Renal perfusion is a term used to describe blood flow to the kidneys and is commonly assessed with a test called renal scintigraphy. This test helps determine how well blood is delivered to the kidneys and how well the kidneys function, according to Johns Hopkins University.
In the case of renal perfusion assessment, a renal blood flow scan can help find blockages or narrowing of blood flow to the kidneys. This is an important test in cases where a physician wants to rule out renovascular hypertension as a source of disease or if renal transplant rejection is suspected, explains Johns Hopkins University.
The procedure begins by injecting a small amount of radioactive dye into the blood stream. The dye usually consists of iodine or technetium and is processed by the kidneys. Once there, the dye emits radiation, which is picked up by a scanner. The scanner then translates the information into an image, which a physician interprets, according to Johns Hopkins University.
The risks from the procedure are low because of the small amount of dye injected into the patient. Patients who are allergic to the dye or any of its components need to tell their physicians. Women who are pregnant should avoid being exposed to the dye because it can cause harm to the fetus, explains Johns Hopkins University.