目的采用静息态功能性磁共振成像的低频振幅技术,探讨海洛因依赖者脑活动的神经机制及其意义。方法运用功能性磁共振技术观察海洛因成瘾者的脑血氧水平依赖信号的改变;对15例海洛因海洛因依赖者和15名正常志愿者进行静息态数据采集,然后运用低频振幅算法对采集后的静息态数据进行分析,得到每个被试的低频振幅统计图,最后对两组进行双样本t检验,以P〈0.05,t〉2.060为阈值显示海洛因依赖者相对于正常人ALFF增高和减弱的区域。结果海洛因依赖组和正常对照组相比ALFF减弱的脑区分布在右颞叶(45,-30,-21)、左侧海马(-36,-33,-6)、右侧丘脑(24,-12,27)、左侧后扣带回(-15,-54,24)、右侧顶叶及楔前叶(21,-51,36)、右侧顶下小叶(45,-42,63)、右侧额叶背外侧面(21,-48,78);而海洛因依赖组在左侧前额叶(0,39,72)ALFF明显高于对照组。结论海洛因依赖者静息状态下表现出异常的脑功能活动方式,这些异常的活动可能与海洛因依赖的产生、维持及戒断后复吸密切相关。
Objective To study the changes of amplitude of low-frequency fluctuation (ALFF) of the resting state fMRI in heroin abuser (HD), and discussed its underlying neurophysiological mechanism. Methods The resting state fMRI data of 15 heroin abusers and 15 normal volunteers were analyzed by ALFF. The amplitude of the blood oxygenation level dependent activation of the resting state brain was investigated. The brain structures showing increased and decreased ALFF in TLE patients were demonstrated by comparing to normal sub- jects with 2-sample t -test with threshold of P〈 0. 05. Results Compared with normal subjects,the regions showing decreased ALFF in HD patients were distributed in right temporal lobe(45, -30, -21 ) ,left hippocampus( -36, - 33, - 6), right thalamus ( 24, - 12,27 ), left posterior cingulum gyms ( - 15, - 54,24 ), right parietal lobe / precuneus ( 21, - 51,36 ) , right inferior parietal lobule ( 21 , - 48,78 ) and dorsal lateral aspect of the right frontal lobe ( 21, - 48,78 ), while ALLF of left (45, - 42,63 ) lateral frontal cortex (0,39,72) in HD patients was significantly higher. Conclusion HD shows abnormal brain functional organization in resting state, which may play an important role in the production, maintenance and relapse after withdrawal of heroin abuse.