Anatomical Variations of Renal Arteries: Clinical, Radiological, and Surgical Considerations

To synthesize the current knowledge regarding the embryological basis, anatomical classification, imaging characterization, and clinical implications of accessory renal arteries.

Anatomical variations in the renal arteries are common, affecting approximately 20-35% of the population, and have significant implications for clinical outcomes and surgical planning. Accessory renal arteries are usually terminal vessels that serve discrete renal islands with minimal collateral circulation in the body; therefore, their preoperative identification is important. However, there has been no modern synthesis of embryology, imaging, and multidisciplinary clinical treatment for these variations.

A narrative review of the literature was conducted by searching PubMed and Google Scholar for publications from December 2015 to December 2025. MeSH terms and free-text keywords related to "accessory renal artery," "multiple renal arteries," "renal artery variations," "renal vascular anatomy," "kidney transplantation," "renovascular hypertension," "computed tomography angiography," "magnetic resonance angiography," and "endovascular aortic repair" were used in Boolean combinations. Peer-reviewed original studies, systematic reviews, meta-analyses, and case series were included. Conference abstracts, unpublished data, and non-English publications were excluded.

This review addresses the embryological basis and anatomical classification of accessory renal arteries; the diagnostic roles of Doppler ultrasound, computed tomography angiography, and magnetic resonance angiography; and their clinical implications in kidney transplantation, partial nephrectomy, and endovascular aortic repair, including the contested association with renovascular hypertension. Available data suggest that most accessory vessels do not independently cause hypertension, whereas stenosis of larger vessels may be a correctable etiology in selected cases.

Accessory renal arteries have a significant clinical impact, primarily determined by the size of the vessels and the area of the kidney they supply. Preoperative characterization based on modern imaging can be reliable and can help plan and manage surgery for each patient. More prospective research is required to establish evidence-based principles for vessel maintenance and evaluate new technologies in this context.