Starting In Major Depressive Disorder In Patients With Cerebral White Matter Microstructure Diffusion Tensor Imaging Study

Objective:To explore the microstructural alterment of whole-brain white matter by diffusion tensor imaging in the first-episode young adults with major depressive disorder and the relationship between the mean FA values of patients and illness course、severity of disease as well as intial age.Methods:Enroll seventy-one first-episode young adults with major depressive disorder and forty-five healthy pepole consisted in forty-one pairs(22males.19females) controlled gender and age. Major depressive disorder underwent Executive handbook for the structured clinieal interview for DSM—Ⅳ axisl disorders(SCIDI/P)、Hamilton Depression scale(HAMD)、Self-Rating Depression Scale(SDS)、Hamilton Anxiety scale(HAMA). In major depressive disorders HAMD sorces were requested>17, HAMA<14, but HAMD<7, HAMA<7, and SDS<30in controls. Diffusion tensor imaging is employed to examine the white matter alterment in both groups and review fractional anisotropy as index. Diffusion-tensor images were analyzed using the brain fMRI softwarelibrarySeveral FSL(FMRIB Software Library, http://www.fmrib.ox.ac.uk/fsl) tool packages were used for data processing. After the eddycurrent correction, the diffusion tensor was calculated and the resulting FA images were further processed using automated Tract-Based Spatial Statistics (TBSS) which performs voxel-by-voxel whole-brain analysis. After aligning all of the individual FA images to the standard space template using nonlinear registration, the mean FA image was derived and thinned to generate a mean skeleton embodying the center of all tracts derived from the whole group. An FA threshold of0.20or higher was set to exclude peripheral tracts. Finally, each subject’s aligned FA images were projected onto this template skeleton.Mean FA values of MDD groups and controls was employed threshold-Free Cluster Enhancement and attract mean FA of MDD. Clinical association of the FA values with illness course, severity of disease and intial age was examined by using Spearman’s correlation analysis(two tail, p<0.05).Results:1)The MDD exhibite signifieantly greater mean FA values than healthy subjects in white matter of the left superior longitudinal fasciculus.2) The course of the illness、severity of disease、intial age of patient isn’t significantly correlated to mean FA value of MDD.Conclusions:1) the microstructural of whole-brain white matter in first-episode, major depressive disorder was altered.2) There may be compensatory regeneration of nerve fibers in first-episode treatment-naive young adults of major depressive disorders. 3) the microstructural of whole-brain white matter of first-episode treatment-naive young adults with major depressive disorder wasn’t significantly correlated to the course of the illness、severity of disease、intial age of patients.