学位级别】医学博士

【论文完成日期】2000-4-30

【论文中文题名】精神分裂症患者磁共振弥散张量研究

【论文外文题名】Magnetic Resonance Diffusion Tensor Imaging Studies in patients with schizophrenia

【论文著者】姓名：王菲 wang fei

【论文著者】学号：B10199766

【论文著者】系别：精神卫生研究所

【论文著者】专业：精神病与精神卫生学

【论文著者】研究方向：精神病学

【指导教师】姓名：张岱 zhang dai

【指导教师】学校：北京大学医学部

【指导教师】系别：精神卫生研究所

【指导教师】专业：精神病与精神卫生学

【中文文摘】实验1 目的 磁共振弥散张量成像能够非损伤性的检测组织中的水分子弥散程度，因而可以直接反映白质纤维束的结构完整性。部分各项异性值是弥散张量成像反映水分子弥散程度的一个公认的指标。本研究的目的是希望了解精神分裂症患者全脑白质的完整性是否受损。 方法 应用磁共振弥散张量成像检测了30名精神分裂症患者和19名正常对照者，进行了全脑扫描，对多个脑区的白质纤维进行分析测量，使用部分各项异性值作为指标。 结果 重复测量方差分析表明，部分各项异性值只是在精神分裂症患者的扣带束前部与正常人有统计学上的显著性差异，其他部位：额叶，颞叶，顶叶，枕叶，胼胝体膝部和压部，内囊前肢和后肢未见统计学上的显著差异。 结论 精神分裂症患者存在扣带束前部的白质完整性的损害，其他脑区未见白质完整性的损害。 实验2 目的 本课题的初步研究首次应用磁共振弥散张量成像的方法，发现精神分裂症患者存在扣带前部的损害。由于扣带束是一个较大的区域，全脑的磁共振扫描对此区域产生了较大的部分容积效应，因而，本实验改进了磁共振弥散张量成像的扫描方法，进一步证实和探讨精神分裂症患者扣带束前部和后部损害的特点。 方法 21名精神分裂症男性患者和20名男性正常对照完成了针对扣带束的磁共振弥散张量成像的扫描。使用部分各项异性值作为指标。 结果 重复测量方差分析表明，男性精神分裂症患者扣带束前部的部分各项异性值与正常人比较，在左侧和右侧都发现了统计学上的显著性下降，同时见到左侧优势的降低。扣带回后部未见两组之间的统计学差异。 结论 对于脑内较大的白质纤维扣带束，精神分裂症患者存在前部的白质完整性的损害，而后部未见损害 实验3 目的 许多研究证实了小脑参与了高级的认知活动。精神分裂症患者存在认知损害。小脑上脚和中脚是小脑与其他脑区联系的主要纤维，在本研究中，通过弥散张量成像的方法，探讨精神分裂症患者小脑中脚和上脚的白质纤维完整性的情况。 方法 29名男性精神分裂症患者和20名男性正常人完成了磁共振弥散张量成像的扫描。部分各项异性值和平均弥散系数作为本研究的检测指标。 结果 独立样本t检验显示，男性精神分裂症患者与男性正常对照之间小脑上脚和中脚的部分各项异性值和平均弥散系数无统计学上的显著性差异。 结论 男性精神分裂症患者的小脑上脚和中脚没有白质完整性的损害。

【外文文摘】Study 1 Objective Diffusion tensor imaging (DTI) can non-invasively examine the molecular diffusion of water invivo and directly reflects the anatomical integrity of neural fibers in white matter. Fractional anisotropy (FA) can be calculated from DTI data, and utilized to evaluate white matter integrity. Method DTI was performed on 30 patients with schizophrenia and 19 healthy controls, and their FA values were subsequently measured in multiple brain regions. Results Statistical analyses revealed that FA values were decreased in the anterior cingulum of schizophrenia subjects. There were no significant differences between patients and controls in any other regions. Conclusions This study supports the hypothesis that schizophrenia is associated with abnormal white matter integrity of the anterior cingulum. Study 2 Objective This study used diffusion tensor imaging to examine fractional anisotropy in the anterior cingulum and posterior cingulum bundles in patients with schizophrenia. Method Twenty-one male patients and 20 healthy comparison men were studied. Results Reduced fractional anisotropy was seen for both sides of the anterior cingulum in the schizophrenia patients, who also exhibited less left-greater-than-right asymmetry in the anterior cingulum than was seen in the comparison subjects. Conclusions The findings suggest structural disconnections in the anterior cingulum in patients with schizophrenia. Study 3 Objective Many studies have confirmed that the cerebellum takes part in higher-order cognitive coordination; profound fibers projecting to and from the cerebellum underlie its cognitive function. Since the superior and middle cerebellar peduncles are the main pathways of neural fibers in the cerebellum, these structures became the focus of our interest in evaluating the cognitive dysfunction reported in schizophrenia. Method Diffusion tensor imaging (DTI) was used to examine the anatomical integrity of the neural fibers in the superior and middle cerebellar peduncles. DTI was performed on 29 patients and 20 normal controls; we subsequently calculated the fractional anisotropy and mean diffusivity in these regions. Results Statistical analysis revealed that there was no significant difference between patients with schizophrenia and our matched control group. Conclusions No structural abnormalities were detected in the white matter of the superior and middle cerebellar peduncles.