[Multiple EEG examinations in patients with refractory endogenous depression after unilateral ECT]

In 37 inpatients /27 females and 10 males, mean age--49.8 +/- +/- 10.3 years/, with the diagnosis of refractory endogenous depression, after completing a course of unilateral ECT /u-ECT/, multiple EEG examinations were performed during a year of observation. Routine EEG examinations were carried out after a washing out period of two weeks, using an 8 channel Medicor-Orion EEG device. The patients were examined before treatment and 2, 4 and 6 weeks and then 3, 6 and 12 months after the course of ECT. The mean number of ECT which the patients received during a therapeutic session was 8.4 +/- +/- 2.8. Two weeks after completing the course of U-ECT, pathologic tracings in the EEG were found in 17 patients--mainly slowing of the basic alpha activity and slow theta waves. A month after the course of U-ECT in the majority of patients--32 there was a normal EEG tracing. After 6 weeks changes in EEG were found in 2 patients. In one of them they were still present after completion of U-ECT. No significant relationship between the persistence of EEG changes and the number of U-ECT received during the last therapeutic session or the quantity of ECT treatments in the past was detected. The result of this work may support the hypothesis that changes in the biological activity of the brain after ECT therapy are reversible in nature and most probably are a reflection of functional changes in the neurons, partly connected with the therapeutic process or without any relationship with that occurring from a wide spectrum of neurochemical activity of the method of treatment.