首发未用药精神分裂症患者的白质纤维及皮质结构的MRI研究

A MRI Study of White Matter Fibers and Cerebral Cortex in Medical- naive First- episode Schizophrenia

目的研究首发未用药精神分裂症患者白质纤维及皮质结构的异常改变。方法对36例首发未用药精神分裂症患者和41名健康对照进行全脑弥散张量成像(DTI)及脑结构成像。通过基于纤维束的空间体积分析(TBSS)比较两组间白质纤维FA值的差异。使用基于表面的分析方法(FreeSurfer)进行两组间皮质结构的比较。结果 TBSS分析显示患者组中双侧上纵束、双侧后扣带束以及左侧皮质脊髓束的FA值减低。FreeSurfer分析显示,患者组皮质厚度减低的区域有:左侧额上回、额中回、眶回、中央前回、颞上回、颞中回、颞下回、顶上小叶、顶下小叶、中央后回、楔前叶、侧枕叶、楔叶、扣带回及右侧额上回、颞中回、颞下回、岛叶、缘上回、中央后回、扣带回;表面积减小的区域有左侧额上回、额中回、眶回、中央前回、颞下回、颞中回、颞上回、顶上小叶、顶下小叶、缘上回、中央后回、岛叶、楔前叶、扣带回及右侧额中回、顶上小叶、颞中回、岛叶、中央前回、额上回。结论首发未用药精神分裂症患者存在白质纤维束及皮质结构的多区域异常,且两者在解剖关系上具有相关性;灰质结构异常可能是精神分裂症发病的主要原因。

Objective To investigate the abnormalities of the white matter fibers and gray matter in medical-naive schizophrenia patients.Methods Sixty-two first episode patients and 54 controls matched on age,sex,years of education and laterality index underwent diffusion tensor imaging.Voxelwise group comparison of white matter fractional anisotropy （FA） was performed using tract-based spatial statistics （TBSS）.Comparison of gray matter structures was performed using surface-based morphometry （FreeSurfer）.Results Compared with control subjects,patients with schizophrenia showed decreased FA in three clusters（P ＜ 0.05）,including superior longitudinal fasciculus（SLF） and posterior cingulum bundle（PCB） bilaterally and corticospinal tract（CST） in the left hemisphere.FreeSurfer showed that patients group showed reduced the cortical thickness in the superior frontal gyrus,middle frontal gyrus,orbitofrontal gyrus,medial frontal gyrus,superior temporal gyrus,middle temporal gyrus,inferior temporal gyrus,superior parietal lobule,inferior parietal lobule,postcentral gyrus,precuneus,lateral occipital,precuneus,cingulate gyrus in the left hemisphere and the frontal gyrus,middle temporal gyrus,inferior temporal gyrus,insula,postcentral gyrus,supramarginal gyrus,cingulate gyrus in the right hemisphere; and reduced cortical surface area included frontal gyrus,middle frontal gyrus,orbitofrontal gyrus,medial frontal gyrus,inferior temporal gyrus,middle temporal gyrus,superior temporal gyrus,superior parietal lobule,inferior parietal lobule,supramarginal gyrus,postcentral gyrus,insula,precuneus,cingulate gyrus in the left hemisphere and middle frontal gyrus,superior parietal lobule,middle temporal gyrus,insula,medial frontal gyrus,superior frontal gyrus in the right hemisphere.Conclusion Disturbed white matter connectivity and aberrant cortical structures in multi-regions exist in medical-naive first-episode schizophrenia,and the two have anatomical correspondences to some extent.Abnormalities in cortical structures may be the primary pathogenesis of the outbreak of schizophrenia.