Liver segment

The liver segment is a part of the liver, an organ in the human body. The liver is divided into a number of functional units, known as segments. These segments are based on the distribution of the portal vein, hepatic artery, and bile ducts.

Etymology

The term "segment" comes from the Latin word "segmentum", which means "a piece cut off", reflecting the fact that each liver segment can function independently.

Anatomy

The liver is divided into eight segments, each of which is supplied by its own branch of the portal vein, hepatic artery, and bile duct. These segments are numbered in a clockwise direction, starting from the caudate lobe. The segments are as follows:

1. Segment I: Caudate lobe
2. Segment II: Left lateral superior segment
3. Segment III: Left lateral inferior segment
4. Segment IV: Left medial segment
5. Segment V: Right anterior inferior segment
6. Segment VI: Right posterior inferior segment
7. Segment VII: Right posterior superior segment
8. Segment VIII: Right anterior superior segment

Clinical Significance

Understanding the segmentation of the liver is crucial in hepatic surgery and liver transplantation. It allows surgeons to remove diseased segments while preserving healthy ones, thus minimizing the impact on liver function.

Related Terms

• Hepatic lobule
• Hepatic vein
• Hepatic portal system
• Liver transplantation
• Hepatic surgery

See Also

• Liver
• Hepatic artery
• Portal vein
• Bile duct

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  Liver segment
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  Liver segment