Thyroid gland - Historical aspects, Embryology, Anatomy and Physiology

Thyroid gland is an important endocrine organ. Its hormone thyroxine is essential for life. The structure and function of thyroid gland were discovered during 17th to 20th centuries. Thyroid surgery is being done since early 19th century, perfected by Theodre Kocher in early 20th century. Thyroid is the first endocrine gland to develop in embryo and is endodermal origin. The surgically important anatomical relations of thyroid are recurrent laryngeal nerve, parathyroid glands and external laryngeal nerve with variations. Thyroid gland secretes thyroxine hormone which contains Iodine. Thyroxine has effects on all organs of body and its secretion is regulated by Pituitary. Present article throws light on some historical aspects, embryology, anatomy and physiology of thyroid gland based on relevant articles and textbooks.