The extirpation of the thyroid gland . . . typifies, perhaps better than any operation, the supreme triumph of the surgeon's art.... A feat which today can be accomplished by any competent operator without danger of mishap and which was conceived more than one thousand years ago.... There are operations today more delicate and perhaps more difficult.... But is there any operative problem propounded so long ago and attacked by so many . . . which has yielded results as bountiful and so adequate?
Dr. William S. Halsted, 1920
Modern thyroid surgery, as we know it today, began in the 1860s in Vienna with the school of Billroth (1). The mortality associated with thyroidectomy was high, recurrent laryngeal nerve injuries were common, and tetany was thought to be caused by “hysteria.” The parathyroid glands in humans were not discovered until 1880 by Sandstrom (2), and the fact that hypocalcemia was the definitive cause of tetany was not wholly accepted until several decades into the twentieth century. Kocher, a master thyroid surgeon who operated in the late nineteenth and early twentieth centuries in Bern, practiced meticulous surgical technique and greatly reduced the mortality and operative morbidity of thyroidectomy for goiter. He described “cachexia strumipriva “ in patients years after thyroidectomy (3) (Fig 1). Kocher recognized that this dreaded syndrome developed only in patients who had total thyroidectomy. As a result, he stopped performing total resection of the thyroid. We now know, of course, that cachexia strumipriva was surgical hypothyroidism. Kocher received the Nobel Prize for this very important contribution, which proved beyond a doubt the physiologic importance of the thyroid gland.
Figure 1. The dramatic case of Maria Richsel, the first patient with postoperative myxedema to have come to Kocher’s attention. A. The child and her younger sister before the operation. B. Changes 9 years after the operation. The younger sister, now fully grown, contrasts vividly with the dwarfed and stunted patient. Also note Maria’s thickened face and fingers, which are typical of myxedema. (From Kocher T: Uber Kropfextirpation und ihre Folgen. Arch Klin Chir 29:254, 1883.)
By 1920, advances in thyroid surgery had reached the point that Halsted referred to this operation as a “feat which today can be accomplished by any competent operator without danger of mishap” (1). Unfortunately, decades later, complications still occur. In the best of hands, however, thyroid surgery can be performed today with a mortality that varies little from the risk of general anesthesia alone, as well as with low morbidity. To obtain such enviable results, however, surgeons must have a thorough understanding of the pathophysiology of thyroid disorders; be versed in the preoperative and postoperative care of patients; have a clear knowledge of the anatomy of the neck region; and use an unhurried, careful, and meticulous operative technique.
The thyroid (which means “shield”) gland is composed of two lobes connected by an isthmus that lies on the trachea approximately at the level of the second tracheal ring (Fig. 2). The gland is enveloped by the deep cervical fascia and is attached firmly to the trachea by the ligament of Berry. Each lobe resides in a bed between the trachea and larynx medially and the carotid sheath and sternocleidomastoid muscles laterally. The strap muscles are anterior to the thyroid lobes, and the parathyroid glands and recurrent laryngeal nerves are associated within the posterior surface of each lobe. A pyramidal lobe is often present. This structure is a long, narrow projection of thyroid tissue extending upward from the isthmus and lying on the surface of the thyroid cartilage. It represents a vestige of the embryonic thyroglossal duct, and it often becomes palpable in cases of thyroiditis or Graves’ disease. The normal thyroid varies in size in different parts of the world, depending on the iodine content in the diet. In the United States it weighs approximately 15 grams.
