Copyright: ©Author(s) 2026. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial (CC BY-NC 4.0) license. No commercial re-use. See permissions. Published by Baishideng Publishing Group Inc.
World J Radiol. Oct 28, 2026; 18(10): 127348
Published online Oct 28, 2026. doi: 10.4329/wjr.127348
Aberrant renal vessels crossing the ureter and the ureteropelvic junction: A retrospective computed tomography-based analysis of non-obstructed population
Ioannis Paschopoulos, George Triantafyllou, Daniel Gondorf, Nikolaos-Achilleas Arkoudis, Georgios Velonakis, Chrysovalantis Mariorakis, Christos Lyrtzis, Kostis Gyftopoulos, Maria Piagkou
Ioannis Paschopoulos, George Triantafyllou, Daniel Gondorf, Chrysovalantis Mariorakis, Maria Piagkou, Department of Anatomy, School of Medicine, Faculty of Health Sciences, National and Kapodistrian University of Athens, Athens 11527, Attikí, Greece
Nikolaos-Achilleas Arkoudis, Georgios Velonakis, Research Unit of Radiology and Medical Imaging, National and Kapodistrian University of Athens, Athens 115 28, Attikí, Greece
Christos Lyrtzis, Department of Anatomy and Surgical Anatomy, School of Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, Thessaloniki 54124, Kentrikí Makedonía, Greece
Kostis Gyftopoulos, Department of Anatomy, School of Medicine, Faculty of Health Sciences, University of Patras, Patra 26504, Dytikí Elláda, Greece
Author contributions: Paschopoulos I wrote the first draft of the manuscript; Triantafyllou G contributed to study conceptualization and data collection; Arkoudis NA performed radiological data collection; Paschopoulos I, Gondorf D, Velonakis G, Mariorakis C, and Lyrtzis C carried out data analysis; Gyftopoulos K and Piagkou M supervised the entire study; Triantafyllou G, Gondorf D, Arkoudis NA, Velonakis G, Mariorakis C, Lyrtzis C, Gyftopoulos K, and Piagkou M contributed to manuscript review and editing; and all authors commented on previous versions of the manuscript, contributed to manuscript revision, and approved the final manuscript.
AI contribution statement: Declaration of generative AI and AI-assisted technologies in the manuscript preparation process: During the preparation of this work the authors used Google Gemini 3.1 PRO in order to generate text and to perform language editing. After using this tool, the authors reviewed and edited the content as needed and take full responsibility for the content of the published article.
Institutional review board statement: This study was approved by the Medical Ethics Committee of National and Kapodistrian University of Athens, approval No. 1037.
Informed consent statement: Informed consent was obtained from all subjects involved in the study.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Data sharing statement: Please contact the corresponding author for data requests.
Corresponding author: George Triantafyllou, MD, Department of Anatomy, School of Medicine, Faculty of Health Sciences, National and Kapodistrian University of Athens, 75 Mikras Asias Street, Goudi, Athens 11527, Attikí, Greece.
georgerose406@gmail.com
Received: August 28, 2026
Revised: September 22, 2026
Accepted: October 16, 2026
Published online: October 28, 2026
Processing time: 62 Days and 8.3 Hours
BACKGROUND
Crossing renal vessels are recognized as potential extrinsic contributors to ureteropelvic junction obstruction; however, their prevalence and morphological characteristics in adults without urinary tract obstruction remain incompletely characterized.
AIM
To determine the prevalence, vascular composition, morphological patterns, and spatial relationship of renal vessels crossing the ureteropelvic junction (UPJ) or proximal ureter using contrast-enhanced computed tomography (CT).
METHODS
A retrospective review of 197 adult patients (394 kidneys) with normal urological anatomy who underwent contrast-enhanced abdominal CT was conducted. Multiplanar and three-dimensional reconstructions were evaluated to document crossing vessel prevalence, etiology (arterial, venous, or combined), specific anatomical variations (early bifurcations or accessory vessels), spatial orientation (anterior/posterior), and exact intersection distance to the ureteropelvic.
RESULTS
Crossing vessels were identified in 56 of 394 renal units (14.2%), affecting 43 of 197 patients (21.8%), exhibiting a significant male predominance (69.6%, P = 0.007). Presentations were unilateral in 69.8% and bilateral in 30.2% of cases. Arterial anomalies predominated (64.3%), mostly due to early main renal artery bifurcations, while combined arterio-venous crossings occurred in 25% of cases. The spatial orientation was overwhelmingly anterior (98.2%). Direct UPJ intersection (0 mm) was observed in 37.5% of cases, whereas distal ureteral intersections occurred at a mean distance of 16.2 ± 4.5 mm from the junction.
CONCLUSION
Renal vessels crossing the UPJ or proximal ureter are not uncommon incidental anatomical findings on contrast-enhanced CT in adults without obstruction. Their baseline prevalence in an unobstructed cohort highlights that crossing vessels can exist without concurrent obstruction. Contrast-enhanced CT provides detailed anatomical mapping of the vascular course, which may support preoperative planning and help mitigate the risk of inadvertent vascular injury when surgical intervention is indicated. Nevertheless, functional assessment remains necessary when clinically significant obstruction is suspected.
Core Tip: This retrospective contrast-enhanced computed tomography study evaluated 197 adult patients with normal urinary tracts to determine the prevalence and morphology of renal vessels crossing the ureteropelvic junction. Crossing vessels were identified in 14.2% of cases, exhibiting a significant male predominance. These vessels were predominantly driven by anterior-crossing arterial anomalies, particularly early main renal artery bifurcations. The substantial baseline prevalence of these crossing vessels in unobstructed kidneys indicates that these vessels can occur incidentally without associated obstruction. While this study does not evaluate functional outcomes, detailed preoperative vascular mapping with contrast-enhanced computed tomography can be a valuable adjunct for surgical planning and mitigate the risk of inadvertent vascular injury.
