MIBG Scan

What is a MIBG Scan?

An MIBG scan is a test that helps locate and diagnose certain types of tumors. It can also show when cancer responds to therapy.

The letters MIBG stand for meta-iodobenzylguanidine. It is a molecule that is absorbed by some tumors, particularly neuroblastoma.

The scan can show neuroblastoma inside the body. It also shows when it has spread to the bone and other organs.

How Long Does a MIBG Scan Take?

The test has 2 parts conducted over 2 days. Patients do not have to be admitted into the hospital for the test.

How Does a MIBG Scan Work?

Here’s how the scan works:

The first day of the test

Your child will receive an injection of a tracer. It includes the MIBG compound combined with a very small amount of a radioactive substance (radioactive iodine).

Neuroblastoma cells should absorb the tracer and show up when scanned the next day.

The second day of the test

Your child will have the scan. It uses a gamma camera that takes pictures of areas that absorbed tracer.

Doctors look for bright spots. The bright spots may indicate cancer.

What Happens During the MIBG Scan?

Every center is different, but these general tips can help you prepare:

On the first day

• Your child will receive an injection of the tracer through a vein.
• You and your child can return to patient housing (or home) after the injection.
• There is a 24-hour waiting period to allow time for the tracer to concentrate in sites of tumor.

On the second day

• You and your child will return to the center for the scan.
• Your child will lie on a table during the test and will need to stay still. The test can last 1-2 hours, depending on your child’s height.
• The technologist or nurse will secure your child with soft, safety belts. The table will slowly move through a device called a scanner.
• An MIBG scan does not hurt. But if your child finds it difficult to stay still, sedation might be needed. That’s because if your child moves, the scan will blur and must be repeated.
• After the test, your child may leave and resume normal activities, unless they were sedated. Patients who are sedated must recover from anesthesia.

What Should we do Before a MIBG Scan?

Here are steps to help be sure your child is ready for a MIBG scan:

• Let the care team know about medications, allergies, and medical conditions: Tell your child’s treatment team about:
  • Allergies
  • Other medical conditions
  • Medications (even over-the-counter ones)
  • If there is any chance of pregnancy

• Check insurance: Check with your insurance provider in advance to find out how much of the test’s cost will be covered. They can also tell you how much you’ll need to pay.
• Ask questions: Talk with the care team about any concerns or questions.
• Explain procedure to your child: Make sure your child knows the reason for the MIBG scan. You may want to consult a child life specialist to help.
• Take prescribed medicine to protect thyroid: The doctor may prescribe potassium iodide drops to start taking before the injection until the day after the scan. The drops protect the thyroid from absorbing any of the radioactive iodine that is part of the MIBG.

Day of the injection

• You should arrive a few minutes early to allow time for check-in.
• You may be asked to sign a consent form. It states that you understand the benefits and risks of the scan and agree to have the test.
• You and your child will wait in the waiting area until your child is called. A nurse or nuclear medicine technologist will greet you and explain what will happen. A child life specialist may be there as well.
• First, a nurse or technologist will inject the tracer through an IV.
• After the injection, the IV will be removed. Then you may leave the area and resume normal activities.
• Pregnant women should not have direct contact with the patient from the time of the MIBG injection until instructed by the nuclear medicine staff. Most often, this is about 12 hours.

Before a MIBG scan

• Your child should wear loose, comfortable clothing and leave jewelry and metal objects at home. Your child may be asked to wear a hospital gown.
• You should arrive a few minutes early to allow time for check-in.
• You will wait in the waiting area until your child is called. A nurse or nuclear medicine technologist will greet you and explain what will happen. A child life specialist may be there as well.
• Your child will lie on a table of the scanner. A gamma camera will take pictures that will help the doctors tell if there is cancer is and if it has spread to bones or other parts of the body.

How Will we Receive the Results From a MIBG Scan?

The results of the scan will be interpreted by a nuclear medicine physician. The doctor will prepare a report and share it with the physician who ordered the test.

Your child’s oncologist will share the results with you.