Unilateral left four renal arteries: case report using MDCT angiography.

We report a very rare case of a 57-year-old male who presented four left renal arteries (RAs) [one main RA and three additional renal arteries (AdRAs)] highlighted incidentally on multidetector computed tomography (MDCT) angiography, which was used to investigate the vascular system of the lower limbs. The distance between the extreme points of RAs origin (upper and lower points of origin) from abdominal aorta (AA) was in the left part of 9.83 cm. The distance between the extreme points of penetration (upper and lower points of penetration) into the left renal parenchyma was 5.23 cm. At the level of origin, the main left RA has an endoluminal diameter of 0.63 cm, much larger in comparison to the other additional left RAs (0.43 cm, 0.33 cm and 0.28 cm, respectively). The length of the main left RA was 2.16 cm, significantly shorter in comparison with the other additional left RAs (2.21 cm, 4.26 cm and 4.73 cm, respectively). The second left RA was the main RA; the first left RA was AdRA (polar superior RA); the third left RA was AdRA (hilar RA); the fourth RA was AdRA (polar inferior RA). Knowledge of this anatomical variation should be considered in planning and performing renal vessel surgery, and kidney transplantation.