Thyroid Illness

The thyroid is a small gland, shaped like a butterfly. It sits in the middle of the lower neck just below the "Adam's Apple." The function of the thyroid is to control the body’s metabolism (rate at which cells perform their duties). To control metabolism, the thyroid produces "thyroid hormones," called T4 and T3. These direct the body’s cells in the use of energy.The gland also produces "calcitonin," that helps to regulate calcium levels in the blood.

When the thyroid is functioning properly, it will maintain the right amount of hormones within the body. The quantity of thyroid hormones in the bloodstream is monitored and controlled by the pituitary gland. The pituitary gland, which is located in the center of the skull below the brain, senses if thyroid hormones levels are high or low and then adjusts its own hormone (TSH, or thyroid stimulating hormone) to tell the thyroid what to do.

When the thyroid produces too much hormone, the body uses energy faster than it should, producing a condition called "hyperthyroidism." When the thyroid doesn't produce enough hormone, the body uses energy slower than it should, ("hypothyroidism"). There are many different reasons why either of these conditions might develop. Currently, about 20 million Americans have some form of thyroid disease with women five to eight times more likely than men to have these problems. Producing Hypothyroidism are: Thyroiditis (an inflammation of the thyroid gland) Hashimoto’s thyroiditis (a painless, hereditary autoimmune disease) Iodine deficiency (Iodine is used by the thyroid to produce hormones. Iodine deficiency occurs in the third world but has been virtually wiped out by the use of iodized salt in developed countries.) Treatment of Hyperthyroidism (chemical or surgical ablation off the overactive gland may destroy most or all function).

Producing Hyperthyroidism are:

• Graves’ disease (the entire thyroid gland is overactive and makes too much hormone. Also called "diffuse toxic goiter.")
• Nodules (growths within the thyroid may be overactive. A single nodule is called "toxic thyroid nodule," several nodules are called "toxic multi-nodular goiter.")
• Thyroiditis (can release hormones stored in the thyroid gland causing hyperthyroidism for a few weeks or months).

Symptoms

The symptoms of under and over-active thyroids make sense, given what we have said above regarding the thyroid's direction of energy use.

Hypothyroidism- Fatigue; forgetfulness; weight gain; dry, coarse skin and hair; hoarse voice cold intolerance

Hyperthyroidism- Nervousness; weakness/tremors; weight loss; sleep disturbance; vision problems/eye irritation; heat sensitivity

Treatment

Hypothyroidism is treated with synthetic hormone replacement in pill form (levothyroxine).

Hyperthyroidism is more difficult to treat. Therapy could involve use of drugs to block hormone production, radioactive iodine treatment to disable the thyroid, or even thyroid surgery to remove part or the entire gland. The most popular treatment is radioactive iodine which often results in hypothyroidism and the need for synthetic hormone replacement (as noted above).

Thyroid Nodules

The head and neck surgeon is commonly consulted to evaluate and possibly treat thyroid nodules. These are small lumps within the gland that may become large enough to be palpable on physical examination of the neck. A number of different things may present as a "lump" in the thyroid gland:

• Colloid nodule (most common—these are benign overgrowths of normal thyroid tissue).
• Follicular adenoma (also is benign mass).
• Thyroid cyst (fluid-filled areas of the thyroid, some are entirely fluid-filled while others called "complex cysts," also have solid components. Fluid-filled cysts are usually benign, but complex cysts are sometimes malignant).
• Inflammatory nodule (occasionally develops as a result of chronic inflammation of the thyroid).
• Multinodular goiter (Goiter describes any enlargement of the thyroid. One of several factors that can produce goiter is the presence of multiple nodules.
• Toxic adenoma (a glandular mass that produces thyroid hormone ignoring the control of the pituitary).
• Thyroid cancer

Diagnosis

The doctor will want to measure the level of T3 and T4 in the blood, as well as the amount of thyroid stimulating hormone (TSH) coming from the pituitary. Using these tests, it may be determined if the patient is hypo- or hyper thyroid. Ultrasound uses sound waves to characterize the nodule and can usually distinguish between a cystic and a solid mass. Also, ultrasound can sometimes guide the doctor as he attempts to sample nodular tissue using a technique called "fine needle aspiration," (FNA).

In this technique, the tissues over the thyroid are numbed with local anesthetic, and the surgeon passes a very fine needle into the nodule(s) to remove cellular samples. These can be examined by the pathologist to distinguish benign from malignant tissues. When the sample produces uncertain results, surgical removal of the nodule or the thyroid lobe that contains it may be recommended.

The surgeon may recommend a thyroid scan to help evaluate a nodule.In this test, radioactive iodine is injected into a vein and travels to the thyroid where it is concentrated. A special camera then produces an image of the thyroid on a computer screen. Nodules that produce excess hormone are called "hot" nodules because they show up as areas of concentrated isotope. "Warm" nodules look and function like normal tissue, while "cold" nodules are nonfunctioning and appear as defects or holes in the scan.

Hot nodules are almost always benign, but a small percentage of warm or cold nodules are malignant. Unfortunately, thyroid scan can't distinguish between benign and malignant warm and cold nodules.

Treatment

Benign nodules that are not overproducing hormone require no treatment except if their number and volume begin to make the patient symptomatic, (e.g. interfering with swallowing or breathing).When such is the case, thyroid lobectomy or sub-total thyroidectomy may be indicated.

The usual treatment for malignant nodules is surgical removal, often along with the majority of thyroid tissue ( see thyroid cancer). Nodules diagnosed as indeterminate or suspicious by FNA biopsy also must be surgically removed so that they can be examined more thoroughly for signs of cancer. Nodules that over-produce hormone may be treated with thyroid hormone suppression therapy, although it is not clear that this helps. Radioactive iodine will cause functioning nodules to shrink, but often leads over time to hypothyroidism.

If a solitary nodule is overproducing hormone, surgical removal of the thyroid lobe containing the mass can produce prompt resolution of the problem. Risks of thyroid surgery include damage to the nerve that controls the vocal cords and damage to the parathyroid glands (tiny glands located on the back of the thyroid gland that help control the level of calcium in the blood).