A renal angiogram is often used to help diagnose conditions involving narrowed blood vessels to the kidney.  The procedure is typically performed in patients who have elevated blood pressure or impaired kidney function—both ailments resulting from blocked vessels.  Because in most cases, blood vessels are hard to detect using a regular x-ray, an angiogram is used whereas a special dye is injected in the arteries through a tube called a catheter so that all of the vessels will appear by a contrast allowing the physician to take an immediate x-ray picture in order to examine the vessels.  Based on the diagnoses from the renal angiograph, patients might be candidates for angioplasty—the repair of the blocked vessels and artery using a balloon. This particular angiogram test usually does require a short hospital stay and is performed with a local anesthesia.