Department of Pediatric Radiology, Pellegrin Hospital, CHU Bordeaux, Place Amélie Raba-Léon, Bordeaux, France.
Department of Diagnostic and Interventional Oncologic Imaging, Institut Bergonié, Bordeaux, France.
Pediatr Radiol. 2021 Sep;51(10):1826-1838. doi: 10.1007/s00247-021-05064-1. Epub 2021 May 21.
Quantitative magnetic resonance imaging (MRI) could improve the estimation of fetal brain maturation and the interpretation of white matter signal intensity in pathological conditions.
To investigate T2-based and diffusion-weighted imaging (DWI) measurements for the evaluation of fetal brain maturation during the last trimester of pregnancy.
One hundred sixty-eight fetal brain MRIs were retrospectively analyzed (age range: 28-37 weeks of gestation) after ensuring that none of the children developed psychomotor or cognitive impairment (median follow-up: 4.7 years). Bilateral regions of interest were drawn on the frontal, occipital, parietal and temporal lobes from T2-W imaging and DWI, when available, to evaluate signal intensity and apparent diffusion coefficient (ADC) values. Ratios were calculated with two references (pons or thalamus and cerebrospinal fluid) to standardize signal intensities. Reproducibility was evaluated with intraclass correlation coefficients (ICCs) and Bland-Altman plots. Correlations with gestational age were evaluated with univariate and multivariate linear regressions.
T2 measurements were achieved in all cases, and DWI was available in 37 cases. Measurements and ratios were reproducible in eight localizations (i.e. intra- and interobserver ICCs >0.5): frontal T2/thalamus, parietal T2/thalamus, occipital T2/pons, parietal ADC/thalamus, occipital ADC/pons, temporal ADC/pons, occipital ADC and temporal ADC. The frontal T2/thalamus and parietal T2/thalamus correlated with gestational age (P<0.0001 and P=0.014, respectively). In the multivariate modeling, frontal T2/thalamus remained an independent predictor of the gestational age (P<0.0001).
The frontal T2/thalamus ratio emerged as a potential additional biomarker of fetal brain maturation during the last trimester of pregnancy.
定量磁共振成像（MRI）可以提高对胎儿脑成熟度的估计，并有助于对病理条件下的脑白质信号强度进行解读。
探讨 T2 加权成像（T2-WI）和弥散加权成像（DWI）测量在妊娠晚期评估胎儿脑成熟度中的作用。
回顾性分析 168 例胎儿脑 MRI 资料（胎龄 28-37 周，中位数随访时间 4.7 年），所有胎儿均未出现精神运动或认知障碍。在 T2-WI 及 DWI（如有）上双侧勾画感兴趣区，以评估信号强度和表观弥散系数（ADC）值。采用两种参照（脑桥或丘脑、脑脊液）的比值来标准化信号强度。采用组内相关系数（ICC）和 Bland-Altman 图评估重复性。采用单变量和多变量线性回归评估与胎龄的相关性。
所有病例均完成 T2 测量，37 例可获得 DWI。8 个部位（即观察者内和观察者间 ICC>0.5）的测量值和比值具有可重复性：额部 T2/丘脑、顶叶 T2/丘脑、枕部 T2/脑桥、顶叶 ADC/丘脑、枕部 ADC/脑桥、颞叶 ADC/脑桥、枕部 ADC 和颞叶 ADC。额部 T2/丘脑和顶叶 T2/丘脑与胎龄相关（P<0.0001 和 P=0.014）。在多变量建模中，额部 T2/丘脑仍然是胎龄的独立预测因子（P<0.0001）。
在妊娠晚期，额部 T2/丘脑比值可能成为胎儿脑成熟度的潜在附加生物标志物。
