title: Fetal aortic arch measurements at 14 to 40 weeks' gestation derived by spatiotemporal image correlation volume data sets.
abstract: OBJECTIVE
  The purpose of this study was to establish reference ranges for the transverse aortic arch diameter (TAD) and distal aortic isthmus diameter (DAID) in normal singleton pregnancies (14-40 weeks) based on the 3-vessel/trachea (3VT) view of cardio-spatiotemporal image correlation (STIC) volume data sets.
  
  
  METHODS
  A prospective descriptive study was conducted on uncomplicated singleton pregnancies with healthy fetuses and an accurate gestational age (GA). Cardio-STIC examinations were performed by experienced sonographers using a high-resolution ultrasound machine, and the volume data sets were manipulated to obtain the 3VT view and measured for the TAD and DAID.
  
  
  RESULTS
  A total of 554 measurements were performed, ranging from 13 to 30 for each gestational week. The best regression models were as follows: TAD (in millimeters) = -1.01 + 1.69 (GA, in weeks) (r(2) = 0.93; P < .001), and DAID (in millimeters) = -0.85 + 1.54 (GA, in weeks) (r(2) = 0.92; P < .001). A table of nomograms for 5th, 50th, and 95th percentile ranges was constructed.
  
  
  CONCLUSIONS
  Normative data for the TAD and DAID at each gestational week from 14 to 40 weeks were constructed by a new technique of measurement based on cardio-STIC. These reference ranges may be useful tools for assessment of fetal aortic arch abnormalities.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand.
authors.forename: Piyarat
authors.initials: P
authors.lastname: Udomwan
authors.forename: Suchaya
authors.initials: S
authors.lastname: Luewan
authors.forename: Theera
authors.initials: T
authors.lastname: Tongsong
mesh_terms: D001013:Aorta, Thoracic / Q000000981:diagnostic imaging* / Q000196:embryology*; D005260:Female; D005865:Gestational Age; D006801:Humans; D007089:Image Enhancement / Q000379:methods; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D021621:Imaging, Three-Dimensional / Q000379:methods*; D009929:Organ Size; D011247:Pregnancy; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016216:Ultrasonography, Prenatal / Q000379:methods*