MRI T 2 relaxometry of brain regions and cognitive dysfunction following electroconvulsive therapy

Background: Although electroconvulsive therapy (ECT) causes no structural brain damage, recent studies reported altered brain perfusion acutely following ECT. This is in keeping with brain edema which was noted in animal experiments following electroconvulsive shock. Aim: This study examined alteration in magnetic resonance imaging (MRI) T 2 relaxation time, a measure of brain edema, and its relation to therapeutic efficacy, orientation and memory impairment with ECT. Materials and Methods: Fifteen drug-naive consenting patients of major depressive disorder with melancholia (DSM-IV) received ECT as first-line treatment. MRI scans were done before the first ECT and at 2 hours after the second ECT. T 2 relaxation time was measured bilaterally in thalamus, hippocampus, medial temporal lobes and dorsolateral frontal cortex by a blind rater. Results: Depression scores and memory scores were reduced significantly both after the second and fifth ECT. There was no change in T 2 relaxation time after second ECT. Conclusion: The finding suggests that ECT does not produce demonstrable change acutely in brain parenchyma detectable by MRI scans.