Left infrarenal region: anatomic variants, pathologic conditions, and diagnostic pitfalls.
Computed tomography (CT) is the preferred method for evaluating the left periaortic infrarenal region. Structures larger than 11 mm in cross-sectional diameter in this region are considered abnormal and should be evaluated for lymphadenopathy, hydroureter, or a vascular abnormality such as venous thrombosis or varicoceles. Normal structures include inferior mesenteric vessels, left gonadal vein and artery, and ureter. The diagnostic process may be complicated by variations in anatomy, including double inferior vena cava, left inferior vena cava, retroaortic left renal vein, circumaortic left renal vein, horseshoe kidney, crossed-fused renal ectopia, renal agenesis, and ureteral duplication. Familiarity with the anatomy of this region and awareness of normal variants are necessary to avoid errors in diagnosis. Radiologists should also be aware of problems in CT technique (nonopacified bowel, dynamic and unenhanced scanning) that can confuse the diagnosis.
Gay
S B
SB
Department of Radiology, University of Virginia Health Sciences Center, Charlottesville 22908.
Armistead
J P
JP
Weber
M E
ME
Williamson
B R
BR
D000783:Aneurysm / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D007668:Kidney / Q000002:abnormalities* / Q000000981:diagnostic imaging; D008206:Lymphatic Diseases / Q000000981:diagnostic imaging; D008297:Male; D012077:Renal Artery / Q000002:abnormalities* / Q000000981:diagnostic imaging; D012082:Renal Veins / Q000002:abnormalities* / Q000000981:diagnostic imaging; D013927:Thrombosis / Q000000981:diagnostic imaging; D014057:Tomography, X-Ray Computed; D014513:Ureter / Q000002:abnormalities* / Q000000981:diagnostic imaging; D014646:Varicocele / Q000000981:diagnostic imaging; D014682:Vena Cava, Inferior / Q000002:abnormalities* / Q000000981:diagnostic imaging