title: Corn oil emulsion: a simple cholecystagogue for diagnosis of chronic acalculous cholecystitis.
abstract: This study investigated the use of a corn oil emulsion as an inexpensive alternative to sincalide in the scintigraphic diagnosis of chronic acalculous cholecystitis (CAC).
  
  
  METHODS
  Thirty patients with abdominal or right upper quadrant pain underwent (99m)Tc-disofenin hepatobiliary imaging for 60 min. After gallbladder filling, 30 mL of corn oil emulsion were administered orally to all patients followed by dynamic imaging for an additional 60 min in all patients and for 90 min in 26 patients. Gallbladder emptying kinetics were determined with gallbladder ejection fractions calculated at 30, 60, and 90 min. The results were compared with histopathologic or clinical follow-up data.
  
  
  RESULTS
  Corn oil emulsion was found to be palatable and free of side effects in all patients. Seven of the 30 patients had histopathologic evidence of CAC, whereas the remaining 23 did not have evidence of gallbladder disease based on clinical follow-up. The 30-, 60-, and 90-min gallbladder ejection fractions were determined to be 25% +/- 22% (mean +/- SD), 47% +/- 28%, and 62% +/- 29%, respectively. Receiver-operating-characteristic analysis showed that the 60-min gallbladder ejection fraction best distinguished between CAC and non-gallbladder disease with an area under the curve of 0.963. A 60-min gallbladder ejection fraction of < or = 20% had 100% sensitivity, 96% specificity, 88% positive predictive value, 100% negative predictive value, and 97% overall accuracy for the diagnosis of CAC.
  
  
  CONCLUSIONS
  Standardized corn oil emulsion appears to be an adequate and well-tolerated gallbladder stimulant. Based on receiver-operating-characteristic analysis, a 60-min gallbladder ejection fraction of < or = 20% using this simple cholecystagogue results in high diagnostic accuracy for CAC.
authors.affiliation: Division of Nuclear Medicine, Department of Radiology, University of Iowa Hospitals and Clinics, 200 Hawkins Dr., Iowa City, IA 52242, USA.
authors.forename: Twyla B
authors.initials: TB
authors.lastname: Bartel
authors.forename: Malik E
authors.initials: ME
authors.lastname: Juweid
authors.forename: James A
authors.initials: JA
authors.lastname: Ponto
authors.forename: Michael M
authors.initials: MM
authors.lastname: Graham
mesh_terms: D042101:Acalculous Cholecystitis / Q000000981:diagnostic imaging*; D000293:Adolescent; D000328:Adult; D002648:Child; D002756:Cholagogues and Choleretics; D002908:Chronic Disease; D003314:Corn Oil; D004655:Emulsions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011865:Radioisotope Dilution Technique; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D019785:Technetium Tc 99m Disofenin
chemical_list: D002756:Cholagogues and Choleretics; D004655:Emulsions; D019275:Radiopharmaceuticals; D003314:Corn Oil; D019785:Technetium Tc 99m Disofenin