低频振幅算法功能磁共振成像观察屈光参差性弱视患者脑活动

目的 应用基于低频振幅(ALFF)算法的功能磁共振成像(fMRI)观察屈光参差性弱视患者脑活动的变化。方法 对9例左眼单眼屈光参差性弱视患者(弱视组)和12名健康志愿者(对照组)在黑白棋盘格刺激下行fMRI,应用t检验对ALFF脑图进行组间和组内统计学分析。结果 1例弱视组患者数据在预处理后被剔除。左眼接受刺激时,弱视组较对照组左侧舌回、右侧枕中回、右侧中央前回、左侧后扣带回、左侧顶上小叶、左侧楔前叶和楔叶等区域ALFF减弱,左侧额中间回、左侧额上回、左侧颞上回、右侧杏仁体和右侧壳核等区域ALFF显著增强;右眼接受刺激时,弱视组较对照组胼胝体和左侧颞中回ALFF减弱,双侧枕叶、右侧额中回和右侧尾状核等区域ALFF显著增强。弱视组中,与右眼接受视觉刺激时比较,左眼接受视觉刺激时右侧额下回、左侧尾状核、丘脑及前扣带回等脑区ALFF显著增强,双侧枕叶ALFF显著减弱。结论 任务状态下基于ALFF算法的fMRI不仅可反映弱视患者视皮层的功能损害,还可反映多脑区神经活动的变化。

Observation of brain activity on anisometropic amblyopia with fMRI based on amplitude of low frequency fluctuation

Objective To observe the changes of brain activity on human with anisometropic amblyopia with fMRI based on amplitude of low-frequency fluctuation (ALFF). Methods Nine patients with anisometropic amblyopia of the left eye (amblyopia group) and twelve healthy subjects (control group) underwent fMRI scanning during visual stimuli of white-black chessboard. After data preprocessing, ALFF was obtained and compared intra- and inter-groups with t-test. Results One patient with amblyopia group was excluded after data preprocessing. In amblyopia group, when left eyes were stimulated, ALFF decreased in the left lingual gyrus, right occipital lobe, right precentral gyrus, left posterior cingulate gyrus, left superior parietal lobule as well as left precuneus and cuneus,but increased in the left middle frontal gyrus, left superior frontal gyrus, left superior temporal gyrus, ritht amygdaloid body and right putamen; Meanwhile, when right eyes were stimulated, ALFF decreased in the corpus callosum and left middle temporal gyrus,but increased in the bilateral occipital lobes, right middle frontal gyrus and right caudate nucleus compared with that of control group. In amblyopic group, compared with right eye, when left eye was stimulated, ALFF decreased in the bilateral occipital lobes and increased in the right inferior frontal gyrus, left caudate nucleus, thalamus and anterior cingulate gyrus. Conclusion The method of detecting ALFF for the task-fMRI allows direct observation of the neural activity changes in multiple brain areas of human with amblyopia.