How It Feels
You may feel nothing at all from the
needle puncture when the tracer is injected, or you may feel a brief sting or
pinch as the needle goes through the skin. Otherwise, a kidney scan is usually
painless. You may find it hard to remain still during the scan. Ask for a
pillow or blanket to make yourself as comfortable as possible before the scan
The test may be uncomfortable if you are having kidney
pain. Try to relax by breathing slowly and deeply.
Allergic reactions to the radioactive
tracer are rare. Most of the tracer will be eliminated from your body (through
your urine or stool) within a day, so be sure to promptly flush the toilet and
thoroughly wash your hands with soap and water. The amount of radiation is so
small that it is not a risk for people to come in contact with you following
Occasionally, some soreness or swelling may develop at
the injection site. These symptoms can usually be relieved by applying moist,
warm compresses to your arm.
There is always a slight risk of
damage to cells or tissue from being exposed to any radiation, including the
low level of radiation released by the radioactive tracer used for this test.
A kidney scan is a
nuclear scanning test that is done to check
kidney function or appearance. The results of a kidney
scan are usually available in 2 days.
The radioactive tracer flows evenly to and
through each kidney at the same time. The kidneys are working
The tracer flows from the kidneys into the urine, which then drains into the
bladder. This process occurs within a normal time
The kidneys take up the
radioactive tracer evenly. No "hot" spots or "cold" spots are seen.
The kidneys are not normal in shape, size,
The tracer does not flow evenly through the
kidneys, meaning narrowing of, blockage of, or damage to the blood vessels
or tissue in the kidneys. This may also mean poor kidney function.
The tracer collects in
an area ("hot" spot) of a kidney. This might mean a tumor containing a
higher-than-normal number of blood vessels.
An area of the kidney
does not take up the tracer ("cold spot"). This may mean an
cyst, or scarring.
The tracer does
not pass from the kidneys into the urine and then through the ureters to the
bladder. This can mean the movement of urine from the kidney is blocked.
What Affects the Test
Reasons you may not be able to have the test or why the results may not be helpful include: