正常眼压性青光眼的rsfMRI-fALFF研究及其与OCT及视野相关性分析

Study and correlative analysis between rsf MRI-f ALFF and OCT,visual field in normal tension glaucoma

目的利用静息态功能磁共振成像比率低频振幅(resting state f MRI-fractional amplitude of low frequency fluctuation,rsf MRI-f ALFF)研究正常眼压性青光眼(normal tension glaucoma,NTG)脑功能的改变,研究其与光学相干断层扫描(optical coherence tomography,OCT)及视野的相关性,探索NTG病理生理机制。方法选取NTG患者20例(NTG组),以及20名与NTG组在性别、年龄、受教育程度等相匹配的健康志愿者(正常对照组),完成全脑静息态功能磁共振扫描,获取被试全脑静息态数据,利用REST软件进行静息态数据预处理,对比NTG组与正常对照组全脑比率低频振幅(fractional amplitude of low frequency fluctuation,f ALFF)改变的脑区,检验f ALFF改变的脑区与患者OCT及视野的相关性。结果与正常对照组比较,NTG组右侧脑角回、右侧脑楔前叶的f ALFF值均显著减低(均为P<0.05),未发现f ALFF值增高的脑区;右侧脑角回、右侧脑楔前叶的f ALFF值与视网膜神经纤维层厚度均呈负相关(右侧脑角回:r=-0.607,P=0.010;右侧脑楔前叶:r=-0.504,P=0.020),而与C/D值均未见显著相关性(右侧脑角回:r=0.158,P=0.494;右侧脑楔前叶:r=-0.087,P=0.706);右侧脑角回、右侧脑楔前叶的f ALFF值与视野的平均变异值(右侧脑角回:r=0.096,P=0.468;右侧脑楔前叶:r=0.026,P=0.845)和模式标准差值(右侧脑角回:r=0.064,P=0.626;右侧脑楔前叶:r=-0.145,P=0.268)均无显著相关性。结论 NTG患者静息态多个脑区的功能紊乱可能参与NTG的发病,使之成为临床诊断NTG的可能补充手段,亦可作为评估NTG严重性方面的参考指标。

Objective To investigate the changes in brain function and the relationship between resting state fMRI-fractional amplitude of low frequency fluctuation（rsfMRI-fALFF） and optical coherence tomography（OCT）,visual field in normal tension glaucoma（NTG）,and explore the pathophysiological mechanism of NTG.Methods Totally 20 NTG patients（NTG group） and 20 healthy volunteers（normal control group） were selected,and patients in NTG group were matched with volunteers in gender,age,education level,and the right hand.They were examined by rsfMRI and the data were processed by REST software.The two groups were calculated and compared in fractional amplitude of low frequency fluctuation（fALFF）.Finally,the correlation between fALFF and OCT,visual field in NTG group were examined.Results Compared with the control group,the fALFF values of the right angular gyrus and precuneus of the NTG group were significantly decreased（P〈0.05）,and the fALFF values of the NTG group was not increased in the brain regions.The fALFF values of the right angular gyrus and precuneus were significantly negative correlated with RNFL values（Right angular gyrus：r =-0.607,P =0.010;Right precuneus：r =- 0.504,P = 0.020）.There was no significant correlation between fALFF value and C/D（Right angular gyrus：r =0.158,p=0.494;Right precuneus：r =-0.087,P =0.706）,MD（Right angular gyrus：r = 0.096,P = 0.468;Right precuneus：r = 0.026,P =0.845） and PSD value（Right angular gyrus：r =0.064,p =0.626;Right precuneus：r =-0.145,P = 0.268）.Conclusion The disorder of multiple brain regions in NTG patients may be involved in the pathogenesis of NTG.The rsfMRI-fALFF may be the complementary means on the clinical diagnosis of NTG,and can be used as a reference index for assessing the severity of NTG.