From the Department of Radiology (A.K.S.
Diagn Interv Radiol. 2013 Nov-Dec;19(6):495-500. doi: 10.5152/dir.2013.13106.
We aimed to test the null hypothesis that relative apparent diffusion coefficient (rADC) and relative signal intensity values (rSI(HASTE)) do not change in the evaluation of placental maturation with advancing gestational age.
Fifty-six fetuses with diffusion-weighted magnetic resonance imaging (DW-MRI) data were enrolled in this retrospective study. Fetuses were analyzed in three different gestational age groups: group 1, 18-23 weeks; group 2, 24-28 weeks; and group 3, 29-38 weeks. The rADC (mean ADC/ADC(globe)) and rSI(HASTE) values (mean SI(HASTE)/SI(globe)) were obtained. Two radiologists experienced in fetal MRI who were blinded to the patient information reviewed MRI images independently. Kruskal-Wallis Test was used to compare the rADC and rSI(HASTE) with gestational age groups. The agreement between the two blinded readers was tested using Krippendorff's alpha ratio.
Both placental rADC values and placental rSI(HASTE) values were not significantly different between the gestational age groups (P = 0.688 and P = 0.280, respectively). rADC and rSI(HASTE) measurements were reproducible with a good agreement between the two readers (Krippendorff's alpha ratio was 0.613 and 0.778, respectively).
The rADC and rSI(HASTE) values do not change with advancing gestational age.
我们旨在检验一个零假设，即相对表观扩散系数（rADC）和相对信号强度值（rSI(HASTE)）在评估胎盘成熟度时不会随着胎龄的增加而改变。
本回顾性研究共纳入 56 例接受扩散加权磁共振成像（DW-MRI）检查的胎儿。胎儿被分为三组：18-23 周为第 1 组；24-28 周为第 2 组；29-38 周为第 3 组。测量 rADC（平均 ADC/ADC(globe)) 和 rSI(HASTE) 值（平均 SI(HASTE)/SI(globe)))。两位具有胎儿 MRI 经验的放射科医生对 MRI 图像进行独立评估，他们对患者信息不知情。采用 Kruskal-Wallis 检验比较 rADC 和 rSI(HASTE)与胎龄组之间的关系。采用 Krippendorff's alpha 比检验两位盲法读者之间的一致性。
胎盘 rADC 值和胎盘 rSI(HASTE)值在不同胎龄组之间无显著差异（P = 0.688 和 P = 0.280）。rADC 和 rSI(HASTE)测量具有良好的重复性，两位读者之间的一致性较好（Krippendorff's alpha 比分别为 0.613 和 0.778）。
rADC 和 rSI(HASTE)值不会随着胎龄的增加而改变。
