title: Nonvisualization of the fetal gallbladder: frequency and prognostic importance.
abstract: OBJECTIVE
  To assess the frequency of fetal gallbladder visualization through gestation and to determine the prognostic importance of nonvisualization.
  
  
  METHODS
  Demonstration of the gallbladder was prospectively attempted in 578 consecutive second- and third-trimester obstetric ultrasound examinations. Data regarding gallbladder visualization were stratified into subgroups on the basis of estimated gestational age. Postnatal follow-up was performed in 80 fetuses with nonvisualization of the gallbladder.
  
  
  RESULTS
  The gallbladder was seen on 477 of 578 (82.5%) fetal sonograms. The likelihood of gallbladder visualization increased with advancing gestational age, reaching a plateau of approximately 95% between 24 and 32 weeks. After 32 weeks, the frequency of visualization declined. Seventy-five of the 80 fetuses with nonvisualized gallbladders who underwent follow-up had normal outcomes. Except for one fetus with trisomy 21, all fetuses with abnormalities had relatively minor, non-life threatening problems that did not involve the gallbladder or biliary tract.
  
  
  CONCLUSIONS
  Most fetuses with nonvisualization of the gallbladder have normal outcomes. The rate of nonvisualization of the fetal gallbladder is sufficiently high to undermine the utility of gallbladder visualization as a screen for fetal abnormality.
authors.affiliation: Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA.
authors.forename: B S
authors.initials: BS
authors.lastname: Hertzberg
authors.forename: M A
authors.initials: MA
authors.lastname: Kliewer
authors.forename: C
authors.initials: C
authors.lastname: Maynor
authors.forename: P J
authors.initials: PJ
authors.lastname: McNally
authors.forename: J D
authors.initials: JD
authors.lastname: Bowie
authors.forename: H H
authors.initials: HH
authors.lastname: Kay
authors.forename: M L
authors.initials: ML
authors.lastname: Hage
authors.forename: E
authors.initials: E
authors.lastname: Livingston
mesh_terms: D005260:Female; D005500:Follow-Up Studies; D005704:Gallbladder / Q000002:abnormalities / Q000000981:diagnostic imaging*; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D011256:Pregnancy Outcome; D011379:Prognosis; D011446:Prospective Studies; D016216:Ultrasonography, Prenatal / Q000295:instrumentation / Q000379:methods / Q000706:statistics & numerical data