基于TBSS方法评价甲基苯丙胺依赖者长期戒断后脑白质扩散张量的变化

White Matter Diffusion Tensor Change After Long-Term Methamphetamine Abstaining Addicts Assessed by Tract Based Spatial Statistics

目的探讨甲基苯丙胺(MA)依赖者长期戒断后脑白质微观结构的改变。资料与方法对29例接受长期戒断的MA患者与31名正常对照进行全脑扩散张量成像扫描,采用基于纤维束示踪的空间统计(TBSS)方法,比较不同脑区各向异性分数(FA)值和平均扩散率(MD)值的差异,将异常脑区的FA值和MD值与认知功能测量进行相关分析。结果戒断组和对照组认知执行功能测试结果差异无统计学意义(P>0.05);与对照组比较,戒断组多个脑区FA值较低,多个脑区MD值较高(P<0.05)。左侧丘脑前辐射FA值与连线A时间呈正相关(r=0.448,P<0.05),左侧额枕下束FA值与连线A抬笔数呈正相关(r=0.411,P<0.05),右侧丘脑MD值(r=-0.452)、左侧皮质脊髓束MD值(r=-0.486)、右侧海马MD值(r=-0.381)、右侧大脑上纵束FA值(r=-0.277)与连线A时间均呈负相关(P均<0.05),左侧丘脑前幅射MD值与连线A正确数呈负相关(r=-0.320,P<0.05),右侧大脑上纵束(颞叶部分)MD值与连线A正确数呈正相关(r=0.259,P<0.05)。结论戒断组经长期戒断后多个脑区脑白质微结构仍存在异常,扩散张量成像可为长期戒断MA脑微观结构异常提供影像学证据。

Purpose To investigate the changes of brain white matter microstructure in methamphetamine(MA)after a long-term withdrawal.Materials and Methods The whole-brain diffusion tensor imaging(DTI)scan was conducted to 29 patients with long-term MA withdrawal and 31 normal controls.Spatial statistics based on tract based spatial statistics(TBSS)was adopted,differences between fractional anisotropy(FA)and mean diffusivity(MD)values in different brain regions were compared,moreover,correlation between FA and MD values from the abnormal brain and cognitive function measurement was analyzed.Results There was no statistical significance in differences of cognitive executive function test results between long-term withdrawal group and control group(P>0.05);compared with control group,some brain areas FA of the patients in long-term withdrawal group were reduced;some brain areas MD were increased.FA value of left anterior thalamic radiations was positively correlated with line A time(r=0.448,P<0.05).FA value of left inferior front occipital fasciculus was positively correlated with the number of lifting pens of line A(r=0.411,P<0.05).MD value of right thalamus(r=-0.452),left tractus corticospinalis(r=-0.486),right hippocampus(r=-0.381)and FA value of right superior longitudinal fasciculus cerebrum(r=-0.277)were negatively correlated with line A time(P<0.05).MD value of left anterior thalamic radiations was negatively correlated with correct numbers of line A(r=-0.320,P<0.05),MD value of right superior longitudinal fasciculus cerebrum(temporal lobe)was positively correlated with correct numbers of line A(r=0.259,P<0.05).Conclusion After a long-term withdrawal,there are still abnormal brain white matter microstructures in many brain regions for MA,and DTI could provide imaging evidence for structure abnormity of long-term withdrawal MA microstructures.