title: Development of the Fetal Vermis: New Biometry Reference Data and Comparison of 3 Diagnostic Modalities-3D Ultrasound, 2D Ultrasound, and MR Imaging.
abstract: Normal biometry of the fetal posterior fossa rules out most major anomalies of the cerebellum and vermis. Our aim was to provide new reference data of the fetal vermis in 4 biometric parameters by using 3 imaging modalities, 2D ultrasound, 3D ultrasound, and MR imaging, and to assess the relation among these modalities.
  
  
  
  A retrospective study was conducted between June 2011 and June 2013. Three different imaging modalities were used to measure vermis biometry: 2D ultrasound, 3D ultrasound, and MR imaging. The vermian parameters evaluated were the maximum superoinferior diameter, maximum anteroposterior diameter, the perimeter, and the surface area. Statistical analysis was performed to calculate centiles for gestational age and to assess the agreement among the 3 imaging modalities.
  
  
  
  The number of fetuses in the study group was 193, 172, and 151 for 2D ultrasound, 3D ultrasound, and MR imaging, respectively. The mean and median gestational ages were 29.1 weeks, 29.5 weeks (range, 21-35 weeks); 28.2 weeks, 29.05 weeks (range, 21-35 weeks); and 32.1 weeks, 32.6 weeks (range, 27-35 weeks) for 2D ultrasound, 3D ultrasound, and MR imaging, respectively. In all 3 modalities, the biometric measurements of the vermis have shown a linear growth with gestational age. For all 4 biometric parameters, the lowest results were those measured by MR imaging, while the highest results were measured by 3D ultrasound. The inter- and intraobserver agreement was excellent for all measures and all imaging modalities. Limits of agreement were considered acceptable for clinical purposes for all parameters, with excellent or substantial agreement defined by the intraclass correlation coefficient.
  
  
  
  Imaging technique-specific reference data should be used for the assessment of the fetal vermis in pregnancy.
authors.affiliation: From the Antenatal Diagnostic Unit (E.K., S.P., R.B., Y.G., R.A.), Department of Obstetrics and Gynecology, Haim Sheba Medical Center, Sackler School of Medicine, Tel Aviv University, Israel.
authors.forename: E
authors.identifier: 0000-0003-4225-7421
authors.initials: E
authors.lastname: Katorza
authors.affiliation: Prenatal Medicine Unit (E.B., S.T., V.M.), Department of Obstetrics and Gynecology, Modena Hospital, Modena, Italy.
authors.forename: E
authors.identifier: 0000-0003-2020-9111
authors.initials: E
authors.lastname: Bertucci
authors.affiliation: From the Antenatal Diagnostic Unit (E.K., S.P., R.B., Y.G., R.A.), Department of Obstetrics and Gynecology, Haim Sheba Medical Center, Sackler School of Medicine, Tel Aviv University, Israel drsharonperlman@gmail.com sharoni5@yahoo.com.
authors.forename: S
authors.identifier: 0000-0002-8023-0679
authors.initials: S
authors.lastname: Perlman
authors.affiliation: Prenatal Medicine Unit (E.B., S.T., V.M.), Department of Obstetrics and Gynecology, Modena Hospital, Modena, Italy.
authors.forename: S
authors.identifier: 0000-0002-7524-8946
authors.initials: S
authors.lastname: Taschini
authors.affiliation: From the Antenatal Diagnostic Unit (E.K., S.P., R.B., Y.G., R.A.), Department of Obstetrics and Gynecology, Haim Sheba Medical Center, Sackler School of Medicine, Tel Aviv University, Israel.
authors.forename: R
authors.identifier: 0000-0003-3203-0717
authors.initials: R
authors.lastname: Ber
authors.affiliation: From the Antenatal Diagnostic Unit (E.K., S.P., R.B., Y.G., R.A.), Department of Obstetrics and Gynecology, Haim Sheba Medical Center, Sackler School of Medicine, Tel Aviv University, Israel.
authors.forename: Y
authors.identifier: 0000-0002-5266-7769
authors.initials: Y
authors.lastname: Gilboa
authors.affiliation: Prenatal Medicine Unit (E.B., S.T., V.M.), Department of Obstetrics and Gynecology, Modena Hospital, Modena, Italy.
authors.forename: V
authors.identifier: 0000-0002-7750-144X
authors.initials: V
authors.lastname: Mazza
authors.affiliation: From the Antenatal Diagnostic Unit (E.K., S.P., R.B., Y.G., R.A.), Department of Obstetrics and Gynecology, Haim Sheba Medical Center, Sackler School of Medicine, Tel Aviv University, Israel.
authors.forename: R
authors.identifier: 0000-0002-8294-3672
authors.initials: R
authors.lastname: Achiron
mesh_terms: D001699:Biometry / Q000379:methods; D065814:Cerebellar Vermis / Q000000981:diagnostic imaging* / Q000196:embryology*; D005260:Female; D005333:Fetus; D005865:Gestational Age; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D059906:Neuroimaging / Q000379:methods*; D011247:Pregnancy; D012016:Reference Values; D012189:Retrospective Studies; D014463:Ultrasonography; D016216:Ultrasonography, Prenatal / Q000379:methods