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Surgical anatomy of the thyroid gland

Authors
Melanie L Richards, MD
Tracy S Wang, MD, MPH
Julie Ann Sosa, MD, MA
Section Editor
Sally E Carty, MD, FACS
Deputy Editor
Wenliang Chen, MD, PhD

INTRODUCTION

Emil Theodor Kocher and Theodor Billroth pioneered the surgical management of thyroid disease in the late 1800s. Their surgical techniques, knowledge of thyroid physiology, and antisepsis practices transitioned a life-threatening operation to one with acceptable morbidity. Meticulous technique, combined with an understanding of thyroid embryology and anatomy, is the foundation of the surgical management today. A thorough understanding of thyroid anatomy is central to the performance of safe thyroid surgery [1].

Thyroid anatomy is discussed here. The indications for thyroidectomy and surgical techniques are discussed elsewhere. (See "Surgical management of hyperthyroidism" and "Differentiated thyroid cancer: Surgical treatment" and "Initial and reoperative thyroidectomy".)

FUNCTION

Thyroid hormones, thyroxine (T4), and 3,5,3'-triiodothyronine (T3), are critical determinants of brain and somatic development in infants and of metabolic activity in adults; they also affect the function of virtually every organ system. Thyroid hormone biosynthesis and secretion are maintained within narrow limits by a regulatory mechanism that is sensitive to small changes in circulating hormone concentrations.

The processes of thyroid hormone synthesis, transport, and metabolism, and the regulation of thyroid secretion and actions of thyroid hormone are discussed elsewhere. (See "Thyroid hormone synthesis and physiology" and "Thyroid hormone action".)

SIZE AND LOCATION

The thyroid gland weighs 10 to 20 grams in normal adults [2]. Thyroid volume measured by ultrasonography (US) is slightly greater in men than women, increases with age and body weight, and decreases with increasing iodine intake [3]. The thyroid is one of the most vascular organs in the body. Thus, US measurements of thyroid volume and even nodule size can differ markedly from the size after devascularization and resection.

                   

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Literature review current through: Nov 2016. | This topic last updated: Wed Sep 02 00:00:00 GMT+00:00 2015.
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