The thyroid gland is the biggest gland in the neck. It is situated in the anterior (front) neck below the skin and muscle layers. The thyroid gland takes the shape of a butterfly with the two wings being represented by the left and right thyroid lobes which wrap around the trachea. The sole function of the thyroid is to make thyroid hormone. This hormone has an effect on nearly all tissues of the body where it increases cellular activity. The function of the thyroid therefore is to regulate the body's metabolism.
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Common Thyroid Problems

The thyroid gland is prone to several very distinct problems, some of which are extremely common. These problems can be broken down into [1] those concerning the production of hormone (too much, or too little), [2] those due to increased growth of the thyroid causing compression of important neck structures or simply appearing as a mass in the neck, [3] the formation of nodules or lumps within the thyroid which are worrisome for the presence of thyroid cancer, and [4] those which are cancerous. Each thyroid topic is addressed separately and illustrated with actual patient x-rays and pictures to make them easier to understand. The information on this web site is arranged to give you more detailed and complex information as you read further.



Goiters ~ A thyroid goiter is a dramatic enlargement of the thyroid gland. Goiters are often removed because of cosmetic reasons or, more commonly, because they compress other vital structures of the neck including the trachea and the esophagus making breathing and swallowing difficult. Sometimes goiters will actually grow into the chest where they can cause trouble as well. Several nice x-rays will help explain all types of thyroid goiter problems.

Thyroid Cancer ~ Thyroid cancer is a fairly common malignancy, however, the vast majority have excellent long term survival. We now include a separate page on the characteristics of each type of thyroid cancer and its typical treatment, follow-up, and prognosis. Over 30 pages thyroid cancer.


Solitary Thyroid Nodules ~ There are several characteristics of solitary nodules of the thyroid which make them suspicious for malignancy. Although as many as 50% of the population will have a nodule somewhere in their thyroid, the overwhelming majority of these are benign. Occasionally, thyroid nodules can take on characteristics of malignancy and require either a needle biopsy or surgical excision. Now includes risks of radiation exposure and the role of Needle Biopsy for evaluating a thyroid nodule. Also a new page on the role of ultrasound in diagnosing thyroid nodules and masses.

Hyperthyroidism ~ Hyperthyroidism means too much thyroid hormone. Current methods used for treating a hyperthyroid patient are radioactive iodine, anti-thyroid drugs, or surgery. Each method has advantages and disadvantages and is selected for individual patients. Many times the situation will suggest that all three methods are appropriate, while other circumstances will dictate a single best therapeutic option. Surgery is the least common treatment selected for hyperthyroidism. The different causes of hyperthyroidism are covered in detail.


Hypothyroidism ~ Hypothyroidism means too little thyroid hormone and is a common problem. In fact, hypothyroidism is often present for a number of years before it is recognized and treated. There are several common causes, each of which are covered in detail. Hypothyroidism can even be associated with pregnancy. Treatment for all types of hypothyroidism is usually straightforward.


Thyroiditis ~ Thyroiditis is an inflammatory process ongoing within the thyroid gland. Thyroiditis can present with a number of symptoms such as fever and pain, but it can also present as subtle findings of hypo or hyper-thyroidism. There are a number of causes, some more common than others. Each is covered on this site.
 

Thyroid Operations

Several Surgical Options for the Thyroid Gland Depending on the Problem

Which operation is performed on a thyroid gland depends upon 2 major factors. The first is the thyroid disease present which is necessitating the operation. The second is the anatomy of the thyroid gland itself as is illustrated below.

If a dominant solitary nodule is present in a single lobe, then removal of that lobe is the preferred operation (if an operation is even warranted). If a massive goiter is compressing the trachea and esophagus, the the goal of surgery will be to remove the mass and usually this means a sub-total or total thyroidectomy (occasionally a lobectomy will suffice). If a hot nodule is producing too much hormone resulting in hyperthyroidism, then removal of the lobe which harbors the hot nodule is all that is needed.

Most surgeons and endocrinologists recommend total or near total thyroidectomy in virtually all cases of thyroid carcinoma. In some patients with papillary carcinomas of small size, a less aggressive approach may be taken (lobectomy with removal of the isthmus). A lymph node dissection within the anterior and lateral neck is indicated in patients with well differentiated (papillary or follicular) thyroid cancer if the lymph nodes can be palpated. This is a more extensive operation than is needed in the majority of thyroid cancer patients. All patients with medullary carcinoma of the thyroid require total thyroidectomy and aggressive lymph node dissection.


Surgical Options


Partial Thyroid Lobectomy. This operation is not performed very often because there are not many conditions which will allow this limited approach. Additionally, a benign lesion must be ideally located in the upper or lower portion of one lobe for this operation to be a choice. One example is shown on our hyperthyroid treatments page.


Thyroid Lobectomy. This is typically the "smallest" operation performed on the thyroid gland. It is performed for solitary dominant nodules which are worrisome for cancer or those which are indeterminate following fine needle biopsy. Also appropriate for follicular adenomas, solitary hot or cold nodules, or goiters which are isolated to one lobe (not common).


Thyroid Lobectomy with Isthmusectomy. This simply means removal of a thyroid lobe and the isthmus (the part that connects the two lobes). This removes more thyroid tissue than a simple lobectomy, and is used when a larger margin of tissue is needed to assure that the "problem" has been removed. Appropriate for those indications listed under thyroid lobectomy as well as for Hurthle cell tumors, and some very small and non-aggressive thyroid cancers.


Subtotal Thyroidectomy. Just as the name implies, this operation removes all the "problem" side of the gland as well as the isthmus and the majority of the opposite lobe. This operation is typical for small, non-aggressive thyroid cancers. Also a common operation for goiters which are causing problems in the neck or even those which extend into the chest (substernal goiters).

Total Thyroidectomy. This operation is designed to remove all of the thyroid gland. It is the operation of choice for all thyroid cancers which are not small and non-aggressive in young patients. Many (most?) surgeons prefer this complete removal of thyroid tissue for all thyroid cancers regardless of the type.

Surgical Technique

The standard neck incision is made typically measuring about 4-5 inches in length although many endocrine surgeons are now performing this operation through an incision as small as 3 inches in thin patients. This incision is made in the lower part of the central neck and usually heals very well. It is almost unheard of to have an infection or other problem with this wound. The surgeon will then typically remove the part of the thyroid which contains the "problem". As mentioned above, for thyroid cancer, this will usually entail all of the thyroid lobe which harbors the malignancy, the isthmus, and a variable amount of the opposite lobe (ranging from 0 to 100% depending on the size and aggressive nature of the cancer, the cancer type, and the experience of the surgeon). The surgeon must be careful of the recurrent laryngeal nerves which are very close to the back side of the thyroid and are responsible for movement of the vocal cords. Damage to this nerve will cause hoarseness of the voice which is usually temporary but can be permanent. This is an uncommon complication (about 1 to 2 percent), but it gets lots of press because it is serious. The surgeon must also be careful to identify the parathyroid glands so their blood supply can be maintained. Another potential complication of thyroid surgery (although VERY RARE) is hypoparathyroidism which is due to damage to all four parathyroid glands. Usually the only thyroid operations which have even a slight chance of this complication is the total or subtotal thyroidectomy. Although these complications can be serious, their risk should not be the sole determinant of whether or not to undergo surgery.

The relationship of the thyroid gland to the voice box and parathyroid glands can be seen here quite clearly. Remember that they share the same blood supply, so the surgeon must take care to preserve the parathyroid artery and vein while ligating the vessels to the thyroid gland itself. This is usually not a problem, but sometimes it is not possible to save them all. In this case, the surgeon will usually implant the parathyroid gland into a muscle in the neck. The parathyroid will grow there and function normally...its not a big deal, and you'll never know the difference.

Often formal surgery is not needed to determine if a thyroid mass is cancerous. Because these masses can often be felt, a physician can stick a small needle into it to sample cells for malignancy. This is called Fine Needle Aspiration Biopsy (FNA) and is covered in detail on another page which also covers the potential of thyroid masses to be malignant in much greater detail.