title: Could a single standardized ultrasonographic measurement of antral area be of interest for assessing gastric contents? A preliminary report.
abstract: OBJECTIVE
  The aim of this preliminary study performed on volunteers was to assess whether a standardized ultrasonographic measurement of the gastric antral cross-sectional area in a single section of the stomach could discriminate between gastric contents after 12 h fasting (fasting stomach) and gastric contents 2 h after ingestion of nonclear liquids or a solid meal.
  
  
  METHODS
  In this crossover study, ultrasonographic measurements of the antral area were performed in the morning in healthy volunteers in three situations in randomized order: after 12 h fasting, 2 h after a solid meal of 300 kcal and 2 h after ingestion of 200 ml of nonclear liquids. These measurements were performed by a physician blinded to the volunteers' status, according to a standardized method, using the abdominal aorta and the left lobe of the liver as internal landmarks. Antral areas were compared among the three sessions, and performance of the test was assessed by plotting receiver operating characteristic curves and calculating the area under the receiver operating characteristic curves for the diagnosis of fasting gastric contents.
  
  
  RESULTS
  Twenty-two volunteers were included, and 65 measures were performed. Antral area was significantly smaller in fasting than in postprandial sessions. The receiver operating characteristic curves showed an excellent performance of ultrasonographic measurement of antral area for discriminating gastric contents in fasting session from gastric contents in nonfasting sessions.
  
  
  CONCLUSIONS
  Results of this preliminary study should be corroborated in further trials. However, one can suppose that ultrasonographic measurement of the antral cross-section area could be of interest for the diagnosis of preoperative gastric vacuity.
authors.affiliation: Université de Lyon, Claude Bernard Lyon 1, France. lionel.bouvet@chu-lyon.fr
authors.forename: Lionel
authors.initials: L
authors.lastname: Bouvet
authors.forename: Anne
authors.initials: A
authors.lastname: Miquel
authors.forename: Dominique
authors.initials: D
authors.lastname: Chassard
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Boselli
authors.forename: Bernard
authors.initials: B
authors.lastname: Allaouchiche
authors.forename: Dan
authors.initials: D
authors.lastname: Benhamou
mesh_terms: D000328:Adult; D000465:Algorithms; D018592:Cross-Over Studies; D005215:Fasting; D005260:Female; D005746:Gastric Emptying; D005766:Gastrointestinal Contents; D006801:Humans; D008297:Male; D008875:Middle Aged; D011706:Pyloric Antrum / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D016037:Single-Blind Method; D013997:Time Factors; D014463:Ultrasonography