. Author manuscript; available in PMC: 2019 Jul 12.

Published in final edited form as: J Geriatr Psychiatry Neurol. 2013 Dec 30;27(1):33–46. doi: 10.1177/0891988713516542

Table 2.

Positron Emission Tomography (PET) and Longitudinal Changes in ECT.

Author (Year)	n Diagnosis Mean Age (SD) Male/Female Ratio of Responders/Total Medication Status	Stimulus Delivery Stimulus Waveform Stimulus Intensity (When Reported) Number ECT Sessions (SD)	Time From ECT Series to Post-ECT Imaging Assessment HC Group: Yes/No	Image Analysis	Longitudinal Neuroimaging Results
[¹⁸F]-Fluorodeoxyglucose (FDG) to measure regional cerebral metabolic rate of glucose (rCMRGlu)
Yuuki et al²⁸ (2005)	4 MDD with and without psychotic features; 3 bipolar I & II 58 years (9) 4 males/3 females 7/7 responders Patients remained on antidepressant medications; lithium and valproate were discontinued	Bitemporal Brief pulse Half-age stimulus intensity 6–20 treatments (range)	33 days HC: yes	Voxel-wise analysis (whole brain)	ECT time 1 vs time 2: decreased rCMRGlu in the bilateral medial frontal cortices and increased rCMRGlu in the left occipital and parietal lobes ECT time 1 vs HC: Patients had decreased rCMRGlu in frontal regions and the left caudate; patients had increased rCMRGlu in left parietal and right paracentral gyrus ECT time 2 vs HC: Patients continued to have decreased rCMRGlu in frontal regions and the left caudate; patients also continued to have increased rCMRGlu in the left parietal cortex. Patients did have normalization of aberrant rCMRGlu in the right DLPFC and right paracentral gyrus.
McCormick et al²⁹ (2007)	10 MDD with psychotic features 40 years (10) 6 male/4 female Median split divided sample into ‘‘better and poor’’ responders Patients remained on medications	RUL (n = 5), bitemporal (n = 5) Brief pulse Seizure threshold, RUL 6 × threshold; bitemporal 2.5 × threshold 10 treatments (6)	14–21 days (range) HC: no	Voxel-wise analysis (whole brain) and region of interest	ECT time 1 vs time 2: in voxel-wise (whole brain) analysis, decreased rCMRGlu in the right frontal operculum and insula, and increased rCMRGlu in left hippocampus; metabolic changes in left hippocampus and left ventral anterior cingulate also correlated with change in HDRS. In the region of interest analysis, the ‘‘better’’ ECT responders had increased rCMRGlu in the left subgenual anterior cingulate and left hippocampus relative to the ‘‘poor’’ ECT responders.
Suwa et al³⁰ (2012)	13 MDD; 3 bipolar II 33 years (8) 13 male/5 female 12/16 responders Patients remained on medications	Bitemporal Brief pulse Half-age stimulus intensity 10 treatments	12 days HC: yes	Voxel-wise analysis (whole brain)	ECT time 1 vs time 2: decreased rCMRGlu in frontal, parietal, and inferior temporal regions; increased rCMRGlu in the medial temporal gyrus and pons ECT time 1 vs HC: patients had decreased rCMRGlu in the left superior frontal gyrus and increased rCMRGlu in the bilateral temporal gyri ECT time 2 vs HC: patients had decreased rCMRGlu in left temporal and parietal cortices and bilateral frontal gyri; patients had increased rCMRGlu in the middle temporal and occipital regions
Reininghaus et al³¹ (2013)	12 MDD 56 years (12) 7 male/5 female 3/12 responders Patients remained on medications	9 bitemporal, 3 RUL Brief pulse Dose adjusted for age 8 treatments (fixed)	1–7 days (range) HC: no	Region of interest with normalization to activity in the pons	ECT time 1 vs time 2: increased rCMRGlu in the left temporal lobe; correlations with symptom changes and cognitive changes were not significant
[¹¹C] FLB 457 measures extrastriatal D2 receptor binding
Saijo et al³² (2010)	7 MDD 43 years (11) 5 male/2 female 7/7 responders Patients were treated with SSRI’s	Bitemporal Brief pulse Dose adjusted for age 6–7 treatments (range)	7 days HC: yes	Voxel-wise (whole brain)	ECT time 1 vs time 2: decreased D₂ receptor-binding potential in the right rostral anterior cingulate ECT time 1 vs HC: no differences ECT time 2 vs HC: no differences
[carbonyl-¹¹C]WAY100635 measures 5-HT_1A receptor binding
Saijo et al³³ (2010)	9 MDD 45 years (9) 6 male/3 female 9/9 “improved” Patients were treated with SSRI’s	Bitemporal Brief pulse Dose adjusted for age 6–7 treatments (range)	7 days HC: yes	Region of interest analysis	ECT time 1 vs time 2: no differences ECT time 1 vs HC: patients had less 5-HT_1A receptor binding in the midbrain raphe ECT time 2 vs HC: patients continued to have less 5-HT1A receptor binding in the midbrain raphe
Lanzenberger et al³⁴ (2013)	12 MDD 48 years (11) 4 male/8 female 10/12 responders 5-HT1A drugs were exclusionary; other- wise, psychotropic medication had to be at steady state	RUL with a transition to bitemporal if minimal improvement at the sixth treatment (n = 8) Brief pulse Seizure threshold, RUL 3 × threshold 10 treatments (2)	<7 days of completing ECT series HC: no	Voxel-wise (whole brain)	ECT time 2 (pre) vs time 3 (post): widespread decrease in 5-HT_1A receptor-binding potential in cortical and subcortical regions; peak differences in the anterior cingulate (including subgenual), the orbital frontal cortex, insula, hippocampus, and amygdala

Abbreviations: ECT, electroconvulsive therapy; HC, healthy comparison; MDD, major depressive disorder; SD, standard deviation; ^99mTc-HMPAO, technetium-99m-labeled hexamethylpropyleneamine oxime.