Impaired robust interhemispheric function integration of depressive brain from REST-meta-MDD database in China.

BACKGROUND: Recently, functional homotopy (FH) architecture, defined as robust functional connectivity (FC) between homotopic regions, has been frequently reported to be altered in MDD patients (MDDs) but with divergent locations. METHODS: In this study, we obtained resting-state functional magnetic resonance imaging (R-fMRI) data from 1004 MDDs (mean age, 33.88 years; age range, 18-60 years) and 898 matched healthy controls (HCs) from an aggregated dataset from 20 centers in China. We focused on interhemispheric function integration in MDDs and its correlation with clinical characteristics using voxel-mirrored homotopic connectivity (VMHC) devised to inquire about FH patterns. RESULTS: As compared with HCs, MDDs showed decreased VMHC in visual, motor, somatosensory, limbic, angular gyrus, and cerebellum, particularly in posterior cingulate gyrus/precuneus (PCC/PCu) (false discovery rate [FDR] q < 0.002, z = -7.07). Further analysis observed that the reduction in SMG and insula was more prominent with age, of which SMG reflected such age-related change in males instead of females. Besides, the reduction in MTG was found to be a male-special abnormal pattern in MDDs. VMHC alterations were markedly related to episode type and illness severity. The higher Hamilton Depression Rating Scale score, the more apparent VMHC reduction in the primary visual cortex. First-episode MDDs revealed stronger VMHC reduction in PCu relative to recurrent MDDs. CONCLUSIONS: We confirmed a significant VMHC reduction in MDDs in broad areas, especially in PCC/PCu. This reduction was affected by gender, age, episode type, and illness severity. These findings suggest that the depressive brain tends to disconnect information exchange across hemispheres.

Pharmacotherapy response and regional cerebral blood flow characteristics in patients with obsessive-compulsive disorder.

OBJECTIVE: To analyze the correlation between the pharmacotherapy response and the characteristics of the pre-treatment regional cerebral blood flow (rCBF) in patients with obsessive-compulsive disorder (OCD). METHODS: Single-photon emission-computed tomography (SPECT) was used to determine the pre-treatment rCBF in 30 OCD patients and 30 normal controls. Based on their clinical remission response, the subjects were divided into two groups: selective serotonin reuptake inhibitors (SSRIs) and SSRIs plus quetiapine. The subjects with clinical remission response were identified after treatment for a period of 24 weeks, and the rCBF imaging data were processed using statistical parametric mapping (SPM) software with two-sample Z-tests. RESULTS: Nineteen OCD patients who achieved clinical remission were included in the study. Increased rCBF in forebrain regions, including the frontal lobe, cingulate gyrus, hypothalamus, and basal ganglia, was found in 11 responders to SSRIs compared to normal control patients. The eight SSRI plus quetiapine responders exhibited a decrease in rCBF within posterior brain regions, including the parietal lobe, cerebellar vermis, and occipital lobe, and an increase in rCBF in the frontal lobe, thalamus, basal ganglia, and cerebellum tonsil compared to normal control patients. CONCLUSIONS: The characteristics of increased rCBF in forebrain regions and decreased rCBF in posterior brain regions before treatment of OCD patients was a potentially predictor of treatment response to guide treatment options.

[Change characteristics of regional cerebral blood flow and curative efficacy in patients with obsessive-compulsive disorder].

OBJECTIVE: To explore the change characteristics of regional cerebral blood flow (rCBF) and its correlation with curative efficacy in patients with obsessive-compulsive disorder (OCD). METHODS: The images of rCBF and computed tomography (CT) were acquired from 30 OCD and 30 normal controls by single photon emission computed tomography (SPECT) and CT. The tomographic data of rCBF were normalized, smoothed and statistically processed with the statistical parametric mapping (SPM) software with two-sample Z-test. And the OCD grade was evaluated with the Y-BOCS at pre- and post-medication. RESULTS: The abnormal results of CT were not found. The SPM Z-test showed that the sections of higher rCBF in the OCD patients were predominantly located in basal ganglia and occipital lobe compared with the normal controls (P < 0.001). The scores of Y-BOCS in 30 patients were markedly lower at post-medication than those at pre-medication (24 ± 7 vs 11 ± 6, P < 0.001). At post-medication, the scores of Y-BOCS with higher rCBF in basal ganglia and occipital lobe were higher than those in basal ganglia or occipital lobe (P < 0.05). CONCLUSION: The OCD patients have higher rCBF in basal ganglia and occipital lobe. The curative efficacy of OCD with higher rCBF in basal ganglia and occipital lobe is worse than that in basal ganglia or occipital lobe.

Neurocognitive dysfunction and regional cerebral blood flow in medically naïve patients with obsessive-compulsive disorder.

Previous research characterizes obsessive compulsive disorder (OCD) as a complex neurobehavioral disorder that may have multiple etiologies ( den Braber et al., 2008 ). This study analyzed neurocognitive function and change in regional cerebral blood flow (rCBF) to characterize OCD. Neurocognitive function and rCBF were examined in medically naïve patients with OCD and contrasted with controls. Results of this study indicated that the neurocognitive functions impaired in OCD are memory, attention, and executive function, which are primarily associated with the frontal and occipital lobes. Dysfunction in the basal ganglia and occipital lobes were associated with OCD and may be an etiological factor in the disorder.