What are the common imaging tests to evaluate renal artery stenosis?
An angiogram of the renal arteries is the best test available to detect the degree of narrowing. This is similar to an angiogram of the heart and involves insertion of a catheter through the groin into the main artery (the aorta), that is advanced to the level of the renal arteries. A dye is injected, and x-ray images are taken to see the caliber of the blood vessel and extent of the narrowing. An angiogram is considered an invasive test (insertion of the catheter inside the body) and therefore is not widely used because of the risk of complications. This test also may not determine if narrowing is truly significant to cause the problem or not, and so it may be necessary to combine this with a functional test. Generally, a narrowing of greater than 75% by angiogram is considered significant enough to cause high blood pressure or kidney dysfunction. An additional advantage of an angiogram is that if a treatable narrowing is seen, it may be fixed at the same time via angioplasty or by pl
