A parathyroid biopsy is a procedure to remove a small piece of a parathyroid gland. The parathyroid glands are the four glands behind the thyroid in the neck.

This procedure is most often done to confirm the cause of hyperparathyroidism.

It may also be done if an ultrasound exam shows a larger than normal parathyroid gland. Your doctor can only see a parathyroid gland on ultrasound if it is abnormally swollen.

A parathyroid biopsy is done while the patient is awake. Using an ultrasound machine, the health care provider locates the gland of concern. A thin needle is inserted directly into the gland, and a small piece of tissue is removed.

The tissue is sent to a laboratory, where it is examined under a microscope. The tissue's levels of parathyroid hormone (PTH) will also be checked. PTH is secreted by the parathyroid glands and helps control the body's calcium levels.

Tell your health care provider if you have any drug allergies or bleeding problems, or if you are pregnant. You must sign a consent form. Also, make sure the health care provider knows about all the medications you are taking.

The test feels like a quick shot (injection). You may feel a sting as the needle is inserted into the gland.