[Value of diagnostic imaging in evaluation of electroconvulsive therapy]

Magnetic resonance imaging (MRI), positron emission tomography (PET), and single photon emission computed tomography (SPECT) may be able to investigate the clinical efficacy and underlying neuronal processes of electroconvulsive therapy (ECT). The following review focuses on neuroimaging in ECT. Neuroimaging findings support that ECT does not result in significant macroscopic structural changes. However, in patients with subtle structural changes such as subcortical lesions and dilatation of lateral ventricles before ECT, the possibilities of poor therapeutic outcome, increased incidence of delirium, and longer-lasting cognitive deficits should be considered. Functional studies show reduced blood flow and glucose metabolism during the first days after ECT. Afterwards, their normalization can be observed, which seems to correlate to clinical improvement. The importance of this suppression effect needs to be further elucidated. Future studies of receptor systems and longitudinal studies will open new perspectives in future imaging research.