Thanks for writing. Your blood tests indicate that you have primary hyperparathyroidism. You have a calcium level that is high for your age, with a high PTH.

Most of the time, primary hyperparathyroidism is caused by a benign parathyroid tumor, or adenoma. The treatment for this is removal of the parathyroid tumor. Sometimes, imaging can show which parathyroid gland is diseased. Your doctor is suggesting that you should get a scan to determine which gland is bad, so you can then proceed to surgery.

Unfortunately, imaging for parathyroids is not always accurate. Parathyroid tumors do not always show up on scans, even when they are there. And you could also have multiple tumors, with only one (or none) showing up on the scan. You will need surgery whether or not the parathyroid tumor shows up on a scan.

Scans can be helpful for ruling out parathyroid tumors in unusual locations. Sometimes parathyroid tumors can be down in the chest, and you want to know about that before the operation. A sestamibi scan can show you that. But even if all scans are negative, surgery is still needed.

A note about the type of scan: MRI is not commonly used to evaluate the parathyroids, and it is not one that I would order. The most common study is a sestamibi scan, a nuclear medicine test. Ultrasound and CT are also common. Finally, in rare cases a PET scan can be done. If your doctor is starting with an MRI, it may mean that they do not have a lot of experience in dealing with parathyroid disease.