title: Gastric emptying scintigraphy: is four hours necessary?
abstract: BACKGROUND
  Recommendations for gastric emptying scintigraphy (GES) suggest imaging over 4 hours to better define gastroparesis.
  
  
  OBJECTIVE
  To determine the value of defining delayed gastric emptying at time points earlier than 4 hours.
  
  
  METHODS
  GES was performed with ingestion of a liquid egg white meal with imaging at 0, 0.5, 1, 2, 3, and 4 hours. Patients completed the Patient Assessment of Gastrointestinal Symptoms questionnaire immediately before GES.
  
  
  RESULTS
  Of 1499 patients undergoing GES from September 2007 to January 2010 (76.2% were female, mean age of 45.5±0.5 y, 21.3% had diabetes, 9.5% had earlier gastric surgery), 160 (10.7%) had increased gastric retention at 1 hour (>90%), 404 (27%) had increased retention at 2 hours (>60%), 576 (38.4%) had increased retention at 3 hours (>30%), and 629 (42%) had increased retention at 4 hours (>10%). Gastric retention at 4 hours correlated with retention at 3 hours (r=0.890; P<0.001), 2 hours (r=0.738; P<0.001), and 1 hour (r=0.510; P<0.001). Symptoms correlated better with the gastric retention at later time points. The symptoms correlating with gastric retention at 4 hours included early satiety (r=0.170; P<0.01), vomiting (r=0.143; P<0.01), feeling excessively full after meals (r=0.123; P<0.01), and loss of appetite (r=0.122; P<0.01).
  
  
  CONCLUSIONS
  Gastric retention at 4 hours correlates well with gastric retention at 3 hours, good at 2 hours, but only fair with gastric retention at 1 hour. Gastric retention at 1 hour may miss 36% of patients found to have delayed gastric emptying at 4 hours. Symptoms (early satiety, vomiting, feeling excessively full after meals, and loss of appetite) correlated better with the gastric retention at later time points.
authors.affiliation: Department of Medicine, Gastroenterology Section, Temple University School of Medicine, Philadelphia, PA 19140, USA. henry.parkman@temple.edu
authors.forename: Murali
authors.initials: M
authors.lastname: Pathikonda
authors.forename: Priyanka
authors.initials: P
authors.lastname: Sachdeva
authors.forename: Nidhi
authors.initials: N
authors.lastname: Malhotra
authors.forename: Robert S
authors.initials: RS
authors.lastname: Fisher
authors.forename: Alan H
authors.initials: AH
authors.lastname: Maurer
authors.forename: Henry P
authors.initials: HP
authors.lastname: Parkman
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D005746:Gastric Emptying / Q000502:physiology*; D018589:Gastroparesis / Q000000981:diagnostic imaging* / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011877:Radionuclide Imaging; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D013671:Technetium Tc 99m Sulfur Colloid; D013997:Time Factors; D055815:Young Adult
chemical_list: D013671:Technetium Tc 99m Sulfur Colloid