Fig. 2

a B-mode US: longitudinal sub-xyphoid scan of the abdominal aorta at the level of the arising superior mesenteric artery (arrowhead), showing the retro-aortic left renal vein (long arrow) compressed between the abdominal aorta (*) and an osteophyte (short arrow) of the third lumbar vertebral body. b Duplex Doppler US of the left renal artery showing a higher resistive index value (0.76). c Power Doppler US of the pampiniform plexus showing left varicocele (grade IV on Sarteschi’s scale)