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Renal scan
Definition:
A renal scan is a nuclear medicine examination that uses small amounts of radioactive materials (radioisotopes) to measure the function of the kidneys. Alternative Names:
Renogram; Kidney scan Text Continues Below
How the test is performed:
A renal scan is similar to (and in fact, may be a continuation of) a renal perfusion scintiscan. You will be 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 is injected into a vein (the radioisotope used may vary depending on the portion of kidney function that is of particular interest in the study). 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 to 1 hour. The images are analyzed by a computer after the scan is completed and can give detailed information about particular kidney functions (such as glomerular filtration rate, which reflects how much blood the kidney filters over time). 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 for the test:
There is usually no need for fasting, special diets, or preliminary medications. Discuss with your health care professional any nonsteroidal anti-inflammatory drugs (NSAIDs) or blood pressure medications you are currently taking to see if they will interfere with the exam. You may be asked to drink additional fluids before the scan.
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