Organ
Caudate and quadrate lobes
Surface lobes that map differently onto functional segments
High-yield
The quadrate surface corresponds chiefly to segment IVb of the functional left liver. The caudate is segment I, a separate functional region with variable inflow from both sides.
Overview
On the liver's visceral surface, the porta hepatis separates the caudate region posteriorly from the quadrate region anteriorly. The caudate lies beside the inferior vena cava and ligamentum venosum; the quadrate lies between the gallbladder fossa and the round-ligament fissure. Surface naming should be distinguished from portal segmentation.
Reference facts
- Location
- The caudate is posterior/superior to the porta hepatis; the quadrate is on its anterior/inferior side.
- Parts
- Caudate region: segment I, including caudate process and related portions. Quadrate surface: chiefly the inferior part of segment IV.
- Blood supply
- Caudate portal and arterial branches may arise from right and left systems; the quadrate territory is supplied within the functional left-liver pattern.
- Innervation
- Autonomic fibers reach both through the hepatic plexus.
- Venous/Lymphatic drainage
- Caudate short hepatic veins enter the vena cava, with variable connections to major hepatic veins; segment IV commonly drains toward middle/left hepatic venous channels.
- Relations
- Caudate tissue borders the caval groove and roofs the epiploic foramen; the quadrate is near the gastric outlet and proximal duodenum.
- Function
- Perform hepatic metabolic, synthetic and biliary functions; segmental inflow and outflow explain their differing responses to vascular obstruction.
Clinical correlation
Short caudate veins can provide outflow directly to the inferior vena cava when major hepatic veins are obstructed. Relative preservation and enlargement of the caudate may occur in Budd–Chiari syndrome, but the appearance is not universal.
Frequently asked questions
Where are the caudate and quadrate lobes located?
The caudate is posterior/superior to the porta hepatis; the quadrate is on its anterior/inferior side.
What do the caudate and quadrate lobes do?
Perform hepatic metabolic, synthetic and biliary functions; segmental inflow and outflow explain their differing responses to vascular obstruction.
What are the parts of the caudate and quadrate lobes?
Caudate region: segment I, including caudate process and related portions. Quadrate surface: chiefly the inferior part of segment IV.
What is the blood supply of the caudate and quadrate lobes?
Caudate portal and arterial branches may arise from right and left systems; the quadrate territory is supplied within the functional left-liver pattern.