Prakash Adity, Kumar Ishan, Verma Ashish, Shukla Ram C
Department of Radiodiagnosis and Imaging, Institute of Medical Sciences, Banaras Hindu University, Varanasi, Uttar Pradesh, India.
Acta Radiol. 2023 Apr;64(4):1694-1701. doi: 10.1177/02841851221137274. Epub 2022 Nov 13.
Diffusion-weighted imaging (DWI) is feasible in prenatal imaging, and it exhibits better contrast between the placenta and the myometrium compared to T2-weighted (T2W) images.
To compare magnetic resonance imaging (MRI) features of placenta accreta on T2W and DW imaging.
In this retrospective study, 42 pregnant patients who underwent prenatal MRI were included. MRI was performed on a Siemens 1.5-T scanner. T2W and DWI sequences in the axial, sagittal, and/or coronal planes were compiled for review. Two radiologists independently interpreted T2W and DW images for placenta accreta. T2W and DWI scores were calculated based on the presence of features and graded as low, intermediate, and high risk. The association between imaging features and placental invasion on pathology was calculated using chi-square tests. Sensitivity, specificity, and positive and negative predictive values (NPV) were compared between T2W and DWI interpretations. Inter-reader agreement between the two radiologists for T2W and DWI scores was calculated using Cohen's kappa coefficient.
Out of 42 pregnant patients, 10 were pathologically/surgically proven to have placenta accreta. There were no significant differences between T2W and DWI interpretations. Considering a cutoff >6 as positive, the T2W score had higher sensitivity (90% vs. 80%) and NPV (96.9% vs. 94.1%) than the DWI score. The specificity and positive predictive value were 100% for both scores. The inter-reader agreement of T2W score was higher (k = 0.943 vs. 0.882).
T2W and DWI are comparable in diagnosing placenta accreta spectrum. T2W sequences have higher sensitivity, NPV, and inter-reader agreement than DWI.
扩散加权成像（DWI）在产前成像中是可行的，与T2加权（T2W）图像相比，它在胎盘与子宫肌层之间显示出更好的对比度。
比较胎盘植入在T2W和DW成像上的磁共振成像（MRI）特征。
在这项回顾性研究中，纳入了42例行产前MRI检查的孕妇。MRI检查使用西门子1.5-T扫描仪进行。收集轴位、矢状位和/或冠状位的T2W和DWI序列用于分析。两名放射科医生独立解读T2W和DW图像以诊断胎盘植入。根据特征的存在情况计算T2W和DWI评分，并分为低、中、高风险等级。使用卡方检验计算成像特征与病理上胎盘侵入之间的关联。比较T2W和DWI解读之间的敏感性、特异性以及阳性和阴性预测值（NPV）。使用Cohen卡方系数计算两名放射科医生对T2W和DWI评分的阅片者间一致性。
42例孕妇中，10例经病理/手术证实为胎盘植入。T2W和DWI解读之间无显著差异。将截断值>6视为阳性时，T2W评分的敏感性（90%对80%）和NPV（96.9%对94.1%）高于DWI评分。两种评分的特异性和阳性预测值均为100%。T2W评分的阅片者间一致性更高（k = 0.943对0.882）。
T2W和DWI在诊断胎盘植入谱系方面具有可比性。T2W序列在敏感性、NPV和阅片者间一致性方面高于DWI。
