Nature of crossing vessels in patients with radiographically normal ureteropelvic junctions: Prevalence and anatomic characteristics

Objective: To evaluate the prevalence and characteristics of crossing vessels in asymptomatic patients with a radiographically normal ureteropelvic junction. Materials and Methods: We retrospectively reviewed the computed tomography angiography images of 601 patients who were evaluated for possible living organ donation at the University of Minnesota from 2005 to 2008. One patient had asymptomatic hydronephrosis and was excluded from the analysis. The prevalence and characteristics of crossing vessels at the ureteropelvic junction were determined, including vessel location, origin, size, distance from the ureteropelvic junction, and vessel type (artery or vein). Results: The prevalence of crossing vessels at the radiographically normal ureteropelvic junction was 22.7%. A total of 163 crossing vessels were present in 136 patients; 60.1% were left-sided and 39.9% were right-sided. Arteries accounted for 81.0% of the crossing vessels and veins for 19.0%. Accessory lower pole renal vessels originating from the great vessels constituted 59.5% of the crossing vessels. The location of the crossing vessel relative to the ureteropelvic junction varied and included anterior (25.8%), anterolateral (36.8%), medial (14.6%), anteromedial (2.5%), lateral (12.9%), and posterior (7.4%). The mean diameter and mean distance of the crossing vessel from the ureteropelvic junction was 3.3 mm and 1.8 mm, respectively. Conclusion: The prevalence of crossing vessels in asymptomatic, healthy patients with a radiographically normal ureteropelvic junction was 22.7%, lower than that seen in association with ureteropelvic junction obstruction. The location of the crossing vessels varied about the ureteropelvic junction, and no location was consistently free of traversing vessels.