Does a needle biopsy of thyroid hurt ? does it take long?

Minimal discomfort: A fine needle aspiration biopsy of the thyroid is done with a fine gauge needle (usually 22 to 25 gauge). For comparison, when blood is drawn one usually uses an 18 gauge needle (lower gauge means larger needle). Usually local anesthesia is used so there should be very little discomfort. The actual biopsy only takes a few seconds for each needle pass (typically 4 passes are done).