Imaging technology with its advancement in the field of urology is the boon for the patients who require minimally invasive approaches for various kidney disorders. These approaches require a precise knowledge of the normal and variant anatomy of vascular structures at the hilum of the kidney in terms of their pattern of arrangement and division. The present paper describes a bilateral anomalous arrangement of the structures at the renal hilum as well as their peculiar branching pattern which is of clinical and surgical relevance. Multiple branching of the renal vessels was observed in both kidneys due to which the hila were congested. The right renal artery immediately after its origin divided into 2 branches. The upper branch represented an aberrant artery whereas the lower branch gave 5 divisions. The left renal artery also divided into 2 branches much before the hilum as anterior and posterior divisions. The anterior branch took an arched course and gave 6 branches. The posterior branch gave 3 terminal branches before entering the renal substance. In addition to anomalous hilar structures, normal architecture of both kidneys was altered and the hilum of the left kidney was found on its anterior surface.
Kidneys are a pair of excretory organs situated one on each side of the vertebral column retroperitoneally. Being with a bean shape, it presents thick and rounded superior pole and thin and pointed inferior pole. Renal hilum is deep vertical slit situated in its medial border which lies about 5 cm from the midline opposite the lower border of L1 vertebra. It communicates with the renal sinus within the kidney [
Knowing the anatomy of the ureteropelvic junction of the kidney is essential for understanding urinary tract disorders and various nephron sparing surgical procedures. The present study describes the bilateral anomalous arrangement of the structures at the hilum of kidney which is of clinical and surgical relevance.
During dissection of about 60-year-old male cadaver, we observed anomalous positions and branching pattern of the renal vessels causing a congested renal hilum. The variation was bilateral (Figure
Anomalous vascular branching pattern and their course in the hila of bilateral kidney. IVC: inferior vena cava, AA: abdominal aorta, RU: right ureter, RTV: right testicular vessels, LTV: left testicular vessels, RRV: right renal vein, LRV: left renal vein, and LSRV: left supra renal vein.
Renal artery (RA) with its normal origin and course from abdominal aorta divided immediately into 2 branches (Figure
Right kidney: showing congested hilum due to multiple branching pattern of renal artery (RA). AA: aberrant artery, RV: renal vein, IVC: inferior vena cava, and U: ureter.
The hilum was wide and situated on the anterior surface instead of its normal anatomical situation in the medial border (Figure
Left kidney: showing congested hilum and distorted shape of the kidney. RA: renal artery, RV: renal vein, IVC: inferior vena cava, U: ureter, and LTV: left testicular vein.
Left renal artery arose from abdominal aorta, before entering the hilum branched into 2 divisions. Anterior division presented an arched course superficial to the tributaries of renal veins and gave 6 branches. The upper 2 branches of it represented the aberrant arteries and entered the upper pole of the kidney. One of the aberrant arteries before piercing the substance of the kidney gave the right inferior suprarenal artery. The posterior division ran behind the renal pelvis and posterior division of renal vein and gave 3 branches. So altogether, 8 branches pierced the renal hilum and 2 branches pierced the upper pole of the kidney.
Anterior and posterior tributaries of renal vein after emerging separately from hilum of the left kidney united to form a single trunk that drained into inferior vena cava. Before the union, the posterior division joined the anterior division in a twisted manner. Anterior division received left testicular vein (LTV). The left suprarenal vein (LSRV) drained into the trunk of the left renal vein. So the arrangement of the structures in the hilum of left kidney from anterior to posterior aspect was anterior division of the renal vein-anterior division of renal artery-renal pelvis-posterior division of renal vein-posterior division of renal artery (A-V-P-V-A).
The schematic representation of bilateral renal hilar pattern with distorted shapes of kidneys is shown in Figure
Schematic representation of bilateral renal hilar pattern with distorted shapes of kidneys. AA: aberrant artery, RA: renal artery, RV: renal vein, LGV: left gonadal vein, LSV: left suprarenal vein, and LISA: left inferior suprarenal artery.
Although abnormal shapes, positions, and vascular variations of the kidney have been reported earlier, to our knowledge, there are no reports on bilateral anomalous variations of the renal vessels as presented in this paper. The variations reported here are peculiar and unique. Variations in the branching pattern of the renal vessels probably might be the cause for the change in the shape of the kidney from the normal bean shape to the retort flask shape which is seen here. Morishima et al. reported a diamond shaped left kidney situated lower than usual, the hilum of which was widely opened and was facing anteriorly [
The abnormalities in the renal arteries are mainly due to the various developmental positions of the kidney [
Study conducted by Kaneko et al. presented 25% of multiple renal arteries which included the polar renal arteries [
Rouvière et al. observed 29%–65% incidences with anomalous course of renal vessels crossing the renal pelvis cause of ureteropelvic obstruction [
The authors would like to thank Ms. Sheetal Mohan, Lecturer, MMMC, and Mr. Ganesh Prasad, KMC, for their art work.