Radiographic evaluation of the renal vasculature

Renal artery stenosis is an important cause of hypertension and progressive renal insufficiency. Additionally, there is increasing concern that renovascular disease is a significant, but previously unrecognized, cause of end-stage renal disease in certain subsets of patients. Advances in revascularization techniques offer a greater opportunity for blood pressure control and for the restoration or preservation of renal function. Accurate imaging of the renal vasculature, however, is essential for the proper selection of those individuals who might best benefit from such intervention. Although conventional or digital subtraction arteriography remains the gold standard diagnostic test, significant advances in non-invasive imaging techniques now offer the clinician several options for the accurate diagnosis of hemodynamically significant renovascular disease. These techniques include captopril renography, duplex ultrasonography, magnetic resonance angiography, and spiral/fast computed tomography. In this review, the advantages and limitations of these imaging techniques are compared and contrasted with an emphasis on their usefulness in screening for renovascular disease. Also reviewed are recent applications of these techniques for measurement of renal function, predicting outcome of revascularization, and the clinical monitoring of patients with renovascular disease managed either medically or by revascularization.