Young Adults With Severe Episode Of Depression Correlation Analysis Of Brain DTI And VBM

Object:The aim of this study was to explore the brain functional and structural pathological mechanism in first-onset major depressive disorder(MDD)by diffusion tensor imaging(DTI) and voxel-based morphometry(VBM) method.Methods:Thirty two first-onset untreated young adult with MDD(according to the diagnosis criteria of CCMD-Ⅲ and DSM-Ⅳ) and thirty two age and gender-matched healthy controls were assessed using17-item Hamilton Depression Rating Scale(HAMD), Hamilton Anxiety Rating Scale(HAMA). HAMD scores were requested>24in patients and≤7in controls. Then,MRI scan were obtained ordering to T2-weigthed images, T1-weigthed images, DTI and3D. Voxel-based morphometrymethods were tested against the two sets of the image of gray matter volume of the brain structure by MR1.Results:Thirty two patients and thirty two controls finished MRI scan. Data could be analyzed finally including thirty twopatients and thirty two controls.The results showed that:1. The sex and age of two groups were no significant difference. For MDD, the average years of education were11.5±3.05years. For the healthy controls(HC), the number of years of education was11.2±2.50years. There were no significant differences in education between the two groups. But the average score of HAMD for MDD was27.0±2.49, and that for the control group was2.79±2.04. There was very significant in HAMD score between the two groups.2. DTI:±Compared with controls. MDD patients exhibited significant decreased fractional anisotropy (FA) values in the two sides of frontal lobe, cingulate, corpus callosum, the two sides of middle temporal gyrus, inferior temporal gyrus and hippocampus.(p<0.05)②Group of patients with depression can be divided into stress and non-stress group line between group analysis, no difference was seen in FA values have statistical significance.③Group of patients with depression can be divided into the high group (HAMD>27) and the low group (HAMD<27) line between group analysis, no difference was seen in FA values have statistical significance.④Group of patients with depression can be divided into highly educated groups (education age≥11years) and lower education groups (education age <11years) line between group analysis, no difference was seen in FA values have statistical significance.⑤Group of patients with depression can be divided into long course groups (course of disease>12months) and short course groups (course of disease≤12months) line between group analysis, frontal lobe(L) and hippocampus(L)differences were seen in FA values have statistical significance.(p<0.05)⑥Depression in patients with left frontal and left hippocampal FA value is negatively related to the course of the disease but nothing to do with the severity of the symptoms.3. Fiber bundle tracking:Choice associated with frontal lobe and hippocampus cingulate main fiber bundle, reconstruction Fornix. Superior Longitudinal fasciculus. Inferior Longitudinal fasciculus, nuciformfasciculus. cingulate. corpus callosum and internal capsule forelimbs.①the fiber bundle numbers of Fornix(L), Superior Longitudinal fasciculus (L), Cingulate bundle(L) and corpus callosum in MDD group are less than which is in HC.②Group of patients with depression can be divided into stress and non-stress group line between group analysis, no difference was seen in fiber bundle numbers have statistical significance.③Group of patients with depression can be divided into the high group (HAMD≥27) and the low group (HAMD<27) line between group analysis, no difference was seen in fiber bundle numbers have statistical significance.④Group of patients with depression can be divided into highly educated groups (education age≥11years) and lower education groups (education age <11years) line between group analysis, no difference was seen in fiber bundle numbers have statistical significance.⑤Group of patients with depression can be divided into long course groups (course of disease>12months) and short course groups (course of disease≤12months) line between group analysis, no difference was seen in fiber bundle numbers have statistical significance.⑥Depression in patients with primary fiber bundle number has nothing to do with the course and the severity of the symptoms 4. VBM:①Compare to healthy controls, the GM volume reduction was found in MDD:Superior Frontal Gyrus(L), Medial Frontal Gyrus(L),Amygdala(L), Superior Temporal Gyrus(R), Insular lobe(L),Lenticular nucleus(L), Cingulate(L) and Caudate nucleus(R).②Group of patients with depression can be divided into stress and non-stress group line between group analysis, no difference was seen in GM volume reduction have statistical significance.③Group of patients with depression can be divided into the high group (HAMD≥27) and the low group (HAMD<27) line between group analysis, no difference was seen in GM volume reduction have statistical significance.④Group of patients with depression can be divided into highly educated groups (education age≥11years) and lower education groups (education age <11years) line between group analysis, no difference was seen in GM volume reduction have statistical significance.⑤Group of patients with depression can be divided into long course groups (course of disease>12months) and short course groups (course of disease<12months) line between group analysis, no difference was seen in GM volume reduction have statistical significance.Conclusion:Major depression in patients with cerebral gray matter volume changes and FA valuesmainly related to frontal lobe, temporal lobe and cingulate brain regions. Many patientswith depression has abnormal brain structure and the links between brain areas, leading to "hemispheric disconnection syndrome", especially the connections in the frontal cortex of a dysfunctional deep cerebral nuclei. That may be the pathogenesis key of depression.