A subtotal thyroidectomy is a surgical operation that is performed to treat Graves’ disease. It involves the removal of most of the overactive tissue that produces and secretes excess amounts of thyroid hormone. Surgeons who perform subtotal thyroidectomies usually attempt to remove 90-95% of each lobe of the thyroid gland. This approach helps to limit the risk of causing damage to other structures in the neck. It also increases the chance of preserving normal thyroid function. Thyroid tissue that is left behind following a subtotal thyroidectomy may still function to produce and secrete adequate amounts of thyroid hormone.
Thyroid surgery was once the most common approach to the treatment of Graves’ disease. Its popularity has declined over the years in the United States as a result of the proven safety of treatment with antithyroid drugs and radioactive iodine. Thyroid surgery may still be considered as an option in circumstances where there may be a need for urgent treatment of severe or life-threatening hyperthyroidism. It may also be considered as an option when evaluation of an enlarged thyroid gland reveals the presence of a thyroid nodule that may represent a form of thyroid cancer. Thyroid surgery may represent the only viable option for treatment of hyperthyroidism associated with Graves’ disease when a patient who cannot tolerate antithyroid drugs does not want to pursue treatment with radioactive iodine.