中文摘要：

目的观察美沙酮维持治疗（methadonemaintenancetreatment，MMT）对海洛因成瘾者大脑白质纤维束完整性的影响。方法16例MMT患者（MMT组）和20例匹配的健康对照（C组）参加本研究。对所有被试者进行扩散张量成像（diffusiontensorimaging，DTI）扫描，所得DTI数据进行基于纤维束示踪的空间统计（tract-basedspatialstatistics，TBSS）分析，获得组间各向异性分数（fractionalanisotropy，FA）差异区以及各差异区域内的轴向（axialdiffusivity，AD）和径向（radialdiffusivity，RD）异性分数。对各DTI指标进行两样本检验，并分别与美沙酮和海洛因的使用时间、平均每日剂量作偏相关分析。结果MMT组右侧皮质脊髓束（CST）、左侧上辐射（SCR）和左侧上纵束（SLF）的FA值降低。RD值升高（P〈0．05）。左侧SLF的FA值与MMT每日剂量之间明显负相关（r=-0．719，P=0．006），RD值与MMT每日剂量之间明显正相关（r=0．796，P-0．001）。结论美沙酮可造成以髓鞘破坏为主的大脑白质纤维束结构损伤，这可能构成MMT患者认知功能减退的基础。

英文摘要：

Objective To investigate the effect of methadone maintenance treatment （MMT） on the white matter integrity of for- mer heroin abusers. Methods 16 MMT patients and 20 matched healthy controls were enrolled in this study. The subjects under- went diffusion tensor imaging （DTI） scan and the DTI data were analyzed using tract-based spatial statistics to get significantly dif- ferential clusters of fractional anisotropy （FA） between groups, and the axial diffusivity （AD）, radial diffusivity （RD） in each clus- ter were extracted. Each DTI index was compared through two-sample t-test. Partial correlation analysis was used to measure the relativity between DTI index and the duration of heroin use, the everyday dose of heroin, the duration of MMT as well as the every- day dose of MMT. Results The MMT patients showed significantly greater FA and decreased RD value in the right eortieospinal tract （CST）, left superior corona radiata （SCR） and superior longitudinal fasciculus （SLF）. There was significantly negative correla- tion between FA and everyday dose of methadone （r=-0.719, P=0. 006） , positive correlation value between RD and everyday dose of methadone （r= 0. 796,P=0. 001） in the cluster of left SLF. Conclusion Methadone has deleterious effect mainly on the myelin of white matter tract, which may underlie the cognative function decrease of MMT patients.