Thyroidectomy is the surgical removal of the thyroid gland, performed for colloid goiter, tumors, or hyperthyroidism that does not respond to iodine therapy and anti-thyroid drugs.
Surgical removal of the thyroid is necessary in some situations where a goiter becomes life-threatening or in the presence of some cancers.
Post-thyroidectomy treatment with thyroid hormone is routinely done to prevent a condition known as myxedema. The lack of circulating thyroid hormone in the body gives rise to a series of signs and symptoms which represent a severe form of hypothyroidism (underactivity of the thyroid gland). There is swelling of the face and limbs because of fluid deposited under the skin. This may particularly affect the area around the eyes, hands, and feet. The skin becomes dry and rough and there may be some hair loss. The person exhibits slowness of action and thought, and this mental dullness is accompanied by slow speech, with a voice that may become hoarse. Lethargy and weakness may be associated with slowed reflexes, a slow pulse, lowered metabolism and subnormal body temperature. Myxedema also may arise through primary disease of the thyroid.
Surgical removal is the treatment of choice for most thyroid carcinomas. The appropriate extent of removal is debatable; some surgeons favoring lobectomy and others near-total thyroidectomy.
The patient is rendered hypothyroid by withdrawing thyroid hormone for four to six weeks until the TSH (thyroid stimulating hormone) is significantly elevated to maximize the iodine uptake by thyroid tissue. At this time, a tracer dose of radioiodine is given, uptake determination and scan are done, and the ablative dose of 131I is calculated and given subsequently. This allows visualization and therapy of the thyroid tissue left in place after surgery and even of metastases that could not be visualized prior to thyroidectomy. Following this procedure, the patient is placed on suppressive doses of T4 (thyroxine, a thyroid hormone) indefinitely.