On an axial CT scan of the abdomen at the level of L1, the structure that lies anterior to the inferior vena cava and to the right of the aorta is the:
- A Head of the pancreas (with the common bile duct running in a groove posteriorly) ✓
- B Right renal artery
- C Portal vein
- D Superior mesenteric artery
Correct answer: A. Head of the pancreas (with the common bile duct running in a groove posteriorly)
Explanation
At the level of L1 (transpyloric plane), the head of the pancreas lies in the C-curve of the duodenum, anterior to the IVC and to the right of the aorta and superior mesenteric vessels. The common bile duct runs in a groove in (or through) the posterior surface of the pancreatic head to reach the duodenum at the ampulla of Vater. This anatomical relationship explains why carcinoma of the pancreatic head causes obstructive jaundice by compressing the common bile duct ('double duct sign' on imaging).
Reference: BD Chaurasia's Human Anatomy, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.