title: Ex Vivo Human Placental Perfusion Model for Analysis of Fetal Circulation in the Chorionic Plate.
abstract: OBJECTIVE
  The purpose of this study was to develop an ex vivo placental perfusion model to assess changes in the umbilical artery systolic-to-diastolic (S/D) ratio due to progressive occlusion of the placental arterial system.
  
  
  METHODS
  Ex vivo human placentas were connected to a computerized pulse duplicator mimicking pulsatile flow from the fetal heart. Doppler sonographic measurements were conducted on the umbilical and chorionic arteries of 25 mature placentas. Simulation of placental occlusion was performed by progressive ligature of the chorionic arteries, including one umbilical artery. The correlation between the umbilical artery S/D ratio and the severity of simulated placental occlusion was analyzed.
  
  
  RESULTS
  The normal mean S/D ratio ± SD decreased gradually along the chorionic plate from 2.66 ± 0.47 at the cord insertion to 1.90 ± 0.59 in generation IV of the chorionic vessels. The Doppler index initially increased slowly with simulated placental occlusion. Only when all 4 generations were occluded was the umbilical artery S/D ratio elevated. Complete occlusion of one umbilical artery resulted in a 39% increase in the umbilical artery S/D ratio.
  
  
  CONCLUSIONS
  This unique model combining Doppler sonography with perfusion of an ex vivo placenta can be used for a better understudying of pathologic placental blood flow circulation.
authors.affiliation: Ultrasound Unit in Obstetrics and Gynecology, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel (Z.G., A.J.J.); Department of Obstetrics and Gynecology, Hillel Yaffe Medical Center, Hadera, Israel (L.G.); Department of Biomedical Engineering, Faculty of Engineering (D.E., U.Z.), and Sackler Faculty of Medicine (D.E., A.J.J.), Tel-Aviv University, Tel-Aviv, Israel; and Department of Medical Engineering, Afeka, Tel-Aviv Academic College of Engineering, Tel Aviv, Israel (Z.G.). zoyag@tasmc.health.gov.il.
authors.forename: Zoya
authors.initials: Z
authors.lastname: Gordon
authors.affiliation: Ultrasound Unit in Obstetrics and Gynecology, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel (Z.G., A.J.J.); Department of Obstetrics and Gynecology, Hillel Yaffe Medical Center, Hadera, Israel (L.G.); Department of Biomedical Engineering, Faculty of Engineering (D.E., U.Z.), and Sackler Faculty of Medicine (D.E., A.J.J.), Tel-Aviv University, Tel-Aviv, Israel; and Department of Medical Engineering, Afeka, Tel-Aviv Academic College of Engineering, Tel Aviv, Israel (Z.G.).
authors.forename: Lilia
authors.initials: L
authors.lastname: Glaubach
authors.affiliation: Ultrasound Unit in Obstetrics and Gynecology, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel (Z.G., A.J.J.); Department of Obstetrics and Gynecology, Hillel Yaffe Medical Center, Hadera, Israel (L.G.); Department of Biomedical Engineering, Faculty of Engineering (D.E., U.Z.), and Sackler Faculty of Medicine (D.E., A.J.J.), Tel-Aviv University, Tel-Aviv, Israel; and Department of Medical Engineering, Afeka, Tel-Aviv Academic College of Engineering, Tel Aviv, Israel (Z.G.).
authors.forename: David
authors.initials: D
authors.lastname: Elad
authors.affiliation: Ultrasound Unit in Obstetrics and Gynecology, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel (Z.G., A.J.J.); Department of Obstetrics and Gynecology, Hillel Yaffe Medical Center, Hadera, Israel (L.G.); Department of Biomedical Engineering, Faculty of Engineering (D.E., U.Z.), and Sackler Faculty of Medicine (D.E., A.J.J.), Tel-Aviv University, Tel-Aviv, Israel; and Department of Medical Engineering, Afeka, Tel-Aviv Academic College of Engineering, Tel Aviv, Israel (Z.G.).
authors.forename: Uri
authors.initials: U
authors.lastname: Zaretsky
authors.affiliation: Ultrasound Unit in Obstetrics and Gynecology, Lis Maternity Hospital, Tel-Aviv Sourasky Medical Center, Tel-Aviv, Israel (Z.G., A.J.J.); Department of Obstetrics and Gynecology, Hillel Yaffe Medical Center, Hadera, Israel (L.G.); Department of Biomedical Engineering, Faculty of Engineering (D.E., U.Z.), and Sackler Faculty of Medicine (D.E., A.J.J.), Tel-Aviv University, Tel-Aviv, Israel; and Department of Medical Engineering, Afeka, Tel-Aviv Academic College of Engineering, Tel Aviv, Israel (Z.G.).
authors.forename: Ariel J
authors.initials: AJ
authors.lastname: Jaffa
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology*; D002823:Chorion / Q000098:blood supply / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D009924:Organ Culture Techniques / Q000295:instrumentation* / Q000379:methods*; D010920:Placenta / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology*; D011247:Pregnancy; D018608:Ultrasonography, Doppler / Q000379:methods; D016216:Ultrasonography, Prenatal / Q000379:methods; D014469:Umbilical Arteries / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology*
keywords: Doppler indices; experimental model; gynecologic ultrasound; perfusion; placenta