[Electroencephalographic study of 40 patients with subacute sclerosing panencephalitis].

Among viral diseases, subacute sclerosing panencephalitis is one of the most frequent in Iran (more than 300 cases in two neurological centers and for the last ten years). This paper is devoted to an electroencephalographic study of 40 patients: visual analysis of EEG rhythms (frequency, amplitude, lability, morphology), effects of activation methods, description of pathological EEG patterns (periodic paroxysmal complexes in 38 cases; slow or fast spikes, polyspikes and bifrontal or diffuse spikewaves in 9 cases; localized comitial abnormal patterns in 5 cases; bifrontal delta rhythm in 13 cases). From this description, we suggest an hypothesis of a diffuse localisation at the origin of periodic paroxysmal patterns: the periodic discharge of immune complexes from cerebral tissue into the cerebral circulation would constitute a synchronizing system which periodically modifies the blood-brain barrier permeability.