Objective: Characterization of the ictal electroencephalogram (EEG) generated during ultrabrief pulse electroconvulsive therapy (ECT) is important to progress its use in routine ECT practice particularly in indicating treatment efficacy. The study compared 2- to 5-Hz and 5.2- to 13-Hz bands of the ictal EEG signal between brief- and ultrabrief-pulse ECT.
Methods: Twenty-five patients with major depression were randomized to brief- (1 millisecond [ms]) and ultrabrief-pulse (0.3 ms) right unilateral ECT. In sessions 2 to 8, when patients in either group received 6 times threshold ECT, right and left frontal ictal EEG between ultrabrief (n = 60) and brief pulse (n = 63) were compared. Electroencephalographic spectra from 2- to 5-Hz and 5.2- to 13-Hz bands in the mid and postictal phases were subjected to multitaper jackknife analysis of spectral power density (μV2/Hz) and its SD or “regularity” (μV2/Hz), peak spectral frequency (Hz), and its standard deviation (SD) or regularity (Hz). Linear mixed-effect models were used to compare the outcomes.
Results: In ultrabrief ECT, spectral power density and its SD were significantly smaller within the mid seizure of both bands, whereas peak frequency and its SD were similar. Postseizure suppression of spectral power density of both bands was similar in either treatments.
Conclusion: Lower spectral power densities were noted with ultrabrief-pulse ECT vis-a-vis brief-pulse ECT. However, in ultrabrief pulse ECT, regularity measures and postseizure suppression were comparable to brief-pulse ECT.