A whole-body MIBG scan zeroes in on tumors affecting specific types of nerve tissues—the most common ones being pheochromocytoma and neuroblastoma tumors. It has two main components: a liquid radioactive material (iodine-123-metaiodobenzylguanidine or simply “MIBG”) that is injected into a vein and a special gamma camera, which scans the entire body to locate the tumors and determine whether or not the cancer has spread.
The actual test is conducted over two days, as an outpatient procedure in a hospitals’s nuclear medicine department. Day 1 is for the injection of a small dose of MIBG into a vein in your arm or hand, which typically takes 15 minutes. To ensure that the MIBG has spread throughout your body, the scan is conducted four hours later. During the scan, you’ll be lying on a bed with a large camera moving over your body for 60 to 90 minutes.
Day 2 is for another head-to-toe MIBG scan, this time without any injection. The scan lasts an hour or two. Images from the first- and second-day MIBG scans will be evaluated by a nuclear medicine physician, who provides a final report to your doctor after five to seven days.
Of course, as with any nuclear medicine test, there are precautions to follow before having a whole-body MIBG scan. You must, for instance, inform your doctor beforehand of any medications you’re on (specific types may interfere with the scan and should be stopped days before the test). You do, however, need to take potassium iodide tablets or Lugol’s iodine solution, as prescribed, to ensure your thyroid gland doesn’t absorb too much radioactivity. And in case you’re pregnant (or might be), are breastfeeding, or are caring for small children, let the medical staff know so they can advise and guide you accordingly.