Which structure is located posterior to the superior mesenteric vein and anterior to the aorta?

• A. Uncinate process
• B. Head of pancreas
• C. Neck of pancreas
• D. Tail of pancreas

Answer: (A)

The uncinate process has a distinctive relationship with major abdominal vessels: it extends posterior to the superior mesenteric vessels (behind the SMV/SMA) and lies anterior to the aorta. This positioning occurs because the ventral pancreatic bud forms this hook-like part that migrates behind the SMA/SMV as the pancreas develops, placing it between those vessels and the aorta. That exact arrangement—posterior to the SMV and anterior to the aorta—is why the uncinate process is the correct structure. The head sits in the duodenum and isn’t defined by being behind the SMV and in front of the aorta; the neck and tail have different relationships with the vessels and with the spleen, not this particular configuration.