title: Effect of early emptying on quantitation and interpretation of liquid gastric emptying studies of infants and young children.
abstract: This study assesses the effect of emptying that occurs during feeding on quantitation and interpretation of liquid gastric emptying studies of infants and young children.
  
  
  METHODS
  Forty-nine 99mTc-sulfur colloid liquid gastric emptying studies of 44 children (22 boys, 22 girls; mean age, 20 mo; age range, 2-46 mo) fed orally or by gastrostomy tubes were evaluated. Gastric residuals quantitated by 2 commonly used methods, the first of which does not account for early emptying and the second of which does, were compared. With the first method, residual relative to activity in the stomach at the start of imaging (Rg) was quantified by comparing activity in a region of interest (ROI) drawn about the stomach on the final image to activity in an ROI drawn about only the stomach at the start of imaging. With the second method, residual relative to total dose (Rt) was quantified by comparing activity in the same final ROI to activity in an ROI that included stomach and small bowel at the start of imaging. Studies were interpreted independently for Rg and Rt considering a value >70% as evidence of delayed emptying.
  
  
  RESULTS
  Rt was lower than Rg by 15%-16% for the entire population, for patients fed orally, and for patients fed by gastrostomy tube. These differences reached statistical significance (P < 0.0001). In 31 of 49 studies, R1 was lower than Rg by > or =10%. In 8 studies, emptying classified as delayed on the basis of Rg was classified as nondelayed on the basis of Rt. Clinical decisions based on Rt did not require later management changes that would have indicated that treatment of gastric dysmotility had been postponed in any patient.
  
  
  CONCLUSIONS
  Emptying that occurs during feeding should be factored into quantitation of liquid gastric emptying in infants and young children. Not recognizing and accounting for early emptying results in overestimated gastric residuals and can lead to classification of emptying as delayed in children whose residuals of the total administered dose are within a recognized range of normal.
authors.affiliation: Department of Radiology, Children's Hospital, Harvard Medical School, Boston, Massachusetts, USA.
authors.forename: E
authors.initials: E
authors.lastname: Lin
authors.forename: L P
authors.initials: LP
authors.lastname: Connolly
authors.forename: L
authors.initials: L
authors.lastname: Drubach
authors.forename: D
authors.initials: D
authors.lastname: Zurakowski
authors.forename: J
authors.initials: J
authors.lastname: DiCanzio
authors.forename: K
authors.initials: K
authors.lastname: Mitchell
authors.forename: S T
authors.initials: ST
authors.lastname: Treves
mesh_terms: D016022:Case-Control Studies; D004435:Eating; D004750:Enteral Nutrition; D005260:Female; D005746:Gastric Emptying; D005774:Gastrostomy; D006801:Humans; D007223:Infant; D007225:Infant Food; D008297:Male; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D013270:Stomach / Q000000981:diagnostic imaging*; D013671:Technetium Tc 99m Sulfur Colloid; D013997:Time Factors
chemical_list: D019275:Radiopharmaceuticals; D013671:Technetium Tc 99m Sulfur Colloid