Skip to content
EasyAnatomyLab
Menu

Hepatovenous segment IV: anatomy, location and function

Couinaud segment IV is the left medial section of the liver, also called the quadrate lobe in its inferior part. Each Couinaud segment is a functionally independent unit of liver with its own portal triad (portal vein branch, hepatic artery branch, bile duct) and hepatic venous drainage, so it can be resected separately.

Loading 3D model…
Skin0%
Muscles100%

Structures

Loading… Click the model or search.

Highlighted in the model: Hepatovenous segment IV. Click any part to read about it, or switch off “Highlight topic” to see the whole body. 3D data: BodyParts3D, © The Database Center for Life Science, CC BY 4.0; meshes simplified and recoloured. The model is an adult male.

Hepatovenous segment IV at a glance

What it is
Couinaud segment IV is the left medial section of the liver, also called the quadrate lobe in its inferior part.
Location
It lies between the falciform ligament on the left and the middle hepatic vein (Cantlie line) on the right, and is divided into IVa (superior) and IVb (inferior).
Function
Each Couinaud segment is a functionally independent unit of liver with its own portal triad (portal vein branch, hepatic artery branch, bile duct) and hepatic venous drainage, so it can be resected separately.
Body system
Digestive · single, midline structure
FMA ID
FMA15742 (Foundational Model of Anatomy)

Key facts

  • The anatomical quadrate lobe corresponds to segment IVb, between the gallbladder fossa and the fissure for the ligamentum teres.
  • Segment IV is supplied by the left portal vein and left hepatic artery, so it belongs to the functional left liver.
  • Segment IV is part of the anatomical right lobe.

Clinical relevance

Segmental anatomy guides surgical planning for liver resections and localisation of lesions on imaging.

Structures next to the hepatovenous segment iv

The nearest named structures in the 3D model, measured from the centre of each part:

References

  1. Foundational Model of Anatomy: Hepatovenous segment IV (FMA15742). EMBL-EBI Ontology Lookup Service.
  2. OpenStax. Anatomy and Physiology 2e, §23.1 Overview of the Digestive System. Rice University, 2022.
  3. Mitsuhashi N. et al. (2009). BodyParts3D: 3D structure database for anatomical concepts. Nucleic Acids Research 37, D782–D785. Data © The Database Center for Life Science, CC BY 4.0.

Explore the whole body in the interactive 3D human anatomy model, or browse the A–Z list of human structures.