Thyroid

David R. Hotelling, MD, FACE, Thyroid Specialist

The thyroid is an H-shaped gland located in the front of the neck below the voice box.  It produces two hormones that help regulate energy and metabolism (which includes growth and development).  They are called T4 and T3.  They, in turn, are regulated by a pituitary hormone called thyroid stimulating hormone (TSH).  The pituitary is a tiny gland located at the base of the brain.

There are several problems that can occur when the thyroid malfunctions.  However, the most common are hyperthyroidism (overproduction of thyroid hormone), hypothyroidism (underproduction of thyroid hormone) and thyroid nodules.

Hyperthyroidism is an autoimmune disease that occurs when the thyroid inappropriately produces too much thyroid hormone.  This can be caused by overproduction of hormone by the entire gland (Grave’s Disease), multiple or single nodules which produce too much thyroid hormone, or thyroid inflammation.  Symptoms of hyperthyroidism include anxiousness, weight loss, feeling of warmth and perspiring, palpitations, rapid and irregular heartbeats, frequent bowel movements, irregular periods, tremor of the hands and feelings of weakness.

Hyperthyroidism is treated with medications to slow down thyroid function (methimazole, tapazole or PTU).  It also can be treated with radioactive iodine – which is taken orally in a single dose and concentrates mostly in the thyroid.  Radioactive iodine damages thyroid cells so that overproduction of hormone decreases.  However, this often causes permanent hypothyroidism – which can be corrected by taking thyroid hormone.  Surgery is another option, although not often utilized in this country.

Hypothyroidism occurs when the thyroid does not make enough thyroid hormone.  This is also felt to be an autoimmune disease that is called chronic autoimmune thyroiditis (Hashimoto’s Disease).  Symptoms can vary considerably.  Some people have no symptoms.  Most people will eventually develop increased fatigue, dry skin, thinning hair and eyebrows, feelings of cold, menstrual irregularities, exertional shortness of breath and constipation.  Hypothyroidism can also cause mild high blood pressure and elevated cholesterol levels.

Treatment of hypothyroidism is simple – replace thyroid hormone.  This means taking one pill/day – usually indefinitely.  Medication is called levothyroxin (generic) and brand name (synthroid, levoxyl, levothroid, euthyroid).  These medications are all equally effective but it is preferable to stay within a single brand name over time as bioavailabilty between brands can differ somewhat.  It is currently felt to be preferable not to use generic levothyroxin if possible because bioavailability from batch to batch can sometimes vary.

Thyroid specialist David R. Hotelling, MD, notes: “The good news is that people can live completely normal lives and have normal longevity without complications if they are treated appropriately for either hyper- or hypothyroidism.”

Thyroid nodules
Nodules in the thyroid are very common – in fact they are present in about 50% of the population.  They are often detected by a healthcare provider as part of a physical examination, and often people themselves note a “bump”.  They are sometimes incidentally found on x-rays performed on the neck area for other reasons.  Ninety-five percent of thyroid nodules are benign and are of no significant consequence.  However, once found, it is important to determine if the nodule could be cancerous.

Diagnostic procedures include measuring thyroid hormone levels, to check if the nodule is actually making thyroid hormone inappropriately or if nodules are part of an autoimmune process called “Hashimoto’s” which may cause an increased risk for developing hypothyroidism.

Thyroid ultrasound provides the best and most accurate information about thyroid gland structure and anatomy – including nodules.  A thyroid scan can also be performed using radioactive iodine or technetium.  This procedure helps identify a nodule that may be actually making too much hormone (about 5% of the time).  Most nodules do not assimilate iodine and therefore are “cold” on scan.  However, a TSH blood test can identify nodules that are producing too much hormone, and thyroid ultrasound alone is better at defining nodule size and shape.  Once the nodule is found, and if greater than 1 cm, thyroid biopsy is recommended.  This is a fine needle aspiration biopsy and is usually performed with ultrasound guidance – using a very thin needle that is placed in the nodule to aspirate small amounts of tissue sample.  The sample is then sent to pathology and results return in several days.  This procedure can be performed in the office as an outpatient and takes very little time.

Most of the time (95%) nodules are benign.  When the pathology returns with a finding of “suspicious or atypical” then we suggest that the nodule may already represent significant cancer or has atypical qualities that could progress to cancer.  It is usually recommended that the nodule be surgically removed at this point for a more definitive diagnosis of true cancer (about 20-30%).  Fortunately, even if thyroid cancer is found, the treatment is relatively straightforward (surgical removal of thyroid followed by oral radioactive iodine) and long-term prognosis is excellent for complete cure and long-term survival.

We are able to perform thyroid nodule biopsies right in our office, which is convenient and saves time and expense.

Thyroid and parathyroid ultrasound are both available in our office, for your convenience.

For more information regarding thyroid disease please see following websites:
• The American Thyroid Association (www.thyroid.org)
• Thyroid Foundation of America (www.allthyroid.org)
• National Library of Medicine (www.nlm.nih.gov/medlineplus/thyroiddiseases.html)

  • Thyroid and parathyroid ultrasound are available in our office, for your convenience.

• Office location: 477 Congress Street (the Time & Temperature Building), 5th floor, Portland, Maine 04101

• Parking: Free parking is available in our garage, reached from Cumberland Ave.

• Telephone: 207-773-6463

• Fax: 207-828-4587

Thyroid and parathyroid ultrasound are available in our office, for your convenience.
David R. Hotelling, MD, FACE, is on the medical staff at Maine Medical Center and is a consulting staff member at Mercy Hospital. Dr. Hotelling is board-certified and completed a fellowship in endocrinology at Beth Israel Hospital in Boston, a Harvard affiliate.