USMLE Step 1 Question 333

Question:

A 25-year-old woman is undergoing a nephrectomy in order to donate her kidney to her older sister, who has renal failure. The surgeon accidentally cuts a vein draining into the inferior aspect of the renal vein on the side of the kidney which is to be removed.

What is the most likely identity of this vein?

Correct Answer: A.  Left ovarian vein

The left ovarian vein (or testicular vein in men) enters the inferior aspect of the left renal vein.

The left suprarenal vein (B) also enters the left renal vein, but at its superior aspect.

The right ovarian (C) and right suprarenal (D) veins drain directly into the inferior vena cava.

The splenic vein (E) joins with the superior mesenteric vein to form the portal vein.

Of note, in kidney transplantation, the left kidney is usually preferred because the left renal vein is longer than the right renal vein (the left renal vein has to cross over the vertebral column to get to the inferior vena cava while the right does not).