Simultaneous pattern of rCBF and rCMRGlu in continuation ECT: case reports

This report presents the simultaneous pattern of cerebral blood flow and cerebral glucose metabolism in two patients with a major depressive disorder who were undergoing continuation ECT. The regional cerebral blood flow and regional cerebral metabolic rate of these patients were imaged using double isotope 18F-FDG and 99mTc-HMPAO single-photon emission computed tomography before acute ECT and after the completion of continuation ECT; bilateral electrode placement (11 and 12 sessions, respectively) was chosen for the acute treatment course whereas unilateral placement was the method chosen during the continuation phase (6 and 7 sessions, respectively). Baseline SPECT scans of our patients, who continued to receive treatment with medication, were normal as compared with controls; however, scans at the end of continuation ECT revealed decreased uptake activities of both isotopes in prefrontal regions on both sides, which might be associated with the therapeutic impact and efficacy. These results are consistent with previous brain imaging studies of acute ECT. Furthermore, marked changes in both basal ganglia regions were found. The pattern of the isotope uptake ratios did not show any similarities to neurodegenerative processes, which might confirm the high safety profile of ECT also during the continuation phase of treatment.