Three-dimensional Power Doppler Ultrasound Study of the Placenta

Advanced ultrasound technology has been a valuable tool in the assessment of placental anatomy and physiology. Con­ ventional two­dimensional (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 three­dimensional (3D) ultra­ sound 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 secondand thirdtrimester 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 hyper­ tension 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.