What is the thyroid gland?
The thyroid is a gland found on the front, mid-lower part of the neck. It is butterfly shaped and consists of a right and left lobe joined together by the isthmus in the middle. It excretes a hormone called thyroxine which is very important for human metabolism. At certain points on the thyroid gland you can find four other smaller glands called the parathyroids. They excrete a hormone called parathormone that controls calcium levels in the blood.
Why should I need a thyroid operation?
There are three reasons for having a thyroid operation:
- The appearance of an isolated lump (node) in the gland with a possibility of this being cancerous. The only certain way of confirming or excluding this is through a thyroidectomy, either partial or total. If cancer is diagnosed on histological testing and depending on the type of cancer then further treatment might be necessary.
- A diffuse enlargement of the gland (soft or multinodular). This can cause:
a) Pressure symptoms on the windpipe and gullet with breathing and swallowing difficulties.
b) Suspicion of thyroid cancer
c) Unsightly appearance of the neck.
3. Hyperthyroidism that is resistant to treatment with medicine.
Will I need thyroxine replacement after the operation?
The thyroid gland has adequate reserves for production and excretion of thyroxine. Even after removing half of the gland (hemithyroidectomy) the need for thyroxine replacement is rare. This is usually only necessary when the whole of the gland is removed (total thyroidectomy).
What tests are needed before the operation?
- A blood test to check the levels of thyroid hormones and calcium and detect possible thyroid antibodies.
- Fine Needle Aspiration (FNA) of the lump that can help to come to a diagnosis.
- Ultrasound of the thyroid
How is the operation done?
The operation is done under a general anaesthetic. A horizontal incision approximately 5-6 cms is done low in the midline of the neck over the thyroid. For partial or hemithyroidecomy only have of the gland is removed (left or right lobe) whereas for total thyroidectomy the whole of the gland is removed. At the end of the operation a temporary drainage tube is placed through the wound and the wound is closed with absorbable sutures.
The blood calcium levels are checked a few hours after the operation and the day after. The patient can go home 24-48 hours after the operation.
What are the possible complications?
In most cases the operation is complication free. However, every operation carries some risks such as infection, bleeding and anaesthetic related problems. Less commonly the following complications can take place:
Scar: The operation wound usually heals almost completely a year after. Occasionally, it can leave a scar behind depending on the skin healing ability and its tendency to scar.
Hoarse voice: There are usually no voice changes after the operation. Nevertheless, the nerves that control movement of the vocal cords run immediately behind the thyroid (one each side). Therefore, there is always a risk of damaging those nerves during the operation which is around 1%. If only one of the nerves is damaged then hoarseness usually improves with time. If however there is damage to both nerves (after total thyroidectomy) then both vocal cords become immobile that can cause breathing problems.. This is thankfully rare.
Calcium problems: The parathyroid glands control the blood levels of calcium and as mentioned above are found adjacent to the thyroid gland. Sometimes, the parathyroids stop working after the operation. This is usually temporary and can cause low levels of calcium in the blood with symptoms such as tingling on the fingers, feet and lips. Calcium supplements and vitamin D will be necessary usually for a short period of time.
Thyroxine replacement: After total thyroidectomy Lifelong thyroxine replacement with tablets becomes necessary.