缓解期双相情感障碍Ⅰ型患者白质纤维结构异常的扩散张量成像研究

A diffusion tensor imaging study for white matter microstructural abnormalities in patients with type-Ⅰbipolar disorder in euthymic period

目的:探讨缓解期双相情感障碍(BD)Ⅰ型患者脑白质神经纤维束的改变,及患者认知功能与脑白质病变的关系。方法:采用汉密尔顿抑郁量表(HAMD),杨氏躁狂量表(YMRS)和重复性成套神经心理状态量表(RBANS)对患者进行入组的筛查与认知评估。应用3.0T磁共振仪对76例缓解期BD-Ⅰ型患者以及66例年龄、性别相匹配的健康志愿者(对照组)行DTI扫描,使用PANDA软件包提取全脑白质纤维束的各向异性分数(FA)和平均扩散率(MD),采用独立样本t检验进行组间差异比较,及Pearson相关分析探讨BD组中各纤维束的FA与临床可重复神经心理状态测验(RBANS)评分间的相关性。结果:相较于对照组,BD-Ⅰ型组的左、右侧钩束、右侧上纵束、右侧下额枕束及左侧毯束的FA值降低,MD值升高,差异均具有统计学意义(P<0.01)。BD-Ⅰ型组的左、右侧钩束、右侧上纵束和右侧下额枕束的FA值与RBANS量表评估的总分及即刻记忆、延迟记忆、视觉广度和注意力四项因子的评分均具有正相关关系(r=0.32~0.44,P均<0.05)。结论:缓解期双相障碍BD I型患者多个脑白质神经纤维束微观结构受损,且与认知功能改变相关。

Objective:The aim of this study was to investigate the changes of white matter fiber bundles in patients with bipolar disorder typeⅠ(BD-Ⅰ)in euthymic period,and the relationship between cognitive impairment and white matter lesions.Methods:Hamilton depression scale(HAMD),Young mania rating scale(YMRS)and repeatable battery scale for the assessment of neuropsycholo-gical status(RBANS)were used for screening and cognitive assessment.76 patients with BD-Ⅰin euthymic period and 66 matched healthy subjects(HS group)were recruited and underwent diffusion tensor imaging at a 3.0T magnetic resonance scanner.The DTI data were post-processed by the PANDA software package to extract the diffusion parameters of fiber bundles in white matter of the whole brain,including factional anisotropy(FA)and mean diffusivity(MD).Independent-sample t-test was used to analyze the inter-group difference of factional anisotropy(FA)and mean diffusivity(MD),while Pearson correlation analysis was performed to analyze the correlation between FA of each white matter fiber and RBANS scores.Results:Compared with HS group,significant decrease of FA values and increase of MD values in bilateral uncinate fasciculus(UF),right superior longitudial fasciculus(SLF),right inferior fronto-occipital fasciculus(IFOF)and left tapetum(TAP)in BD-Ⅰgroup were observed,and the differences were statistically significant(all P<0.01).FA values of the bilateral UFs,right SLF,right IFOF and left TAP were positively correlated with part of the RBANS results(r=0.32~0.44,all P<0.05),including total score and scores of four index(immediate memory,delayed memory visuospatial-constructional,and attention).Conclusion:The patients with BD typeⅠin euthymic period have cognitive impairment in a certain extent,which may be related to white matter lesions.