Evaluating Thyroid Problems
Your doctor suspects that you have a thyroid problem. Thyroid problems can be fairly easy to diagnose. Your doctor is likely to take a medical history, do a physical exam, and order blood tests. You may also have further testing. Based on the results, your doctor may refer you to an endocrinologist (thyroid specialist) or a surgeon.
Your doctor will ask about symptoms you’ve noticed, such as changes in body temperature, weight, and energy level. Tell your doctor about all medications you’re taking and if you’ve ever had thyroid surgery. Be sure to mention if you have a family history of thyroid problems, or if you are pregnant or plan to become pregnant. Also tell your doctor if you’ve ever been treated with radiation to the head or neck.
After the medical history, your doctor will examine you. He or she will feel your neck to check your thyroid gland for changes in size or shape. Your doctor may also look for changes in heart rate, reflexes, muscle strength, or skin texture.
Your doctor will order blood tests. They may include the following:
A TSH test helps determine how much thyroid stimulating hormone (TSH) is being produced by the pituitary gland. This test is used to help diagnose or evaluate most thyroid problems, by determining whether a person's thyroid hormone is normal, overactive (hyperthyroidism), or underactive (hypothyroidism).
T3 and T4 tests help determine how much thyroid hormones (T3 and T4) are available in the blood. This test if often used to help diagnose hyperthyroidism or hypothyroidism.
Other diagnostic tests
Based on the results of your exam and blood tests, you may have other diagnostic tests. They may include the following:
Thyroid antibody tests are blood tests that look for problems with the immune system. These tests are most often used if hypothyroidism or hyperthyroidism is suspected.
An ultrasound uses sound waves to create an image showing the size and shape of the thyroid gland. It is most often used if a nodule (a lump in the thyroid) or goiter (enlarged thyroid) is suspected.
A radioactive iodine uptake test measures how much iodine the thyroid gland takes in. It is most often used if hyperthyroidism is suspected.
A thyroid scan is an imaging test that can show if part of the thyroid gland is making too much thyroid hormone. It is most often used if hyperthyroidism is suspected.
Fine needle aspiration (FNA)
If you have a nodule, you may have a fine needle aspiration done. This is a biopsy, which is a procedure to remove a sample of cells. An FNA is the best test to find out if thyroid cells are cancerous. The doctor uses a needle to take cells from the thyroid. The cells are then analyzed under a microscope. If cancer is suspected, other tests may also be done to help determine the type of cancer.
Risks and complications of FNA are rare, but include mild discomfort, bleeding, and skin infection.