Role of magnetic resonance diffusion tensor imaging on prognostic evaluation of term neonates with asphyxia / 中华实用儿科临床杂志

ABSTRACT

Objective To discuss the prognostic evaluation of magnetic resonance diffusion tensor imaging (DTI) in term neonates with mild and severe asphyxia.Methods Eleven neonates with mild asphyxia,14 neonates with severe asphyxia and 10 control neonates were studied.All the neonates were examined by conventional magnetic resonance imaging(MRI) and DTI.Fraction anisotropy (FA) values,apparent diffusion coefficient (ADC) values,voxel numbers and fiber numbers were calculated in seven regions of interest(ROI) and compared among the 3 groups.The correlation between FA values and neonatal behavioral neurological assessment (NBNA) scores were analyzed.Results (1) FA values in the left and the right thalamus were 0.54 ± 0.08 and 0.56 ± 0.15 in control group,0.45 ±0.03 and 0.44 ± 0.10 in mild group,and 0.21 ± 0.11 and 0.25 ± 0.13,respectively in severe group.FA values in posterior limbs of internal capsule were 0.49 ± 0.09 and 0.48 ± 0.08 in control group,0.37 ± 0.08 and 0.38 ± 0.03 in mild group,and 0.20 ± 0.04,0.19 ± 0.13 in severe group;FA values in thalamus and posterior limbs of internal capsule had statistical differences among the 3 groups (F =9.12,9.11,8.18,8.55,all P ＜ 0.05).Voxel numbers in the left and the right superior longitudinal fasciculus were 1 094 ± 112 and 1 123 ± 113 in control group,986 ± 111 and 1 009 ± 144 in mild group,450 ± 116 and 671 ± 126 in severe group.Voxel numbers in anterior limbs of internal capsule were 947 ± 104 and 1 237 ± 184 in control group,854 ± 118 and 799 ± 114 in mild group,324 ± 110 and 311 ± 126 in severe group.Voxel numbers in posterior limbs of internal capsule were 2 047 ± 129 and 2 137 ± 238 in control group,1 843 ± 233 and 1 753 ± 247 in mild group,867 ± 118 and 999 ± 167 in severe group.Voxel numbers in superior longitudinal fasciculus,anterior and posterior limbs of internal capsule had statistical differences among the 3 groups (F =10.11,9.45,7.33,8.45,12.65,11.23,all P ＜ 0.05);Fiber numbers in the left and the right cingulate gyrus were 245 ±72 and 405 ±94 in control group,225 ±52 and 365 ± 114 in mild group,145 ±62 and 185 ±84 in severe group.Fiber numbers in inferior front-occipital fasciculus were 56 ± 19 and 212 ± 33 in control group,49 ±22 and 197 ± 33 in mild group,33 ± 12 and 156 ± 39 in severe group.Fiber numbers in posterior limbs of internal capsule were 284 ± 112 and 988 ± 233 in control group,234 ± 67 and 678 ± 234 in mild group,114 ± 67 and 188 ± 84 in severe group.Fiber numbers in cingulate gyrus,inferior front-occipital fasciculus and posterior limbs of internal capsule had statistical differences among the 3 groups (F =3.11,3.45,9.88,9.12,7.45,8.88,all P ＜ 0.05).(2) The correlation between FA value and NBNA scores was analyzedthe correlation coefficient in posterior limbs of internal capsule was 0.666 which was higher than those of the other areas.The area under the ROC curve of FA values in anterior limbs of internal capsule was 0.816 (P =0.005),used NBNA scores ≥ 35 as a good outcome.FA values (≥ 0.375) in the posterior limbs of the internal capsules predicted a good outcome and the corresponding sensitivity and specificity was 73.1％ and 77.8％,respectively.Conclusion In some ROIs,FA values,voxel numbers,and fiber numbers can quantitatively reflect the degree of white matter injury in neonates with asphyxia.Furthermore,the FA values in the posterior limbs of the internal capsules are closely correlated with NBNA scores,so it has more important clinical significance,and can accurately and objectively assess the prognosis in neonates with asphyxia.