title: Reproducibility of the study of placental vascularization by three-dimensional power Doppler.
abstract: OBJECTIVE
  To assess the reproducibility of 3D power Doppler study of placental vascularization in order to establish its methodological bases for its further application in normal and pathological pregnancies.
  
  
  METHODS
  A prospective study was carried on 30 normal singleton pregnancies from 14 to 40 weeks. To evaluate placental vascularization 3D power Doppler was applied to obtain a "placental biopsy". The spherical volume acquired was analyzed using the VOCAL imaging program. Two consecutive measurements were taken from each patient by a single observer, obtaining a total of 60 datasets. Placental volume (PV), Mean Gray (MG), Vascularization Index (VI), Flow Index (FI) and Vascularization Flow Index (VFI) were calculated. Intra-class correlation coefficient (ICC) and intra-observer agreement was evaluated.
  
  
  RESULTS
  PV and MG presented an ICC of 0.98 and 0.94 respectively, with differences approaching zero. All 3D power Doppler vascular indices (VI, FI and VFI) showed a correlation greater than 0.85, with a better intra-observer agreement for the flow indices (FI and VFI).
  
  
  CONCLUSIONS
  Placental vascular biopsy through 3D power Doppler is a new and simple tool to routinely study placental vascularization in human pregnancy. Our results provide the validation of the technique demonstrating a good reproducibility of the 3D power Doppler parameters when applied to the study of the placental vascular tree in normal pregnancies.
authors.affiliation: Department of Obstetrics and Gynecology, International Ruber Hospital, Madrid, Spain. ltmerce@meditex.es
authors.forename: Luis T
authors.initials: LT
authors.lastname: Mercé
authors.forename: María J
authors.initials: MJ
authors.lastname: Barco
authors.forename: Santiago
authors.initials: S
authors.lastname: Bau
mesh_terms: D000328:Adult; D001158:Arteries / Q000000981:diagnostic imaging / Q000502:physiology*; D001783:Blood Flow Velocity; D005260:Female; D005865:Gestational Age; D006801:Humans; D010920:Placenta / Q000098:blood supply* / Q000000981:diagnostic imaging; D011237:Predictive Value of Tests; D011247:Pregnancy; D011262:Pregnancy Trimester, Second / Q000502:physiology; D011263:Pregnancy Trimester, Third / Q000502:physiology; D011446:Prospective Studies; D011673:Pulsatile Flow; D012016:Reference Values; D015203:Reproducibility of Results; D018608:Ultrasonography, Doppler; D016216:Ultrasonography, Prenatal