Read by QxMD icon Read

Epilepsy surgery, MEG

Daeyoung Kim, Eun Yeon Joo, Dae-Won Seo, Min-Young Kim, Yong-Ho Lee, Hyuk Chan Kwon, Jae-Moon Kim, Seung Bong Hong
BACKGROUND: We conducted the study to examine accuracy of the magnetoencephalography (MEG) spike source localization in presurgical evaluation of patients with medically refractory focal epilepsy. METHODS: Ten consecutive patients with refractory focal epilepsy who were candidates for two-stage surgery with long-term intracranial electroencephalography (ICEEG) monitoring were enrolled. Interictal MEG recordings with simultaneous scalp EEG were obtained within 7days before the ICEEG electrode implantation...
August 16, 2016: Epilepsy Research
Elizabeth W Pang, O C Snead Iii
New advances in structural neuroimaging have revealed the intricate and extensive connections within the brain, data which have informed a number of ambitious projects such as the mapping of the human connectome. Elucidation of the structural connections of the brain, at both the macro and micro levels, promises new perspectives on brain structure and function that could translate into improved outcomes in functional neurosurgery. The understanding of neuronal structural connectivity afforded by these data now offers a vista on the brain, in both healthy and diseased states, that could not be seen with traditional neuroimaging...
2016: Frontiers in Neuroanatomy
Björn Sommer, Karl Roessler, Stefan Rampp, Hajo M Hamer, Ingmar Blumcke, Hermann Stefan, Michael Buchfelder
BACKGROUND: Especially in hidden lesions causing drug-resistant frontal lobe epilepsy (FLE), the localization of the epileptic zone EZ can be a challenge. Magnetoencephalography (MEG) can raise the chances for localization of the (EZ) in combination with electroencephalography (EEG). We investigated the impact of MEG-guided epilepsy surgery with the aid of neuronavigation and intraoperative MR imaging (iopMRI) on seizure outcome of FLE patients. METHODS: Twenty-eight patients (15 females, 13 males; mean age 31...
October 2016: Epilepsy Research
Philip Lee, Ahmad Alhourani, Robert Mark Richardson
INTRODUCTION: Changes in connectivity have been found surrounding epileptic foci during resting state magnetoencephalography (MEG). One manifestation of these changes is disorganization manifested by increased interconnectivity within a region. This abnormal interconnectivity indicates a decrease in efficiency, because efficient function within a system requires communication across brain regions. Surgical resection of seizure foci may attenuate these aberrant patterns of connectivity...
August 2016: Neurosurgery
Dario J Englot, John David Rolston, Doris D Wang, Heidi E Kirsch, Srikantan S Nagarajan, Edward F Chang
INTRODUCTION: Potential uses of magnetoencephalography (MEG) to help noninvasively identify the epileptogenic zone (EZ) in epilepsy surgery and predict seizure outcome include: (1) epileptic spike localization, (2) slow-wave lateralization, and (3) measurements of resting-state functional connectivity. This is the first study to evaluate multimodal MEG techniques to aid the presurgical evaluation of patients with intractable focal epilepsy. METHODS: We studied 132 focal epilepsy patients who received MEG followed by resection at our institution (follow-up mean = 3...
August 2016: Neurosurgery
Ida A Nissen, Nicole E C van Klink, Maeike Zijlmans, Cornelis J Stam, Arjan Hillebrand
OBJECTIVE: Previous studies have associated network hubs and epileptiform activity, such as spikes and high frequency oscillations (HFOs), with the epileptogenic zone. The epileptogenic zone is approximated by the area that generates interictal epileptiform activity: the irritative zone. Our aim was to determine the relation between network hubs and the irritative zone. METHODS: Interictal resting-state MEG recordings of 12 patients with refractory epilepsy were analysed...
July 2016: Clinical Neurophysiology: Official Journal of the International Federation of Clinical Neurophysiology
Midori Nakajima, Elysa Widjaja, Shiro Baba, Yosuke Sato, Ryuhei Yoshida, Maya Tabei, Ayaka Okazaki, Satoru Sakuma, Stephanie A Holowka, Ayako Ochi, O Carter Snead, James T Rutka, James M Drake, Hideaki Shiraishi, Sam Doesburg, Hiroshi Otsubo
OBJECTIVE: To investigate whether the magnetoencephalography (MEG) single moving dipole (SMD) method could delineate the epileptic zone of focal cortical dysplasia (FCD) at the bottom of sulcus (FCDB). METHODS: We retrospectively analyzed 17 children (11 male; mean age 8.8 years, range 3-17 years) with FCD type II who underwent epilepsy surgery. We compared spatial congruence between the following: (1) MEG cluster and FCDB and (2) MEG cluster and FCD at the brain surface (FCDS)...
July 2016: Epilepsia
I A Nissen, C J Stam, J Citroen, J C Reijneveld, A Hillebrand
OBJECTIVE: Identifying epilepsy patients for whom clinical MEG is likely to be beneficial avoids or optimizes burdensome ancillary investigations. We determined whether it could be predicted upfront if MEG would be able to generate a hypothesis about the location of the epileptogenic zone (EZ), and in which patients MEG fails to do so. METHODS: MEG recordings of 382 epilepsy patients with inconclusive findings regarding EZ localization prior to MEG were acquired for preoperative evaluation...
August 2016: Epilepsy Research
Younes Zerouali, Philippe Pouliot, Manon Robert, Ismail Mohamed, Alain Bouthillier, Frédéric Lesage, Dang K Nguyen
Failure to recognize insular cortex seizures has recently been identified as a cause of epilepsy surgeries targeting the temporal, parietal, or frontal lobe. Such failures are partly due to the fact that current noninvasive localization techniques fare poorly in recognizing insular epileptic foci. Our group recently demonstrated that magnetoencephalography (MEG) is sensitive to epileptiform spikes generated by the insula. In this study, we assessed the potential of distributed source imaging and functional connectivity analyses to distinguish insular networks underlying the generation of spikes...
September 2016: Human Brain Mapping
Brian E Mouthaan, Matea Rados, Péter Barsi, Paul Boon, David W Carmichael, Evelien Carrette, Dana Craiu, J Helen Cross, Beate Diehl, Petia Dimova, Daniel Fabo, Stefano Francione, Vladislav Gaskin, Antonio Gil-Nagel, Elena Grigoreva, Alla Guekht, Edouard Hirsch, Hrvoje Hecimovic, Christoph Helmstaedter, Julien Jung, Reetta Kalviainen, Anna Kelemen, Vasilios Kimiskidis, Teia Kobulashvili, Pavel Krsek, Giorgi Kuchukhidze, Pål G Larsson, Markus Leitinger, Morten I Lossius, Roman Luzin, Kristina Malmgren, Ruta Mameniskiene, Petr Marusic, Baris Metin, Cigdem Özkara, Hrvoje Pecina, Carlos M Quesada, Fergus Rugg-Gunn, Bertil Rydenhag, Philippe Ryvlin, Julia Scholly, Margitta Seeck, Anke M Staack, Bernhard J Steinhoff, Valentin Stepanov, Oana Tarta-Arsene, Eugen Trinka, Mustafa Uzan, Viola L Vogt, Sjoerd B Vos, Serge Vulliémoz, Geertjan Huiskamp, Frans S S Leijten, Pieter Van Eijsden, Kees P J Braun
OBJECTIVE: In 2014 the European Union-funded E-PILEPSY project was launched to improve awareness of, and accessibility to, epilepsy surgery across Europe. We aimed to investigate the current use of neuroimaging, electromagnetic source localization, and imaging postprocessing procedures in participating centers. METHODS: A survey on the clinical use of imaging, electromagnetic source localization, and postprocessing methods in epilepsy surgery candidates was distributed among the 25 centers of the consortium...
May 2016: Epilepsia
Carolina Migliorelli, Joan F Alonso, Sergio Romero, Miguel A Mañanas, Rafał Nowak, Antonio Russi
OBJECTIVE: Medical intractable epilepsy is a common condition that affects 40% of epileptic patients that generally have to undergo resective surgery. Magnetoencephalography (MEG) has been increasingly used to identify the epileptogenic foci through equivalent current dipole (ECD) modeling, one of the most accepted methods to obtain an accurate localization of interictal epileptiform discharges (IEDs). Modeling requires that MEG signals are adequately preprocessed to reduce interferences, a task that has been greatly improved by the use of blind source separation (BSS) methods...
April 2016: Journal of Neural Engineering
Haitao Zhu, Jinlong Zhu, Forrest Sheng Bao, Hongyi Liu, Xuchuang Zhu, Ting Wu, Lu Yang, Yuanjie Zou, Rui Zhang, Gang Zheng
PURPOSE: Frontal lobe epilepsy is a common epileptic disorder and is characterized by recurring seizures that arise in the frontal lobes. The purpose of this study is to identify the epileptogenic regions and other abnormal regions in patients with left frontal lobe epilepsy (LFLE) based on the magnetoencephalogram (MEG), and to understand the effects of clinical variables on brain activities in patients with LFLE. METHOD: Fifteen patients with LFLE (23.20 ± 8...
January 2016: Seizure: the Journal of the British Epilepsy Association
Ronald B Willemse, Arjan Hillebrand, Hanneke E Ronner, W Peter Vandertop, Cornelis J Stam
OBJECTIVES: The presence of intracranial lesions or epilepsy may lead to functional reorganization and hemispheric lateralization. We applied a clinical magnetoencephalography (MEG) protocol for the localization of the contralateral and ipsilateral S1 and M1 of the foot and hand in patients with non-lesional epilepsy, stroke, developmental brain injury, traumatic brain injury and brain tumors. We investigated whether differences in activation patterns could be related to underlying pathology...
2016: NeuroImage: Clinical
Mona Pirmoradi, Boutheina Jemel, Anne Gallagher, Julie Tremblay, Fabien D'Hondt, Dang Khoa Nguyen, Renée Béland, Maryse Lassonde
OBJECTIVE: The aim of this study was to develop a presurgical magnetoencephalography (MEG) protocol to localize and lateralize expressive and receptive language function as well as verbal memory in patients with epilepsy. Two simple language tasks and a different analytical procedure were developed. METHODS: Ten healthy participants and 13 epileptic patients completed two language tasks during MEG recording: a verbal memory task and a verbal fluency task. As a first step, principal component analyses (PCA) were performed on source data from the group of healthy participants to identify spatiotemporal factors that were relevant to these paradigms...
January 2016: Epilepsy Research
Khalid Hamandi, Bethany C Routley, Loes Koelewijn, Krish D Singh
BACKGROUND: Non-invasive in vivo neurophysiological recordings with EEG/MEG are key to the diagnosis, classification, and further understanding of epilepsy. Historically the emphasis of these recordings has been the localisation of the putative sources of epileptic discharges. More recent developments see new techniques studying oscillatory dynamics, connectivity and network properties. NEW METHOD: New analysis strategies for whole head MEG include the development of spatial filters or beamformers for source localisation, time-frequency analysis for cortical dynamics and graph theory applications for connectivity...
February 15, 2016: Journal of Neuroscience Methods
Jack Solomon, Shaun Boe, Timothy Bardouille
OBJECTIVES: In patients with epilepsy or space occupying tumors in cortical regions, surgical resection is often considered as the primary treatment. Pre-surgical neuroimaging can provide a detailed map of pathological and functional cortex, leading to safer surgery. Mapping can be achieved non-invasively using magnetoencephalography (MEG), and is concordant with invasive findings. However, the reliability of MEG mapping between sessions is not well established. The inter-session reliability is an important property in pre-surgical mapping to establish resection margins, but repeated scans are impracticable...
December 2015: Clinical Neurology and Neurosurgery
Dario J Englot, Robert C Knowlton, Edward F Chang, Heidi E Kirsch, Srikantan S Nagarajan
INTRODUCTION: Intractable focal epilepsy is a devastating disorder with profound effects on cognition and quality of life. Epilepsy surgery can lead to seizure freedom in patients with focal epilepsy; however, sometimes it fails owing to an incomplete delineation of the epileptogenic zone (EZ). Brain networks in epilepsy can be studied with resting-state functional connectivity (RSFC) analysis, yet previous investigations using functional MRI or electrocorticography have produced inconsistent results...
August 2015: Neurosurgery
Maria Pardos, Milena Korostenskaja, Jing Xiang, Hisako Fujiwara, Ki H Lee, Paul S Horn, Anna Byars, Jennifer Vannest, Yingying Wang, Nat Hemasilpin, Douglas F Rose
Objective evaluation of language function is critical for children with intractable epilepsy under consideration for epilepsy surgery. The purpose of this preliminary study was to evaluate word recognition in children with intractable epilepsy by using magnetoencephalography (MEG). Ten children with intractable epilepsy (M/F 6/4, mean ± SD 13.4 ± 2.2 years) were matched on age and sex to healthy controls. Common nouns were presented simultaneously from visual and auditory sensory inputs in "match" and "mismatch" conditions...
2015: Behavioural Neurology
Dario J Englot, Srikantan S Nagarajan, Brandon S Imber, Kunal P Raygor, Susanne M Honma, Danielle Mizuiri, Mary Mantle, Robert C Knowlton, Heidi E Kirsch, Edward F Chang
OBJECTIVE: The efficacy of epilepsy surgery depends critically upon successful localization of the epileptogenic zone. Magnetoencephalography (MEG) enables noninvasive detection of interictal spike activity in epilepsy, which can then be localized in three dimensions using magnetic source imaging (MSI) techniques. However, the clinical value of MEG in the presurgical epilepsy evaluation is not fully understood, as studies to date are limited by either a lack of long-term seizure outcomes or small sample size...
June 2015: Epilepsia
Herm J Lamberink, Kim Boshuisen, Peter C van Rijen, Peter H Gosselaar, Kees P J Braun
OBJECTIVE: Over the past decades, the number of epilepsy surgeries in children has increased and indications for surgery have broadened. We studied the changes in patient characteristics between 1990 and 2011 in a nationwide cohort and related these to seizure outcome and postoperative medication status. Second, we tried to identify predictors for seizure outcome after pediatric epilepsy surgery. METHODS: To study changes over time, we divided this retrospective cohort of 234 children into two consecutive time periods of 11 years, and statistically compared the epochs in terms of patient characteristics, surgical variables, complications, seizure outcome, and postoperative medication status...
May 2015: Epilepsia
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"