A Study on Renal Artery Variations by CT Angiography and Their Clinical Importance

Aim This study aimed to evaluate the prevalence, anatomical variations, and branching patterns of the renal arteries using multiphasic computed tomography angiography (CTA), based on the modified classification proposed by Cases et al (2017). Understanding renal artery variations is essential for preoperative planning, renal transplantation, endovascular procedures, and urological interventions. Materials and Methods A retrospective analysis was conducted on 1220 abdominal CTA studies performed between March 2020 and June 2024. Fourteen cases were excluded according to predetermined exclusion criteria, resulting in 1206 studies being included in the final analysis (700 males, 520 females). All examinations were performed using a 128-slice CT scanner (Siemens SOMATOM; syngo CT VC 40). CTA protocols included 5-mm acquisition and 1-mm reconstruction, with administration of 100-120 mL of iodinated contrast at 5-6 mL/s via an 18G antecubital cannula. Post-processing involved multiplanar reformation, volume rendering, and 3D reconstruction. Two experienced radiologists independently reviewed all studies. Renal arteries were categorized into Types A-E and Patterns I-V. “Early division” (Types B and E) and “polar branches” (Types C and D) were further grouped for analytical purposes. Results Among 1206 CTA studies, Type A (normal hilar artery) was the most common in both kidneys, with a slightly higher prevalence on the right (74.29%) than on the left (67.99%). Polar branches were more frequent in the left kidney, whereas early divisions were more common in the right kidney. Pattern 1 was predominant bilaterally (RK: 85.73%; LK: 77.61%), followed by Pattern 2. Significant differences were observed between the kidneys in the distribution of Types A, C, D, and Patterns 1 and 2. Conclusion CTA provides excellent visualization of renal artery variations, enabling precise classification and improving surgical, interventional, and transplant planning. Recognition of these anatomical differences is essential for minimizing procedural complications.