OBJECTIVE To determine whether helical computed tomography (CT) performed during intravenous cholangiography can provide useful images of the biliary tree and to compare this technique with endoscopic retrograde cholangiography (ERC). METHODS Eighteen adult patients with clinically suspected biliary disease who were referred for ERC were first examined with helical CT cholangiography performed 75 minutes after intravenous infusion of 100 mL of 10.3% iodipamide meglumine. RESULTS Helical CT cholangiography revealed good opacification of the biliary tree in 13 of 14 patients with serum bilirubin levels less than 2 mg/dL (34 mumol/L) and poor opacification in three of four patients with levels greater than 2 mg/dL. In six of seven patients with choledocholithiasis, the diagnosis was made by means of helical CT cholangiography. CONCLUSIONS Helical CT cholangiography may be a clinically useful method for visualization of the biliary tree in some patients with suspected biliary disease with normal bilirubin levels and in patients in whom attempts at ERC fail.