A 65-year-old male patient with a history of smoking for 20 pack years underwent a AAA screening. He has a history of hypertension for the past 25 years and has been on antihypertensive agents since he was diagnosed. There is no family history of AAA. He has no abdominal or new onset back or groin pain. The following image was obtained at the level of the mid abdominal aorta in the transverse plane.
What vascular structure is the yellow arrow pointing to? (On the left side you can see the actual smaller image and on the right side is the zoomed in image).
B. Left renal artery
C. Superior mesenteric vein
D. Left renal vein
Answer: D, left renal vein.