ORIGINAL RESEARCH Hippocampal Shape Deformation in Female Patients with Unremitting Major Depressive Disorder

RESULTS: Both hippocampal volumes were small in patients with MDD compared with healthy controls, and the right hippocampal volume was negatively correlated with the number of episodes at marginal significance. Regional shape contractions were found in the ambient gyrus, basal hippocampal head, posterior subiculum, and dorsal hippocampus of the left hemisphere. The right hippocampus showed a similar pattern but was less atrophic compared with the left hippocampus. A negative correlation was found between the HDRS and shape deformation in the CA3, ambient gyrus, posterior subiculum, and gyrus fasciolaris of the left hippocampus. CONCLUSIONS: We showed atrophy and regional shape contractions in the hippocampi of patients with MDD, which were more dominant on the left side. The causes of hippocampal damage could be the hypersecretion of glucocorticoids contributing to neuronal death or the failing of adult neurogenesis in the dentate gyrus. ABBREVIATIONS: AG ambient gyrus; ANCOVA analysis of covariance; Apoe apolipoprotein E; Avr. Surf. average statistic across the surface; BDI Beck Depression Inventory; CA cornu ammonis; FDR false discovery rate; HDRS Hamilton Depression Rating Scale; ICC intraclass correlation coefficient; ICV intracranial cavity volume; LH left hippocampus; MDD major depressive disorder; N# the subject number of each healthy control subject; P# the subject number of each patient with MDD; PDM point distribution model; RH right hippocampus; SCID Structured Clinical Interview for DSM-IV; SPHARM spheric harmonic basis functions; Sub subiculum; TFE turbo field echo; VOI volume of interest