Thyroid Surgery Options

Fig.1: Intraoperative nerve monitorThyroid surgery is the most common operation performed in endocrine surgery. The term thyroidectomy covers a variety of surgical procedures that can be performed on the thyroid gland, depending on the amount of thyroid tissue removed. Details of thyroid anatomy can be found on the webpage Anatomy.

All of my patients at the Freemasons Hospital will have their surgery performed with an intraoperative nerve monitor (Fig. 1), which is used to test and safeguard the recurrent laryngeal nerves (nerves to the voicebox) during your surgery. This nerve monitor minimises the potential risk to the voice to a very low level.

Day Case Thyroid Surgery

Generally speaking, all forms of thyroid surgery require at least an overnight stay in hospital to monitor and treat any possible complications (particularly bleeding into the neck). Whilst postoperative bleeding into the neck is rare in my hands, if it occurs it can be life-threatening because of acute obstruction of the airway. Immediate removal of the skin sutures may be needed, followed by a rapid return to theatre.

Many studies have shown that if bleeding is going to happen it will almost always occur in the first 24 hours after surgery, and mostly within the first 6 hours. A recent study by the British Association of Endocrine and Thyroid Surgeons (BAETS) showed that although day case thyroidectomy was certainly possible, the risk of catastrophic bleeding taking place at home made it inadvisable. For these reasons I always keep patients in hospital at least overnight after thyroid surgery. 

Detailed information about your surgery can be found on the webpage Guide to Surgery.

If you would like more detail about the surgical technique, this information can be found on webpage Details of surgery although it may contain pictures that some patients may not wish to see. Information about potential complications can be found on webpage Potential Complications.

When operating on the thyroid, a surgeon can perform any one of the following:

Thyroid Lobectomy or Hemithyroidectomy

Fig.2: Right lobectomy of the thyroid (purple area is removed)In this procedure, the surgeon will remove one lobe of the thyroid, usually with the isthmus, which is the part of the thyroid that joins the two lobes together, plus the pyramidal lobe, if present - see Anatomy (Fig. 2). The operation generally takes about an hour to complete and is performed under a general anaesthetic.

This operation is performed to remove a nodule (solitary hot or cold nodules) and goitres that can occur in just one lobe. It is also used for benign Hurthle cell tumours and for non-aggressive thyroid cancers.

It is not uncommon for the nodular process to only affect one side, rather than the whole gland, as might be expected. Even when there are nodules on the opposite side to the worst affected lobe, provided they are small and few in number, it may be possible to preserve one side, instead of having a total thyroidectomy.

By having only a lobectomy the patient has a very strong chance of avoiding the need for thyroxine replacement tablets for life. In older patients the risk of needing thyroxine replacement after a lobectomy is about 25-30%, but in younger patients this risk is only 5-10%.

It is important to remember that having only a hemithyroidectomy when there is nodular disease on both sides (even if only minor disease on one side, as mentioned above) may only put off the inevitable need for the rest of the thyroid to be removed in later life. But of course the advantage of a lesser operation is that in most cases it means putting off the day when you have to start taking thyroxine tablets for some years!

Subtotal lobectomy or nodulectomy is where the surgeon removes only part of one lobe of the thyroid or just the nodule. This operation is inadequate and not recommended. Removal of just the nodule carries a much higher risk of bleeding postoperatively, and the potential to spill tumour cells in the neck if the nodule turns out to be a cancer on pathology.

The risks to the voice and the parathyroids are much higher if a second operation is needed to complete a lobectomy, which is not uncommon due to inadequate clearance around a nodule or tumour.

Subtotal Thyroidectomy

Fig.3: Thyroid tissue remnants in subtotal thyroidectomyThis procedure is used to remove almost all the thyroid, but still leaving enough of the gland to produce some hormones (Fig. 3). The problem with the operation is to decide how much thyroid to leave behind to minimise the risk of recurrence, while leaving enough thyroid capacity to maintain normal thyroid hormone levels.

Because of this subtotal thyroidectomy has fallen out of favour and has been replaced by either total thyroidectomy or thyroid lobectomy alone.

There is no evidence that this is a safer operation for the voice or for the parathyroids, and it can in fact be the reverse. Recurrence of the goitre after subtotal thyroidectomy can lead to very difficult redo surgery down the track, with a much higher risk of complications.

The risk of hypothyroidism with subtotal thyroidectomy is quite high, with more than 70 percent of patients becoming hypothyroid after a subtotal thyroidectomy.

Since one of the main reasons for subtotal thyroidectomy is to prevent hypothyroidism, and that goal is achieved in only a minority of cases, there is no added benefit to the operation and total thyroidectomy has become the routine recommendation.

Total Thyroidectomy

Fig.4: Total thyroidectomy (whole thyroid removed)This procedure removes all the thyroid gland (Fig. 4). It is used in cases of thyroid cancers, Hurthle cell tumours and is the usual operation for multinodular goitres and in patients who need surgery for treatment of Graves' disease.

It may also be the best operation in some cases where there is a very strong suspicion of thyroid cancer, but the fine needle biopsy has not been able to definitively prove it before surgery. If the size of the thyroid nodule or other associated clinical features strongly suggest a likelihood of thyroid cancer, then total thyroidectomy may also be recommended.

This will avoid the potential need for a second operation, although in some cases it means that normal thyroid may have been removed unnecessarily if the nodule proves to be benign after all.

The operation generally takes from 90 minutes to two hours to complete, and is performed under a general anaesthetic. The general principles of the operation involve dividing the blood supply to the thyroid next to the gland, identifying the recurrent laryngeal nerve and carefully tracing its path up to the voice box, and preserving the parathyroid glands if possible. More detailed information about the actual surgical technique can be found on the webpage Details of Surgery.

This operation leaves no thyroid tissue behind, so all patients will need thyroxine replacement tablets for life. In specialist hands it carries no greater risk of complications, and has a whole lot more advantages than a subtotal thyroidectomy.