Thyroidectomy is a surgical procedure commonly used to treat hyperthyroidism. Along with radioiodine ablation and antithyroid drug therapy, thyroidectomy is one of the major conventional treatment options used for the treatment of Graves’ disease. By limiting the amount of thyroid tissue capable of producing thyroid hormone, blood levels of thyroid hormone are effectively reduced. Because thyroid antibodies are produced by thyroid tissue, thyroidectomy also diminishes the number of thyroid antibodies, which are the cause of hyperthyroidism in Graves’ disease. Like radioiodine ablation, surgery is an invasive procedure, although surgery poses less of a risk for thyroid storm, a frequent complication of radioiodine ablation.
The normal thyroid gland weighs about 20 grams, although the thyroid gland in Graves’ disease is often much larger. There are two types of thyroidectomy surgery: total thyroidectomy in which the entire thyroid gland is removed and subtotal thyroidectomy in which most of the thyroid gland is removed although a small amount of thyroid tissue, usually less than 5-10 grams, is left. The advantage of subtotal thyroidectomy is that the risk for permanent hypothyroidism is reduced. Even when patients become hypothyroid after surgery, it is to a lesser degree than for patients who have total thyroidectomies. Because synthetic thyroid replacement hormone used to treat hypothyroidism does not contain the entire spectrum of thyroid precursor hormones found in the thyroid gland, it’s desirable to leave a small amount of viable tissue.
In one recent study conducted in India, 72 patients, 50 women and 22 men, were operated on to reduce their symptoms of Graves disease. Their median age was 35 years. The indications that surgery would be the best option for these patients included: large goiter size, prior relapse after antithyroid drug therapy, allergic reactions to antithyroid drugs, non-compliance and associated nodule with suspicion of carcinoma.
Before surgery, patients were rendered euthyroid with antithyroid drugs, and they were pretreated with Lugol’s solution of saturated potassium iodide. Lugol’s solution changes the consistency of the thyroid tissue, reducing its vascularity to facilitate surgery.
Standard subtotal thyroidectomy was performed in 64 of the patients in the study while 7 had total thyroidectomy, and one patient had a total thyroidectomy after first having a subtotal thyroidectomy. For patients having subtotal thyroidectomy, approximately 3-5 grams was left of each lobe.
Follow-up: none of the patients had complications of postoperative death or thyroid storm. Eight patients (11.1%) had temporary unilateral vocal cord palsy and 4 patients (5.5%) had temporary hypocalcemia (low blood calcium level). These symptoms were temporary and resolved. One patient (1.4%) developed recurrent hyperthyroidism that resolved.
