Hippocampal subfield-specific connectivity findings in major depressive disorder: A 7 Tesla diffusion MRI study.
Hippocampal subfield-specific connectivity findings in major depressive disorder: A 7 Tesla diffusion MRI study.
复制标题
重度抑郁症中海马亚区特异性连接的发现：一项 7 特斯拉扩散 MRI 研究。
DOI：
10.1016/j.jpsychires.2019.02.008
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发表时间：
2019
影响因子：
4.8
通讯作者：
Balchandani,Priti
中科院分区：
文献类型：
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作者：
Rutland,JohnW;Brown,Stephanie;Verma,Gaurav;Feldman,RebeccaE;Sharma,Himanshu;Markowitz,Matthew;Schneider,Molly;Delman,BradleyN;Murrough,James;Balchandani,Priti
目的扩散磁共振成像 (dMRI) 能够对体内白质 (WM) 结构进行非侵入性表征。先前的研究表明，某些 WM 束可能会受到重度抑郁症 (MDD) 的影响，然而，海马亚区特异性 dMRI 测量尚未在 MDD 中进行探索。我们使用7特斯拉dMRI来研究MDD患者海马亚场连接的差异。方法对18名MDD患者和18名匹配的健康志愿者进行7特斯拉MRI。海马结构按子区域进行分割，并进行纤维束成像以确定患者和对照组的流线计数（SC）、各向异性分数（FA）和平均扩散率（MD）。显着的亚域连通性测量也与抑郁症发病年龄相关。结果与对照组相比，MDD 患者左侧齿状回分子层 SC 减少（p<0.001）。左侧齿状回的 SC 计数与发病年龄呈正相关 (p<0.05)。 MDD 患者左侧 (p=0.0001) 和右侧 (p<0.001) 菌毛的流线中观察到 MD 增加。结论 菌毛束 MD 增加表明主要海马输出门的神经元膜受损。齿状回的 SC 减少表明正常细胞过程（例如神经发生）受到破坏。这些发现可能对识别重度抑郁症的生物标志物和阐明抑郁症的神经生物学基础具有重要意义。
ObjectiveDiffusion magnetic resonance imaging (dMRI) enables non-invasive characterization of white matter (WM) structuresin vivo. Prior studies suggest that certain WM tracts may be affected in major depressive disorder (MDD), however, hippocampal subfield-specific dMRI measures have not yet been explored in MDD. We use 7 Tesla dMRI to investigate differences in hippocampal subfield connectivity of MDD patients.MethodsEighteen MDD patients and eighteen matched healthy volunteers underwent 7 Tesla MRI. The hippocampal formations were segmented by subfields and tractography was performed to determine streamline count (SC), fractional anisotropy (FA), and mean diffusivity (MD) in patients and controls. Significant subfield connectivity measures were also correlated with age at depression onset.ResultsCompared with controls, MDD patients exhibited reduced SC in the molecular layer of the left dentate gyrus (p < 0.001). SC count in the left dentate gyrus was shown to positively correlate with age at disease onset (p < 0.05). Increased MD was observed in streamlines emanating from both the left (p = 0.0001) and right (p < 0.001) fimbriae in MDD patients.ConclusionsIncreased MD of tracts in the fimbriae suggests compromised neuronal membranes in the major hippocampal output gate. Reduced SC of the dentate gyri indexes a disruption of normal cellular processes such as neurogenesis. These findings may have significant implications for identifying biomarkers of MDD and elucidating the neurobiological underpinnings of depression.