Magnetoencephalography for Epilepsy Presurgical Evaluation

Geller, Aaron S.; Teale, Peter; Kronberg, Eugene; Ebersole, John S.

doi:10.1007/s11910-023-01328-5

Cited by 3 publications

(2 citation statements)

References 117 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Electromagnetic source imaging (ESI/MSI) is currently not considered as standard in presurgical evaluation [25]. Nevertheless, it has been recognized as a useful tool especially when phase 1a investigations are inconclusive [73][74][75]. Clinical position paper and on ESI and a Clinical Practice Guideline for recording and analysis of spontaneous cerebral activity are available from the American Clinical Magnetoencephalography Society [76,77].…”

Section: Current Practices Of Electromagnetic Source Localization Wit...mentioning

confidence: 99%

Evidence based noninvasive presurgical evaluation for patients with drug resistant epilepsies

Trinka,

Koepp,

Kalss

et al. 2024

Current Opinion in Neurology

View full text Add to dashboard Cite

Purpose of review To review the current practices and evidence for the diagnostic accuracy and the benefits of presurgical evaluation. Recent findings Preoperative evaluation of patients with drug-resistant focal epilepsies and subsequent epilepsy surgery leads to a significant proportion of seizure-free patients. Even those who are not completely seizure free postoperatively often experience improved quality of life with better social integration. Systematic reviews and meta-analysis on the diagnostic accuracy are available for Video-electroencephalographic (EEG) monitoring, magnetic resonance imaging (MRI), electric and magnetic source imaging, and functional MRI for lateralization of language and memory. There are currently no evidence-based international guidelines for presurgical evaluation and epilepsy surgery. Summary Presurgical evaluation is a complex multidisciplinary and multiprofessional clinical pathway. We rely on limited consensus-based recommendations regarding the required staffing or methodological expertise in epilepsy centers.

show abstract

Section: Current Practices Of Electromagnetic Source Localization Wit...mentioning

confidence: 99%

Evidence based noninvasive presurgical evaluation for patients with drug resistant epilepsies

Trinka,

Koepp,

Kalss

et al. 2024

Current Opinion in Neurology

View full text Add to dashboard Cite

show abstract

“…Magnetoencephalography (MEG) is a neuroimaging technique with a high spatiotemporal resolution [1], which has been applied in the localization of epilepsy and early diagnosis research on psychiatric diseases [2,3]. With the development of optically pumped magnetometers (OPMs) in recent years, wearable OPM-MEG systems [4,5] have not only overcome the disadvantages of traditional MEG devices [6] that need to operate at low temperatures and sensors that are fixed and far away from the subject's body but have also acquired an improved level of signal sensitivity [7].…”

Section: Introductionmentioning

confidence: 99%

Automatic Estimation of the Interference Subspace Dimension Threshold in the Subspace Projection Algorithms of Magnetoencephalography Based on Evoked State Data

Zhao,

Wang,

Gao

et al. 2024

Bioengineering

View full text Add to dashboard Cite

A class of algorithms based on subspace projection is widely used in the denoising of magnetoencephalography (MEG) signals. Setting the dimension of the interference (external) subspace matrix of these algorithms is the key to balancing the denoising effect and the degree of signal distortion. However, most current methods for estimating the dimension threshold rely on experience, such as observing the signal waveforms and spectrum, which may render the results too subjective and lacking in quantitative accuracy. Therefore, this study proposes a method to automatically estimate a suitable threshold. Time–frequency transformations are performed on the evoked state data to obtain the neural signal of interest and the noise signal in a specific time–frequency band, which are then used to construct the objective function describing the degree of noise suppression and signal distortion. The optimal value of the threshold in the selected range is obtained using the weighted-sum method. Our method was tested on two classical subspace projection algorithms using simulation and two sensory stimulation experiments. The thresholds estimated by the proposed method enabled the algorithms to achieve the best waveform recovery and source location error. Therefore, the threshold selected in this method enables subspace projection algorithms to achieve the best balance between noise removal and neural signal preservation in subsequent MEG analyses.

show abstract

MEG in MRI-Negative Patients with Focal Epilepsy

Kreidenhuber,

Poppert,

Mauritz

et al. 2024

JCM

View full text Add to dashboard Cite

Objectives: To review the evidence on the clinical value of magnetic source imaging (MSI) in patients with refractory focal epilepsy without evidence for an epileptogenic lesion on magnetic resonance imaging (“MRI-negative” or “non-lesional MRI”). Methods: We conducted a systematic literature search on PUBMED, which was extended by researchrabbit.ai using predefined criteria to identify studies that applied MSI in MRI-negative patients with epilepsy. We extracted data on patient characteristics, MSI methods, localization results, surgical outcomes, and correlation with other modalities. Results: We included 23 studies with a total of 512 non-lesional epilepsy patients who underwent MSI. Most studies used equivalent current dipole (ECD) models to estimate the sources of interictal epileptic discharges (IEDs). MEG detected IEDs in 32–100% of patients. MSI results were concordant with other modalities, such as EEG, PET, and SPECT, in 3892% of cases. If MSI concordant surgery was performed, 52–89% of patients achieved seizure freedom. MSI contributed to the decision-making process in 28–75% of cases and altered the surgical plan in 5–33% of cases. Conclusions: MSI is a valuable diagnostic tool for MRI-negative patients with epilepsy, as it can detect and localize IEDs with high accuracy and sensitivity, and provides useful information for surgical planning and predicts outcomes. MSI can also complement and refine the results of other modalities, such as EEG and PET, and optimize the use of invasive recordings. MSI should be considered as part of the presurgical evaluation, especially in patients with non-lesional refractory epilepsy.

show abstract

Magnetoencephalography for Epilepsy Presurgical Evaluation

Cited by 3 publications

References 117 publications

Evidence based noninvasive presurgical evaluation for patients with drug resistant epilepsies

Evidence based noninvasive presurgical evaluation for patients with drug resistant epilepsies

Automatic Estimation of the Interference Subspace Dimension Threshold in the Subspace Projection Algorithms of Magnetoencephalography Based on Evoked State Data

MEG in MRI-Negative Patients with Focal Epilepsy

Contact Info

Product

Resources

About