The thyroid gland is a butterfly shaped organ that wraps around the trachea (windpipe). It lies just below the thyroid cartilage (Adam’s apple). The gland produces thyroid hormone that has a role in regulating the body’s metabolism. In many cases the symptoms of too much or too little thyroid hormone do not point specifically to a thyroid disorder. Symptoms can include changes in heart rate, feeling excessively hot or cold or changes in body weight. Blood tests can accurately determine thyroid function.
Common reasons for considering Thyroid Surgery
Goitre refers to the enlargement of the thyroid gland and is one of the most common reasons for thyroid surgery. The enlargement of the thyroid is most commonly due to multiple nodules within the thyroid. This condition is called a multinodular goitre. A large thyroid gland can apply pressure to the surrounding organs, particularly to the trachea (windpipe) or the oesophagus. This can lead to symptoms such as difficulty with breathing or swallowing. An enlarged thyroid gland may also be easily visible in the neck and can be removed for cosmetic reasons.
Nodules or lumps in the thyroid are very common and increase in incidence with age. In fact approximately 50% of the population aged over 50 years will have at least one thyroid nodule. They may be found either by palpation (feeling the neck) or seen when imaging the neck (such as via an ultrasound, CT or MRI scan of the neck performed for other reasons). Most thyroid nodules are small and do not require any further investigation. Where further tests are suggested a needle biopsy is usually performed (often with the guidance of ultrasound). Surgery may be recommended if the results of a needle biopsy are not benign; if the nodule is particularly large;or if the ultrasound shows that the nodule has an appearance suggestive of thyroid cancer.
In most cases hyperthyroidism (due to an overactive thyroid) can be treated successfully with medication or by ablating the thyroid with radioactive iodine. For some patients however, surgery of the thyroid is the preferred treatment for hyperthyroidism.
Thyroid cancer is becoming more common. Most patients with thyroid cancer initially notice a nodule or lump in the thyroid. The most common type of thyroid cancer is papillary thyroid cancer. Treatment for this involves removal of the thyroid (total thyroidectomy). Often some lymph nodes in the neck will also be removed at the time of thyroid surgery. Many patients are also treated with radioactive iodine. Cure rates are very high for most patients with thyroid cancer.
The two most common operations on the thyroid are removal of the whole gland (total thyroidectomy); or of one of the lobes of the thyroid gland (either right or left hemithyroidectomy). Thyroid surgery is almost always performed under general anaesthetic. An incision is made in the neck usually 2-3cm above the collarbone. Most patients stay in hospital for 1-2 nights after thyroid surgery.
All patients who undergo total thyroidectomy and up to 20% of those who undergo hemithyroidectomy will require thyroid hormone replacement. Thyroxine is a tablet used to replace thyroid hormone. It is taken once a day for the rest of your life and usually well tolerated. All patients who undergo total thyroidectomy will be placed on thyroxine after surgery and thyroid function is checked by a blood test 6 weeks after surgery.
Risks of Thyroid Surgery
Although small, there are some risks of having thyroid surgery. These can include:
- Voice changes
The nerves that supply the vocal cords run closely adjacent to the thyroid. Great care is taken during surgery to ensure that these nerves are not damaged. It is not uncommon to have a slightly hoarse or weak voice after thyroid surgery. This is often due to swelling and not nerve damage and your voice will almost always recover over weeks to months after surgery. Long-term major voice changes are uncommon and occur in less than 1% of patients who undergo thyroid surgery. The movement of your vocal cords will usually be checked both before and after your surgery with a flexible telescope inserted through the nose (nasendoscopy). In most cases Chris will perform this procedure when you see her before the surgery and again at your post-operative visit.
- Low calcium levels (hypoparathyroidism)
The parathyroid glands are tiny, delicate glands (about the size of a grain of rice) that lie adjacent to (and sometimes within) the thyroid gland. There are usually four parathyroid glands, two on each side of the neck. Great care is taken to preserve these glands during surgery but they can be “stunned” for a period of time after surgery. After total thyroidectomy all will have their calcium levels and parathyroid function checked prior to leaving hospital. Symptoms of low calcium including tingling around the mouth, in the fingers or toes. Approximately 20% of patients will require tablets (caltrate with or without calcitriol) to boost the calcium level after total thyroidectomy. Patients are almost always weaned off these over the weeks following surgery and less than 1% of patients who undergo total thyroidectomy require long-term calcium supplements.
The thyroid gland has a very rich blood supply. Bleeding after thyroid surgery is very uncommon (occurs in fewer than 1% of patients). Occasionally patients may require a second operation if bleeding is significant.
- Wound healing problems (scarring, infection)
It is necessary to make an incision in the neck to remove the thyroid. In most patients the scar will heal to a thin line over a period of months after thyroid surgery. Everyone heals slightly differently and some people are prone to red and raised scars (hypertrophic or keloid scars). Many scars will continue to improve over the six to eighteen months after surgery.
In addition to these risks that are specific to thyroid surgery any operation with a general anaesthetic is associated with risks to your health. Serious complications in healthy patients are extremely rare. Potential problems can include:
- Heart problems (heart attack, stroke, death)
- Lung problems (pneumonia)
- Blood clots (clots in the legs or lungs)
- Drug reactions
It is important that you tell Dr O’Neill and your anaesthetist if you have any other medical conditions or take any regular medications prior to your surgery.
Other helpful websites
- Australian and New Zealand Endocrine Surgeons
- American Association of Endocrine Surgeons Patient Information Site
- NSW Cancer Council (information on thyroid cancer)