Renal scan

Alternative names:

kidney scan; renogram

What the risks are:

The risks are essentially the same as for X-rays (radiation) and for needle pricks.

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.

Special considerations:

Findings of reduced function may be nonspecific in identifying the cause of the dysfunction. Congenital (or other) abnormalities of kidney shape or size may contribute to an error in interpreting results of a renal scan, because glomerular filtration rate and other functions are calculated based on the presumption of normal anatomic size and shape. Tests of some functions may require delayed images (1 to 4 hours later).

Advantages include the ability to determine kidney function without exposure to contrast agents and the ability to obtain quantitative information that may not be obtainable by other procedures.