Normal and Variant Anatomy of Renal Hilar Structures and its Clinical Significance

Advanced imaging techniques have resulted in increasing use of minimally invasive approaches for nephron sparing surgeries of kidney. Need for precise knowledge of normal and variant anatomy of vascular pedicle of kidney is thus justified. Ample literature is available on the variations in the intrarenal vascular pattern of the kidney, which are seen frequently. But the variation in arrangement of structures at the renal hilum has not gained much interest up till now. One hundred (51 right and 49 left) embalmed kidneys were utilized for the present study. Careful dissection of renal hilar structures was carried out to observe antero-posterior relationship of structures at the hilum of the kidney. In majority (73%), the arrangement was not according to the normal textbook description i.e. renal vein, renal artery and pelvis arranged antero-posteriorly. In 31% anterior division of renal artery was seen in front of renal vein at the hilum, whereas, in 50% cases the pelvis was not the posterior most relation. The variable patterns observed were classified into five types. In cases of renal hilar tumors laparoscopic partial nephrectomy is being done with a limited field of vision. Knowledge of these variations is useful for operating surgeons to identify and individually clamp the hilar structures, which is advantageous over en-bloc clamping.