title: Comparison between multiplanar and rendering modes in the assessment of fetal atrioventricular valve areas by 3D/4D ultrasonography.
abstract: OBJECTIVE
  To compare the agreement of multiplanar and rendering modes in the assessment fetal atrioventricular valves (mitral and tricuspid) areas by three-dimensional (3D) ultrasonography using the software spatio-temporal image correlation (STIC).
  
  
  METHODS
  We conducted a prospective cross-sectional study with normal pregnant women, with single fetuses, between 18-33 weeks. To measure the areas, we used the plan of four-chamber view. In the case of multiplanar, the plane was rotated on the axis "Z" form the heart to position at 9h. For rendering, the green line (region of interest - ROI) was placed from the atria of the heart perpendicular to the crux. The agreement was assessed by a Bland-Altman (limits of agreement) using the relative difference between the measures: ((rendering mode) - (multiplanar mode)) / (average).
  
  
  RESULTS
  328 fetuses were evaluated. We have not identified the occurrence of systematic error between methods: the average relative difference was 1.62% (-2.07% to 5.32%, confidence interval 95%) in the mitral and 1.77% (- 1.08% to 4.62%) in the tricuspid valve. The limits of agreement between methods were -65.26% to 68.51% for the mitral and -49.91% to 53.45% for the tricuspid.
  
  
  CONCLUSIONS
  There was no systematic error between modes and thus the observed values for the area of fetal atrioventricular valves can be used for comparisons needs to be corrected. However, relatively large variations may be observed when repeating the measurement area by different modes.
authors.affiliation: Division of Fetal Cardiology, Department of Obstetrics, Federal University of São Paulo, São Paulo, SP, Brazil. araujojred@terra.com.br
authors.forename: Edward
authors.initials: E
authors.lastname: Araujo Júnior
authors.forename: Liliam Cristine
authors.initials: LC
authors.lastname: Rolo
authors.forename: Christiane
authors.initials: C
authors.lastname: Simioni
authors.forename: Luciano Marcondes Machado
authors.initials: LM
authors.lastname: Nardozza
authors.forename: Luciane Alves da
authors.initials: LA
authors.lastname: Rocha
authors.forename: Wellington P
authors.initials: WP
authors.lastname: Martins
authors.forename: Antonio Fernandes
authors.initials: AF
authors.lastname: Moron
mesh_terms: D003430:Cross-Sectional Studies; D019560:Echocardiography, Three-Dimensional / Q000379:methods*; D005260:Female; D005333:Fetus; D005865:Gestational Age; D006801:Humans; D007090:Image Interpretation, Computer-Assisted / Q000379:methods; D008943:Mitral Valve / Q000000981:diagnostic imaging*; D011247:Pregnancy; D011446:Prospective Studies; D012016:Reference Values; D015203:Reproducibility of Results; D014261:Tricuspid Valve / Q000000981:diagnostic imaging*; D016216:Ultrasonography, Prenatal / Q000379:methods*