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Renal perfusion scintiscan How the Test is Performed:
You are asked to lie on the scanner table. Pressure (from a tourniquet or blood pressure cuff) is applied to the upper arm, which distends the veins of the arm. The inner elbow is scrubbed with antiseptic, and a small amount of radioisotope (technetium Tc 99m
glucoheptonate) is injected into a vein. The pressure on the upper arm is then released, which allows the isotope to travel through the bloodstream as a small, concentrated "package." A short time later, the kidneys are scanned. Several images are taken, each lasting 1 or 2 seconds, with the total scan time about 30 minutes. The images are taken as the radioactive material flows through the renal arteries.
After the scan, no recovery time is required. You may be asked to drink plenty of fluids and urinate frequently to help excrete the radioactive material from the body.
How to Prepare:
There is usually no need for fasting, special diets, or preliminary medications.. You may be asked to drink additional fluids before the scan.
You must sign a consent form. You will wear a hospital gown. Remove jewelry, dentures, and metallic objects before the scan.
Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experience, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:
How it Feels:
There is a sharp prick when the isotope is injected into the vein. You do not feel the isotope. You do not feel the scan, although the table may be hard or cold. You will need to lie still during the scan.
Risks:
The risks are essentially the same as for X-rays (radiation) and for needle pricks ( venipuncture ).
There is a slight amount of radiation from the radioisotope . Most of this radiation exposure occurs to the kidneys and bladder as the isotope is excreted. Virtually all radiation is gone from the body in 24-hours. However, because of the slight exposure to radiation, caution is advised if you are pregnant or breast feeding.
Any time the body is penetrated (such as by a needle prick) there is a risk for infection. Injection into a vein also carries a slight risk for bleeding . The risk is no greater for renal perfusion scan than for intravenous injection of any sort.
Extremely rarely, a person will exhibit an allergic reaction to the radioisotope, which may include severe anaphylaxis .
Why this Test is Performed:
The test evaluates blood flow through the kidneys, particularly when there is known sensitivity to the contrast media used in IVP or similar tests, or when there is an underlying kidney insufficiency (reduced kidney function).
Normal Values:
Normal blood flow through the renal vessels is desired.
Abnormal Results:
A decreased uptake may indicate renal artery stenosis .
Cost:
The estimated cost is $548.
Special Considerations:
If there are signs of reduced kidney function and renal perfusion is normal, a complete renal scan may be performed.
The kidneys are responsible for removing wastes from the body, regulating electrolyte balance and blood pressure, and the stimulation of red blood cell production. The gross anatomical structure of the kidney is illustrated.
This is the typical appearance of the blood vessels (vasculature) and urine flow pattern in the kidney. The blood vessels are shown in red and the urine flow pattern in yellow.
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