What is a renal MAG3 scan?
A renal MAG3 (Mercaptuacetyltriglycine) scan is a diagnostic nuclear medicine test that allows your child’s doctor to see his kidneys and learn more about how they are functioning.
Aradiopharmaceutical called Technetium-99m MAG3 is injected into one of your child’s veins. Technetium-99m MAG3 has a tiny amount of radioactive molecules in it.
A special camera, called a gamma camera, is used to take pictures of the kidneys once the radiopharmaceutical has been injected.
When might a renal MAG3 scan be needed?
A renal MAG3 scan can help:
- detect and evaluate hyrdronephrosis
- determine relative (differential) renal function in the right and left kidneys
- detect and evaluate obstruction in the renal collecting system
- detect acute tubular necrosis
- evaluate renal function in children allergic to radiographic contrast
- evaluate renal perfusion and function in certain cases of renal immaturity
- evaluate renal trauma
How should I prepare my child for a renal MAG3 scan?
- Please let us know if your child takes a diuretic (water pill).
- It is helpful to give your child a simple explanation as to why a MAG3 scan is needed and assure him that you will be there for the entire time.
- You may want to bring your child’s favorite book, toy or comforting object to use during waiting times.
- We have various videos or DVDs to choose from for your child to watch during the procedure or you can bring one from home.
What should I expect when I bring my child to the hospital for a renal MAG3 scan?
When you arrive, please go to the Nuclear Medicine check-in desk on the second floor of the main hospital or the first floor check-in desk at our Waltham facility. A clinical intake coordinator will check in your child and verify his registration information.
What happens during a renal MAG3 scan?
- You will be greeted by one of our nuclear medicine technologists who will explain to you and your child what will happen during the study.
- To perform the examination, an IV catheter is placed in one of your child's veins.
- After the IV insertion, in some cases a bladder catheter will be inserted. The catheter will keep the bladder empty during the entire procedure.
- The technologist will then inject the radiopharmaceutical through the IV and begin imaging.
- Imaging continues for 20 minutes and a nuclear medicine physician will determine if a second phase, called a diuretic renogram, needs to occur.
- If so, this involves administering a diuretic called Lasix (Furosemide) through the same IV. This diuretic will cause your child's kidneys to make more urine than normal for a short period of time.
- It is important that your child remains as still as possible to obtain the best quality images.
Will my child feel anything during a renal MAG3 scan?
Your child may feel discomfort with the placement of the catheter. Our personnel are aware of the sensitive nature of the area to be tested and every effort is made to ensure privacy and to make sure the patient is as comfortable as possible.
Your child may experience some discomfort associated with the insertion of the intravenous needle. The needle used for the procedure is small. Once the radiopharmaceutical is injected and the scan is complete, the needle will be withdrawn and a gauze bandage with adhesive tape will be placed over the site of the injection. The area where the injection was given may be a little sore.
Although the camera may appear large and intimidating, it does not touch your child.
Is a renal MAG3 scan safe?
We are committed to ensuring that your child receives the smallest radiation dose needed to obtain the desired result.
- Nuclear medicine has been used on babies and children for more than 40 years with no known adverse effects from the low doses employed.
- The radiopharmaceutical contains a very tiny amount of radioactive molecules. We believe that the benefit to your child’s health outweighs potential radiation risk.
- The camera used to obtain the images does not produce any radiation.
What happens after the renal MAG3 scan?
Once the scan is complete, the images will be evaluated for quality. If the scan is adequate, your child will be free to leave and resume normal activity.
One of the Boston Children's nuclear medicine physicians will review your child’s images and create a report of the findings and diagnosis.
How do I learn the results of the renal MAG3 scan?
The nuclear medicine physician will provide a report to the doctor who ordered your child’s renal MAG3 scan. Your child’s doctor will then discuss the results with you.