title: Assessment of the optimal temporal window for intravenous CT cholangiography.
abstract: The optimal temporal window of intravenous (IV) computed tomography (CT) cholangiography was prospectively determined. Fifteen volunteers (eight women, seven men; mean age, 38 years) underwent dynamic CT cholangiography. Two unenhanced images were acquired at the porta hepatis. Starting 5 min after initiation of IV contrast infusion (20 ml iodipamide meglumine 52%), 15 pairs of images at 5-min intervals were obtained. Attenuation of the extrahepatic bile duct (EBD) and the liver parenchyma was measured. Two readers graded visualization of the higher-order biliary branches. The first biliary opacification in the EBD occurred between 15 and 25 min (mean, 22.3 min +/- 3.2) after initiation of the contrast agent. Biliary attenuation plateaued between the 35- and the 75-min time points. Maximum hepatic parenchymal enhancement was 18.5 HU +/- 2.7. Twelve subjects demonstrated poor or non-visualization of higher-order biliary branches; three showed good or excellent visualization. Body weight and both biliary attenuation and visualization of the higher-order biliary branches correlated significantly (P<0.05). For peak enhancement of the biliary tree, CT cholangiography should be performed no earlier than 35 min after initiation of IV infusion. For a fixed contrast dose, superior visualization of the biliary system is achieved in subjects with lower body weight.
authors.affiliation: Department of Radiology, Duke University Medical Center, Durham, NC 27710, USA. sebastian.schindera@duke.edu
authors.forename: Sebastian T
authors.initials: ST
authors.lastname: Schindera
authors.forename: Rendon C
authors.initials: RC
authors.lastname: Nelson
authors.forename: Erik K
authors.initials: EK
authors.lastname: Paulson
authors.forename: David M
authors.initials: DM
authors.lastname: DeLong
authors.forename: Elmar M
authors.initials: EM
authors.lastname: Merkle
mesh_terms: D000328:Adult; D002758:Cholangiography / Q000379:methods*; D003287:Contrast Media / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008875:Middle Aged; D013997:Time Factors; D014057:Tomography, X-Ray Computed
chemical_list: D003287:Contrast Media