Definition of Parathyroid biopsy:

A parathyroid biopsy is the removal of a small piece of a parathyroid gland for examination under a microscope. The parathyroid glands are found just behind the thyroid gland on each side of the neck.

See also:

• Hyperparathyroidism
• Parathyroid adenoma
• Parathyroid hyperplasia

How the test is performed:

There are two parathyroid glands on either side of the neck, making a total of four glands. The parathyroid glands cannot be felt with the hands.

A parathyroid biopsy is done while you are awake. Using an ultrasound machine, the health care provider locates the gland that is of concern. A thin needle is inserted directly into the gland, and a small piece of tissue is removed. The procedure takes 10 - 30 minutes.

The tissue is sent to a laboratory, where it is examined under a microscope. The levels of parathyroid hormone (PTH) in your blood will also be checked.

How to prepare for the test:

Tell your health care provider if you have any drug allergies or bleeding problems, or if you are pregnant.

Make sure the health care provider knows about all the medications you are taking. Tell your health care provider if you are taking any blood thinning medications (aspirin, heparin, Lovenox), because you may have to stop taking them a few days before the procedure.

You must sign a consent form.

How the test will feel:

The test feels like a quick needle jab or stick. You may feel a sting as the needle is inserted into the gland. Most people do not need any pain medication.

Why the test is performed:

The parathyroid glands release parathyroid hormone (PTH). This hormone controls the level of calcium in the body.

This procedure is most often done to rule out cancer as a cause of high parathyroid hormone levels.

It may also be done if an ultrasound exam shows a larger-than-normal parathyroid gland.