**Question:** Surgeon excises a portion of the liver to the left of the attachment of the falciform ligament. The segments that have been resected are:

The falciform ligament is a fibrous structure that connects the liver to the right anterior abdominal wall. When a portion of the liver is resected to the left of this ligament, the segments involved are:

**Core Concept:**
The liver is divided into eight segments based on the division of its vascular and biliary systems. These segments are named according to their dominant blood supply and biliary drainage. The falciform ligament marks the border between segments IV and V of the liver.

**Why the Correct Answer is Right:**
The surgeon excised the liver segments to the left of the falciform ligament, which is the border between segments IV and V. Segment IV receives blood supply from the left hepatic artery and drains into the left hepatic duct, while segment V gets its blood supply from the middle hepatic artery and drains into the right hepatic duct. Therefore, the resected segments are IV and V.

**Why Each Wrong Option is Incorrect:**

A. This option is incorrect because segments IV and V are on the right side of the falciform ligament, not to the left.
B. This option is incorrect because segments IV and V receive supply from different arteries (left hepatic artery and middle hepatic artery, respectively) rather than sharing a common artery.
C. This option is incorrect as segments IV and V are located on the right side of the falciform ligament, not to the left.
D. This option is incorrect because segments IV and V receive bile duct drainage from different ducts (left hepatic duct and right hepatic duct, respectively), not sharing a common duct.

**Clinical Pearl:**
Understanding liver segment anatomy is crucial for surgical interventions involving the liver. The falciform ligament helps differentiate between segments IV and V, ensuring appropriate surgical planning and minimizing complications.