ANATOMICAL VARIATIONS OF SEGMENTAL AND ACCESSORY RENAL ARTERIES: A CADAVERIC, CORROSION CAST, AND RADIOLOGICAL STUDY.

Background: Segmental and accessory renal arteries play a crucial role in determining the vascular supply of the kidney. Their variations are of immense clinical relevance in nephron-sparing surgery, renal transplantation, and urological interventions. Objective: To document the anatomical variations of apical, upper, middle, lower segmental arteries and accessory renal arteries in 60 adult human kidneys. Methods: Sixty kidneys (40 cadaveric dissections, 10 corrosion casts, 10 radiological studies) were examined. Segmental arteries and accessory renal arteries were identified and classified. Their frequency and patterns were compared with previous anatomical studies. Results: The apical segmental artery was present in 93.3% of cases, with origin predominantly from the anterior division. Variations included dual apical arteries (6.7%). Upper segmental arteries were observed in 90% of specimens, often arising from the anterior division, with accessory branches in 10%. Middle segmental arteries showed the highest variability: single in 70%, double in 20%, and absent in 10%. Lower segmental arteries were consistently present, though accessory lower segmental arteries occurred in 8.3%. Accessory renal arteries were noted in 15% of specimens, arising either directly from the aorta or as extra branches of the main renal artery. Most accessory arteries supplied the upper or lower poles. Conclusion: Segmental and accessory renal arteries demonstrate significant anatomical variability. Awareness of these patterns is vital in planning renal transplantation, managing hydronephrosis, and performing partial nephrectomy. Preoperative imaging should evaluate these arteries to reduce surgical risks.