How It Is Done continued...
will scan for radiation right after the radioactive tracer is injected. Scans
may be taken every few minutes for about 30 minutes. More pictures may be taken 1 to 2 hours after the tracer was injected. The scans produce pictures
as the tracer moves through your kidneys. You may also be given medicine to
help the scans check for certain kidney functions.
A chart called
a renogram may be made using the information from the kidney scan by
plotting the movement of the tracer through the kidneys and recording it on a
graph. A series of chart recordings is then made based on the amount of tracer
uptake in the kidneys over a period of time. These recordings provide
information about different phases of blood flow and kidney function.
A kidney scan usually takes about 30 minutes to 1 hour.
You need to remain very still during each scan to avoid
blurring the pictures. The camera does not produce any radiation, so you are
not exposed to any more radiation while the scan is being done.
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.