title: Comparison of ex-vivo high-resolution episcopic microscopy with in-vivo four-dimensional high-resolution transvaginal sonography of the first-trimester fetal heart.
abstract: OBJECTIVE
  To compare the capability of three-dimensional (3D) reconstructed images produced by high-resolution episcopic microscopy (HREM) with that of in-vivo four-dimensional high-resolution transvaginal sonography (4D-HRTVS) to discern morphological features of the first-trimester human fetal heart.
  
  
  METHODS
  This was a prospective study of fetal hearts between 9 and 14 weeks' gestation. For ex-vivo 3D analysis, 30 human fetal hearts (at 9 + 0 to 14 + 6 weeks) were retrieved from surgical terminations of pregnancy. The specimens were embedded in resin and episcopic ('block-face') imaging was used to obtain a digital volume dataset (HREM) using 3-micron slicing. 4D-HRTVS was performed in 28 separate pregnancies at 10 + 2 to 14 + 0 weeks using a Voluson E8 ultrasound machine with volumetric transvaginal RIC 6-12-MHz transducers. Heart volumes obtained by both methods were compared to assess their ability to demonstrate first-trimester cardiac morphology. Comparisons were made in the transverse and sagittal planes, and using volume rendering.
  
  
  RESULTS
  All hearts were structurally normal, although abdominal situs was not examined in the isolated hearts that underwent HREM. 4D-HRTVS demonstrated each of the complete five transverse cardiac views in 32-86% of cases. HREM showed four features unique to the first-trimester human heart: prominent atrial appendages, spiral ventricular arrangement, prominent coronary arteries and thickened arterial walls. 4D-HRTVS could demonstrate the first two, but ultrasound resolution was too poor to quantify wall thickness and demonstrate coronary arteries in the 3-5-mm diameter heart.
  
  
  CONCLUSIONS
  4D-HRTVS showed limited morphological features of the first-trimester fetal heart compared with HREM. HREM provides a gold standard of ex-vivo imaging against which developments in ultrasound resolution could be compared.
authors.affiliation: Department of Obstetrics and Gynecology, Sheba Medical Center, Tel-Aviv University, Tel Hashomer, Israel. liat@dr-gindes.co.il
authors.forename: L
authors.initials: L
authors.lastname: Gindes
authors.forename: H
authors.initials: H
authors.lastname: Matsui
authors.forename: R
authors.initials: R
authors.lastname: Achiron
authors.forename: T
authors.initials: T
authors.lastname: Mohun
authors.forename: S Y
authors.initials: SY
authors.lastname: Ho
authors.forename: H
authors.initials: H
authors.lastname: Gardiner
mesh_terms: D019561:Echocardiography, Four-Dimensional / Q000379:methods*; D005260:Female; D005318:Fetal Heart / Q000002:abnormalities / Q000033:anatomy & histology / Q000000981:diagnostic imaging*; D006352:Heart Ventricles / Q000002:abnormalities / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008853:Microscopy / Q000379:methods*; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011446:Prospective Studies; D016216:Ultrasonography, Prenatal / Q000379:methods; D014621:Vagina