[Computerized tomography angiography of the renal vessels]

To present the findings and discuss the diagnostic possibilities of helical CT angiography and digital substraction angiography, and to compare their capabilities to depict renal vascular anatomy (arterial and venous) and the pathological changes.

The findings obtained by the different imaging modalities of CT angiography were compared with those of digital substraction angiography in more than 2000 studies performed at our hospital.

Agreement and correlation between CT angiography and digital substraction angiography, the gold standard, were found in the vast majority of the cases. In conjunction, various image post-processing possibilities of CT angiography achieved almost 100% sensitivity and specificity.

CT angiography is capable of obtaining results that overlap with those of optimum quality digital substraction angiography and is a less invasive and less costly procedure. The time required is shorter and the radiation dose exposure is markedly lower for patient and staff. Helical CT is a minimal invasive technique with an increasing role in the evaluation of the renal vessels. Although its field of applications has not yet been completely established, it is less invasive, less costly, radiation exposure of patient and staff performing the procedure is lower, and has had a considerable impact in the diagnosis and management of vascular disorders. CT angiography is applicable to a number of indications of conventional angiography and has permitted vascular screening studies where one would be reluctant to indicate catheter arteriography. This imaging procedure is mainly used for 1) screening of patients that may have renovascular hypertension that may be amenable to surgical or intraluminal treatment; 2) follow-up of treated patients; 3) preoperative assessment of kidney donors; 4) evaluation of renal artery aneurysms (uncommon), aneurysms extending to the renal arteries or dissection of the aorta. It is also effective, but only slightly superior to conventional CT, in depicting thrombosis or tumor invasion of renal veins, although it is highly effective in evaluating anatomical variations and renal vein anomalies. In inflammatory vascular disease it is similar to catheter angiography, although its impact is not considerable due to the low prevalence of inflammatory vascular disease in our setting.