Common Conditions

Thyroid: Overview

This is an information sheet which advises you of the pros and cons of having your thyroid gland removed and answers to common worries that patients have. It is not intended to replace a consultation nor is it intended to be a textbook of surgery.

The thyroid gland lies in the neck and makes thyroxine which is a very important hormone. If too little thyroxine is present, children's growth and development are retarded and adults become slow, depressed, fat and constipated (myxoedema). If too, much thyroxine is secreted, patients become over-active, thin, ravenously hungry and find difficulty in sleeping (thyrotoxicosis). Elderly patients with thyrotoxicosis may develop heart problems, causing palpitations. Small thyroids may be under-active, as may be lumpy or large glands.

There are two common problems in diagnosis:

• Is the gland under or over active?
• If enlarged or nodular, what is it made of?

Enlargement or malfunctions of the thyroid can be diagnosed by clinical examination and appropriate tests. These include blood tests of function, fine needle aspiration biopsy (FNAB), ultrasound examination and, occasionally, computerized tomography (CT) scanning or scanning with radioactive iodine. FNAB is a technique to study the cells in a thyroid swelling by removing a minute sample, using a very fine needle. It is very similar to having a blood test or an injection.

Operation is particularly indicated in patients with nodules that are considered to be at risk of malignancy and in some patients with an over-active thyroid where the gland is very large. In these days, the operation is less frequently carried out for young thyrotoxic patients but, even here, patients with enlargement may be eligible for surgical treatment. Some patients prefer surgery to radioactive iodine treatment, even though that treatment has an excellent record of success and safety. Patients who have experienced radiation of the neck in the distant past may develop a nodularity of the gland and this is best treated by surgery, particularly as there is some increased frequency of malignancy in these irradiated glands. A few patients develop very large thyroid glands to the extent that there is pressure on the oesophagus (swallowing tube) or trachea (windpipe). This can lead to a sense of difficulty in swallowing or a feeling that breathing is being restricted. The effects of these large swellings can he shown on a chest X-ray or a body scan when the windpipe may be seen to be deviated and/or squashed by the enlarged gland. In this situation, surgery is necessary and effective.

Most thyroidectomies are undertaken without problems. Less than one in 20 of patients suffer any complications. Immediately after surgery, the patient may experience some local swelling, a sore throat, some difficulty in swallowing and some discomfort in the back of the neck. This is all due to the manipulation of the operation but these symptoms are usually short-lived and should disappear spontaneously. The common complications associated with removal of the thyroid are wound infection, blood or fluid collecting at the repair site (haematoma or seroma), numbness of the skin or even persistent pain at the site of the repair. These are relatively minor complications which are usually dealt with by a course of antibiotics or drainage of the wound. As a rule, the incision heals very well and is cosmetically acceptable. Some undue thickening (keloid) can occur in patients of oriental or black origin or in adolescence and, in those patients, full maturation of the wound may take 2 or 3 years.

On rare occasions more serious complications may occur. Sometimes, there is some derangement of the voice after operation. This is due to the irritation of the anaesthetic tube and manipulation of the operation and it is usually temporary but, occasionally, because of the surgical dissection, one of the delicate laryngeal nerves will stop working. This will cause hoarseness and weakness of the voice which will almost always recover within 2 or 3 months. Rarely, damage to the laryngeal nerves is permanent, particularly in operations carried out for malignancy and, occasionally, we discover that patients have pre-existing voice problems, of which they were sometimes unaware. When most of the thyroid gland has been removed, a reduction in blood calcium may follow (associated parathyrold upset). Again, in most patients, this is temporary. If blood calcium falls to very low levels, the patient may develop tingling around the mouth and in the fingers and toes, with some muscle spasms. This can easily be relieved by treatment with calcium, either orally or by injection. It is important not to make this worse by over- breathing. Calcium levels return to normal within a few months and regular blood tests can document this change. Occasionally, pills must be taken on a permanent basis. The surgical techniques used these days make these eventualities unlikely.

On balance, the risks of not treating your thyroid outweigh the risks of surgery and you have been recommended to have the thyroid (or part of it) removed. Closer to the date of your operation, you will receive an appointment for a pre-operative visit to the hospital. You will receive further details of the operation and pre-operative preparations then, and will have the opportunity to ask any questions. However, if you have any worries that cannot wait until then, please make an appointment for my Out-patient Clinic at the hospital.