Accuracy of Prenatal Ultrasound in Evaluating Placental Pathology Using Superb Microvascular Imaging: A Prospective Observation Study

Superb microvascular imaging (SMI) is a new Doppler method that enables the visualization of low-velocity blood flow. The aim of the study described here was to clarify whether SMI can detect prenatal pathological findings in pathologic placentas. In this prospective diagnostic observational study, pregnant women who were admitted to our center for perinatal management were enrolled. Ultrasound examinations to identify placental pathologies using SMI were performed before delivery. After delivery, the placental tissue was clipped for microscopic examination at locations determined under ultrasound guidance. The accuracy of prenatal ultrasound detection of placental pathologies was compared between women who were admitted because of fetal growth restriction (FGR), pre-eclampsia and other indications. The highest accuracy was observed with placental infarction in FGR (positive predictive value = 100%, sensitivity = 89%, area under the curve = 0.945). As a result, it became clear that SMI can accurately detect placental pathologic findings, such as placental infarction and avascular villi. This modality may improve perinatal management in cases of placental dysfunction.