应用静息态功能磁共振成像分数低频振幅技术观察脑梗死患者大脑基线功能的变化

目的 应用静息态功能磁共振成像分数低频振幅(fALFF)技术,探讨脑梗死患者大脑基线功能的变化。方法 采用fALFF算法观察右侧皮层下脑梗死患者脑血氧水平依赖信号的变化。收集10例脑梗死患者的亚急性期和慢性期静息态功能磁共振成像数据,并选择10名年龄、性别匹配的健康志愿者作为对照组,计算受试者的fALFF值,观察患者在不同时期fALFF相对正常人升高和降低的区域。结果 与对照组相比,脑梗死的亚急性期患侧楔前叶、扣带回前部及双侧前额皮质内侧的fALFF降低,双侧上纵束区域的fALFF显著降低;边缘叶fALFF信号紊乱而健侧杏仁核fALFF升高;双侧额下回、直回、颞上回、颞中回、颞下回、梭状回和患侧颞横回fALFF升高;慢性期双侧楔前叶fALFF升高。结论 fALFF功能磁共振成像技术可对脑梗死的脑功能损伤和预后提供有价值的信息。

Observing the activity change of the baseline brain in cerebral infarction with fractional amplitude of low-frequency fluctuation

Objective To investigate the activity change of the baseline brain in patients with cerebral infarction with fractional amplitude of low-frequency fluctuation (fALFF) of the resting-state fMRI. Methods Changes of blood oxygen level dependent signal in right subcortex of patients with cerebral infarction were observed with fALFF. The resting-state fMRI data of 10 patients with cerebral infarction under subacute stage and chronic phase and 10 healthy volunteers in the control group were analyzed. All data of fALFF were analyezd. Results Compared to control group, in subacute stage, fALFF decreased in ipsilateral precuneus, anterior cingulated cortex and bilateral medial prefrontal cortex, while significantly decreased in bilateral superior longitudinal fasciculus. The limbic system mainly showed signal disorders besides fALFF increasing in contralateral amygdala. fALFF increased in bilateral inferior frontal gyrus, rectal gyrus, superior temporal gyrus, middle temporal gyrus, inferior temporal gyrus, fusiform gyrus and ipsilateral transverse temporal gyrus. In chronic phase, fALFF of bilateral precuneus increased. Conclusion The method of fALFF can provide valuable information of cerebral damage of patients with cerebral infarction and evaluate the prognosis.