title: Is same-day sonography of the gallbladder feasible after intravenous urography or contrast-enhanced computed tomography?
abstract: OBJECTIVE
  To determine whether same-day sonographic evaluation of the gallbladder is possible after the use of oral or intravenous iodinated contrast agents during intravenous urography or computed tomography.
  
  
  METHODS
  One hundred fifty-three patients involved in this prospective study received low-osmolar or conventional contrast material. Each preparation contained 300 mg/mL iodine. Sixty-six patients received contrast agents intravenously, and 87 received them orally. Gallbladder volume was estimated sonographically, and the precontrast volume was used to calculate the volume after contraction at 30-minute intervals up to 2 hours after contrast agent administration.
  
  
  RESULTS
  Gallbladder volume returned to precontrast values at 2 hours irrespective of the type of contrast agent or route of administration. The mean volume after contraction at 0.5 hour was 71% after intravenous contrast agent administration and 76% after oral contrast agent administration. Both changes were statistically significantly different from precontrast values (P < .01, null hypothesis) and were unaffected by the osmolarity of the contrast agent.
  
  
  CONCLUSIONS
  Gallbladder volume was restored to precontrast values 2 hours after contrast agent administration. Thus any strategy involving simultaneous same-day sonographic or computed tomographic assessment of the gallbladder after contrast agent administration can be confidently undertaken after this period. This finding may have cost-saving implications.
authors.affiliation: Unit of Radiology, University of the West Indies, St Augustine, Trinidad.
authors.forename: Omar
authors.initials: O
authors.lastname: Khan
authors.forename: Rene
authors.initials: R
authors.lastname: Naipaul
authors.forename: Paramanand
authors.initials: P
authors.lastname: Maharaj
mesh_terms: D000328:Adult; D003287:Contrast Media; D003974:Diatrizoate Meglumine; D005240:Feasibility Studies; D005260:Female; D005704:Gallbladder / Q000000981:diagnostic imaging*; D016473:Gallbladder Emptying; D006801:Humans; D007472:Iohexol / Q000031:analogs & derivatives*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011856:Radiographic Image Enhancement; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014463:Ultrasonography; D014567:Urography
chemical_list: D003287:Contrast Media; D003974:Diatrizoate Meglumine; D007472:Iohexol; C038192:iopromide