Superior Perspective Focused on the Left Anterior Lateral Segment of the Male Liver

Description

Arising beneath the left hemidiaphragm, the left anterior lateral segment of the liver (Couinaud segment III) occupies the superior aspect of the left hepatic lobe, lateral to the falciform ligament and anterior to the left hepatic vein as it courses toward the inferior vena cava. Segment III lies inferior to segment II on the diaphragmatic surface, with its medial border approaching the umbilical fissure and ligamentum teres, and its lateral margin rounding toward the left triangular ligament. From this superior perspective, the parenchymal dome and its gentle convexity toward the diaphragm read clearly. Orientation is straightforward. Segment III matters because it is a common target in left lateral sectionectomy (segments II and III) for hepatocellular carcinoma, colorectal liver metastases, and living donor transplantation, where the left hepatic vein and the umbilical portion of the left portal vein define safe planes for parenchymal transection. Small differences in the superior contour and in the relationship to the falciform ligament can change trocar placement and the line of stapling in laparoscopic approaches. Couinaud segmentation is also the language of radiology reports, so a crisp, isolated view of segment III helps align operative planning with CT or MRI descriptions. Use this illustration in hepatobiliary surgery teaching, transplant anatomy modules, and in surgical atlases explaining left lobe segmental anatomy and resection strategy, as well as in radiology or anatomy coursework that drills Couinaud segment identification on the liver’s diaphragmatic surface. It also fits patient-facing publisher graphics when segment-based localization must stay anatomically correct without excess detail. Anatomical accuracy verified by SciePro's Medical Advisory Board.