The segmental description of the liver proposed by Couinaud in 1957 has been widely adopted and is the basis of anatomical segmental liver surgery. The anatomic division of the liver into right and left lobes is the line (Cantlie's) between the inferior vena cava and the gallbladder bed. Couinaud numbered the segments starting from the caudate lobe and proceeding in a counter-clockwise direction from the posterior view. Leonardo da Vinci said "do not trouble yourself with words to describe anatomy unless you are talking to a blind man", so enough said. Study the two series of rotational animations that follow to get a three-dimensional understanding of segmental relationships.
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