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Banjac S, Roger E, Cousin E, Mosca C, Minotti L, Krainik A, Kahane P, Baciu M. Mapping of Language-and-Memory Networks in Patients With Temporal Lobe Epilepsy by Using the GE2REC Protocol. Front Hum Neurosci 2022; 15:752138. [PMID: 35069148 PMCID: PMC8772037 DOI: 10.3389/fnhum.2021.752138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Accepted: 12/13/2021] [Indexed: 11/17/2022] Open
Abstract
Preoperative mapping of language and declarative memory functions in temporal lobe epilepsy (TLE) patients is essential since they frequently encounter deterioration of these functions and show variable degrees of cerebral reorganization. Due to growing evidence on language and declarative memory interdependence at a neural and neuropsychological level, we propose the GE2REC protocol for interactive language-and-memory network (LMN) mapping. GE2REC consists of three inter-related tasks, sentence generation with implicit encoding (GE) and two recollection (2REC) memory tasks: recognition and recall. This protocol has previously been validated in healthy participants, and in this study, we showed that it also maps the LMN in the left TLE (N = 18). Compared to healthy controls (N = 19), left TLE (LTLE) showed widespread inter- and intra-hemispheric reorganization of the LMN through reduced activity of regions engaged in the integration and the coordination of this meta-network. We also illustrated how this protocol could be implemented in clinical practice individually by presenting two case studies of LTLE patients who underwent efficient surgery and became seizure-free but showed different cognitive outcomes. This protocol can be advantageous for clinical practice because it (a) is short and easy to perform; (b) allows brain mapping of essential cognitive functions, even at an individual level; (c) engages language-and-memory interaction allowing to evaluate the integrative processes within the LMN; (d) provides a more comprehensive assessment by including both verbal and visual modalities, as well as various language and memory processes. Based on the available postsurgical data, we presented preliminary results obtained with this protocol in LTLE patients that could potentially inform the clinical practice. This implies the necessity to further validate the potential of GE2REC for neurosurgical planning, along with two directions, guiding resection and describing LMN neuroplasticity at an individual level.
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Affiliation(s)
- Sonja Banjac
- Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France
| | - Elise Roger
- Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France
| | - Emilie Cousin
- Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France
- Université Grenoble Alpes, UMS IRMaGe CHU Grenoble, Grenoble, France
| | - Chrystèle Mosca
- Université Grenoble Alpes, Grenoble Institute of Neuroscience ‘Synchronisation et modulation des réseaux neuronaux dans l’épilepsie’ & Neurology Department, Grenoble, France
| | - Lorella Minotti
- Université Grenoble Alpes, Grenoble Institute of Neuroscience ‘Synchronisation et modulation des réseaux neuronaux dans l’épilepsie’ & Neurology Department, Grenoble, France
| | - Alexandre Krainik
- Université Grenoble Alpes, UMS IRMaGe CHU Grenoble, Grenoble, France
| | - Philippe Kahane
- Université Grenoble Alpes, Grenoble Institute of Neuroscience ‘Synchronisation et modulation des réseaux neuronaux dans l’épilepsie’ & Neurology Department, Grenoble, France
| | - Monica Baciu
- Université Grenoble Alpes, CNRS LPNC UMR 5105, Grenoble, France
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Ohlerth AK, Bastiaanse R, Negwer C, Sollmann N, Schramm S, Schröder A, Krieg SM. Benefit of Action Naming Over Object Naming for Visualization of Subcortical Language Pathways in Navigated Transcranial Magnetic Stimulation-Based Diffusion Tensor Imaging-Fiber Tracking. Front Hum Neurosci 2021; 15:748274. [PMID: 34803634 PMCID: PMC8603927 DOI: 10.3389/fnhum.2021.748274] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 10/11/2021] [Indexed: 11/13/2022] Open
Abstract
Visualization of functionally significant subcortical white matter fibers is needed in neurosurgical procedures in order to avoid damage to the language network during resection. In an effort to achieve this, positive cortical points revealed during preoperative language mapping with navigated transcranial magnetic stimulation (nTMS) can be employed as regions of interest (ROIs) for diffusion tensor imaging (DTI) fiber tracking. However, the effect that the use of different language tasks has on nTMS mapping and subsequent DTI-fiber tracking remains unexplored. The visualization of ventral stream tracts with an assumed lexico-semantic role may especially benefit from ROIs delivered by the lexico-semantically demanding verb task, Action Naming. In a first step, bihemispheric nTMS language mapping was administered in 18 healthy participants using the standard task Object Naming and the novel task Action Naming to trigger verbs in a small sentence context. Cortical areas in which nTMS induced language errors were identified as language-positive cortical sites. In a second step, nTMS-based DTI-fiber tracking was conducted using solely these language-positive points as ROIs. The ability of the two tasks’ ROIs to visualize the dorsal tracts Arcuate Fascicle and Superior Longitudinal Fascicle, the ventral tracts Inferior Longitudinal Fascicle, Uncinate Fascicle, and Inferior Fronto-Occipital Fascicle, the speech-articulatory Cortico-Nuclear Tract, and interhemispheric commissural fibers was compared in both hemispheres. In the left hemisphere, ROIs of Action Naming led to a significantly higher fraction of overall visualized tracts, specifically in the ventral stream’s Inferior Fronto-Occipital and Inferior Longitudinal Fascicle. No difference was found between tracking with Action Naming vs. Object Naming seeds for dorsal stream tracts, neither for the speech-articulatory tract nor the inter-hemispheric connections. While the two tasks appeared equally demanding for phonological-articulatory processes, ROI seeding through the task Action Naming seemed to better visualize lexico-semantic tracts in the ventral stream. This distinction was not evident in the right hemisphere. However, the distribution of tracts exposed was, overall, mirrored relative to those in the left hemisphere network. In presurgical practice, mapping and tracking of language pathways may profit from these findings and should consider inclusion of the Action Naming task, particularly for lesions in ventral subcortical regions.
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Affiliation(s)
- Ann-Katrin Ohlerth
- Center for Language and Cognition Groningen, University of Groningen, Groningen, Netherlands.,International Doctorate for Experimental Approaches to Language and Brain (IDEALAB), University of Groningen, Groningen, Netherlands
| | - Roelien Bastiaanse
- Center for Language and Brain, National Research University Higher School of Economics, Moscow, Russia
| | - Chiara Negwer
- Department of Neurosurgery, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Nico Sollmann
- Department of Diagnostic and Interventional Neuroradiology, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.,TUM-Neuroimaging Center, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.,Department of Diagnostic and Interventional Radiology, University Hospital Ulm, Ulm, Germany
| | - Severin Schramm
- Department of Neurosurgery, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Axel Schröder
- Department of Neurosurgery, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
| | - Sandro M Krieg
- Department of Neurosurgery, School of Medicine, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany.,TUM-Neuroimaging Center, Klinikum Rechts der Isar, Technical University of Munich, Munich, Germany
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3
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Usui K, Shinozaki J, Usui N, Terada K, Matsuda K, Kondo A, Tottori T, Nagamine T, Inoue Y. Retained absolute pitch after selective amygdalohippocampectomy. Epilepsy Behav Rep 2020; 14:100378. [PMID: 32984806 PMCID: PMC7494675 DOI: 10.1016/j.ebr.2020.100378] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2020] [Revised: 06/13/2020] [Accepted: 06/19/2020] [Indexed: 11/17/2022] Open
Abstract
This study assessed the pre-operative chronic condition and effect of epilepsy surgery in a 21-year-old Japanese woman with drug-resistant right temporal lobe epilepsy (TLE). For this patient, it was crucially important to preserve language and her music capabilities, including absolute pitch (AP), which is found in the general population at less than 0.1%. The patient became seizure free, and her AP capability was preserved after selective amygdalohippocampectomy in the non-dominant right hemisphere. Most of the neuropsychological test (WAIS-III and WMS-R) scores remained in the normal range, except for low scores in verbal memory and markedly improved attention/concentration index. The patient's pre- and postoperative brain function related to language and music capabilities were investigated using functional magnetic resonance imaging (fMRI) based on two language tasks and a music task (listening to melodies). While task performance was similar in pre- and postoperative examinations, her brain activation patterns markedly differed. The most striking difference was during the music task: areas with significant activation existed in the bilateral frontal and temporal lobes before surgery, whereas postoperative activation was confined to a very limited region in the left angular gyrus. The authors speculate that the surgery triggered some change in functional organization in the brain, which contributed to preserving her capabilities. A music student with drug-resistant temporal lobe epilepsy (TLE) became seizure free. Postoperative evaluation exhibited almost stable AP ability and cognitive function. Brain activation patterns on fMRI showed a notable change after surgery. Surgery possibly triggered some change in functional organization of the brain. Change in functional organization possibly contributed to preserving the capabilities.
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Affiliation(s)
- Keiko Usui
- Department of Systems Neuroscience, School of Medicine, Sapporo Medical University, S1W17, Chuo-ku, Sapporo, Hokkaido 060-8556, Japan
- Corresponding author.
| | - Jun Shinozaki
- Department of Systems Neuroscience, School of Medicine, Sapporo Medical University, S1W17, Chuo-ku, Sapporo, Hokkaido 060-8556, Japan
| | - Naotaka Usui
- National Epilepsy Center, NHO Shizuoka Institute of Epilepsy and Neurological Disorders, Urushiyama 886, Aoi-ku, Shizuoka 420-8688, Japan
| | - Kiyohito Terada
- National Epilepsy Center, NHO Shizuoka Institute of Epilepsy and Neurological Disorders, Urushiyama 886, Aoi-ku, Shizuoka 420-8688, Japan
| | - Kazumi Matsuda
- National Epilepsy Center, NHO Shizuoka Institute of Epilepsy and Neurological Disorders, Urushiyama 886, Aoi-ku, Shizuoka 420-8688, Japan
| | - Akihiko Kondo
- National Epilepsy Center, NHO Shizuoka Institute of Epilepsy and Neurological Disorders, Urushiyama 886, Aoi-ku, Shizuoka 420-8688, Japan
| | - Takayasu Tottori
- National Epilepsy Center, NHO Shizuoka Institute of Epilepsy and Neurological Disorders, Urushiyama 886, Aoi-ku, Shizuoka 420-8688, Japan
| | - Takashi Nagamine
- Department of Systems Neuroscience, School of Medicine, Sapporo Medical University, S1W17, Chuo-ku, Sapporo, Hokkaido 060-8556, Japan
| | - Yushi Inoue
- National Epilepsy Center, NHO Shizuoka Institute of Epilepsy and Neurological Disorders, Urushiyama 886, Aoi-ku, Shizuoka 420-8688, Japan
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Bear JJ, Chapman KE, Tregellas JR. The epileptic network and cognition: What functional connectivity is teaching us about the childhood epilepsies. Epilepsia 2019; 60:1491-1507. [PMID: 31247129 PMCID: PMC7175745 DOI: 10.1111/epi.16098] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2019] [Revised: 05/09/2019] [Accepted: 06/05/2019] [Indexed: 12/13/2022]
Abstract
Our objective was to summarize and evaluate the rapidly expanding body of literature studying functional connectivity in childhood epilepsy. In the self-limited childhood epilepsies, awareness of cognitive comorbidities has been steadily increasing, and recent advances in our understanding of the network effects of these disorders promise insights into the underlying neurobiology. We reviewed publications addressing functional connectivity in children with epilepsy with an emphasis on studies of children with self-limited childhood epilepsies. The majority of studies have been published in the past 10 years and predominantly examine childhood epilepsy with centrotemporal spikes and childhood absence epilepsy. Cognitive network alterations are commonly observed across the childhood epilepsies. Some of these effects appear to be nonspecific to epilepsy syndrome or even to category of neurological disorder. Other patterns, such as changes in the connectivity of cortical language areas in childhood epilepsy with centrotemporal spikes, provide clues to the underlying cognitive deficits seen in affected children. The literature to date is dominated by general observations of connectivity patterns without a priori hypotheses. These data-driven studies build an important foundation for hypothesis generation and are already providing useful insights into the neuropathology of the childhood epilepsies. Future work should emphasize hypothesis-driven approaches and rigorous clinical correlations to better understand how the knowledge of network alterations can be applied to guidance and treatment for the children in our clinics.
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Affiliation(s)
- Joshua J Bear
- Department of Pediatrics, Section of Neurology, Children’s Hospital Colorado
- Department of Pediatrics, University of Colorado Anschutz Medical Campus
| | - Kevin E Chapman
- Department of Pediatrics, Section of Neurology, Children’s Hospital Colorado
- Department of Pediatrics, University of Colorado Anschutz Medical Campus
| | - Jason R Tregellas
- Department of Psychiatry, University of Colorado Anschutz Medical Campus
- Research Service, Rocky Mountain Regional VA Medical Center
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Schmid E, Thomschewski A, Taylor A, Zimmermann G, Kirschner M, Kobulashvili T, Brigo F, Rados M, Helmstaedter C, Braun K, Trinka E. Diagnostic accuracy of functional magnetic resonance imaging, Wada test, magnetoencephalography, and functional transcranial Doppler sonography for memory and language outcome after epilepsy surgery: A systematic review. Epilepsia 2018; 59:2305-2317. [PMID: 30374948 DOI: 10.1111/epi.14588] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Accepted: 09/27/2018] [Indexed: 12/01/2022]
Abstract
OBJECTIVE The European Union-funded E-PILEPSY project was launched to develop guidelines and recommendations for epilepsy surgery. In this systematic review, we aimed to assess the diagnostic accuracy of functional magnetic resonance imaging (fMRI), Wada test, magnetoencephalography (MEG), and functional transcranial Doppler sonography (fTCD) for memory and language decline after surgery. METHODS The literature search was conducted using PubMed, Embase, and CENTRAL. The diagnostic accuracy was expressed in terms of sensitivity and specificity for postoperative language or memory decline, as determined by pre- and postoperative neuropsychological assessments. If two or more estimates of sensitivity or specificity were extracted from a study, two meta-analyses were conducted, using the maximum ("best case") and the minimum ("worst case") of the extracted estimates, respectively. RESULTS Twenty-eight papers were eligible for data extraction and further analysis. All tests for heterogeneity were highly significant, indicating large between-study variability (P < 0.001). For memory outcomes, meta-analyses were conducted for Wada tests (n = 17) using both memory and language laterality quotients. In the best case, meta-analyses yielded a sensitivity estimate of 0.79 (95% confidence interval [CI] = 0.67-0.92) and a specificity estimate of 0.65 (95% CI = 0.47-0.83). For the worst case, meta-analyses yielded a sensitivity estimate of 0.65 (95% CI = 0.48-0.82) and a specificity estimate of 0.46 (95% CI = 0.28-0.65). The overall quality of evidence, which was assessed using Grading of Recommendations Assessment, Development, and Evaluation methodology, was rated as very low. Meta-analyses concerning diagnostic accuracy of fMRI, fTCD, and MEG were not feasible due to small numbers of studies (fMRI, n = 4; fTCD, n = 1; MEG, n = 0). This also applied to studies concerning language outcomes (Wada test, n = 6; fMRI, n = 2; fTCD, n = 1; MEG, n = 0). SIGNIFICANCE Meta-analyses could only be conducted in a few subgroups for the Wada test with low-quality evidence. Thus, more evidence from high-quality studies and improved data reporting are required. Moreover, the large between-study heterogeneity underlines the necessity for more homogeneous and thus comparable studies in future research.
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Affiliation(s)
- Elisabeth Schmid
- Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria.,Department of Psychology, Paris Lodron University of Salzburg, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg, Salzburg, Austria
| | - Aljoscha Thomschewski
- Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria.,Department of Psychology, Paris Lodron University of Salzburg, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg, Salzburg, Austria.,Center for Cognitive Neuroscience, Salzburg, Austria
| | - Alexandra Taylor
- Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria.,Department of Psychology, Paris Lodron University of Salzburg, Salzburg, Austria
| | - Georg Zimmermann
- Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg, Salzburg, Austria.,Department of Mathematics, Paris Lodron University of Salzburg, Salzburg, Austria
| | - Margarita Kirschner
- Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria
| | - Teia Kobulashvili
- Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria
| | - Francesco Brigo
- Department of Neurosciences, Biomedicine and Movement Sciences, University of Verona, Verona, Italy.,Department of Neurology, Franz Tappeiner Hospital, Merano, Italy
| | - Matea Rados
- Department of Child Neurology, University Medical Center, Utrecht, The Netherlands
| | | | - Kees Braun
- Department of Child Neurology, University Medical Center, Utrecht, The Netherlands
| | - Eugen Trinka
- Department of Neurology, Christian Doppler Medical Center, Paracelsus Medical University, Salzburg, Austria.,Spinal Cord Injury and Tissue Regeneration Center Salzburg, Salzburg, Austria.,Center for Cognitive Neuroscience, Salzburg, Austria
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Piervincenzi C, Petrilli A, Marini A, Caulo M, Committeri G, Sestieri C. Multimodal assessment of hemispheric lateralization for language and its relevance for behavior. Neuroimage 2016; 142:351-370. [DOI: 10.1016/j.neuroimage.2016.08.018] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2016] [Revised: 08/08/2016] [Accepted: 08/09/2016] [Indexed: 10/21/2022] Open
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Sollmann N, Negwer C, Tussis L, Hauck T, Ille S, Maurer S, Giglhuber K, Bauer JS, Ringel F, Meyer B, Krieg SM. Interhemispheric connectivity revealed by diffusion tensor imaging fiber tracking derived from navigated transcranial magnetic stimulation maps as a sign of language function at risk in patients with brain tumors. J Neurosurg 2016; 126:222-233. [PMID: 27035166 DOI: 10.3171/2016.1.jns152053] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVE Resection of brain tumors in language-eloquent areas entails the risk of postoperative aphasia. It has been demonstrated via navigated transcranial magnetic stimulation (nTMS) that language function can partially shift to the unaffected hemisphere due to tumor-induced plasticity. Therefore, this study was designed to evaluate whether interhemispheric connectivity (IC) detected by nTMS-based diffusion tensor imaging-fiber tracking (DTI-FT) can be used to predict surgery-related aphasia in patients with brain tumors. METHODS Thirty-eight patients with left-sided perisylvian brain lesions underwent cortical language mapping of both hemispheres by nTMS prior to awake surgery. Then, nTMS-based DTI-FT was conducted with a fractional anisotropy (FA) of 0.01 and 0.2 to visualize nTMS-based IC. Receiver operating characteristics were calculated for the prediction of a postoperative (irrespective of the preoperative state) and a new surgery-related aphasia by the presence of detectable IC. RESULTS Language mapping by nTMS was possible in all patients. Seventeen patients (44.7%) suffered from surgery-related worsening of language performance (transient aphasia according to 3-month follow-up in 16 subjects [42.1%]; new permanent aphasia according to 3-month follow-up in 1 patient [2.6%]). Regarding the correlation of aphasia to nTMS-based IC, statistically significant differences were revealed for both evaluated FA values. However, better results were observed for tractography with an FA of 0.2, which led to a specificity of 93% (postoperative aphasia) and 90% (surgery-related aphasia). For postoperative aphasia, the corresponding OR was 0.1282 (95% CI 0.0143-1.1520), and for surgery-related aphasia the OR was 0.1184 (95% CI 0.0208-0.6754). CONCLUSIONS According to these results, IC detected by preoperative nTMS-based DTI-FT might be regarded as a risk factor for surgery-related aphasia, with a specificity of up to 93%. However, because the majority of enrolled patients suffered from transient aphasia postoperatively, it has to be evaluated whether this approach distinctly leads to similar results among patients with permanent language deficits. Despite this restriction, this approach might contribute to individualized patient consultation prior to tumor resection in clinical practice.
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Affiliation(s)
- Nico Sollmann
- Department of Neurosurgery.,TUM-Neuroimaging Center, and
| | - Chiara Negwer
- Department of Neurosurgery.,TUM-Neuroimaging Center, and
| | - Lorena Tussis
- Department of Neurosurgery.,TUM-Neuroimaging Center, and
| | - Theresa Hauck
- Department of Neurosurgery.,TUM-Neuroimaging Center, and
| | - Sebastian Ille
- Department of Neurosurgery.,TUM-Neuroimaging Center, and
| | | | | | - Jan S Bauer
- Section of Neuroradiology, Department of Radiology, Klinikum rechts der Isar, Technische Universität München, Germany
| | | | | | - Sandro M Krieg
- Department of Neurosurgery.,TUM-Neuroimaging Center, and
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Resting-state functional connectivity in epilepsy: growing relevance for clinical decision making. Curr Opin Neurol 2015; 28:158-65. [PMID: 25734954 DOI: 10.1097/wco.0000000000000178] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
PURPOSE OF REVIEW Seizures produce dysfunctional, maladaptive networks, making functional connectivity an ideal technique for identifying complex brain effects of epilepsy. We review the current status of resting-state functional connectivity (rsFC) research, highlighting its potential added value to epilepsy surgery programs. RECENT FINDINGS RsFC research has demonstrated that the brain impact of seizures goes beyond the epileptogenic zone, changing connectivity patterns in widespread cortical regions. There is evidence for abnormal connectivity, but the degree to which these represent adaptive or maladaptive plasticity responses is unclear. Empirical associations with cognitive performance and psychiatric symptoms have helped understand deleterious impacts of seizures outside the epileptogenic zone. Studies in the prediction of outcome suggest that there are identifiable presurgical patterns of functional connectivity associated with a greater likelihood of positive cognitive or seizure outcomes. SUMMARY The role of rsFC remains limited in most clinical settings, but shows great promise for identifying epileptic circuits and foci, predicting outcomes following surgery, and explaining cognitive deficits and psychiatric symptoms of epilepsy. RsFC has demonstrated that even focal epilepsies constitute a network and brain systems disorder. By providing a tool to both identify and characterize the brain network impact of epileptiform activity, rsFC can make a strong contribution to presurgical algorithms in epilepsy.
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Gleichgerrcht E, Kocher M, Bonilha L. Connectomics and graph theory analyses: Novel insights into network abnormalities in epilepsy. Epilepsia 2015; 56:1660-8. [DOI: 10.1111/epi.13133] [Citation(s) in RCA: 79] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/04/2015] [Indexed: 12/31/2022]
Affiliation(s)
- Ezequiel Gleichgerrcht
- Department of Neurology; Medical University of South Carolina; Charleston South Carolina U.S.A
| | - Madison Kocher
- Department of Neurology; Medical University of South Carolina; Charleston South Carolina U.S.A
| | - Leonardo Bonilha
- Department of Neurology; Medical University of South Carolina; Charleston South Carolina U.S.A
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