Non-Invasive EEG Source Localization Using Particle Swarm Optimization: A Clinical Experiment

Y. Shirvany, F. Edelvik, S. Jakobsson, A. Hedström, Q. Mahmood, A. Chodorowski, M. Persson, Proc. from 34th International Conference of the IEEE Engineering in Medicine & Biology Society, August 2012.

Abstract

One of the most important steps of pre-surgical diagnosis in patients with medically intractable epilepsy is to find the precise location of the epileptogenic foci. An Electroencephalography (EEG) is a non-invasive standard tool used at epilepsy surgery center for pre-surgical diagnosis. In this paper a modified particle swarm optimization (MPSO) method is applied to a real EEG data, i.e., a somatosensory evoked potentials (SEPs) measured from a healthy subject, to solve the EEG source localization problem. A high resolution 1 mm hexahedra finite element volume conductor model of the subject’s head was generated using T1-weighted magnetic resonance imaging data. An exhaustive search pattern and the MPSO method were then applied to the peak of the averaged SEPs data. The non-invasive EEG source analysis methods localized the somatosensory cortex area where our clinical expert expected the received SEPs. The proposed inverse problem solver found the global minima with acceptable accuracy and reasonable number of iterations.

 

Authors and Affiliations

  • Y. Shirvany, Dep. of Signals and Systems, Chalmers University of Technology and MedTechWest Center
  • F. Edelvik, Fraunhofer-Chalmers Centre
  • S. Jakobsson, Fraunhofer-Chalmers Centre
  • A. Hedström, The Sahlgrenska Academy
  • Q. Mahmood, Dep. of Signals and Systems, Chalmers University of Technology and MedTechWest Center
  • A. Chodorowski, Dep. of Signals and Systems, Chalmers University of Technology and MedTechWest Center
  • M. Persson, Dep. of Signals and Systems, Chalmers University of Technology and MedTechWest Center



Photo credits: Nic McPhee