HF 6368

Fine Needle Aspiration of a Thyroid Nodule Using Ultrasound

A fine needle aspiration (FNA) or biopsy of a thyroid nodule is a simple test to check a thyroid nodule or mass for cancer cells. A very fine, small needle is used to remove fluid and cells from the nodule or mass. The fluid and cells are then sent to the lab for review. A thyroid biopsy is safe and rarely results in complications.

Before Your Thyroid FNA

You can eat normally before your biopsy. After you arrive, the doctor will explain what will happen and answer any questions. You will be asked to sign a consent form.

During Your Thyroid FNA

You will lie on a table with a pillow under your neck. An ultrasound (a machine that sends sound waves through the skin and creates images on a TV screen) is used to look at the site of the nodule or mass.

A clear jelly is put on your neck and an ultrasound probe is used to look for nodules. If a nodule(s) is found, your neck will be cleaned with special soap. Then, a numbing medicine is used to help prevent pain.

A fine needle is passed 3 to 6 times into the nodule or mass so that enough cells are removed.

The biopsy can take anywhere from 60-90 minutes. It will depend on how many nodules are biopsied. The biopsy results are sent to your doctor within 5 days. Although the test is not perfect, a biopsy should give enough information for your doctor to decide your course of treatment.

After the Biopsy

You may feel mild discomfort during the procedure. After the numbing medicine wears off, you may be sore for 1-2 days. We suggest using Tylenol for soreness. A small amount of bruising is also common.


You can return home or go back to work after the biopsy. You may resume your normal routine after the test with no restrictions.

When to Call

  • You feel dizzy, faint or lightheaded.

  • Your pain around the site gets worse rather than better 2-3 days later.

  • You do not feel well and have a fever over 100.4° F (38° C).

  • You develop redness and swelling around the site.

Who to Call

University Hospital

Monday – Friday, 7:30 am – 4:30 pm

  • Ultrasound (608) 262-5279

  • Nurse (608) 422-8182

  • Toll-free (800) 323-8942

East Madison Hospital

Monday – Friday, 8 am – 5 pm
(608) 242-2888

After hours, weekends and holidays, you will reach the paging operator. Ask to speak to the resident on call for Endocrinology. Leave your name and phone number with the area code. The doctor will call you back.