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Ictal EEG source imaging in presurgical evaluation : High agreement between analysis methods

Beniczky, Sándor; Rosenzweig, Ivana; Scherg, Michael; Jordanov, Todor; Lanfer, Benjamin; Lantz, Göran LU and Larsson, Pål Gunnar (2016) In Seizure 43. p.1-5
Abstract

Purpose To determine the agreement between five different methods of ictal EEG source imaging, and to assess their accuracy in presurgical evaluation of patients with focal epilepsy. It was hypothesized that high agreement between methods was associated with higher localization-accuracy. Methods EEGs were recorded with a 64-electrode array. Thirty-eight seizures from 22 patients were analyzed using five different methods phase mapping, dipole fitting, CLARA, cortical-CLARA and minimum norm. Localization accuracy was determined at sub-lobar level. Reference standard was the final decision of the multidisciplinary epilepsy surgery team, and, for the operated patients, outcome one year after surgery. Results Agreement between all methods... (More)

Purpose To determine the agreement between five different methods of ictal EEG source imaging, and to assess their accuracy in presurgical evaluation of patients with focal epilepsy. It was hypothesized that high agreement between methods was associated with higher localization-accuracy. Methods EEGs were recorded with a 64-electrode array. Thirty-eight seizures from 22 patients were analyzed using five different methods phase mapping, dipole fitting, CLARA, cortical-CLARA and minimum norm. Localization accuracy was determined at sub-lobar level. Reference standard was the final decision of the multidisciplinary epilepsy surgery team, and, for the operated patients, outcome one year after surgery. Results Agreement between all methods was obtained in 13 patients (59%) and between all but one methods in additional six patients (27%). There was a trend for minimum norm being less accurate than phase mapping, but none of the comparisons reached significance. Source imaging in cases with agreement between all methods was not more accurate than in the other cases. Ictal source imaging achieved an accuracy of 73% (for operated patients: 86%). Conclusion There was good agreement between different methods of ictal source imaging. However, good inter-method agreement did not necessarily imply accurate source localization, since all methods faced the limitations of the inverse solution.

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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
EEG, Epilepsy surgery, Inverse solution, Seizure, Source imaging
in
Seizure
volume
43
pages
5 pages
publisher
Elsevier
external identifiers
  • scopus:84994792189
  • wos:000391420200001
ISSN
1059-1311
DOI
10.1016/j.seizure.2016.09.017
language
English
LU publication?
yes
id
dc169e74-75db-4792-8952-e1dc0a75f35c
date added to LUP
2016-11-25 10:47:24
date last changed
2017-10-01 05:26:29
@article{dc169e74-75db-4792-8952-e1dc0a75f35c,
  abstract     = {<p>Purpose To determine the agreement between five different methods of ictal EEG source imaging, and to assess their accuracy in presurgical evaluation of patients with focal epilepsy. It was hypothesized that high agreement between methods was associated with higher localization-accuracy. Methods EEGs were recorded with a 64-electrode array. Thirty-eight seizures from 22 patients were analyzed using five different methods phase mapping, dipole fitting, CLARA, cortical-CLARA and minimum norm. Localization accuracy was determined at sub-lobar level. Reference standard was the final decision of the multidisciplinary epilepsy surgery team, and, for the operated patients, outcome one year after surgery. Results Agreement between all methods was obtained in 13 patients (59%) and between all but one methods in additional six patients (27%). There was a trend for minimum norm being less accurate than phase mapping, but none of the comparisons reached significance. Source imaging in cases with agreement between all methods was not more accurate than in the other cases. Ictal source imaging achieved an accuracy of 73% (for operated patients: 86%). Conclusion There was good agreement between different methods of ictal source imaging. However, good inter-method agreement did not necessarily imply accurate source localization, since all methods faced the limitations of the inverse solution.</p>},
  author       = {Beniczky, Sándor and Rosenzweig, Ivana and Scherg, Michael and Jordanov, Todor and Lanfer, Benjamin and Lantz, Göran and Larsson, Pål Gunnar},
  issn         = {1059-1311},
  keyword      = {EEG,Epilepsy surgery,Inverse solution,Seizure,Source imaging},
  language     = {eng},
  month        = {12},
  pages        = {1--5},
  publisher    = {Elsevier},
  series       = {Seizure},
  title        = {Ictal EEG source imaging in presurgical evaluation : High agreement between analysis methods},
  url          = {http://dx.doi.org/10.1016/j.seizure.2016.09.017},
  volume       = {43},
  year         = {2016},
}