Anatomy, Abdomen and Pelvis, Renal Artery

The renal arteries are the only vascular supply to the kidneys. They arise from the lateral aspect of the abdominal aorta, typically at the level of the L1/L2 intervertebral disk, immediately inferior to the origin of the superior mesenteric artery. They are approximately 4 cm to 6 cm long, have a diameter of 5 mm to 6 mm, and run in a lateral and posterior course due to the position of the hilum. They run posterior to the renal vein and enter the renal hilum anterior to the renal pelvis. The renal artery also supplies the adrenal gland and ureter on the ipsilateral side.The right renal artery originates from the anterolateral aspect of the aorta and runs in an inferior course behind the inferior vena cava to reach the right kidney, while the left renal artery originates slightly higher and from a more lateral aspect of the aorta, and runs almost horizontally to the left kidney. The renal arteries divide before entering the renal hilum into anterior and posterior divisions, which receive approximately 75% and 25% of the blood, respectively. The anterior division further divides into the upper, middle, lower, and apical segmental arteries while the posterior division forms the posterior segmental artery. Segmental arteries subsequently divide into lobar, interlobar, arcuate, and interlobular arteries before forming the afferent arterioles which feed into the glomerular capillaries.