Surgical anatomy of the thyroid gland
- Melanie L Richards, MD, MHPE
Melanie L Richards, MD, MHPE
- Professor of Surgery
- Mayo Clinic College of Medicine
- Tracy S Wang, MD, MPH
Tracy S Wang, MD, MPH
- Associate Professor of Surgery
- Chief, Section of Endocrine Surgery
- Medical College of Wisconsin
- Julie Ann Sosa, MD, MA
Julie Ann Sosa, MD, MA
- Professor of Surgery and Medicine
- Chief, Section of Endocrine Surgery
- Leader, Endocrine Neoplasia Diseases Group
- Duke University Medical Center
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 .
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 thyroidectomy".)
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 . 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 . 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.
- Bliss RD, Gauger PG, Delbridge LW. Surgeon's approach to the thyroid gland: surgical anatomy and the importance of technique. World J Surg 2000; 24:891.
- Pankow BG, Michalak J, McGee MK. Adult human thyroid weight. Health Phys 1985; 49:1097.
- Hegedüs L. Thyroid size determined by ultrasound. Influence of physiological factors and non-thyroidal disease. Dan Med Bull 1990; 37:249.
- Braun EM, Windisch G, Wolf G, et al. The pyramidal lobe: clinical anatomy and its importance in thyroid surgery. Surg Radiol Anat 2007; 29:21.
- Pelizzo MR, Toniato A, Gemo G. Zuckerkandl's tuberculum: an arrow pointing to the recurrent laryngeal nerve (constant anatomical landmark). J Am Coll Surg 1998; 187:333.
- Reeve, TS, Delbridge, L. The tubercle of Zuckerkandl: a guide to thyroid and parathyroid surgery. Aust New Zealand Journal Surgery 1998; 68:59.
- Batsakis JG, El-Naggar AK, Luna MA. Thyroid gland ectopias. Ann Otol Rhinol Laryngol 1996; 105:996.
- Kousta E, Konstantinidis K, Michalakis C, et al. Ectopic thyroid tissue in the lower neck with a coexisting normally located multinodular goiter and brief literature review. Hormones (Athens) 2005; 4:231.
- Allard RH. The thyroglossal cyst. Head Neck Surg 1982; 5:134.
- Cernea CR, Ferraz AR, Nishio S, et al. Surgical anatomy of the external branch of the superior laryngeal nerve. Head Neck 1992; 14:380.
- Droulias C, Tzinas S, Harlaftis N, et al. The superior laryngeal nerve. Am Surg 1976; 42:635.
- Lifante JC, McGill J, Murry T, et al. A prospective, randomized trial of nerve monitoring of the external branch of the superior laryngeal nerve during thyroidectomy under local/regional anesthesia and IV sedation. Surgery 2009; 146:1167.
- Morton RP, Whitfield P, Al-Ali S. Anatomical and surgical considerations of the external branch of the superior laryngeal nerve: a systematic review. Clin Otolaryngol 2006; 31:368.
- Makay O, Icoz G, Yilmaz M, et al. The recurrent laryngeal nerve and the inferior thyroid artery--anatomical variations during surgery. Langenbecks Arch Surg 2008; 393:681.
- Serpell JW, Yeung MJ, Grodski S. The motor fibers of the recurrent laryngeal nerve are located in the anterior extralaryngeal branch. Ann Surg 2009; 249:648.
- Myssiorek D. Recurrent laryngeal nerve paralysis: anatomy and etiology. Otolaryngol Clin North Am 2004; 37:25.
- Henry JF, Audiffret J, Denizot A, Plan M. The nonrecurrent inferior laryngeal nerve: review of 33 cases, including two on the left side. Surgery 1988; 104:977.
- Pettiford J, Erasmus J, Grubbs EG, Perrier ND. Dysphagia lucoria: consideration for the endocrine surgeon. Surgery 2010; 147:890.
- Teitelbaum BJ, Wenig BL. Superior laryngeal nerve injury from thyroid surgery. Head Neck 1995; 17:36.
- American Thyroid Association Surgery Working Group, American Association of Endocrine Surgeons,, American Academy of Otolaryngology-Head and Neck Surgery, et al. Consensus statement on the terminology and classification of central neck dissection for thyroid cancer. Thyroid 2009; 19:1153.
- SIZE AND LOCATION
- Thyroid lobes
- Thyroid isthmus
- Pyramidal lobe
- Tubercle of Zuckerkandl
- Ectopic thyroid tissue
- BLOOD SUPPLY
- NERVE SUPPLY
- Superior laryngeal nerves
- - External branch
- - Internal branch
- Recurrent laryngeal nerve
- - Right recurrent laryngeal nerve
- - Left recurrent laryngeal nerve
- Non-recurrent laryngeal nerves
- Nerve injury
- LYMPHATIC DRAINAGE
- PARATHYROID GLANDS
- SUMMARY AND RECOMMENDATIONS