Three-dimensional power Doppler ultrasound study of the placenta

Abstract

Advanced ultrasound technology has been a valuable tool in the assessment of placental anatomy and physiology. Conventional two-dimensional (2D) sonography reveals placental morphological characteristics, 2D color Doppler can assess blood flow in the placenta, 2D power Doppler can evaluate placental vascular trees, and three-dimensional (3D) ultrasound gives more detailed information on the surface anatomy. Recent advances, such as 3D power Doppler with virtual organ computer aidedanalysis (VOCAL) and histogram analysis can measure the placental volume, and assess utero placental and fetoplacental perfusions. In particular, ‘placental vascular sonobiopsy’ can specifically evaluate the second- and third-trimester placental blood flow and vascularity by obtaining several spherical samples from the placenta that will represent the entire placenta. This article presents normal placental development and pathological findings of the placenta using 3D power Doppler ultrasound, and discusses 3D power Doppler assessments of placental perfusion in highrisk preg nancies, such as fetal growth restriction, pregnancyinduced hypertension and preeclampsia, and, from this basis, reestab lishes the importance of 3D power Doppler ultrasound as a screening, diagnostic, and surveillance tool in normal and abnormal pregnancies.