The importance of understanding the Couinaud nomenclature describing
hepatic segmental anatomy has been increasingly recognized by practicing
radiologists. The normal cholangiographic appearances of the biliary
ductal branches, as well as those of their common anatomic variants, are
less well known. As percutaneous biliary procedures increase in frequency
and complexity, a thorough understanding of this anatomy is of utmost
importance. In this article, we present cholangiograms, computed
tomographic (CT) scans, and anatomic drawings to illustrate
cholangiographic segmental anatomy and its correlation with segmental
anatomy as depicted by CT. The significance of the anatomy to percutaneous
interventional procedures is discussed.