title: Three-dimensional sonography of placental mesenchymal dysplasia and its differential diagnosis.
abstract: OBJECTIVE
  Placental mesenchymal dysplasia (PMD) is an uncommon vascular anomaly of the placenta characterized by mesenchymal stem villous hyperplasia. Its main sonographic feature is a thickened placenta with hypoechoic areas, and an accurate sonographic diagnosis is challenging. The aim of this study was to report 2 cases of PMD and discuss the differential diagnosis of its sonographic features.
  
  
  METHODS
  Cases of placental masses were studied by 2-dimensional (2D), 3-dimensional (3D), and color Doppler imaging.
  
  
  RESULTS
  In case 1, a thick placenta with multiple hypoechoic areas was noted at 13 weeks' gestation. At 19 weeks, the multicystic area, clearly demarcated from a normal-looking placenta, measured 6.5 x 8.5 cm and enlarged gradually. The patient gave birth to a 625-g female neonate after spontaneous labor at almost 26 weeks' gestation. In case 2, a first sonographic examination at 25 weeks' gestation revealed a thickened placenta with hypoechoic areas and a fetus with a single umbilical artery and a ventricular septal defect. At 27 weeks, the abnormal area of the placenta measured 14.5 x 7.5 cm. At 32 weeks' gestation, a caesarean delivery was performed because of a nonreassuring fetal heart tracing, and a 1415-g female neonate was delivered. Both cases were evaluated by 2D, 3D, and color Doppler imaging, and the pathologic features of both placentas were consistent with PMD.
  
  
  CONCLUSIONS
  Placental mesenchymal dysplasia should be considered in the differential diagnosis of every placental mass, especially in cases of multicystic placental lesion with lack of high-velocity signals inside the lesion, and a normal karyotype.
authors.affiliation: Perinatology Research Branch, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Department of Health and Human Services, Bethesda, Maryland, USA.
authors.forename: Edi
authors.initials: E
authors.lastname: Vaisbuch
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero
authors.forename: Juan Pedro
authors.initials: JP
authors.lastname: Kusanovic
authors.forename: Offer
authors.initials: O
authors.lastname: Erez
authors.forename: Shali
authors.initials: S
authors.lastname: Mazaki-Tovi
authors.forename: Francesca
authors.initials: F
authors.lastname: Gotsch
authors.forename: Chong Jai
authors.initials: CJ
authors.lastname: Kim
authors.forename: Jung-Sun
authors.initials: JS
authors.lastname: Kim
authors.forename: Lami
authors.initials: L
authors.lastname: Yeo
authors.forename: Sonia S
authors.initials: SS
authors.lastname: Hassan
mesh_terms: D000328:Adult; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D008648:Mesoderm / Q000000981:diagnostic imaging*; D010922:Placenta Diseases / Q000000981:diagnostic imaging*; D011247:Pregnancy; D014463:Ultrasonography / Q000379:methods*