MAG 3 Lasix Renal Scan

A MAG 3 Lasix renal scan (Lasix scan) is provides images of the kidneys to look for kidney function, size, shape, position and blockage of urinary flow. There are no dietary or activity restrictions before or after the renal scan. A renal scan may take up to two hours to complete. We encourage families to bring toys and books to help entertain your child.

What is a Lasix renal scan?

A MAG3 (Mercaptuacetyltriglycine) Lasix renal scan is a nuclear medicine test that provides images of the kidneys to help determine their level of functioning and if there are any obstructions. They can be very important in the diagnosis of hydronephrosis and UPJ obstructions. The test uses Technetium-99m MAG3, a radioisotope. Our team injects it through an IV into the child. A special camera is then used to take photos of the kidneys.

The test places a tracer in the urine and follows it as it goes down into the bladder. In patients who have any blockage or obstruction in the urinary tract, the test shows that the tracer does not drain. This test can take up to an hour and a half.

What happens during the scan?

1. To perform the examination, a specialist places an IV in one of your child’s veins.
2. A pediatrics-trained nurse inserts a foley catheter into the child’s bladder through their meatus (the opening where urine exits the body). A catheter keeps the bladder empty of urine during the test.
3. Then, a CHOC radiology technician injects the radioisoptope through the IV and a large camera takes images of the kidneys. Imaging takes place intermittently for about 20 minutes. The nurse will administer a diuretic (Lasix) to the child through the same IV. Lasix causes the kidneys to produce more urine than normal during a small period of time. The camera will take more images. After the camera takes all the images, nurse will remove the IV and the catheter.

Is the test safe?

CHOC commits to expose our patients to the lowest doses of radiation possible for every procedure.

• Nuclear medicine has been used on infants and children for over 40 years with no known adverse effects from the low doses employed.
• Technetium-99m MAG3 has a tiny amount of radioactive molecules in it.
• The camera used to obtain the images does not produce any radiation.

How do I learn the renal scan results?

Once your test has been completed here at the Center, the child’s family will be notified with the results within two weeks. If you have not heard from our office with test results, please call us at 714-509-3919. If your study was done at a different facility please contact our office upon its completion, so we may obtain the results to review for you.