The role of subtraction angiography in the diagnosis of distal aorta occlusion following CT urography: A case report

Distal aortic occlusion is rare; and because many cases are left undetected due to an asymptomatic early stage, its prevalence is currently unknown. In this report, we present a case of a 53-year-old man with history of hypertension and tobacco usage who was referred to our ambulatory imaging center for advanced computerized tomography (CT) urography evaluation after presenting abdominal pain consistent with renal calculi. The CT urography showed left kidney stones - confirming the initial clinical suspicion of the referring physician. As incidental findings, the CT also revealed occlusion of the distal aorta, the common iliac arteries, and the proximal external iliac arteries. Based on these findings, we performed an angiography procedure that confirmed the total occlusion of the infrarenal abdominal aorta at the level of the inferior mesenteric artery. At this level, multiple collaterals and anastomosis with pelvic vessels were found. The therapeutic intervention without the angiography results could have been not optimal based on the CT urography alone. Thus, this case highlights the value of the subtraction angiography for accurate diagnosis of distal aortic occlusion following a suspicious incidental finding in CT urography.