短期戒断的海洛因成瘾者大脑白质完整性的DTI研究

目的运用弥散张量成像(Diffusion Tensor Imagine,DTI)方法观察短期戒断的海洛因成瘾者与正常被试之间的大脑白质完整性的差异,探讨短期戒断的海洛因成瘾者大脑白质微结构改变的特征。材料与方法 25名短期戒断的海洛因成瘾者(HA组)与20名健康对照(HN组)参加本研究。采用GE3.0T磁共振扫描仪进行DTI数据采集,组间各向异性分数(fractional anisotropy,FA)比较采用TBSS方法,组间人口学统计、组间径向弥散(Radial Diffusivty,RD)值和轴向弥散(Axial Diffusivty,AD)值比较采用SPSS13.0软件中的两样本t检验。HA组FA值、AD值和RD值分别与戒断时间、海洛因总时间、海洛因总剂量之间作偏相关分析。结果与HN组相比,HA组多个脑区FA值降低,主要包括胼胝体膝部、胼胝体体部、双侧前辐射冠、左侧后辐射冠、右侧上辐射冠(P0.01,TFCE及FWE校正)。存在FA值差异的脑区内和HN组相比,HA组显示AD值升高,RD值降低(P0.01)。未发现FA值升高区域。HA组FA值、AD值和RD值与戒断时间、海洛因总时间、海洛因总剂量之间无明显相关关系。结论短期戒断的海洛因成瘾者大脑白质多个区域白质微结构损伤,其病理特征可能包括髓鞘损伤和轴索异常改变,损伤区域主要涉及奖赏、认知控制等相关脑区,这可能是短时间戒断的海洛因成瘾者高复吸率的神经生物基础之一。

A DTI study of brain white matter integrity in heroin addicts under short-time abstinence

AbrtractObjective:To investigate the difference of brain white matter integrity between heroin addicts under short-time abstinence and control subjects by a diffusion tensor imagine(DTI)method, and explore the characteristics of changed brain white matter microstructure in heroin addicts under short-time abstinence.Materials and Methods:Twenty-five short-time abstinents and 20 control subjects were recruited. GE 3.0 T magnetic resonance scanner was used for DTI data acquisition. Tract-Based Spatial Statistics (TBSS) were used for fractional anisotropy (FA) comparison between HA group and HN group. Using two samplet test in SPSS 13.0 software to process demographic data, radial diffusivty (RD) value and axial diffusivty (AD) value between HA group and HN group. Partial correlation analysis was used between DTI indices and duration or dose of heroin use and duration of abstinence.Results:Compared with the HN group, signiifcant reduced FA were found in several white matter regions including the genu of corpus callosum, the body of corpus callosum, bilateral anterior corona radiation, the left posterior corona radiata and the right of superior corona radiata in HA group. (P<0.01, corrected by TFEC and FWE) within these regions the HA group showed increased RD and decreased AD. (P<0.01) There were no regions showed significant increase. (P<0.01) There was no significant correlation between each DTI indices and duration or dose of heroin use and duration of abstinence. (P<0.05). Conclusions:White matter integrity signiifcantly reduced in extensive regions among heroin addicts under short-time abstinence. the pathological features may include the
abnormalities both in myelin and axonal. The involved brain areas mainly related to reward and cognitive controls. These ifndings may underline the high relapse rate in heroin addicts under short-time abstinence.