Brain Topography

, Volume 27, Issue 1, pp 197–207 | Cite as

The Value of Magnetoencephalography to Guide Electrode Implantation in Epilepsy

  • Zaloa Agirre-Arrizubieta
  • Ngoc J. Thai
  • Antonio Valentín
  • Paul L. Furlong
  • Stefano Seri
  • Richard P. Selway
  • Robert D. C. Elwes
  • Gonzalo Alarcón
Original Paper


To investigate if Magnetoencephalography (MEG) can add non-redundant information to guide implantation sites for intracranial recordings (IR). The contribution of MEG to intracranial recording planning was evaluated in 12 consecutive patients assessed pre-surgically with MEG followed by IR. Primary outcome measures were the identification of focal seizure onset in IR and favorable surgical outcome. Outcome measures were compared to those of 12 patients matched for implantation type in whom non-invasive pre-surgical assessment suggested clear hypotheses for implantation (non-MEG group). In the MEG group, non-invasive assessment without MEG was inconclusive, and MEG was then used to further help identify implantation sites. In all MEG patients, at least one virtual MEG electrode generated suitable hypotheses for the location of implantations. No differences in outcome measures were found between non-MEG and MEG groups. Although the MEG group included more complex patients, it showed similar percentage of successful implantations as the non-MEG group. This suggests that MEG can contribute to identify implantation sites where standard methods failed.


Magnetoencephalography Beamformers Epilepsy surgery Invasive recording Epileptogenic zone Magnetic source imaging 



Aston MEG Centre is supported by funding from the Wellcome Trust and the Dr. Hadwen Trust for Humane Research. MRI’s used for MEG co-registration were funded by the Lord Dowding Fund for Humane Research.

Ethical Approval

This study has been approved by Aston University Research Committee (2007/42), South Birmingham Local Research Committee, and King’s College Hospital Neuroscience Audit Committee.


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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  • Zaloa Agirre-Arrizubieta
    • 1
    • 2
  • Ngoc J. Thai
    • 3
  • Antonio Valentín
    • 1
    • 4
  • Paul L. Furlong
    • 3
  • Stefano Seri
    • 3
  • Richard P. Selway
    • 5
  • Robert D. C. Elwes
    • 1
    • 6
  • Gonzalo Alarcón
    • 1
    • 4
    • 7
  1. 1.Department of Clinical NeurophysiologyKing’s College HospitalLondonUK
  2. 2.Department of Clinical NeurophysiologyKent and Canterbury HospitalKentUK
  3. 3.Wellcome Trust Laboratory for MEG Studies, Aston Brain Centre, School of Life and Health SciencesAston UniversityBirminghamUK
  4. 4.Department of Clinical Neuroscience, Institute of PsychiatryKing’s College HospitalLondonUK
  5. 5.Department of NeurosurgeryKing’s College HospitalLondonUK
  6. 6.Department of NeurologyKing’s College HospitalLondonUK
  7. 7.Departamento de FisiologíaUniversidad ComplutenseMadridSpain

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