title: Reference ranges of fetal aortic and pulmonary valve diameter derived by STIC from 14 to 40 weeks of gestation.
abstract: OBJECTIVE
  To develop reference ranges of fetal aortic and pulmonary valve diameter derived from volume datasets of spatio-temporal image correlation (STIC).
  
  
  METHODS
  A cross-sectional study was undertaken on low-risk pregnancies with well-established data from 14 to 40 weeks. Volume datasets of STIC were acquired for subsequent off-line analysis. Aortic and pulmonary valve diameters were measured in STIC multiplanar view using 4D-View version 9. Normal Z scores and centile reference ranges were constructed from these measurements against gestational age (GA) and biparietal diameter (BPD) as independent variables, using regression models for both mean and SD.
  
  
  RESULTS
  A total of 606 volume datasets were successfully measured. Normal reference ranges for predicting mean values and SD of aortic and pulmonary valve diameter were constructed based on best-fit equations (linear function) as follows: mean aortic diameter (mm) was modeled as a function of GA (weeks) and BPD (mm) as - 2.4838 + 0.2702 × GA, (SD = 0.1482 + 0.0156 × GA) and - 1.5952 + 0.0989 × BPD (SD = 0.1672 + 0.00572 × BPD). Mean pulmonary diameter was modeled as - 2.5924 + 0.2935 × GA (SD = 0.2317 + 0.01524 × GA) and - 1.6830 + 0.1083 × BPD (SD = 0.1971 + 0.0059 × BPD).
  
  
  CONCLUSIONS
  We have provided nomograms and Z scores of fetal aortic and pulmonary valve diameters. These reference ranges may be a useful tool in the assessment of fetal cardiac abnormalities.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Fuanglada
authors.initials: F
authors.lastname: Tongprasert
authors.forename: Kasemsri
authors.initials: K
authors.lastname: Srisupundit
authors.forename: Suchaya
authors.initials: S
authors.lastname: Luewan
authors.forename: Supatra
authors.initials: S
authors.lastname: Sirichotiyakul
authors.forename: Wirawit
authors.initials: W
authors.lastname: Piyamongkol
authors.forename: Chanane
authors.initials: C
authors.lastname: Wanapirak
authors.forename: Theera
authors.initials: T
authors.lastname: Tongsong
mesh_terms: D000328:Adult; D001021:Aortic Valve / Q000000981:diagnostic imaging / Q000196:embryology*; D003430:Cross-Sectional Studies; D005260:Female; D005333:Fetus / Q000196:embryology*; D005865:Gestational Age; D006801:Humans; D007089:Image Enhancement; D007090:Image Interpretation, Computer-Assisted; D011247:Pregnancy; D011664:Pulmonary Valve / Q000000981:diagnostic imaging / Q000196:embryology*; D012016:Reference Values; D016216:Ultrasonography, Prenatal / Q000379:methods*