Modelling the temporal region in patients with temporal lobe epilepsy.
EEG interictal epileptiform discharges in temporal lobe epilepsy are associated with magnetic fields. The maxima of magnetic spikes recorded over the spherical portions of the head appear fairly symmetric, whereas those over the lower temporal region often have irregular shapes. Furthermore, their magnitude is often unequal with the extremum over the lower temporal region usually of lower magnitude than the extremum over the upper temporal region. This lack of symmetry in shape and magnitude may be due to non-sphericity of the skull over the temporal region or to variations in conductivities of intervening tissues. We present our observation in two patients suggesting that the surface contours of the head contribute to the apparent asymmetries of the field pattern but that the head contours alone may not account for the asymmetries seen in the clinical data.
D003198:Computer Simulation; D004569:Electroencephalography / Q000379:methods; D004833:Epilepsy, Temporal Lobe / Q000503:physiopathology*; D006801:Humans; D008959:Models, Neurological; D013702:Temporal Lobe / Q000033:anatomy & histology* / Q000503:physiopathology