The Study Of The Volume And ～1H MRS Of The Hippocampus In Post Traumatic Stress Disorder

Objective: To study the changes of the hippocampus volume and the matebolites with MRI, and to explore the characteristics of changes about the hippocampus volume and metabolites between the typeâ… PTSD patient and the typeâ…¡, analysing the relativity with dissociation.Methods: 30 cases of PTSD and 30 age-matched normal groups (control groups) were examed on a clinical 1.5T MRI/MRS system. Proton sing-voxel spectroscopy imaging (1H-MRS) was obtain from two sides of the hippocampus region. The metabolites included N-acetylaspartate (NAA), creatine and phosphocreatine(Cr), and choline-containing compounds(Cho). The values of NAA,Cr and Cho were calculated by integration of their peaks. PTSD patients were grades by Dissociative Experience Scale(DES).The volume of the hippocampus of the two sides and the brain volume were measured with volume analysis software, and the resulting data were normalizes according to the individual brain volume. Both the value of the metabolites and volume of the hippocampus were compared between control groups and the typeâ… groups, as well as control groups and the typeâ…¡groups respectively. The relativity was analysed between DES scope and NAA/Cr.Results: The volume of the bilateral hippocampus of the typeâ… and the typeâ…¡were smaller than that of control groups(t=2.37,4.20,3.07,4.12,P<0.05). The volumes of the left and right hippocampus were not significant difference between the typeâ… and the typeâ…¡(t=0.55,0.48,P>0.05). NAA/Cr was reduced in PTSD including the typeâ… and the typeâ…¡bilaterally when compared with those of control groups(t=3.63,6.03,7.21,6.60,P<0.05). NAA/Cr in the typeâ…¡was lower than that in the typeâ… bilaterally(t=5.56,2.63,P<0.05). Cho/Cr had no significant difference in the bilateral hippocampus between control groups and PTSD patients including the typeâ… and the typeâ…¡(t=1.03,0.65,0.67,0.35,0.30,0.89,P>0.05). The dissociation in the typeâ…¡PTSD was more than that in the typeâ… PTSD. There was negative relativity between the DES scopes and NAA/Ct. The lower NAA reduced, the higher DES scopes were.Conclusion: The results of this study add support to the view that the hippocampus may participate in the pathophysiology of PTSD. The harm of the hippocampus in the typeâ…¡was more serious than that in the typeâ… .Dissociation was relative with the degree of the hippocampus harmed.