摘要
目的:探讨DTI联合DKI参数在评估孤独症谱系障碍(ASD)学龄前期儿童大脑异常方面的应用价值.方法:前瞻性将2020年9月—2022年10月在本院诊治的35例2～5岁ASD儿童(ASD组)及20例年龄、性别相匹配的健康儿童(对照组)纳入本研究.所有被试采用GE 3.0T MR机进行颅脑MRI扫描,扫描序列包括常规MRI序列(T1 WI、T2WI、T2-FLAIR)及DKI序列(b=0、1000、2000 s/mm2,25个方向).使用Gesell发育量表评估所有受试者5个能区的发育商,包括适应性行为、大运动、精细动作、语言和个人社交行为.DKI数据经后处理得到轴向扩散系数(AD)、径向扩散系数(RD)和平均扩散峰度(MK).选取双侧额叶白质、顶叶白质、内囊前肢、内囊后肢、尾状核头、壳核、苍白球、丘脑及胼胝体膝部、胼胝体压部作为ROI进行DTI和DKI定量参数的测量.比较两组间大脑各脑区DTI和DKI参数值的差异,分析ASD儿童大脑有显著改变的参数与5项发育商的相关性,利用ROC曲线分析有差异的参数对于ASD的诊断效能.结果:与正常对照组相比,ASD组多个脑区的径向弥散系数(RD)值降低,包括左侧额叶白质(P=0.001)、右侧顶叶白质(P=0.015)、左侧顶叶白质(P=0.011)、左侧尾状核头(P=0.003)、右侧壳核(P=0.008)、左侧丘脑(P=0.010);ASD组左侧苍白球的平均扩散峰度(MK)值升高(P=0.011);两组之间各脑区的轴向扩散系数(AD)值均无显著差异(P＞0.05).ASD组中,右侧顶叶白质和左侧丘脑的RD与适应性行为发育商分别呈负相关和正相关(P=0.029,r=-0.369;P=0.034,r=0.359),右侧顶叶白质的RD与大运动发育商呈负相关(P=0.020,r=-0.390),左侧苍白球的MK与精细动作发育商呈负相关(P=0.027,r=-0.373).ROC曲线显示左侧丘脑RD和左侧苍白球MK对于学龄前期儿童ASD的诊断价值较高,其AUC分别为0.704(P=0.005)和0.723(P=0.003),两者联合诊断时的AUC为0.823(P＜0.001).结论:DTI和DKI定量参数可反映ASD儿童大脑微观结构的改变,对学龄前期ASD儿童具有一定的辅助诊断价值.
Abstract
Objective:The purpose of this study was to explore the value of diffusion tensor ima-ging(DTI)parameters combined with diffusion kurtosis imaging(DKI)parameters in assessing brain abnormalities in preschool-aged children with autism spectrum disorder(ASD).Methods:From Sep-tember 2020 to October 2022,35 aged 2～5 years children with ASD(ASD group)and 20 healthy age-and gender-matched children(control group)were prospectively included in this study.All subjects underwent cranial MRI scan at a GE 3.0T MR scanner,the scanning sequences included conventional sequences(T1WI,T2WI and T2-FLAIR)and DKI sequence(b=0,1000 and 2000s/mm2,25 direc-tions).Gesell Developmental Scale(GDS)was used to assess the developmental quotients of all sub-jects in five domains,including adaptive behavior,gross motor,fine motor,language,and personal so-cial behavior.The axial diffusivity(AD),radial diffusivity(RD)and mean kurtosis(MK)were ob-tained after post-processing of DKI data.Bilateral frontal white matter,parietal white matter,anterior limb of internal capsule,posterior limb of internal capsule,head of caudate nucleus,putamen,globus pallidus,thalamus,genu of corpus callosum and splenium of corpus callosum were selected as brain re-gions for analysis.The differences of DTI and DKI parameters in each brain region between the two groups were compared,and the correlation between the parameters with significant changes in the brain of children with ASD and the five developmental quotients was analyzed.The ROC curve was used to analyze the diagnostic efficacy of different parameters for ASD.Results:Compared with the normal control group,the radial diffusivity(RD)value was reduced in several brain regions in the ASD group,including the left frontal white matter(P=0.001),the right parietal white matter(P=0.015),the left parietal white matter(P=0.011),the left head of caudate nucleus(P=0.003),the right putamen(P=0.008),and the left thalamus(P=0.010);mean kurtosis(MK)value was eleva-ted in the left globus pallidus(P=0.011);there was no significant difference in the axial diffusivity(AD)values between the two groups(all P＞0.05).In the ASD group,RD values of the right parietal white matter and left thalamus were negatively and positively correlated with the adaptive behavioral development quotient(P=0.029,r=-0.369;P=0.034,r=0.359),respectively;and RD values of the right parietal white matter were negatively correlated with the gross motor development quotient(P=0.020,r=-0.390);and MK values of the left pale globe were negatively correlated with the fine motor development quotient(P=0.027,r=-0.373).The ROC curve showed that RD of left thalamus and MK of left globus pallidus had higher diagnostic value for ASD in preschool children,with AUC of 0.704(P=0.005)and 0.723(P=0.003),respectively.The AUC of the combined model with the two parameters above mentioned for diagnosis of ASD was 0.823(P＜0.001).Conclusion:The quantitative parameters of DTI and DKI can reflect the changes of brain microstructure in preschool children with ASD,and have certain auxiliary diagnostic value for preschool children with ASD.
维普
万方数据