Main Model
1 Renal vein
Renal Arteries and Veins
The renal arteries arise at the
level of the intervertebral
(IV) disc between the L1 and L2 vertebrae. The longer right renal artery passes posterior
to the inferior vena cava (IVC). Typically, each artery divides close to the hilum into
five segmental arteries that are end arteries (i.e., they do not
anastomose significantly with other segmental arteries, so that
the area supplied by each segmental artery is an independent,
surgically resectable unit or renal segment). Segmental arteries are distributed to the renal segments as follows:
• The superior (apical) segment is supplied by the superior (apical) segmental artery; the anterosuperior and
antero-inferior segments are supplied by the anterosuperior segmental and antero-inferior segmental arteries; and the inferior segment is supplied by the inferior segmental artery. These arteries originate from the
anterior branch of the renal artery.
• The posterior segmental artery, which originates from
a continuation of the posterior branch of the renal artery,
supplies the posterior segment of the kidney.
Multiple renal arteries are common and usually enter the
hilum of the kidney. Extrahilar renal arteries from
the renal artery or aorta may enter the external surface of the
kidney, commonly at their poles.
Several renal veins drain each kidney and unite in a variable
fashion to form the right and left renal veins; these veins lie
anterior to the right and left renal arteries. The longer left renal
vein receives the left suprarenal vein, the left gonadal (testicular
or ovarian) vein, and a communication with the ascending lumbar
vein; it then traverses the acute angle between the superior mesenteric artery (SMA) anteriorly
and the aorta posteriorly. Each renal vein drains into the inferior vena cava (IVC).