at 10 min before diazepam injection. It decreased at 10 min after diazepam (p < 0.05) and returned to baseline after 1 h. The average spectral power of FRs increased at 30 min before SE (p < 0.05) and peaked at 10 min before diazepam. It decreased at 10 min after diazepam (p < 0.05) and returned to baseline at 2 h after injection. The dynamic changes were similar between average and peak spectral power of FRs. Average and peak spectral power of both ripples and FRs in the chronic phase showed a gradual downward trend compared with normal rats 14 days after SE. Significance The spectral power of HFOs may be utilized to distinguish between normal and pathologic HFOs. Ictal average and peak spectral power of FRs were two parameters for predicting acute epileptic seizures, which could be used as a new quantitative biomarker and early warning marker of seizure. Changes in interictal HFOs power in the hippocampus at the chronic stage may be not related to seizure occurrence.
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Affiliation(s)
- Pan-Pan Song
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China; Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China; Chongqing Key Laboratory of Pediatrics, Chongqing, China; China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing, China
| | - Jing Xiang
- Department of Neurology, MEG Center, Cincinnati Children's Hospital Medical Center , Cincinnati, OH , USA
| | - Li Jiang
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China; Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China; Chongqing Key Laboratory of Pediatrics, Chongqing, China; China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing, China
| | - Heng-Sheng Chen
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China; Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China; Chongqing Key Laboratory of Pediatrics, Chongqing, China; China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing, China
| | - Ben-Ke Liu
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China; Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China; Chongqing Key Laboratory of Pediatrics, Chongqing, China; China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing, China
| | - Yue Hu
- Department of Neurology, Children's Hospital of Chongqing Medical University, Chongqing, China; Ministry of Education Key Laboratory of Child Development and Disorders, Chongqing, China; Chongqing Key Laboratory of Pediatrics, Chongqing, China; China International Science and Technology Cooperation Base of Child Development and Critical Disorders, Chongqing, China
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The role of SISCOM in preoperative evaluation for patients with epilepsy surgery: A meta-analysis. Seizure 2016; 41:43-50. [PMID: 27458682 DOI: 10.1016/j.seizure.2016.06.024] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2016] [Revised: 06/29/2016] [Accepted: 06/30/2016] [Indexed: 11/24/2022] Open
Abstract
PURPOSE To assess the specific value of subtraction ictal and inter-ictal SPECT co-registered to MRI (SISCOM) in identifying the epileptogenic zone (EZ) and predicting postoperative outcomes in epileptic surgical patients. METHOD A meta-analysis of studies published from January 1995 to June 2015 was conducted through a comprehensive literature search, and 11 studies were included. R software was first used to calculate a pooled positive rate, concordant rate and positive predictive value (PPV) for good outcomes. Stata software was then used to explore the relationship between SISCOM localization and surgical outcomes, including a subgroup analysis for extra-temporal lobe epilepsy. RESULTS The unweighted positive and concordant rates of SISCOM were 85.9% and 65.3%, respectively. In 142 MRI-negative patients, the SISCOM positive rate was 83.8%. The pooled PPV of 178 surgical patients with concordant SISCOM was 56%. In the meta-analysis of 275 surgical patients, the seizure-free odds ratio was 3.28-times higher in concordant than in non-concordant SISCOM patients [95%CI (1.90, 5.67)]. For extra-temporal lobe epilepsy, the seizure-free odds ratio was 2.44-times higher in concordant than in non-concordant SISCOM patients [95%CI (1.34, 4.43)]. CONCLUSION Our data indicate that SISCOM has moderate sensitivity in localizing the epileptogenic zone and can provide complementary information when MRI is negative. Furthermore, SISCOM localization concordant with the gold standard demonstrates slightly higher predictive value for good surgical outcomes. Further research is required to explore the influence of SISCOM localization results in temporal lobe versus extra-temporal lobe epilepsy.
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Russo A, Lallas M, Jayakar P, Miller I, Hyslop A, Dunoyer C, Resnick T, Duchowny M. The diagnostic utility of 3D-ESI rotating and moving dipole methodology in the pre-surgical evaluation of MRI-negative childhood epilepsy due to focal cortical dysplasia. Epilepsia 2016; 57:1450-7. [DOI: 10.1111/epi.13454] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 06/05/2016] [Indexed: 01/31/2023]
Affiliation(s)
- Angelo Russo
- Child Neurology Unit; IRCCS; Institute of Neurological Sciences of Bologna; Bologna Italy
| | - Matt Lallas
- Department of Neurology and Comprehensive Epilepsy Program; Brain Institute; Nicklaus Children's Hospital; Miami Florida U.S.A
| | - Prasanna Jayakar
- Department of Neurology and Comprehensive Epilepsy Program; Brain Institute; Nicklaus Children's Hospital; Miami Florida U.S.A
| | - Ian Miller
- Department of Neurology and Comprehensive Epilepsy Program; Brain Institute; Nicklaus Children's Hospital; Miami Florida U.S.A
| | - Ann Hyslop
- Department of Neurology and Comprehensive Epilepsy Program; Brain Institute; Nicklaus Children's Hospital; Miami Florida U.S.A
| | - Catalina Dunoyer
- Department of Neurology and Comprehensive Epilepsy Program; Brain Institute; Nicklaus Children's Hospital; Miami Florida U.S.A
| | - Trevor Resnick
- Department of Neurology and Comprehensive Epilepsy Program; Brain Institute; Nicklaus Children's Hospital; Miami Florida U.S.A
- Department of Neurology; University of Miami Miller School of Medicine; Miami Florida U.S.A
| | - Michael Duchowny
- Department of Neurology and Comprehensive Epilepsy Program; Brain Institute; Nicklaus Children's Hospital; Miami Florida U.S.A
- Department of Neurology; University of Miami Miller School of Medicine; Miami Florida U.S.A
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El Tahry R, Wang ZI, Kakisaka Y, Murakami H, Shibata S, Krishnan B, Kotagal P, Alexopoulos A, Burgess RC. A single tight MEG cluster may only represent a fragment of type I FCD. Clin Neurophysiol 2016; 127:2570-2. [DOI: 10.1016/j.clinph.2016.04.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Revised: 02/25/2016] [Accepted: 04/02/2016] [Indexed: 10/21/2022]
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Ahmed R, Rutka JT. The role of MEG in pre-surgical evaluation of epilepsy: current use and future directions. Expert Rev Neurother 2016; 16:795-801. [DOI: 10.1080/14737175.2016.1181544] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Raheel Ahmed
- Division of Neurosurgery, The Hospital for Sick Children, Toronto, Canada
| | - James T. Rutka
- Division of Neurosurgery, The Hospital for Sick Children, Toronto, Canada
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28
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Wang X, Zhang C, Wang Y, Hu W, Shao X, Zhang JG, Zhang K. Prognostic factors for seizure outcome in patients with MRI-negative temporal lobe epilepsy: A meta-analysis and systematic review. Seizure 2016; 38:54-62. [PMID: 27182689 DOI: 10.1016/j.seizure.2016.04.002] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2015] [Revised: 04/04/2016] [Accepted: 04/05/2016] [Indexed: 11/15/2022] Open
Abstract
PURPOSE To perform a systematic review and meta-analysis to identify predictors of postoperative seizure freedom in patients with magnetic resonance imaging (MRI)-negative temporal lobe epilepsy. METHOD Publications were screened from electronic databases (MEDLINE, EMBASE), epilepsy archives, and bibliographies of relevant articles that were written in English. We recorded all possible risk factors that might predict seizure outcome after surgery. We calculated odds ratio (OR) with corresponding 95% confidence intervals (95% CI) of predictors for postoperative seizure freedom. Heterogeneity was assessed with I(2). All meta-analyses were performed using Review Manager. RESULTS Epilepsy duration (OR=2.57, 95% CI=1.21-5.47, p<0.05, I(2)=1%) and ictal or interictal electroencephalographic anomalies precisely localized in the ipsilateral temporal lobe (OR=3.89, 95% CI=1.66-9.08, p<0.01, I(2)=0 and OR=3.38, 95% CI=1.57-7.25, p<0.05, I(2)=0, respectively) were significantly associated with a higher rate of seizure freedom after surgery. However, the positron emission tomography (PET) results were not predictive of postoperative seizure freedom (OR=2.11, 95% CI=0.95-4.65, p=0.06, I(2)=0). No significant difference in seizure freedom was observed between the positive and negative pathology groups (OR=1.36, 95% CI=0.70-2.63, p=0.36, I(2)=0). CONCLUSIONS A shorter epilepsy duration and scalp electroencephalogram (EEG) signals localized precisely in the temporal lobe predicted a better seizure outcome in patients with MRI-negative temporal lobe epilepsy.
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Affiliation(s)
- Xiu Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Chao Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Yao Wang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Wenhan Hu
- Beijing Neurosurgical Institute, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Xiaoqiu Shao
- Department of Neurology, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Jian-Guo Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China
| | - Kai Zhang
- Department of Neurosurgery, Beijing Tiantan Hospital, Capital Medical University, Tiantan xili 6, Dongcheng, Beijing 100050, China; Beijing Key Laboratory of Neurostimulation, Tiantan xili 6, Dongcheng, Beijing 100050, China.
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Pre-operative evaluation in pediatric patients with cortical dysplasia. Childs Nerv Syst 2015; 31:2225-33. [PMID: 26280628 DOI: 10.1007/s00381-015-2869-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Accepted: 08/03/2015] [Indexed: 01/12/2023]
Abstract
INTRODUCTION Focal cortical dysplasia (FCD) is an important cause of refractory seizures and catastrophic epilepsy in infants and children who had epilepsy surgery. AIMS OF THE REVIEW This manuscript will discuss age-related unique clinical characteristics in evaluation of infants and young children because the understanding of these age-related features is critical in selecting children who can benefit from epilepsy surgery. In addition, we will review the non-invasive tools available for the presurgical evaluation of children with FCD and their individual contribution to the formulation of the presurgical hypothesis.
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30
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Bagić A. Look back to leap forward: The emerging new role of magnetoencephalography (MEG) in nonlesional epilepsy. Clin Neurophysiol 2015; 127:60-66. [PMID: 26055337 DOI: 10.1016/j.clinph.2015.05.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/28/2014] [Revised: 05/02/2015] [Accepted: 05/08/2015] [Indexed: 11/25/2022]
Abstract
This review considers accumulating evidence for a new role of MEG/MSI in increasing the diagnostic yield of supposedly negative MRIs, and suggests changes in the use of MEG/MSI in presurgical epilepsy evaluations. Specific alterations in practice protocols for both the MEG practitioner (i.e. physician magnetoencephalographer) and MEG user (i.e. referring physician) are proposed that should further enhance the overall value of MEG/MSI. Although advances in MEG analysis methods will likely become increasingly assisted by computers, interpretive competency and prudent clinical judgment remain irreplaceable.
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Affiliation(s)
- Anto Bagić
- University of Pittsburgh Comprehensive Epilepsy Center (UPCEC), UPMC MEG Epilepsy Program, Department of Neurology, University of Pittsburgh Medical School, Suite 811, Kaufmann Medical Building, 3471 Fifth Ave, Pittsburgh, PA 15213, USA.
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31
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Wang ZI, Jones SE, Jaisani Z, Najm IM, Prayson RA, Burgess RC, Krishnan B, Ristic A, Wong CH, Bingaman W, Gonzalez-Martinez JA, Alexopoulos AV. Voxel-based morphometric magnetic resonance imaging (MRI) postprocessing in MRI-negative epilepsies. Ann Neurol 2015; 77:1060-75. [PMID: 25807928 DOI: 10.1002/ana.24407] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2014] [Revised: 03/02/2015] [Accepted: 03/15/2015] [Indexed: 11/06/2022]
Abstract
OBJECTIVE In the presurgical workup of magnetic resonance imaging (MRI)-negative (MRI(-) or "nonlesional") pharmacoresistant focal epilepsy (PFE) patients, discovering a previously undetected lesion can drastically change the evaluation and likely improve surgical outcome. Our study utilizes a voxel-based MRI postprocessing technique, implemented in a morphometric analysis program (MAP), to facilitate detection of subtle abnormalities in a consecutive cohort of MRI(-) surgical candidates. METHODS Included in this retrospective study was a consecutive cohort of 150 MRI(-) surgical patients. MAP was performed on T1-weighted MRI, with comparison to a scanner-specific normal database. Review and analysis of MAP were performed blinded to patients' clinical information. The pertinence of MAP(+) areas was confirmed by surgical outcome and pathology. RESULTS MAP showed a 43% positive rate, sensitivity of 0.9, and specificity of 0.67. Overall, patients with the MAP(+) region completely resected had the best seizure outcomes, followed by the MAP(-) patients, and patients who had no/partial resection of the MAP(+) region had the worst outcome (p < 0.001). Subgroup analysis revealed that visually identified subtle findings are more likely correct if also MAP(+) . False-positive rate in 52 normal controls was 2%. Surgical pathology of the resected MAP(+) areas contained mainly non-balloon-cell focal cortical dysplasia (FCD). Multiple MAP(+) regions were present in 7% of patients. INTERPRETATION MAP can be a practical and valuable tool to: (1) guide the search for subtle MRI abnormalities and (2) confirm visually identified questionable abnormalities in patients with PFE due to suspected FCD. A MAP(+) region, when concordant with the patient's electroclinical presentation, should provide a legitimate target for surgical exploration.
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Affiliation(s)
- Z Irene Wang
- Epilepsy Center, Cleveland Clinic, Cleveland, OH
| | - Stephen E Jones
- Department of Diagnostic Radiology, Mellen Imaging Center, Cleveland Clinic, Cleveland, OH
| | | | - Imad M Najm
- Epilepsy Center, Cleveland Clinic, Cleveland, OH
| | | | | | | | - Aleksandar Ristic
- Clinic of Neurology, Epilepsy Center, Clinical Center of Serbia, Belgrade, Serbia
| | - Chong H Wong
- Department of Neurology, Westmead Hospital, Sydney, Australia
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Abstract
Medically refractory epilepsy is a significant cause of morbidity and mortality in pediatric neurology. Surgical intervention has been well established as a viable treatment option in certain cases. This article reviews the process of selecting appropriate patients using the latest advances in neuroimaging and electrophysiologic techniques. It also discusses the various surgical techniques currently available, including recent advances in minimally invasive approaches.
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Wang ZI, Alexopoulos AV, Jones SE, Najm IM, Ristic A, Wong C, Prayson R, Schneider F, Kakisaka Y, Wang S, Bingaman W, Gonzalez-Martinez JA, Burgess RC. Linking MRI postprocessing with magnetic source imaging in MRI-negative epilepsy. Ann Neurol 2014; 75:759-70. [PMID: 24777960 DOI: 10.1002/ana.24169] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2014] [Revised: 04/25/2014] [Accepted: 04/26/2014] [Indexed: 11/08/2022]
Abstract
OBJECTIVE MRI-negative (MRI-) pharmacoresistant focal epilepsy (PFE) patients are most challenging for epilepsy surgical management. This study utilizes a voxel-based MRI postprocessing technique, implemented using a morphometric analysis program (MAP), aiming to facilitate detection of subtle focal cortical dysplasia (FCD) in MRI- patients. Furthermore, the study examines the concordance between MAP-identified regions and localization from magnetic source imaging (MSI). METHODS Included in this retrospective study were 25 MRI- surgical patients. MAP was performed on T1-weighted MRI, with comparison to a normal database. The pertinence of MAP+ areas was confirmed by MSI, surgical outcome and pathology. Analyses of MAP and MSI were performed blindly from patients' clinical information and independently from each other. RESULTS The detection rate of subtle changes by MAP was 48% (12/25). Once MAP+ areas were resected, patients were more likely to be seizure-free (p=0.02). There were no false positives in the 25 age-matched normal controls. Seven patients had a concordant MSI correlate. Patients in whom a concordant area was identified by both MAP and MSI had a significantly higher chance of achieving a seizure-free outcome following complete resection of this area (p=0.008). In the 9 resected MAP+ areas, pathology revealed FCD type IA in 7 and type IIB in 2. INTERPRETATION MAP shows promise in identifying subtle FCD abnormalities and increasing the diagnostic yield of conventional MRI visual analysis in presurgical evaluation of PFE. Concordant MRI postprocessing and MSI analyses may lead to the noninvasive identification of a structurally and electrically abnormal subtle lesion that can be surgically targeted.
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Affiliation(s)
- Zhong I Wang
- Epilepsy Center, Cleveland Clinic, Cleveland, OH
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Itabashi H, Jin K, Iwasaki M, Okumura E, Kanno A, Kato K, Tominaga T, Kawashima R, Nakasato N. Electro- and magneto-encephalographic spike source localization of small focal cortical dysplasia in the dorsal peri-rolandic region. Clin Neurophysiol 2014; 125:2358-63. [PMID: 24856458 DOI: 10.1016/j.clinph.2014.02.028] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2013] [Revised: 02/11/2014] [Accepted: 02/19/2014] [Indexed: 10/25/2022]
Abstract
OBJECTIVE Small focal cortical dysplasia (FCD) may be ambiguous or overlooked on magnetic resonance (MR) imaging. Source localization of EEG and magnetoencephalography (MEG) spikes was evaluated to confirm the diagnosis of small FCD. METHODS This study included 6 epilepsy patients with a single small lesion on MR imaging suggesting FCD within a single gyrus among 181 consecutive epilepsy patients admitted to our epilepsy monitoring unit over 27 months. Stereotypical interictal spikes were detected on simultaneous EEG and MEG recordings and the onset-related source of averaged spikes was estimated. RESULTS All 6 patients had unique clinical characteristics as follows: leg sensori-motor seizures in 5 patients and eye version in 1 patient; a small MR imaging lesion suggesting FCD in the dorsal peri-rolandic region, which had been overlooked until our evaluation; and both EEG and MEG dipoles were estimated adjacent to the MR imaging lesion. CONCLUSIONS Source localization of EEG and MEG spikes can confirm the diagnosis of FCD based on a single small MR imaging lesion, which was overlooked by previous examination of MR images. SIGNIFICANCE Examination of MR images should be based on spike source localization as well as seizure semiology to identify subtle MR imaging abnormalities.
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Affiliation(s)
- Hisashi Itabashi
- Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan; Department of Pediatrics, Dokkyo Medical University Koshigaya Hospital, Koshigaya, Saitama, Japan
| | - Kazutaka Jin
- Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan.
| | - Masaki Iwasaki
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Eiichi Okumura
- Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Akitake Kanno
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan
| | - Kazuhiro Kato
- Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Teiji Tominaga
- Department of Neurosurgery, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
| | - Ryuta Kawashima
- Department of Functional Brain Imaging, Institute of Development, Aging and Cancer, Tohoku University, Sendai, Miyagi, Japan
| | - Nobukazu Nakasato
- Department of Epileptology, Tohoku University Graduate School of Medicine, Sendai, Miyagi, Japan
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Pittau F, Grouiller F, Spinelli L, Seeck M, Michel CM, Vulliemoz S. The role of functional neuroimaging in pre-surgical epilepsy evaluation. Front Neurol 2014. [PMID: 24715886 DOI: 10.3389/fneur.2014.00031.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The prevalence of epilepsy is about 1% and one-third of cases do not respond to medical treatment. In an eligible subset of patients with drug-resistant epilepsy, surgical resection of the epileptogenic zone is the only treatment that can possibly cure the disease. Non-invasive techniques provide information for the localization of the epileptic focus in the majority of cases, whereas in others invasive procedures are required. In the last years, non-invasive neuroimaging techniques, such as simultaneous recording of functional magnetic resonance imaging and electroencephalogram (EEG-fMRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), electric and magnetic source imaging (MSI, ESI), spectroscopy (MRS), have proved their usefulness in defining the epileptic focus. The combination of these functional techniques can yield complementary information and their concordance is crucial for guiding clinical decision, namely the planning of invasive EEG recordings or respective surgery. The aim of this review is to present these non-invasive neuroimaging techniques, their potential combination, and their role in the pre-surgical evaluation of patients with pharmaco-resistant epilepsy.
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Affiliation(s)
- Francesca Pittau
- Presurgical Epilepsy Evaluation Unit, Neurology Department, University Hospital of Geneva , Geneva , Switzerland
| | - Frédéric Grouiller
- Department of Radiology and Medical Informatics, University Hospital of Geneva , Geneva , Switzerland
| | - Laurent Spinelli
- Presurgical Epilepsy Evaluation Unit, Neurology Department, University Hospital of Geneva , Geneva , Switzerland
| | - Margitta Seeck
- Presurgical Epilepsy Evaluation Unit, Neurology Department, University Hospital of Geneva , Geneva , Switzerland
| | - Christoph M Michel
- Functional Brain Mapping Laboratory, Department of Fundamental Neurosciences, University of Geneva , Geneva , Switzerland
| | - Serge Vulliemoz
- Presurgical Epilepsy Evaluation Unit, Neurology Department, University Hospital of Geneva , Geneva , Switzerland
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Pittau F, Grouiller F, Spinelli L, Seeck M, Michel CM, Vulliemoz S. The role of functional neuroimaging in pre-surgical epilepsy evaluation. Front Neurol 2014; 5:31. [PMID: 24715886 PMCID: PMC3970017 DOI: 10.3389/fneur.2014.00031] [Citation(s) in RCA: 66] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2013] [Accepted: 03/06/2014] [Indexed: 12/25/2022] Open
Abstract
The prevalence of epilepsy is about 1% and one-third of cases do not respond to medical treatment. In an eligible subset of patients with drug-resistant epilepsy, surgical resection of the epileptogenic zone is the only treatment that can possibly cure the disease. Non-invasive techniques provide information for the localization of the epileptic focus in the majority of cases, whereas in others invasive procedures are required. In the last years, non-invasive neuroimaging techniques, such as simultaneous recording of functional magnetic resonance imaging and electroencephalogram (EEG-fMRI), positron emission tomography (PET), single photon emission computed tomography (SPECT), electric and magnetic source imaging (MSI, ESI), spectroscopy (MRS), have proved their usefulness in defining the epileptic focus. The combination of these functional techniques can yield complementary information and their concordance is crucial for guiding clinical decision, namely the planning of invasive EEG recordings or respective surgery. The aim of this review is to present these non-invasive neuroimaging techniques, their potential combination, and their role in the pre-surgical evaluation of patients with pharmaco-resistant epilepsy.
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Affiliation(s)
- Francesca Pittau
- Presurgical Epilepsy Evaluation Unit, Neurology Department, University Hospital of Geneva , Geneva , Switzerland
| | - Frédéric Grouiller
- Department of Radiology and Medical Informatics, University Hospital of Geneva , Geneva , Switzerland
| | - Laurent Spinelli
- Presurgical Epilepsy Evaluation Unit, Neurology Department, University Hospital of Geneva , Geneva , Switzerland
| | - Margitta Seeck
- Presurgical Epilepsy Evaluation Unit, Neurology Department, University Hospital of Geneva , Geneva , Switzerland
| | - Christoph M Michel
- Functional Brain Mapping Laboratory, Department of Fundamental Neurosciences, University of Geneva , Geneva , Switzerland
| | - Serge Vulliemoz
- Presurgical Epilepsy Evaluation Unit, Neurology Department, University Hospital of Geneva , Geneva , Switzerland
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Abstract
Purpose of review This review examines recent reports on the use of advanced techniques to map the regions and networks involved during focal epileptic seizure generation in humans. Recent findings A number of imaging techniques are capable of providing new localizing information on the ictal processes and epileptogenic zone. Evaluating the clinical utility of these findings has been mainly performed through post-hoc comparison with the findings of invasive EEG and ictal single-photon emission computed tomography, using postsurgical seizure reduction as the main outcome measure. Added value has been demonstrated in MRI-negative cases. Improved understanding of the human ictiogenic processes and the focus vs. network hypothesis is likely to result from the application of multimodal techniques that combine electrophysiological, semiological, and whole-brain coverage of brain activity changes. Summary On the basis of recent research in the field of neuroimaging, several novel imaging modalities have been improved and developed to provide information about the localization of epileptic foci.
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Elwan SA, Wu G, Huang SSL, Najm IM, So NK. Ictal single photon emission computed tomography in epileptic auras. Epilepsia 2013; 55:133-6. [DOI: 10.1111/epi.12475] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 10/13/2013] [Indexed: 11/27/2022]
Affiliation(s)
- Sherif A. Elwan
- Epilepsy Center; Neurological Institute; Cleveland Clinic; Cleveland Ohio U.S.A
- Department of Neurology; Ain Shams University; Cairo Egypt
| | - Guiyun Wu
- Department of Nuclear Medicine; Cleveland Clinic; Cleveland Ohio U.S.A
| | - Steve S. L. Huang
- Department of Nuclear Medicine; Cleveland Clinic; Cleveland Ohio U.S.A
| | - Imad M. Najm
- Epilepsy Center; Neurological Institute; Cleveland Clinic; Cleveland Ohio U.S.A
| | - Norman K. So
- Epilepsy Center; Neurological Institute; Cleveland Clinic; Cleveland Ohio U.S.A
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