Which structure is found between the superior mesenteric artery (SMA) and the abdominal aorta?

The structure located between the superior mesenteric artery (SMA) and the abdominal aorta is the left renal vein. Anatomically, the left renal vein runs from the left kidney and crosses anterior to the abdominal aorta before it drains into the inferior vena cava.

Understanding the spatial relationships between these structures is crucial, particularly in surgical anatomy and during imaging studies. The SMA arises from the abdominal aorta and typically gives off branches that supply the midgut, while the left renal vein's position is such that it runs laterally to the aorta after crossing over it, thereby placing it directly between the SMA and the aorta.

Other structures such as the right renal vein and the inferior mesenteric vein are positioned differently in relation to the SMA and the abdominal aorta, and the gastric vein drains into the portal circulation rather than being associated with these major vascular structures in the same direct anatomical context.