Post-traumatic stress disorder ( PTSD) is an anxiety disorder that can develop following a traumatic event.Neuro-imaging techniques offer a noninvasive means to elucidate the brain circuit underlying PTSD, and may help to find effective biomarkers for diagnosis and treatment evaluation of this disorder.In this article, we review recent brain structural MRI studies in PTSD.Problems of the current research and possible directions for future research are also presented.

Objective To improve diagnosis accuracy of pineocytoma (PC) by joint analysis of CT,MRI imaging features and differential diagnosis with other lesions in pineal region.Methods Totally 6 pineocytoma patients confirmed surgically and pathologically had their clinical history,CT and MRI data collected and analyzed on lesion morphology,cystic solid changes,existence of necrosis,complications of hemorrhage and or calcification,MRI and enhanced scan of solid component,complications with hydrocephalus and etc.Results Plain scan found 1 case of solid nodule and 5 cases of cystic-solid nodules,2 cases with clearly-bordered lesions and 4 one not as well as 4 cases with significant hydrocephalus and 2 ones with light hydrocephalus.Enhanced scan showed 5 cases of moderate to marked enhancement and one case with no obvious enhancement.CT examination proved there were 1 case of calcification and 1 case of hemorrhage.Conclusion Pineocytoma has the characteristics of benign tumor,and has to be differentiated with other tumors frequently occurring in this region in case of obvious clinical signs due to crushing brain parenchyma or blocking aqueduct cerebri by oversized lesions.

Objective To investigate the alteration of the whole brain functional connectivity in patients with minimal hepatic encephalopathy(MHE) by using resting-state functional MRI,and to explore its role in distinguishing the MHE from cirrhotic patients without MHE by using the receiver operator characteristic(ROC) curve.Methods Thirty cirrhotic patients with MHE,32 cirrhotic patients without MHE (non-MHE),and 49 healthy controls underwent standard resting-state functional MRI scan.Whole brain functional connectivities were compared with analysis of variance test to observe the difference among three groups,and then compared with Post-hoc test to investigate the changes between MHE and non-MHE groups.Results There were widespreadly different functional connectivities among three groups.All 115 functional conenctivities showed significant difference among three groups(all P＜0.05).Compared with non-MHE patients,MHE patients showed 6 decreased functional connectivity in the following brain regions (P＜0.05):between left supper temporal gyrus-right orbitofrontal cortex,left Heschl's gyrus-left Rolandic operculum,left Heschl's gyrus-right olfactory cortex,left hippocampus-right amygdala,left putamen-right putamen,and left temporal pole of supper temporal gyrus-right temporal pole of middle temporal gyrus (t=-4.41-3.82,P＜0.01).ROC analysis demonstrated that the left hippocampus-right amygdala had the highest value for differentiating MHE from non-MHE group(AUC=0.78,95％CI 0.66-0.90) with a cutoff value=0.56,sensitivity=73％ and specificity=81％).Conclusion Functional connectivity analysis can be used to observe the functional changes in MHE patient,and has a potential for the early diagnosis of MHE.

Objective To investigate the alteration of the default-mode network (DMN) in the patients with minimal hepatic encephalopathy (MHE) using resting functional MRI, and to explore its underlying clinical significance. Methods Fourteen MHE patients and 14 age-matched normal controls underwent standard resting state functional MRI scan. The components representing DMN were picked out after separation of independent component analysis. One and two sample t-tests were used to observe the changes of DMN in the patients in contrast to the controls. Results Typically spatial distributions of the DMN were found in both MHE patients and controls. Comparison results revealed that there was significantly reduced functional connectivity in the left posterior cingulate cortex, bilateral anterior cingulate cortex, bilateral medial prefrontal cortex, left parahippocampal cortex in MHE patients, while functional connectivity increased in the right precuneus. Conclusion Resting state functional MRI can be used to observe DMN changes in MHE patients. In MHE patients, there is reduced DMN activation in the widespread regions, while the activation of right precuneus increases.

Objective:To investigate the effects and significance of acute and chronic trauma on brain degree centrality (DC) in patients with post-traumatic stress disorder (PTSD) who lost their only child at resting state.Methods:Retrospectively, the study enrolled a total of 51 parents with PTSD, including 35 PTSD parents whose children was lost in emergencies (acute bereaved PTSD group) and 16 PTSD parents whose children was lost of chronic causes such as diseases (chronic bereaved PTSD group). Fifty local adults were also included as healthy controls (HC group). The clinical administered PTSD scale(CAPS) was used to evaluate the severity of the subjects' clinical symptoms.Resting-state functional magnetic resonance imaging(fMRI) data of all subjects were collected and DC values were calculated.SPSS 22.0 software was used for statistical analysis.Covariance analysis was performed among three groups, while post hoc was performed between any two groups.What's more, correlation analyses were utilized between abnormal brain regions and the scores of CAPS.Results:Significant group effects were found in multiple regions, including the right inferior temporal gyrus (MNI: x, y, z=66, -27, -21), right temporal pole (MNI: x, y, z=54, 15, -9), right orbital inferior frontal gyrus (MNI: x, y, z=42, 21, -15), bilateral medial superior frontal gyri (MNI: right x, y, z=6, 63, 12; left x, y, z=-3, 60, 18), left inferior parietal angular gyrus (MNI: x, y, z=-45, -36, 51) and left postcentral gyrus (MNI: x, y, z=-45, -33, 51). Compared with HC group, the DC of two patient groups increased in the right inferior temporal gyrus (MNI: acute x, y, z=63, -27, -21; chronic x, y, z=63, -21, -27); the DC of acute bereaved PTSD group decreased in the right temporal pole (MNI: x, y, z=45, 21, -15) and the right orbital inferior frontal gyrus (MNI: x, y, z=48, 24, -12), while the DC of chronic bereaved PTSD group decreased in the left inferior parietal angular gyrus (MNI: x, y, z=-45, -36, 51) and left postcentral gyrus (MNI: x, y, z=-45, -33, 51). Compared with chronic bereaved PTSD group, the DC of acute bereaved PTSD group increased in the left inferior parietal angular gyrus (MNI: x, y, z=-33, -39, 42) and left postcentral gyrus (MNI: x, y, z=-45, -33, 51), while decreased in the right temporal pole (MNI: x, y, z=51, 12, -9), right orbital inferior frontal gyrus (MNI: x, y, z=42, 21, -15) and bilateral medial superior frontal gyri (MNI: left x, y, z=0, 57, 15; right x, y, z=3, 57, 15). In chronic bereaved PTSD group, the DC of the left postcentral gyrus was negatively correlated with C1 (avoid trauma-related thoughts, feelings) score in CAPS ( r=-0.606, P=0.028). In acute bereaved PTSD group, the DC of the left medial superior frontal gyrus was negatively correlated with D4 (high vigilance) score ( r=-0.416, P=0.020). Conclusion:There exist functional abnormalities of multiple brain regions in acute and chronic bereaved parents with PTSD.The high arousal symptoms of the former may be related with the abnormalities of prefrontal-amygdala neural circuit, while the latter show higher avoidance which may be associated with the dysfunction of somatosensory brain regions such as postcentral gyrus.

Objective:To investigate the effect of coping style on the gray matter volume in patients with post-traumatic stress disorder (PTSD) who lost their only child, and the mediating role of gray matter volume in evaluating the influence of coping style in clinical symptoms of these parents.Methods:A total of 57 parents with PTSD (PTSD group) and 162 parents without PTSD (non-PTSD group) who lost their only child from September 2016 to March 2017 were enrolled from Jiangsu Province, China. Brain MRI data at resting state were collected. Voxel-based multiple regression analysis was performed to confirm the brain areas in which coping style main effect, diagnosis main effect and their interaction had significant influences in gray matter volumes. Correlations among gray matter volume of brain areas related to coping style, coping style scale scores, and clinician-administered PTSD scale (CAPS) scores were analyzed. Structural equation modeling was used to analyze the mediating role of gray matter volume in the influence of coping style in clinical symptoms of parents lost their only child.Results:(1) The coping style main effect did not significantly influence the gray matter volume in all subjects, and the diagnosis main effect had significant influence in gray matter volume in the right lingual gyrus; their interaction had significant influence in gray matter volume in the right peritalar fissure cortex and lingual gyrus. The positive coping style in the PTSD group had significant influence in the gray matter volumes of the right peritalar fissure cortex and lingual gyrus. (2) In the PTSD group, the scores of positive coping style were positively correlated with the gray matter volumes of the right talus fissure and the lingual gyrus ( P<0.05); the scores of positive coping style, and the gray matter volumes of the right talus fissure and the lingual gyrus were negatively correlated with scores of CAPS-C 5 and CAPS-C ( P<0.05). (3) In the PTSD group, positive coping style can positively predict the gray matter volumes of the right talus fissure and the lingual gyrus; the gray matter volumes of the right talus fissure and the lingual gyrus can negatively predict the avoidance-related symptoms. Conclusion:Positive coping style has influence in the gray matter volumes of the right talar fissure and lingual gyrus of PTSD patients lost their only child; and less positive coping style may affect the brain areas related to visual information processing, thus aggravating avoidance-related symptoms of PTSD patients.