摘要：Long-term electroencephalographic (EEG) recordings are important in the presurgical evaluation
of refractory partial epilepsy for the delineation of the ictal onset zones. In this paper, we introduce
a new concept for an automatic, fast, and objective localisation of the ictal onset zone in ictal EEG
recordings. Canonical decomposition of ictal EEG decomposes the EEG in atoms. One or more atoms
are related to the seizure activity. A single dipole was then fitted to model the potential distribution of
each epileptic atom. In this study, we performed a simulation study in order to estimate the dipole
localisation error. Ictal dipole localisation was very accurate, even at low signal-to-noise ratios, was not
affected by seizure activity frequency or frequency changes, and was minimally affected by the waveform
and depth of the ictal onset zone location. Ictal dipole localisation error using 21 electrodes was around
10.0 mm and
improved more than tenfold in the range of 0.5–1.0 mm using 148 channels. In conclusion, our
simulation study of canonical decomposition of ictal scalp EEG allowed a robust and accurate
localisation of the ictal onset zone.
