"The renal arteries are a pair of lateral branches arising from the abdominal aorta below the level of superior mesenteric artery at the upper lumbar level (L1-L3). Each renal artery divides into anterior and posterior divisions at or very close to the hilum of the kidney.
Further it divides into segmental arteries to supply the respective segments of the kidney being themselves the end arteries. Renal artery variations are divided into 2 groups: early division and ERA (Extra Renal Arteries). The branching of the main renal artery into segmental branches more proximally than the renal hilus level is called early division. ERA are divided into 2 groups: hilar (accessory) and polar (aberrant) arteries. Hilar arteries enter kidneys from the hilum with the main renal artery, whereas polar arteries enter kidneys directly from the capsule outside the hilum. Conventional textbooks of anatomy define the order of hilar structures from above downwards and from anterior to posterior as renal vein, renal artery and pelvis. Normally, each kidney receives one renal artery. The venous drainage of each kidney is through one renal vein, which drains the blood from
the kidney into the inferior vena cava. The left renal vein also receives left suprarenal and left gonadal veins, in addition to the vein coming out from the kidney. Variations in number, source and course of the renal arteries are common. Knowledge of the variations of renal vascular anatomy has importance in exploration and treatment of renal trauma, renal transplantation, renal artery embolization, surgery for abdominal aortic aneurysm and conservative or radical renal surgery. (Anterpreet K Arora, Poonam Verma, Monika Lalit, Anupama Mahajan and Maneesha Sharma- Variant Segmental Renal Arteries in The Right Kidney- Clinical Correlations-A Case Report)."
Last date updated on June, 2014