A systematic review and computational modelling analysis of unilateral montages in electroconvulsive therapy

Abstract

S, Loo CK. A systematic review and computational modelling analysis of unilateral montages in electroconvulsive therapy Objective: To examine the clinical outcomes of ECT unilateral placements compared in prior studies and apply insights from computational modelling to understand differences between placements. Methods: PubMed, Embase, Scopus and PsycINFO and reference lists were systematically searched for studies of depressed patients where two unilateral placements were compared and clinical outcomes were reported. Computational modelling was done to generate electric field maps for each unilateral placement identified in the systematic review. Results: A total of 29 studies met criteria for inclusion. Eight studies reported efficacy outcomes and 23 studies reported cognitive outcomes. Most studies found no significant difference in efficacy between right unilateral (RUL) and left unilateral (LUL) ECT, and no difference was found between temporo-parietal and fronto-temporal ECT. For the majority of studies, RUL placements had better verbal anterograde memory outcomes compared with the LUL placements. There was some evidence suggestive of cognitive advantages for fronto-frontal and fronto-parietal placements relative to temporo-parietal ECT. Conclusions: For efficacy, studies mainly focused on the comparison of right vs. left hemispheric stimulation, with the available evidence suggesting no substantive difference. RUL placements tended to have better verbal anterograde memory outcomes relative to LUL placements, though limited differences were found between the RUL placements.• RUL and LUL ECT were found to be comparable in efficacy in most studies.• RUL tended to have better verbal memory outcomes relative to LUL ECT placements. • Fronto-frontal and fronto-parietal placements may be superior to temporo-parietal placement in cognitive outcomes. Limitations• The included studies were small, and heterogeneous in methodology and the reporting of treatment methods and clinical outcomes.• Insufficient report of unilateral montage details in the included studies may have hindered the accuracy of interpreting the clinical outcomes and computational modelling. 408

Clinicians’ Approach to Cognitive Impairment After Electroconvulsive Therapy: Current Situations and Challenges

“…D. Martin et al demonstrated some evidence to reach the best cognitive profile in favor of frontalfrontal and frontal-parietal placement relative to the temporoparietal position. Furthermore, this study showed better verbal anterograde memory outcome in the right unilateral placement in comparison to the left unilateral placement (20).…”

“…Most of the literature suggests that cognitive state is usually affected by ECT (18)(19)(20). The results of this study showed that more than 80% of the experts believe that the cognitive assessment is necessary before and after ECT; nonetheless, only 15% of the specialists referred patients for cognitive evaluation.…”

Brief cognitive screening instruments for electroconvulsive therapy: Which one should I use?

“…Acute retrograde amnesia for information acquired immediately prior to the administration of a single ECT treatment is also common. These side effects have been observed across multiple different memory domains, are typically large in magnitude (Martin et al, 2019) and are sensitive to ECT treatment factors, including electrode montage (Prudic et al, 1994), dose (Sackeim et al, 1993) and pulse width (Loo et al, 2015;Sackeim et al, 2008). While acute cognitive side effects other than memory have also been investigated (e.g.…”