EA fetus 7328 and LUMIERE Platform, Université de Paris, Paris, France; Service de Gynécologie-Obstétrique, CHU Nantes, 38 bd Jean Monnet, 44000, Nantes, France.
EA fetus 7328 and LUMIERE Platform, Université de Paris, Paris, France; Radiology Department, Assistance Publique - Hôpitaux de Paris, Hôpital Necker - Enfants Malades, 149 rue de Sèvres, 75015, Paris, France.
Placenta. 2021 Nov;115:20-26. doi: 10.1016/j.placenta.2021.08.056. Epub 2021 Aug 24.
Ultrasound is widely used as the initial diagnostic imaging modality during pregnancy with both high spatial and temporal resolution. Although MRI in pregnancy has long focused on the fetus, its use in placental imaging has greatly increased over recent years. In addition to the possibilities of evaluating function, MRI with a wide field of view and high contrast resolution allows characterization of placental anatomy, particularly in situations that are difficult to specify with ultrasound, especially for suspected placenta accreta. MRI also appears to be a particularly useful examination for the anatomical evaluation of the placenta independent of maternal body habitus or fetal position. Indeed, surprisingly little attention is paid to the placenta in MRI when the indication for the examination is fetal. Thus, some aspects of the placenta seem to us to be important to be recognized by the radiologist and to be described on the MRI report. In this review, we will describe MRI sequences used for, and common features seen in, imaging of i) the normal placenta, ii) abnormal aspects of the placenta that should be identified on MRI performed for fetal reason, and iii) placental anomalies for which placental MRI may be indicated.
超声在妊娠期间被广泛用作初始诊断成像方式，具有高空间和时间分辨率。虽然磁共振成像（MRI）在妊娠期间长期以来一直专注于胎儿，但近年来其在胎盘成像中的应用大大增加。除了评估功能的可能性外，具有宽视野和高对比度分辨率的 MRI 还允许对胎盘解剖结构进行特征描述，特别是在超声难以明确的情况下，尤其是对于疑似胎盘植入的情况。MRI 似乎也是一种特别有用的检查方法，可在不考虑母体体型或胎儿位置的情况下对胎盘进行解剖学评估。事实上，当检查的指征是胎儿时，MRI 对胎盘的关注很少。因此，我们认为胎盘的某些方面对于放射科医生识别并在 MRI 报告中描述很重要。在这篇综述中，我们将描述用于成像的 MRI 序列和常见特征，包括：i）正常胎盘，ii）因胎儿原因进行 MRI 检查时应识别的胎盘异常表现，以及 iii）可能需要进行胎盘 MRI 的胎盘异常。
