A 52-year-old man from Delhi presents with jaundice and right upper quadrant pain for 3 weeks. Ultrasound shows a 4 cm solitary hepatocellular carcinoma in the right lobe of the liver. CT angiography confirms no vascular invasion and normal liver function in the remaining parenchyma. The surgeon plans a right hepatectomy. Which hepatic segments will be removed during this procedure?

Explanation

## Hepatic Segmental Anatomy and Right Hepatectomy **Key Point:** The liver is divided into 8 functional segments (I–VIII) based on vascular and biliary supply. Right hepatectomy removes segments V, VI, VII, and VIII. ### Segmental Organization The **Couinaud classification** divides the liver into segments supplied by branches of the hepatic artery, portal vein, and drained by hepatic veins: | **Segment** | **Location** | **Lobe** | **Vascular Supply** | | --- | --- | --- | --- | | I (Caudate) | Posterior, between IVC and lesser omentum | Independent | Hepatic artery & portal vein branches | | II | Left lateral superior | Left lobe | Left branch | | III | Left lateral inferior | Left lobe | Left branch | | IV | Left medial (quadrate lobe) | Left lobe | Left branch | | V | Right anterior inferior | Right lobe | Right anterior branch | | VI | Right posterior inferior | Right lobe | Right posterior branch | | VII | Right posterior superior | Right lobe | Right posterior branch | | VIII | Right anterior superior | Right lobe | Right anterior branch | ### Right Hepatectomy **Right hepatectomy removes:** Segments **V, VI, VII, VIII** - Supplied by the **right hepatic artery** and **right portal vein** - Drained by the **right hepatic vein** - Preserves the **left lobe** (segments II, III, IV) and **segment I** (caudate lobe has independent blood supply) **High-Yield:** Segment I (caudate) is NOT removed in right hepatectomy because it has dual blood supply from both right and left hepatic vessels and drains independently via small hepatic veins directly into the IVC. ### Clinical Significance **Clinical Pearl:** In this case, the tumor is in the right lobe with normal left lobe function, making right hepatectomy appropriate. The remnant liver (left lobe + caudate) provides adequate synthetic function for recovery. ```mermaid flowchart TD A[Liver Segmentation - Couinaud]:::outcome --> B{Right or Left Lobe?}:::decision B -->|Right Lobe| C[Segments V, VI, VII, VIII]:::action B -->|Left Lobe| D[Segments II, III, IV]:::action A --> E[Segment I - Caudate]:::outcome E --> F[Independent vascular supply<br/>Preserved in right hepatectomy]:::action ``` **Mnemonic:** **"Right 5-6-7-8"** — segments V, VI, VII, VIII are removed in right hepatectomy.