Feasibility and limitations of magnetoencephalographic detection of epileptic discharges: Simultaneous recording of magnetic fields and electrocorticography

H. Shigeto, T. Morioka, K. Hisada, S. Nishio, H. Ishibashi, D. I. Kira, S. Tobimatsu, M. Kato

Research output: Contribution to journalArticle

55 Citations (Scopus)

Abstract

Magnetoencephalography (MEG) is considered clinically useful in localizing the epileptogenic focus in partial epilepsy. However, the relationship between the extent of the brain involved in paroxysmal activities and the magnetic field changes at the scalp has not been fully clarified. Furthermore, whether paroxysmal activities generated in deep brain structures such as the hippocampus can be detected magnetically is uncertain. Eight patients with temporal lobe epilepsy and two with extratemporal lobe epilepsy underwent chronic recording from subdural electrodes. Magnetic and electrocorticographic discharges representing epileptic activity were recorded simultaneously. MEG recorded magnetic field changes originating from paroxysmal activity in the superiolateral cerebral cortex when the amplitudes of the electrical paroxysmal activities exceeded 100 μV and extended over more than 3 cm2 of cortical surface. MEG failed to record paroxysmal activity localized to the medial temporal lobe. MEG is often useful in identifying a spike focus in the superiolateral aspects of the cerebral hemisphere, but not discharges arising from the medial temporal lobe. Rapid decay of the magnetic field is likely to be the reason for this limited sensitivity to medial discharges.

Original languageEnglish
Pages (from-to)531-536
Number of pages6
JournalNeurological Research
Volume24
Issue number6
DOIs
Publication statusPublished - Sep 1 2002

Fingerprint

Magnetoencephalography
Magnetic Fields
Temporal Lobe
Partial Epilepsy
Temporal Lobe Epilepsy
Brain
Cerebrum
Scalp
Cerebral Cortex
Epilepsy
Hippocampus
Electrodes
Electrocorticography

All Science Journal Classification (ASJC) codes

  • Neurology
  • Clinical Neurology

Cite this

Feasibility and limitations of magnetoencephalographic detection of epileptic discharges : Simultaneous recording of magnetic fields and electrocorticography. / Shigeto, H.; Morioka, T.; Hisada, K.; Nishio, S.; Ishibashi, H.; Kira, D. I.; Tobimatsu, S.; Kato, M.

In: Neurological Research, Vol. 24, No. 6, 01.09.2002, p. 531-536.

Research output: Contribution to journalArticle

@article{e0e91b50642e45c8a5e5c11caaabc4c4,
title = "Feasibility and limitations of magnetoencephalographic detection of epileptic discharges: Simultaneous recording of magnetic fields and electrocorticography",
abstract = "Magnetoencephalography (MEG) is considered clinically useful in localizing the epileptogenic focus in partial epilepsy. However, the relationship between the extent of the brain involved in paroxysmal activities and the magnetic field changes at the scalp has not been fully clarified. Furthermore, whether paroxysmal activities generated in deep brain structures such as the hippocampus can be detected magnetically is uncertain. Eight patients with temporal lobe epilepsy and two with extratemporal lobe epilepsy underwent chronic recording from subdural electrodes. Magnetic and electrocorticographic discharges representing epileptic activity were recorded simultaneously. MEG recorded magnetic field changes originating from paroxysmal activity in the superiolateral cerebral cortex when the amplitudes of the electrical paroxysmal activities exceeded 100 μV and extended over more than 3 cm2 of cortical surface. MEG failed to record paroxysmal activity localized to the medial temporal lobe. MEG is often useful in identifying a spike focus in the superiolateral aspects of the cerebral hemisphere, but not discharges arising from the medial temporal lobe. Rapid decay of the magnetic field is likely to be the reason for this limited sensitivity to medial discharges.",
author = "H. Shigeto and T. Morioka and K. Hisada and S. Nishio and H. Ishibashi and Kira, {D. I.} and S. Tobimatsu and M. Kato",
year = "2002",
month = "9",
day = "1",
doi = "10.1179/016164102101200492",
language = "English",
volume = "24",
pages = "531--536",
journal = "Neurological Research",
issn = "0161-6412",
publisher = "Maney Publishing",
number = "6",

}

TY - JOUR

T1 - Feasibility and limitations of magnetoencephalographic detection of epileptic discharges

T2 - Simultaneous recording of magnetic fields and electrocorticography

AU - Shigeto, H.

AU - Morioka, T.

AU - Hisada, K.

AU - Nishio, S.

AU - Ishibashi, H.

AU - Kira, D. I.

AU - Tobimatsu, S.

AU - Kato, M.

PY - 2002/9/1

Y1 - 2002/9/1

N2 - Magnetoencephalography (MEG) is considered clinically useful in localizing the epileptogenic focus in partial epilepsy. However, the relationship between the extent of the brain involved in paroxysmal activities and the magnetic field changes at the scalp has not been fully clarified. Furthermore, whether paroxysmal activities generated in deep brain structures such as the hippocampus can be detected magnetically is uncertain. Eight patients with temporal lobe epilepsy and two with extratemporal lobe epilepsy underwent chronic recording from subdural electrodes. Magnetic and electrocorticographic discharges representing epileptic activity were recorded simultaneously. MEG recorded magnetic field changes originating from paroxysmal activity in the superiolateral cerebral cortex when the amplitudes of the electrical paroxysmal activities exceeded 100 μV and extended over more than 3 cm2 of cortical surface. MEG failed to record paroxysmal activity localized to the medial temporal lobe. MEG is often useful in identifying a spike focus in the superiolateral aspects of the cerebral hemisphere, but not discharges arising from the medial temporal lobe. Rapid decay of the magnetic field is likely to be the reason for this limited sensitivity to medial discharges.

AB - Magnetoencephalography (MEG) is considered clinically useful in localizing the epileptogenic focus in partial epilepsy. However, the relationship between the extent of the brain involved in paroxysmal activities and the magnetic field changes at the scalp has not been fully clarified. Furthermore, whether paroxysmal activities generated in deep brain structures such as the hippocampus can be detected magnetically is uncertain. Eight patients with temporal lobe epilepsy and two with extratemporal lobe epilepsy underwent chronic recording from subdural electrodes. Magnetic and electrocorticographic discharges representing epileptic activity were recorded simultaneously. MEG recorded magnetic field changes originating from paroxysmal activity in the superiolateral cerebral cortex when the amplitudes of the electrical paroxysmal activities exceeded 100 μV and extended over more than 3 cm2 of cortical surface. MEG failed to record paroxysmal activity localized to the medial temporal lobe. MEG is often useful in identifying a spike focus in the superiolateral aspects of the cerebral hemisphere, but not discharges arising from the medial temporal lobe. Rapid decay of the magnetic field is likely to be the reason for this limited sensitivity to medial discharges.

UR - http://www.scopus.com/inward/record.url?scp=0036719105&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0036719105&partnerID=8YFLogxK

U2 - 10.1179/016164102101200492

DO - 10.1179/016164102101200492

M3 - Article

C2 - 12238617

AN - SCOPUS:0036719105

VL - 24

SP - 531

EP - 536

JO - Neurological Research

JF - Neurological Research

SN - 0161-6412

IS - 6

ER -