Nuclear Medicine Renal Scans
Test date____________________ Test time_____________________
This test will be done at the UW Hospital in the Nuclear Medicine section of Radiology. From the clinic entrance, go through the lobby to 2nd floor atrium elevators, then up to 3rd floor. Follow the signs to Radiology.
What is a Renal Scan?
The Renal Scan is a test that studies blood flow to the kidneys and the kidney’s ability to make urine (function). It can also look for blockages of the ureters leading to the bladder. The purpose of this test is to look for signs of poor blood flow, poor function and/or blockages that prevents urine from getting to the bladder.
For your comfort, you will be asked to empty your bladder right before the study. Next, you will be asked to lie on a table that has a camera under it. (The kidneys are better seen from the back.) You will have an IV placed in your arm. You will be injected with a small amount of a radioactive substance while you are lying on the table. Allergic reactions are rare. The nuclear medicine camera will take pictures like a video of the radioactive substance as it moves through your kidneys and into your bladder.
About 30 minutes after the scan starts the Nuclear Medicine doctor will look at your pictures to see if a diuretic such as furosemide should be given to further assess any possible blockage to your bladder. The diuretic increases your need to void. The pictures will continue for about 20 minutes more; less if the need to void is urgent. The urgent need to void is a normal response to the diuretic. You will be allowed to void then a picture is taken. Depending on the diagnosis and your history, you may have a urinary catheter inserted before the scan starts. The whole scan can last 1-2 hours.
Sometimes this scan is used to assess the kidney’s impact on your blood pressure. When this is the reason for the scan, the scan is done twice. The scan is done the same as above. Then, a blood pressure medicine called Captopril is given. About one hour later the second scan is done. Your blood pressure will be taken several times during this one-hour delay and during the second scan.
How do I prepare for this test?
Please tell your doctor if you are pregnant. This test should not be done if you are pregnant or breast-feeding except under special circumstances. You will need to drink, 2 eight-ounce glasses of water or juice, during the 2 hours before the test.
How will I feel after the test?
The test is painless, except for the minor discomfort of having an IV placed. The furosemide can give you an urgent need to go to the bathroom. The longer we can take pictures before you need to use the bathroom the better.
What are the risks?
Many people worry when they hear that the substance used in this test is radioactive. The amount used in this test is so small that there should be no side effects. Again, it should be noted that this test should not be done if you are pregnant or breast-feeding except under special circumstances.
If you have any questions before the test, please call:
UWHC Radiology: Monday-Friday 0800-4:30, (608) 263-XRAY (9729).
Toll free 1-800-323-8942; ask for Radiology.
The information provided should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Any duplication or distribution of the information contained herein is strictly prohibited.
Last Updated: 08/25/2011
Copyright © 08/25/2011 University of Wisconsin Hospitals and Clinics Authority. All rights reserved. Produced by the Department of Nursing. HF#7240
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