title: An objective measurement to diagnose micrognathia on prenatal ultrasound.
abstract: OBJECTIVE
  We introduce the frontal naso-mental angle as an objective measurement for the prenatal detection of fetal retrognathia. The aim of this study is to present normal values for the frontal naso-mental angle from 18 to 35 weeks gestational age.
  
  
  METHODS
  In 81 patients between gestational ages 18 and 35 weeks the frontal naso-mental angle was measured on a profile view of the foetal face. The values were compared with four cases of proven Pierre Robin syndrome.
  
  
  RESULTS
  The frontal naso-mental angle is not dependent on gestational age, the mean value is 146.74 degrees, standard deviation 2.7 degrees; 5th percentile 142 degrees, 95th percentile 151 degrees. All four cases of Pierre Robin syndrome demonstrated a significantly lower frontal naso-mental angle below the 5th percentile.
  
  
  CONCLUSIONS
  The frontal naso-mental angle represents an objective way to diagnose retrognathia.
authors.affiliation: Department of Obstetrics and Gynaecology Antwerp University Hospital UZA, Edegem, Belgium.
authors.forename: G
authors.initials: G
authors.lastname: Palit
authors.forename: Y
authors.initials: Y
authors.lastname: Jacquemyn
authors.forename: M
authors.initials: M
authors.lastname: Kerremans
mesh_terms: D005260:Female; D005315:Fetal Diseases / Q000000981:diagnostic imaging*; D006801:Humans; D008844:Micrognathism / Q000000981:diagnostic imaging*; D010855:Pierre Robin Syndrome / Q000000981:diagnostic imaging*; D011247:Pregnancy; D012016:Reference Values; D016216:Ultrasonography, Prenatal